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Quantitative characterization of important metabolites of avocado fruit by gas chromatography coupled to different detectors (APCI-TOF MS and FID)
... The most common derivatization reaction is through the substitution of the active hydrogen of polyphenols and phenolic acids by the trimethylsilyl (TMS) group (-Si(CH3)3), because of the simplicity of this derivatization reaction, the fact that this process is almost instantaneous (allowing the derivatization of both acids and phenols simultaneously), and the side products generated are extremely volatile without interfering in the analysis [50]. Several derivatization reagents are employed: N,O-bis-(trimethylsilyl) trifluoroacetamide (BSTFA) [51][52][53], N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA) [54], or trimethylsilyl cyanide (TMSCN) [55], among others. For example, Khakimov et al. [55] carried out a comprehensive and comparative metabolomic profiling of wheat, barley, oat and rye using GC-MS. ...
... As previously commented, GC hyphenated with TOF MS instruments have also been employed to authenticate food products, mainly under a metabolomic approach for which HRMS is normally the best option due to their higher resolution and accurate mass measurements [51,53,54]. As an example, Kim et al. described the metabollomic profiling of millet (Panicum miliaceum) cereal plant by GC-TOFMS for quality assesment. ...
... Another trend that can be highlighted with GC-MS techniques in the determination of polyphenols to characterize and authenticate food products is the use of atmospheric pressure chemical ionization (APCI) as the ionization source [51,53], mainly in the positive ionization mode, as an alternative to the most frequently employed electronic ionization (EI). For example, Hurtado-Fernández et al. [51] carried out the quantitative characterization of the most important metabolites found in avocado fruit by GC-APCI-TOF MS and GC-FID. ...
The quality of food products is an issue of worldwide interest in our society. Moreover, although consumer preferences regarding food products are often influenced by organoleptic (e.g., color, taste, aroma, etc.) and socioeconomic (e.g., ecological production, guaranteed origin and quality, etc.) factors, people are increasingly more interested in the presence of some specific compounds with health beneficial properties, the so-called bioactive substances.
Polyphenols consist of one of the most abundant family of bioactive compounds in foods that caught the attention of consumers over the last few years. They are aromatic secondary metabolites ubiquitously spread through the plant kingdom comprising more than 8,000 substances with highly diverse structures, and with molecular masses ranging from small molecules (<100 Da) such as phenolic acids to big molecules (>30,000 Da) of highly polymerized compounds. The main reasons for the interest in polyphenols deal with the recognition of their antioxidant properties, the great abundance in our diet, their contribution on food products’ sensorial properties, and their probable role in the prevention of several diseases such as diabetes or even cancer. However, the importance of polyphenols in foodstuffs comes also to the fact that the type of polyphenols as well as their distribution and concentration levels in fruit- and vegetable-based products depends not only on the fruit or vegetable employed but on many other parameters such as the climate conditions, water resources, growing area, cultivation techniques, soil management, and degree of maturation of fruits and vegetables, among others. As a result, polyphenolics, i.e., the distribution and content of polyphenols, in plant-based food products can be exploited as a source of analytical data to assess food authentication.
This chapter aims to address the role that polyphenolics is playing in the assessment of food integrity and authenticity. Analytical methodologies typically employed for the determination of polyphenols such as capillary electrophoresis, gas chromatography, liquid chromatography, and mass spectrometry, and the strategies used to correlate polyphenol concentration or polyphenolic profiles with food authentication based on chemometric techniques will be discussed by means of relevant examples. Coverage of all kind of applications is beyond the scope of the present contribution that will focus on the most relevant ones published in the last years.
... However, there are important knowledge gaps regarding the contents of certain nutrients and bioactive compounds in 'Hass' avocados. The contents of oils, fatty acids, sugars and phenolic compounds have been determined extensively in the pulp of 'Hass' but little is known about the contents of either nutrients or bioactive compounds in avocado peels, which are a significant agroindustry by-product generated at high volumes with many potential uses (Hurtado-Fernández, Pacchiarotta, Mayboroda, Fernández-Gutiérrez, & Carrasco-Pancorbo, 2014;López-Cobo et al., 2016;Morais et al., 2017). 'Hass' peel anthocyanin content has been determined only in a few studies (Ashton et al., 2006;Cox, McGhie, White, & Woolf, 2004). ...
... The organic acid composition has been scarcely investigated in avocado fruit and few recent studies are available in this regard . Unfortunately, some acids previously reported in avocado fruit, especially some phenolic acids, were not identified in the tested tissues (Hurtado-Fernández et al., 2014). The contents of organic acids in the pulp of CA and 'Hass' fruits totaled 17.13-255.70 ...
... Other phenolic compounds have been identified in the pulp of ripe avocados, which were not identified in our study. Hurtado-Fernández et al. (2014) reported the acids 4-hydroxybenzoic, syringic and ferulic, while López-Cobo et al. (2016) reported some glycosylated phenols in avocados, including pcoumaric acid glucoside, p-coumaric acid rutinoside, ferulic acid glucoside, and sinapic acid-C-hexoside, among others. The differences in the profile of these compounds in avocados may be due to differences in the activity of phenylalanine ammonia lyase (PAL). ...
The physicochemical properties, including nutrient and bioactive compound compositions, in fruit of four creole avocados (CA) from Mexico were determined and compared with those of 'Hass' fruit. 'Hass' pulp and some CA pulps contained similar concentrations of lutein, chlorophyll a, β-sitosterol and α-tocopherol. CA pulp contained 3.91-9.55% more oil than 'Hass'. Oil from CA pulp contained 10.10-26.79% more oleic acid than 'Hass' pulp. However, CA were small (CA= 81.40-137.15 g, ‘Hass’= 188.59 g) and their pulp contents were low (CA= 39.83-84.82 g, ‘Hass’= 144.14 g). CA peels were very thin, making these avocado peels edible but prone to mechanical damage. CA peels also contained higher concentrations and greater diversity of anthocyanins and glycosylated quercetin compounds than 'Hass' peels. Some CA were particularly rich in mannoheptulose and perseitol. Consumption of CA, including their peel, might result in higher intakes of some nutrients and bioactive compounds compared with 'Hass' avocados.
... The fruit of some HT cultivars (e.g. Lamb Hass, Gem, Harvest, Jimenez 1, Jimenez 2, and Tacambaro) have an exceptionally higher content of oleic acid and some phenolic compounds (epicatechin and the acids chlorogenic, p-coumaric, and quinic) than Hass fruit (Mpai and Sivakumar, 2020;Hurtado-Fernández et al., 2014). HT fruit are also characterized by a longer postharvest life and higher pulp content compared to Hass fruit (Tapia-Vargas, et al., 2017). ...
... Unfortunately, very limited information is available on other important characteristics of HT fruit, including their content of phytochemicals and nutrients. The current knowledge on phytochemical and nutrient composition of avocado fruit is based almost exclusively on Hass avocados (Amado et al., 2019;Ashton et al., 2006;Blakey et al., 2012;Campos et al., 2020;Hurtado-Fernández et al., 2014;Villa-Rodríguez et al., 2020). Thus, the objective of this work was to compare the chemical composition and other characteristics of fruit of HT cultivars, developed in or introduced to Mexico, with those of Hass fruit. ...
... The extraction of phenolic compounds was carried out according to Mertz et al. (2007), replacing acetone with methanol as the extraction solvent. Hurtado-Fernández et al. (2014) demonstrated that the extraction of phenolic compounds from avocado pulp was more efficient with methanol that with acetone, ethanol, or ethyl acetate, which are also commonly used for extraction of these compounds. Briefly, pulp samples (4 g) were homogenized with methanol (40 mL) containing 0.1 % of trifluoroacetic acid (TFA). ...
The pulp of ripe fruit of Hass and fourteen Hass type (HT) avocado cultivars was evaluated for phytochemicaland nutrient composition. All HT fruit had similar appearance to that of Hass, however, the ripening rate of most HT fruit was generally faster than that of Hass, with this being an important disadvantage for HT fruit. Six sugars, seven organic acids, nine fatty acids, eleven carotenoids, five chlorophylls and related compounds, three phytosterols, one phytostanol, two tocopherols and several phenolic compounds were identified and quantified in the tested pulps. The content of these compounds varied significantly between cultivars. Some HT pulps had up to 7.00%, 53.2%, 93.2%, 85.7%, 71.3%, and 96.1% more oil, oleic acid, β-sitosterol, lutein, chlorophyll b, and cycloartenol than Hass pulp. All fruit showed ratios of n-6 to n-3 and polyunsaturated to saturated fatty acids commonly associated with the prevention of cardiovascular diseases. Other HT pulps had higher content of phenolic compounds and 7-C sugars, especially mannoheptulose, than Hass pulp. Ascorbic acid content in the tested fruit was very low. Some HT fruit showed a good balance between polar and non-polar bioactive compounds. Overall, some HT fruit had better phytochemical and nutrient composition than Hass fruit.
... [3] The current commercial varieties are hybrids of the races. For example, the Hass variety belongs to the Guatemalan-Mexican hybrid group, Pulp, seed, peel 0.082-1,920 (peel) 24.3-2,000 (seed) [12,16,[23][24][25][26][27][28][29][30] Caffeic acid Leaf, peel, seed 13.7-22.5 (seed) 8,010 (peel) [10,12,22,25,26,28,[31][32][33] Cinnamic acid Pulp, seed, peel [16,26] Chlorogenic acid Leaf, pulp, peel, seed 0.0516-1,953 (seed) 137.6-4,290 (peel) [10,12,13,22,24,25,30,31,[34][35][36][37][38] Coumaric acid Leaf, pulp, peel, seed 1.74-2.2 ...
... For example, the Hass variety belongs to the Guatemalan-Mexican hybrid group, Pulp, seed, peel 0.082-1,920 (peel) 24.3-2,000 (seed) [12,16,[23][24][25][26][27][28][29][30] Caffeic acid Leaf, peel, seed 13.7-22.5 (seed) 8,010 (peel) [10,12,22,25,26,28,[31][32][33] Cinnamic acid Pulp, seed, peel [16,26] Chlorogenic acid Leaf, pulp, peel, seed 0.0516-1,953 (seed) 137.6-4,290 (peel) [10,12,13,22,24,25,30,31,[34][35][36][37][38] Coumaric acid Leaf, pulp, peel, seed 1.74-2.2 (peel) [12,25,26,28,31,32] Cyanidin 3-O-glucoside Peel 3,000 (peel) [ Leaf, seed [13,26,32] (Continued ) ...
... For example, the Hass variety belongs to the Guatemalan-Mexican hybrid group, Pulp, seed, peel 0.082-1,920 (peel) 24.3-2,000 (seed) [12,16,[23][24][25][26][27][28][29][30] Caffeic acid Leaf, peel, seed 13.7-22.5 (seed) 8,010 (peel) [10,12,22,25,26,28,[31][32][33] Cinnamic acid Pulp, seed, peel [16,26] Chlorogenic acid Leaf, pulp, peel, seed 0.0516-1,953 (seed) 137.6-4,290 (peel) [10,12,13,22,24,25,30,31,[34][35][36][37][38] Coumaric acid Leaf, pulp, peel, seed 1.74-2.2 (peel) [12,25,26,28,31,32] Cyanidin 3-O-glucoside Peel 3,000 (peel) [ Leaf, seed [13,26,32] (Continued ) ...
Avocado (Persea americana Mill) is a native American fruit. Its industrial processing generates a large number of wastes (leaves, peels, and seeds). These wastes are a source of bioactive compounds which have been attributed biological activities. We aim to compile scientific research on bioactive compounds of avocado pulp and wastes and their potential biological properties. Main bioactive compounds identified in pulp and wastes are polyphenols, carotenoids, tocopher-ols, and phytosterols. Thus, wastes extracts have reported numerous biological activities, e.g., antimicrobial, anti-inflammatory, anticancer, antidiabetic, antihypertensive. Therefore, potential applications in food and pharmaceutical industries can be issued.
... Regarding a detector for GC, flame ionization detector (FID) is considered as one of the most universal and popular detectors for GC, as a consequence of its simplicity, its resistance to small fluctuations of the gas flow, reasonable sensitivity, insensitive to gas impurities, and excellent linear range [88,89]. On the other hand, GC in combination with MS has been broadly exploited, since this coupling puts together the separation power of GC with the capabilities of the modern MS instruments. ...
... However, the combination of GC-MS and GC-FID has never developed into a routine analytical method, due to considerable technical problems with the synchronization of FID and vacuum-stage MS [89]. They are running mostly separately [88,95,96] or in heart cut mode [97]. But in some cases, the use of parallel detectors was also reported [98,99]. ...
... The co-elution and overlapping in complex samples analysis, which cannot be solved by FID, complicate the determination of compounds present at low concentration levels very much. Hurtado-Fern andez et al. [88] reported for the analysis of avocado fruit that GC-APCI-MS allowed the quantification of 27 metabolites, whereas by using GC-FID only 7 analytes could be quantified, because API-MS provides highquality structural information, which is essential for the data interpretation. With an API source, the protonated molecule [MþH] þ is largely preserved. ...
Although the coupling of GC/MS with atmospheric pressure ionization (API) has been reported in 1970s, the interest in coupling GC with atmospheric pressure ion source was expanded in the last decade. The demand of a "soft" ion source for preserving highly diagnostic molecular ion is desirable, as compared to the "hard" ionization technique such as electron ionization (EI) in traditional GC/MS, which fragments the molecule in an extensive way. These API sources include atmospheric pressure chemical ionization (APCI), atmospheric pressure photoionization (APPI), atmospheric pressure laser ionization (APLI), electrospray ionization (ESI) and low temperature plasma (LTP). This review discusses the advantages and drawbacks of this analytical platform. After an introduction in atmospheric pressure ionization the review gives an overview about the history and explains the mechanisms of various atmospheric pressure ionization techniques used in combination with GC such as APCI, APPI, APLI, ESI and LTP. Also new developments made in ion source geometry, ion source miniaturization and multipurpose ion source constructions are discussed and a comparison between GC-FID, GC-EI-MS and GC-API-MS shows the advantages and drawbacks of these techniques. The review ends with an overview of applications realized with GC-API-MS.
... On the other hand, a large number of halophyte plants have been traditionally used to reduce blood pressure (Salsola kali L., Chenopodiaceae), for the treatment of cancer (Artemisia scopariae Waldst. and Kit., Asteraceae), and microbial infections (e.g., M. edule, Aizoaceae) [16] as well as antioxidant, anti-inflammatory, and antitumoral activities [17]. ...
... This plant is abundant in saltmarshes along the coastlines of Europe, South-West Asia, and North Africa [18]. In folkloric medicine, A. indicum has been commonly used to treat poisonous bites and stings and possesses beneficial effects against numerous other diseases [16]. The antiproliferative effect of A. indicum shoot (leaves and stems) extracts was compared to the control, and the results are very encouraging [8]. ...
The purpose of this study was to evaluate for the first time the phytochemical constituents and biological properties of three (ethanol, acetone, and hexane) Arthrocnemum indicum (Willd.) Moq. (A. indicum) extracts. Quantitative analysis revealed the significantly (p < 0.05) dominance of ethanolic extract on total polyphenol (TPC; 303.67 ± 4.16 mg GAE/g DR) and flavonoid (TFC; 55.33 ± 2.52 mg CE/g DR) contents than the other extracts, also displaying high and equipotent condensed tannin (TCTC) contents as the acetone extract. The qualitative HPLC-MS analysis elucidates 19 and 18 compounds in ethanolic and acetonic extracts, respectively, belonging to the phenolics and flavonoids chemical classes. The extracts were also screened for their in vitro antioxidant activities using 1,1-diphenyl-2-picrylhydrazyl, superoxide anion, and ferric ion (Fe3+) reducing antioxidant power (FRAP), demonstrating the potent antioxidant activity of ethanolic extract, due to its stronger scavenging DPPH• (IC50 = 7.17 ± 1.26 μg/mL) which is not significantly (p > 0.05) different from the positive control, BHT (IC50 = 10.70 ± 0.61 μg/mL), however moderate activity through FRAP and superoxide anion radicals have been observed. Four Gram-positive, four Gram-negative bacteria, and four pathogenic fungi were used for the antimicrobial activity. In addition, S. epidermidis, M. luteus, E. faecalis, C. glabrata, C. parapsilosis, C. krusei were found to be the most susceptible strains towards ethanolic extract. Cytotoxicity values against human colon adenocarcinoma cells (HT29) and human epidermoid cancer cells (Hep2), and one continuous cell lineage control (Vero) revealed that the HT29 cancer cell line was the most responsive to A. indicum shoot extract treatment and significantly (p < 0.05) different from the other cancer cells. Moreover, when tested for their antidiabetic inhibitory effect, ethanol extract recorded the highest antidiabetic effect with IC50 = 13.17 ± 1.04 mg/mL, which is 8.4-fold higher than acetone extract. Therefore, the present study provides new findings on the use of A. indicum shoot ethanolic extract to cure many incurable diseases.
... Thus, a very brief introduction to studies on the topic is incorporated in this review. Hurtado-Fernández et al. (2014, 2015a) evaluated 13 different avocado cultivars including Hass at two different ripeness stages (at physiological maturity and ready to eat ripeness stages) and reported that the concentration of organic acids and phenolic acids generally decreased as the fruit ripened, except for phenolic acids such as ferulic and p-coumaric which increased in concentration as the fruit ripened. Hass avocado at harvest presented a lower amount of benzoic acid compared to the ready to eat stage. ...
... Hass avocado at harvest presented a lower amount of benzoic acid compared to the ready to eat stage. But, the quinic acid concentration in Hass was higher at harvest and decreased at the ready to eat stage (Hurtado-Fernández et al., 2014). Lately, Hurtado-Fernández et al. (2016) reported the evolution of six important metabolites from the phenylpropanoid pathway including phenolic acids (pantothenic, p-coumaric, and ferulic acid) and epicatechin, chlorogenic acid, and abscisic in different avocado cultivars over different harvest seasons depending on the variety. ...
Avocado (Persea americana Mill) is rich in a variety of essential nutrients and phytochemicals; thus, consumption has drastically increased in the last 10 years. Avocado unlike other fruit is characterized by oil accumulation during growth and development and presents a unique carbohydrate pattern. There are few previous and current studies related to primary metabolism. The fruit is also quite unique since it contains large amounts of C7 sugars (mannoheptulose and perseitol) acting as transportable and storage sugars and as potential regulators of fruit ripening. These C7 sugars play a central role during fruit growth and development, but still confirmation is needed regarding the biosynthetic routes and the physiological function during growth and development of avocado fruit. Relatively recent transcriptome studies on avocado mesocarp during development and ripening have revealed that most of the oil is synthesized during early stages of development and that oil synthesis is halted when the fruit is harvested (pre-climacteric stage). Most of the oil is accumulated in the form of triacylglycerol (TAG) representing 60–70% in dry basis of the mesocarp tissue. During early stages of fruit development, high expression of transcripts related to fatty acid and TAG biosynthesis has been reported and downregulation of same genes in more advanced stages but without cessation of the process until harvest. The increased expression of fatty acid key genes and regulators such as PaWRI1, PaACP4-2, and PapPK-β-1 has also been reported to be consistent with the total fatty acid increase and fatty acid composition during avocado fruit development. During postharvest, there is minimal change in the fatty acid composition of the fruit. Almost inexistent information regarding the role of organic acid and amino acid metabolism during growth, development, and ripening of avocado is available. Cell wall metabolism understanding in avocado, even though crucial in terms of fruit quality, still presents severe gaps regarding the interactions between cell wall remodeling, fruit development, and postharvest modifications.
... Thus, a very brief introduction to studies on the topic is incorporated in this review. Hurtado-Fernández et al. (2014, 2015a) evaluated 13 different avocado cultivars including Hass at two different ripeness stages (at physiological maturity and ready to eat ripeness stages) and reported that the concentration of organic acids and phenolic acids generally decreased as the fruit ripened, except for phenolic acids such as ferulic and p-coumaric which increased in concentration as the fruit ripened. Hass avocado at harvest presented a lower amount of benzoic acid compared to the ready to eat stage. ...
... Hass avocado at harvest presented a lower amount of benzoic acid compared to the ready to eat stage. But, the quinic acid concentration in Hass was higher at harvest and decreased at the ready to eat stage (Hurtado-Fernández et al., 2014). Lately, Hurtado-Fernández et al. (2016) reported the evolution of six important metabolites from the phenylpropanoid pathway including phenolic acids (pantothenic, p-coumaric, and ferulic acid) and epicatechin, chlorogenic acid, and abscisic in different avocado cultivars over different harvest seasons depending on the variety. ...
Avocado (Persea americana Mill) is rich in a variety of essential nutrients and phytochemicals; thus, consumption has drastically increased in the last 10 years. Avocado unlike other fruit is characterized by oil accumulation during growth and development and presents a unique carbohydrate pattern. There are few previous and current studies related to primary metabolism. The fruit is also quite unique since it contains large amounts of C7 sugars (mannoheptulose and perseitol) acting as transportable and storage sugars and as potential regulators of fruit ripening. These C7 sugars play a central role during fruit growth and development, but still confirmation is needed regarding the biosynthetic routes and the physiological function during growth and development of avocado fruit. Relatively recent transcriptome studies on avocado mesocarp during development and ripening have revealed that most of the oil is synthesized during early stages of development and that oil synthesis is halted when the fruit is harvested (pre-climacteric stage). Most of the oil is accumulated in the form of triacylglycerol (TAG) representing 60–70% in dry basis of the mesocarp tissue. During early stages of fruit development, high expression of transcripts related to fatty acid and TAG biosynthesis has been reported and downregulation of same genes in more advanced stages but without cessation of the process until harvest. The increased expression of fatty acid key genes and regulators such as PaWRI1, PaACP4-2, and PapPK-β-1 has also been reported to be consistent with the total fatty acid increase and fatty acid composition during avocado fruit development. During postharvest, there is minimal change in the fatty acid composition of the fruit. Almost inexistent information regarding the role of organic acid and amino acid metabolism during growth, development, and ripening of avocado is available. Cell wall metabolism understanding in avocado, even though crucial in terms of fruit quality, still presents severe gaps regarding the interactions between cell wall remodeling, fruit development, and postharvest modifications.
... As stated before, the same sample set has been previously analyzed by using different analytical platforms, such as UHPLC-ESI-TOF MS, 6 GC-APCI-TOF MS, 28 and GC-FID/MS, 45 looking for possible varietal and/or ripening markers of avocado fruits. Comparing the results achieved in this study with those obtained in the other three manuscripts, it is very interesting to emphasize that three of the identiers (mannoheptulose, linoleic and aspartic acids) pointed out herein were highlighted as identiers aer the statistical analysis of the GC-APCI-TOF MS data. ...
... Comparing the results achieved in this study with those obtained in the other three manuscripts, it is very interesting to emphasize that three of the identiers (mannoheptulose, linoleic and aspartic acids) pointed out herein were highlighted as identiers aer the statistical analysis of the GC-APCI-TOF MS data. 28 In the study carried out by using GC-FID and GC-APCI-MS, 45 abscisic acid was obtained as the relevant metabolite in sample classication, although it was not the most outstanding classier. However, the most inuential metabolites for the classication achieved by UHPLC-MS were not the same compounds as those underlined by GC-EI-Q MS, a fact which could be expected considering the different selectivity of both platforms. ...
Herewith the usefulness of a gas chromatography-electron ionization-quadrupole mass spectrometry (GC-EI-Q MS) methodology has been evaluated for the identification of potential ripening or variety markers of the avocado fruit. A selection of 13 avocado varieties at two diverse ripening degrees was made and their derivatized extracts were analyzed by GC-MS. Even though the method was able to identify about 60 metabolites within a single run, the approach used was more exploratory, and data processing and analysis steps were carried out, implying filtering, normalization, principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). 17 compounds were selected as the most influential to be considered in PCA and clustering analysis by the k-means method. To corroborate further on the metabolic changes associated with ripening, a two class PLS-DA model was built, identifying abscisic acid, linoleic acid, aspartic acid and mannoheptulose as the compounds with the highest influence in the model.
... The extracts of 13 avocado varieties at two ripening degrees have been analyzed within this study and very complex profiles were obtained by using the described GC-APCI-MS platform. Although the main goal of the study was carrying out an exploratory analysis of the profiles, the identification of an important number of metabolites could be achieved bearing in mind previously published results [21,25,26] and the valuable information obtained by the analytical platform used. Figure 1 shows, as example, the chromatograms achieved by GC-APCI-TOF MS for an avocado cultivar at first and second ripening degrees, where it is possible to perceive the complexity of the profiles. ...
... Table 1 the discriminative features. A tentative identity for 15 metabolites has been achieved taking advantage of the mass accuracy and resolving power of UHR-TOF MS as well as using our previously published results [21,26]. The identification of these analytes has been corroborated by using analytical standards and also an available GC-APCI-TOF MS database [25]. ...
In order to investigate avocado fruit ripening, nontargeted GC-APCI-TOF MS metabolic profiling analyses were carried out. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used to explore the metabolic profiles from fruit samples of 13 varieties at two different ripening degrees. Mannoheptulose; pentadecylfuran; aspartic, malic, stearic, citric and pantothenic acids; mannitol; and β-sitosterol were some of the metabolites found as more influential for the PLS-DA model. The similarities among genetically related samples (putative mutants of "Hass") and their metabolic differences from the rest of the varieties under study have also been evaluated. The achieved results reveal new insights into avocado fruit composition and metabolite changes, demonstrating therefore the value of metabolomics as a functional genomics tool in characterizing the mechanism of fruit ripening development, a key developmental stage in most economically important fruit crops.
... Epicatechin was the only flavonoid quantified in the present study, and its highest content was found in Spanish fruits (27.82 ± 17.48 mg kg −1 DW). This average concentration is similar to previous results for fruits of the same variety reported by Hurtado-Fernández and colleagues and Serrano-García and co-authors [28,34]. High standard deviation values for this compound were observed for all geographical origins. ...
Spain dominates avocado production in Europe, with the Hass variety being the most prominent. Despite this, Spanish production satisfies less than 10% of the overall avocado demand in Europe. Consequently, the European avocado market heavily relies on imports from overseas, primarily sourced from Peru and Chile. Herein, a comprehensive characterization of the metabolic profile of Hass avocado fruits from Spain, Peru, and Chile, available in the European market throughout the year, was carried out. The determination of relevant substances was performed using high- and low-resolution RP-LC-MS. Remarkable quantitative differences regarding phenolic compounds, amino acids, and nucleosides were observed. Principal component analysis revealed a natural clustering of avocados according to geographical origin. Moreover, a specific metabolic pattern was established for each avocado-producing country using supervised partial least squares discriminant analysis. Spanish fruits exhibited high levels of coumaric acid malonyl-hexose II, coumaric acid hexose II, and ferulic acid hexose II, together with considerably low levels of pantothenic acid and uridine. Chilean avocado fruits presented high concentrations of abscisic acid, uridine, ferulic acid, succinic acid, and tryptophan. Fruits from Peru showed high concentrations of dihydroxybenzoic acid hexose, alongside very low levels of p-coumaric acid, ferulic acid, coumaric acid malonyl-hexose I, and ferulic acid hexose II.
... The band at 2900 cm −1 corresponded to the CH2 and CH 3 groups, attributed to C-H asymmetric and symmetric stretching (Affes et al., 2020). A strong band in the 3338-3252 cm −1 region in BC corresponds to N-H and O-H stretching as well as intramolecular hydrogen bonds (Hurtado-Fernández et al., 2014). ...
Chitosan is a mucoadhesive and natural biodegradable polysaccharide derived by the deacetylation of chitin, such as an interesting biopolymer to form films and coatings for food preservation. The objective of this work was to isolate and characterize the structural and physicochemical properties of biochemical chitosan (BC) from shrimp (Litopenaeus vannamei) exoskeletons such as to develop an active film based on BC, native bean (Phaseolus polyanthus) starch (BS), and quercetin (Q). Further, the antioxidant activity and in vitro release tests were evaluated and compared with commercial chitosan (CC)- commercial tapioca starch (TS)-Q control film. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy of BC were used to calculate the crystallinity index (58.91%) and deacetylation degree (88.45%), respectively. Also, the zeta (ζ) potential and solubility values of the stock solution of BC were 45.72 mV and 99.86% at pH 4.0, respectively. The BCBS Q film presented the highest release of Q in simulated foods in ethanol solutions at 50% and 95% concentrations, which could be used as an active packaging film both in oil-in-water emulsions and fatty foods with potential antioxidant activity.
... The extraction time and temperature might be the factors that caused higher results. In previous studies, the concentration of flavonoids tended to decrease as the fruit progressively ripened [29]. ...
Avocados (Persea americana M.) are highly valued fruits consumed worldwide, and there are numerous commercially available varieties on the market. However, the high demand for fruit also results in increased food waste. Thus, this study was conducted for comprehensive profiling of polyphenols of Hass, Reed, and Wurtz avocados obtained from the Australian local market. Ripe Hass peel recorded the highest TPC (77.85 mg GAE/g), TTC (148.98 mg CE/g), DPPH (71.03 mg AAE/g), FRAP (3.05 mg AAE/g), RPA (24.45 mg AAE/g), and ABTS (75.77 mg AAE/g) values; unripe Hass peel recorded the highest TFC (3.44 mg QE/g); and Wurtz peel recorded the highest TAC (35.02 mg AAE/g). Correlation analysis revealed that TPC and TTC were significantly correlated with the antioxidant capacity of the extracts. A total of 348 polyphenols were screened in the peel. A total of 134 compounds including 36 phenolic acids, 70 flavonoids, 11 lignans, 2 stilbenes, and another 15 polyphenols, were characterised through LC-ESI-QTOF-MS/MS, where the majority were from peels and seeds of samples extract. Overall, the hierarchical heat map revealed that there were a significant amount of polyphenols in peels and seeds. Epicatechin, kaempferol, and protocatechuic acid showed higher concentrations in Reed pulp. Wurtz peel contains a higher concentration of hydroxybenzoic acid. Our results showed that avocado wastes have a considerable amount of polyphenols, exhibiting antioxidant activities. Each sample has its unique value proposition based on its phenolic profile. This study may increase confidence in utilising by-products and encourage further investigation into avocado by-products as nutraceuticals.
... Pacchiarotta, Mayboroda, Fernández-Gutiérrez, & Carrasco-Pancorbo, 2014). Throughout the maturation process in the tree or softening in the cold chamber, the quantitative evolution of epicatechin was not clear, so it was not possible to establish a clear pattern. ...
When the recipient of the product is relatively distant from the production area, it is necessary to use cold storage and controlled humidity to transport the avocado fruits. One of the main advantages of local avocado consumption lies on the possibility of prolonging on-tree maturation; this could foreseeably modify the metabolic profile of the fruit which arrives to the consumer. In this work, the effect of prolonged on tree maturation (during different time intervals) on the final composition of avocado fruit (at edible ripeness) was evaluated and compared with the impact of the same periods after prolonged cold storage. The quantitative evolution of nine bioactive metabolites (7 phenolic compounds, pantothenic and abscisic acids) over 40 days (10-days intervals) was studied by using a solid-liquid extraction protocol and a LC-MS methodology. The results were discussed both considering the quantitative evolution of each individual compound and the sum of all of them.
... Other studies focusing on APGC ionization used derivatization with BSTFA and/or MSTFA on analytes such as amino acids, phenolic acids, glycolysis intermediates, flavonoids, fatty acids, and anabolic androgenic steroids. 17,[19][20][21]23,25 In all studies, the protonated derivatized analyte was considered as the [M + H] + ion and minimal in-source fragmentation was reported for most of the analytes. However, the fragment ions formed corresponded to a loss of a derivatization group, demonstrating that derivatization acts as a stabilizer and suppresses in-source fragmentation of the actual analyte. ...
Hop essential oil is a mixture of several hundred volatile metabolites that quantitatively and qualitatively distinguish hop varieties. Given the commercial relevance of hops in the brewing industry and the complexity of hop oil, analytical tools enabling a comprehensive characterization of oil constituents are required. At this, atmospheric pressure chemical ionization interfaced to gas chromatography and high-resolution mass spectrometry (APGC–MS) is a promising option that combines soft ionization, high sensitivity, and high resolution. While high sensitivity is required to detect minor or trace-level volatile metabolites, soft ionization and high resolution enable the reliable identification of unknowns based on exact masses of the molecular ion or the protonated molecule. Twenty-two volatile metabolites typically found in hop oil were studied in respect to their APGC ionization behavior. For 15 compounds, APGC–MS did not yield high molecular ion or protonated molecule intensities and considerable in-source fragmentation was observed. APGC–MS parameter optimization (cone gas flow and cone voltage) was able to yield the maximum absolute intensity for the base peak. However, in-source fragmentation could not be prevented, leading to spectra with either the protonated molecule or a characteristic fragment ion as the base peak. APGC–MS operated under optimized parameters was applied to a hop essential oil sample to verify the effect of optimization. By estimating the limit of quantification for the 22 compounds, it is concluded that APGC–MS is well suited to analyze major, minor, and trace-level volatiles from hops.
... Avocado mesocarp is rich in oil (15-30 g per 100 g), mainly consisting of monounsaturated fatty acids with oleic (the main fraction) linoleic, palmitoleic and linolenic acids in decreasing order of abundance (Bergh, 1992;Meyer & Terry, 2010). Its nutritional value is also associated with other nutrients, such as vitamins, minerals, dietary fibre, phenolic compounds, carotene, thiamin, phytosterols and phytostanols, seven-carbon sugars, resveratrol and proteins (Hurtado-Fernández, Pacchiarotta, Mayboroda, Fernández-Gutiérrez, & Carrasco-Pancorbo, 2014). Among them, phenolic compounds, which originate from secondary plant, vegetable and fruit metabolism, including avocado, are the main dietary sources with wellknown physiological benefits (Lima et al., 2019). ...
This study investigated the capability of selected autochthonous lactic acid bacteria to enrich the portfolio of bioactive compounds of avocado fruit (Persea americana Mill.), with the perspective of producing dietary supplements or pharmaceutical preparations. Fermented avocado puree resulted in high levels of total free amino acids. Fermentation also led to a marked increase of antioxidant activity, with the highest levels found in water and hexane soluble extracts. Bio-converted phenolic compounds and fatty acids derivatives resulting from bacterial metabolism were likely responsible for the increased antioxidant activity. Fermentation caused the fortification of avocado puree with some hydroxy fatty acids, which deserved marked attention due to their health-promoting activities. Oleic and linoleic acids were highly metabolized by Lactobacillus plantarum AVEF17, leading to high levels of mono, di-, and tri-hydroxy-octadecenoic acids.
... 5,7,13,14 Lipit içeriğinin yanı sıra avokado, diğer meyvelerin aksine (diğer meyvelerde genellikle %1 oranında protein içerir) %2 oranında protein içermesi; vitamin (özellikle B, E ve C vitaminleri), potasyum, magnezyum, fosfor, pigment (antosiyaninler (siyanidin-3-O-glikozit), klorofiller ve karotenoitler (-karoten, -karoten, kriptoksantin, lutein, izlolutein zeaksantin ve türevleri), sterol, fenolik bileşikler, yedi karbonlu şeker ve bununla ilgili alkoller (D-mannoheptuloz ve perseitol) içermesi sebebiyle de oldukça dikkat çekicidir. 5,[13][14][15][16][17][18][19] Avokado meyvesi, içerdiği sağlığa yararlı maddeler sebebiyle çeşitli bağımsız kuruluşlarca "sağlıklı meyve" olarak sertifikalandırılmış, ve günlük diyette tüketilmesi tavsiye edilmiştir. 13 ...
Persea americana meyveleri (avokado), 1500'lü yılların başlarına kadar sadece Amerika yerlileri tarafından tüketilirken, Amerika Kıtası'nın keşfiyle Avrupa tarafından tanınmış, sonrasında da tüm dünyaya yayılmıştır. Ülkemizde, meyvelerin besin olarak tüketiminin yaygınlaşması ve ticari önem kazanması son yıllarda artış göstermiştir, ancak bitkinin kültüre alınması 1980'li yıllara dayanmaktadır. Günümüzde, özellikle Antalya, Mersin ve Hatay bölgelerinde P. americana türünün birkaç varyetesi yetiştirilmektedir. İçerdiği mineraller (özellikle potasyum), vitaminler (özellikle E ve C vitaminleri), protein, fitosteroller ve yağ asitleriyle zengin bir kaynak olan avokado üzerinde yapılmış birçok çalışma bulunmaktadır. Yapılan in vitro çalışmalar, yaprak ekstrelerinin anti-HIV, sitotoksik ve insektisidal etkiye; çekirdek yağının gastroprotektif, antihelmintik ve antioksidan etkiye; meyvenin ise antibakteriyel etkiye sahip olduğunu göstermektedir. Bu çalışma ile P. americana türünün kimyasal bileşimi, tıbbi etki ve kullanılışı üzerine yapılmış araştırmaların derlenmesi, Türkiye'de yetişen varyetelerin öneminin vurgulanması ve tıbbi potansiyelinin değerlendirilmesi amaçlanmıştır. Elde edilen bulgular Akdeniz bölgemizin toprak ve iklim koşullarının içerik açısından zengin bitkiler yetişmesine uygun olduğunu, bu bitkinin tıbbi açıdan değerlendirilmesi için ileri çalışmaların yapılması gerektiğini göstermektedir. ABSTRACT Persea americana (Avocado) fruits were consumed by only Native Americans until early 1500's, while Europe was recognized by the discovery of the America Continent and then spread all over the world. In Turkey, widespread consumption of the fruits as nutrients and gaining commercial importance have increased in recent years, but the cultivation of the plant dates back to the 1980s. Today, several varieties of P. americana species are cultivated, especially in Antalya, Mersin, and Hatay. There are many studies reveal that avocado is a rich source of minerals (especially potassium), vitamins (especially vitamins E and C), protein, phytosterols and fatty acids. In vitro studies have shown that the leaf extracts of P. americana have anti-HIV, cytotoxic and insecticidal effects; the seed oil has gastroprotective, antihelminthic and antioxidant effects; the fruit has antibacterial effect. The study aims to review the research studies on the chemical composition, medicinal effect and usage of P. americana, and also to determine and emphasize the medicinal potential of the cultivated species in Turkey. The findings of this study indicate that the soil and climatic conditions of the Mediterranean region are suitable for the growth of P. americana with rich content, and further studies are needed for the medical evaluation of this plant.
... 5,7,13,14 Lipit içeriğinin yanı sıra avokado, diğer meyvelerin aksine (diğer meyvelerde genellikle %1 oranında protein içerir) %2 oranında protein içermesi; vitamin (özellikle B, E ve C vitaminleri), potasyum, magnezyum, fosfor, pigment (antosiyaninler (siyanidin-3-O-glikozit), klorofiller ve karotenoitler (-karoten, -karoten, kriptoksantin, lutein, izlolutein zeaksantin ve türevleri), sterol, fenolik bileşikler, yedi karbonlu şeker ve bununla ilgili alkoller (D-mannoheptuloz ve perseitol) içermesi sebebiyle de oldukça dikkat çekicidir. 5,[13][14][15][16][17][18][19] Avokado meyvesi, içerdiği sağlığa yararlı maddeler sebebiyle çeşitli bağımsız kuruluşlarca "sağlıklı meyve" olarak sertifikalandırılmış, ve günlük diyette tüketilmesi tavsiye edilmiştir. 13 ...
Persea americana meyveleri (avokado), 1500’lü yılların başlarına kadar sadece Amerika yerlileri tarafından tüketilirken, Amerika Kıtası’nın keşfiyle Avrupa tarafından tanınmış, sonrasında da tüm dünyaya yayılmıştır. Ülkemizde, meyvelerin besin olarak tüketiminin yaygınlaşması ve ticari önem kazanması son yıllarda artış göstermiştir, ancak bitkinin kültüre alınması 1980’li yıllara dayanmaktadır. Günümüzde, özellikle Antalya, Mersin ve Hatay bölgelerinde P. americana türünün birkaç varyetesi yetiştirilmektedir. İçerdiği mineraller (özellikle potasyum), vitaminler (özellikle E ve C vitaminleri), protein, fitosteroller ve yağ asitleriyle zengin bir kaynak olan avokado üzerinde yapılmış birçok çalışma bulunmaktadır. Yapılan in vitro çalışmalar, yaprak ekstrelerinin anti-HIV, sitotoksik ve insektisidal etkiye; çekirdek yağının gastroprotektif, antihelmintik ve antioksidan etkiye; meyvenin ise antibakteriyel etkiye sahip olduğunu göstermektedir. Bu çalışma ile P. americana türünün kimyasal bileşimi, tıbbi etki ve kullanılışı üzerine yapılmış araştırmaların derlenmesi, Türkiye’de yetişen varyetelerin öneminin vurgulanması ve tıbbi potansiyelinin değerlendirilmesi amaçlanmıştır. Elde edilen bulgular Akdeniz bölgemizin toprak ve iklim koşullarının içerik açısından zengin bitkiler yetişmesine uygun olduğunu, bu bitkinin tıbbi açıdan değerlendirilmesi için ileri çalışmaların yapılması gerektiğini göstermektedir.
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Persea americana (Avocado) fruits were consumed by only Native Americans until early 1500’s, while Europe was recognized by the discovery of the America Continent and then spread all over the world. In Turkey, widespread consumption of the fruits as nutrients and gaining commercial importance have increased in recent years, but the cultivation of the plant dates back to the 1980s. Today, several varieties of P. americana species are cultivated, especially in Antalya, Mersin, and Hatay. There are many studies reveal that avocado is a rich source of minerals (especially potassium), vitamins (especially vitamins E and C), protein, phytosterols and fatty acids. In vitro studies have shown that the leaf extracts of P. americana have anti-HIV, cytotoxic and insecticidal effects; the seed oil has gastroprotective, antihelminthic and antioxidant effects; the fruit has antibacterial effect. The study aims to review the research studies on the chemical composition, medicinal effect and usage of P. americana, and also to determine and emphasize the medicinal potential of the cultivated species in Turkey. The findings of this study indicate that the soil and climatic conditions of the Mediterranean region are suitable for the growth of P. americana with rich content, and further studies are needed for the medical evaluation of this plant.
Key words: Persea americana, avocado, history, ethnobotanical uses, chemical composition, biological activities
... Moreover, most of these studies have reported significant positive correlations between the phenolic compounds and antioxidant capacity of avocado extracts [84][85][86][87][88]. Phenolic compounds found in avocado were shown to reduce oxidation, inflammation, and platelet aggregation [65]. Several studies have reported that different parts of the avocado plants contain potent phenolic antioxidants such as chlorogenic-, quinic-, succinic-, pantothenic-, abscisic-, ferulic-, gallic-, sinapinic-, p-coumaric-, gentisic-, protocatechuic-, 4-hydroxybenzoic-, and benzoic-acids, quercetin, quercetin-3-glucoside, quercetin-3-rhamnoside, vanillin, p-coumaroyl-D-glucose, catechins, (−)-epicatechin, and procyanidins (Table 3) [2,28,84,[89][90][91][92][93][94][95][96][97]. Among the different parts of avocado investigated in several studies, leaf, peel, and seed extracts have shown consistently greater antioxidant capacity compared to that of the pulp [84,91,94,[96][97][98][99][100][101][102][103][104][105][106]. ...
Persea americana, commonly known as avocado, has recently gained substantial popularity and is often marketed as a "superfood" because of its unique nutritional composition, antioxidant content, and biochemical profile. However, the term "superfood" can be vague and misleading, as it is often associated with unrealistic health claims. This review draws a comprehensive summary and assessment of research performed in the last few decades to understand the nutritional and therapeutic properties of avocado and its bioactive compounds. In particular, studies reporting the major metabolites of avocado, their antioxidant as well as bioavailability and pharmacokinetic properties, are summarized and assessed. Furthermore, the potential of avocado in novel drug discovery for the prevention and treatment of cancer, microbial, inflammatory, diabetes, and cardiovascular diseases is highlighted. This review also proposes several interesting future directions for avocado research.
... To date, many of these effects have not been clearly demonstrated, but inferred based on the chemical composition of avocados, which has not been completely determined yet. The aim of this work was the systematical analysis of the health-protective effects, both objectively regarded to avocado fruit, as well as those inferred from the : Duester, 2001;Liu et al., 2002;Piironen et al., 2003;Lu et al., 2005;Ashton et al., 2006;Cerretani et al., 2010;Meyer and Terry 2010;Hurtado-Fernández et al., 2011;Villa-Rodríguez et al., 2011;Yahia and Woolf, 2011;Berasategi et al., 2012;Blakey et al., 2012;Hurtado-Fernández et al., 2014;Rodríguez-López et al., 2015;López-Cobo et al., 2016. 156 chemical composition of avocados. ...
Mexico is the largest producer, exporter and consumer of avocados (Persea americana Mill) in the world. The demand for this fruit in some non-producing countries is currently high. The main motivation for this fruit’s consumption is its exquisite taste and pleasant texture. However, recent research has suggested that this fruit can exert protective effects on human health, as empirically determined centuries ago by the inhabitants of pre-Hispanic Mexico. These effects have been attributed to the high content of health-related compounds, including unsaturated fatty acids, acetogenins, phytosterols, tocopherols, tocotrienols, carotenoids, chlorophylls, phenols, organic acids and sugars of seven carbons. Avocado is one of the few fruits in the human diet with a high content of both water-soluble and fat-soluble health-related compounds. The main protective effects attributed to avocados include the prevention of cardiovascular diseases, diabetes and some forms of cancer, which are diseases considered in many countries as public health problems. Unfortunately, there is little research demonstrating the protective effects of avocados on human health. The aim of this work was the systematical analysis of the health-protective effects, both objectively regarded to avocado fruit, as well as those inferred from the avocado chemical composition.
... PCA has previously been used to analyze Py-GC-MS data, mostly in alternative fuels [19,20] and some other applications [6,21]. PCA has been previously used for GC-APCI data interpretation in metabolomics [22] and food chemistry applications [23,24]. This work represents the first application of Py-GC-dAPCI-TOF to the study of the monomers of complex polymers while using PCA and in-source CID. ...
Polyurethane is one of the most widely used copolymers and is formed by the cross-linking of isocyanates and polyols. Its physical properties have a strong dependence on the monomer structures, making it very important to characterize the monomers in polyurethane. In this study, we developed a method to analyze unknown polyurethane samples using pyrolysis gas chromatography time-of-flight mass spectrometry (Py-GC-TOFMS) with dopant-assisted atmospheric pressure chemical ionization (dAPCI). A set of standard polyurethane foams produced with several different monomers are analyzed by Py-GC-TOFMS. GC-dAPCI-TOFMS is a high-resolution, soft ionization method for GC-MS analysis that provides accurate mass information of GC separated molecules. The data obtained by this approach could effectively classify different monomers using principal component analysis (PCA), grouping polymers with the same monomers, and providing structural features significant to each monomer. Furthermore, characteristic compounds are identified using in-source collision-induced dissociation (CID) and CSI:FingerID analysis. In contrast, the same set of samples analyzed by Py-GC-electron ionization (EI)-MS could only partially separate some of the monomers.
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... Against this background, a facile analytical method is of primary importance to ensure the sufficiency of FA in foods. Previously, high-performance liquid chromatography (HPLC) has been extensively used (León-Ruiz et al. 2013;Hurtado-Fernández et al. 2014;Gliszczyńska-Świgło et al. 2015;Morales et al. 2015; La Barbera et al. 2017;Ulusoy et al. 2017). With particular concern on the reliability of methods, mass spectrometry is generally used in combination (Cellar et al. 2016). ...
This paper proposes a facile and specific method tailored for quantifying and confirming folic acid in food, based on the combination of high-performance thin layer chromatography with fluorescence densitometry and surface-enhanced Raman spectroscopy. Chromatography was carried out on silica gel plates, using methanol/ethyl acetate/ammonia (6:4:1, v/v/v) as the mobile phase. For the first time, ozone gas was utilized as the derivative agent, which efficiently induced the appearance of strong fluorescence of the analyte. Thereafter, fluorescent densitometry measurements were carried out for quantitative purpose, offering good linearity (R² > 0.999) and sensitivity (0.7–1.4 mg/kg). In addition, the applicability and reliability of the established method was validated with food and food supplement samples, showing good agreement with the data obtained by conventional HPLC-UV as the benchmark, but with remarkably higher efficiency. Apart from that, the in situ-obtained surface-enhanced Raman spectroscopic fingerprint of bands under optimized conditions (532-nm incident laser and tenfold concentrated silver nanoparticles) enabled unambiguous identification of the targeted compound, serving as a convenient and affordable tool to prevent potential mistake from false-positive results.
... The lowest content of pyrogallol observed in control and prochloraz-treated fruit could be to some extent explained by pyrogallol being used as a substrate by PPO and peroxidase (POD), leading to tissue browning as indicated by higher chilling index, 17,50 especially taking into account the high affinity of PPO for pyrogallol. The content of p-coumaric acid and ferrulic acid, which usually increase during fruit ripening, 51 was not affected by the treatments, suggesting that fruit were likely at the same ripeness stage. ...
Background:
Low temperature is often used to reduce metabolic processes and extend the storage of fruit, however, in the case of avocado the temperature below 3 °C would often result in development of physiological disorders associated with chilling injury. The objective of this study was to investigate the ability of methyl jasmonate (MeJA) and methyl salicylate (MeSA) vapours to alleviate the chilling injury in 'Hass' avocado fruit kept at 2 °C for 21 d followed by 6-7 d shelf-life at 20 °C, simulating supply chain conditions.
Results:
The incidence and severity of chilling injury was significantly reduced in MeJA and MeSA exposed fruit, especially at 100 µmol l(-1) . The mechanism involved improved membrane integrity via alteration of the fatty acids content and composition, down-regulation of LOX gene expression and reduced activity of lipoxygenase.
Conclusion:
Methyl jasmonate and methyl salicylate have the potential for being used with 'Hass' avocado fruit shipped at low temperature by reducing their susceptibility to chilling injury.
... Against this background, a facile analytical method is of primary importance to ensure the sufficiency of FA in foods. Previously, high-performance liquid chromatography (HPLC) has been extensively used (León-Ruiz et al. 2013;Hurtado-Fernández et al. 2014;Gliszczyńska-Świgło et al. 2015;Morales et al. 2015; La Barbera et al. 2017;Ulusoy et al. 2017). With particular concern on the reliability of methods, mass spectrometry is generally used in combination (Cellar et al. 2016). ...
Background:
Over the years, germinated adlay products have been used as both food source and folk medicine. This study investigated the changes of total phenolic content (TPC), total flavonoid content (TFC), antioxidant activities, and phenolic acid profiles of adlay seed during germination.
Results:
Results revealed that phenolic compounds and antioxidant activities varied with the germination stages. Germination significantly increased the free form phenolic and flavonoid contents by 112.5% and 168.3%, respectively. However, both of the bound form phenolic and flavonoid contents significantly decreased after germination. Phenolic acid compositions were quantified via HPLC analysis, and the levels of vanillic, p-coumaric, caffeic, hydroxybenzoic, and protocatechuic acids in the free phenolic extracts were found to significantly increased. The improvement of the free and total phenolic and flavonoid contents by the germination process led to a significant enhancement of the antioxidant activities (evaluated by ABTS, FRAP, and ORAC). The TPC showed the highest correlation with ORAC values (r=0.9979).
Conclusion:
Germinated adlay had higher free and total phenolic and flavonoid contents, and antioxidant activities than ungerminated adlay. This study indicates that germinated adlay could be a promising functional food, more suitable for human consumption.
... It is possible to address that our aim was doubled: (1) to establish the concentration levels of the metabolites under study for the four selected varieties and (2) to check whether the trend was similar in all the evaluated varieties, considering the evolution of the six metabolites quantified. Different reasons motivated the quantification of the aforementioned compounds; some of the most important are as follows: their commercial Hurtado-Fernández et al. 2014); the fact that they are produced by the phenylpropanoid pathway, which seems to have an important role in fruit maturity and ripening (Singh et al. 2010); and, last but not least, the viability of carrying out their proper quantification avoiding problems related to the dead volume of the column or possible matrix effects. ...
Herewith, a longitudinal study where the metabolic evolution of six relevant metabolites (p-coumaric, ferulic, chlorogenic, pantothenic and abscisic acids, and epicatechin) in four commercially important avocado varieties collected at different times over their harvest season is presented with the aim of evaluating the metabolic changes that take place during fruit development and maturation. The selection of these metabolites was based on the fact that they have been previously identified as potential varietal and/or ripening markers of avocado fruits and are produced by the phenylpropanoid pathway. Avocado metabolic profiles can be highly variable within a system, showing variations even from day to day. Thus, a longitudinal study design was selected to overcome possible negative effects of this variability on the interpretation of data, considering multiple sampling over time. A powerful HPLC-ESI-IT MS method was optimized and fully validated, and subsequently, a very unique sample selection (composed by 172 avocado extracts) was analyzed and the selected metabolites quantified. The content of pantothenic, p-coumaric, and ferulic acids was quite similar in the four avocado varieties studied. However, epicatechin, chlorogenic, and abscisic acid concentrations showed significant differences; ‘Bacon’ was the cultivar with the highest content of chlorogenic acid, ‘Hass’ and ‘Bacon’ of epicatechin, and ‘Fuerte’ and ‘Reed’ were the richest in terms of abscisic acid.
... Hurtado-Fernández et al. (2015) investigated GC-APCI-TOF capacity in order to understand the fruit-ripening mechanism, since avocado's external appearance is not accompanied by changes during ripening. The analytical method was previously optimised for this purpose (Hurtado-Fernández et al. 2014), and at the same time the method was even compared with the GC-EI-MS approach . In this research, solid-liquid extraction using methanol and derivatisation (N,O-bis(trimethylsilyl) trifluoroacetamide with 1% trimethylchlorosilane (BSTFA + 1% TMCS) was performed prior to acquiring GC-APCI-TOF fingerprints. ...
Food authenticity becomes a necessity for global food policies, since food put on market has to be without fail authentic. It has always been a challenge, since in the past time minor components, called also markers, have been mainly monitored by chromatographic methods in order to authenticate the food. Nevertheless, nowadays, advanced analytical methods have allowed food fingerprints to be achieved. At the same time they have been also combined with chemometrics, which uses statistical methods in order to verify food and to provide maximum information by analysing chemical data. These sophisticated methods based on different separation techniques or stand-alone have been recently coupled to high-resolution mass spectrometry (HRMS) in order to verify the authenticity of food. The new generation of HRMS detectors has experienced significant advances in resolving power, sensitivity, robustness, extended dynamic range, easier mass calibration and tandem mass capabilities, making HRMS more attractive and useful to food metabolomics community, therefore, becoming a reliable tool for food authenticity. The purpose of this review is to summarise and describe the most recent metabolomics approaches in the area of food metabolomics, and to discuss strengths and drawbacks of the HRMS analytical platforms combined with chemometrics.
Consumer priorities in healthy diets and lifestyle boosted the demand for nutritious and functional foods as well as plant‐based ingredients. Avocado has become a food trend due to its nutritional and functional values, which in turn is increasing its consumption and production worldwide. Avocado edible portion has a high content of lipids, with the pulp and its oil being rich in monounsaturated fatty acids and essential omega − 3 and omega − 6 polyunsaturated fatty acids (PUFA). These fatty acids are mainly esterified in triacylglycerides, the major lipids in pulp, but also in minor components such as polar lipids (phospholipids and glycolipids). Polar lipids of avocado have been overlooked despite being recently highlighted with functional properties as well. The growth in the industry of avocado products is generating an increased amount of their byproducts, such as seed and peels (nonedible portions), still undervalued. The few studies on avocado byproducts pointed out that they also contain interesting lipids, with seeds particularly rich in polar lipids bearing PUFA, and thus can be reused as a source of add‐value phytochemical. Mass spectrometry‐based lipidomics approaches appear as an essential tool to unveil the complex lipid signature of avocado and its byproducts, contributing to the recognition of value‐added lipids and opening new avenues for their use in novel biotechnological applications. The present review provides an up‐to‐date overview of the lipid signature from avocado pulp, peel, seed, and its oils.
Avocados (Persea americana) are a unique fruit that can provide health benefits when included in a healthy diet. As health care moves towards precision health and targeted therapies or preventative medicine, it is critical to understand foods and their dietary components. The nutritional composition and plant physiology of the Hass avocado is strikingly different from other fruits. This paper reviews the nutrient and bioactive composition of the edible portion of the Hass avocado (pulp) reported in the literature and from commercial lab analyses of the current market supply of fresh Hass avocados. These results provide comprehensive data on what nutrients and bioactives are in avocado and the quantity of these nutrients. We discuss the reasons for nutrient composition variations and review some potential health benefits of bioactive compounds found in Hass avocados.
A simple flame-induced atmospheric pressure chemical ionization (FAPCI) source was developed to couple a gas chromatograph (GC) with a mass spectrometer (MS). The interface consisted of a heated transfer line and a high voltage-free ambient FAPCI source. Nitrogen gas flowing through the heated transfer line was utilized to deliver the analytes eluted from a GC column to the ionization region. A micro oxyacetylene flame was positioned under the exit of heated transfer line, which generated primary charged species in the ionization region. Since the temperature at the ionization region was below 200 °C, the analytes were not thermally decomposed. Protonated analytes were formed by reacting the analytes with flame-induced charged species through ion-molecule reactions (IMRs). The simple GC-FAPCI/MS was used to characterize a series of fatty acid methyl esters (FAMEs) and long-chain normal alkanes, which showed protonated FAME and oxidized n-alkane ions on the mass spectra. The limits of detection (LODs) for C15:0 to C25:0 FAMEs were 1–2.5 pg. A calibration curve ranging from 2.5 to 500 pg, with a R² value of 0.9821, was obtained.
Tarihte birçok farklı isimle anılan avokado (Persea americana Mill), Amerika'dan gelen tropikal bir meyvedir. En büyük üreticisi Meksika olup günümüzde birçok farklı ülkede üretimi yapılmaktadır. Ülkemizdeki avokado üretimi de hızla artmaktadır ve üretim son 19 yılda 14 kat artarak 2019 yılında 4209 tona ulaşmıştır. Yüksek besin içeriği ve sağlığa yararlı etkilerinin yanı sıra tıbbi amaçlar için de yetiştirilen bu meyve birçok araştırmacının odak noktası olmuştur. Avokado yapısında yüksek düzeyde (ortalama %15) yağ içeren nadir meyvelerden biridir ve yağın bileşimi zeytinyağı ile büyük benzerlik göstermektedir. Bunun yanında, meyve, farklı yağ asitleri, vitaminler, mineraller, karotenoidler ve diğer fitokimyasallar gibi temel besinler açısından oldukça zengin bir bileşime sahiptir. Yapılan araştırmalarda, avokadonun yapısında bulunan biyoaktif bileşiklerin antimikrobiyal, antiinflamatuvar, antikanser, antidiyabetik ve antihipertansif gibi sağlığa yararlı etkileri olduğu ve özellikle kolesterolü düşürmede ve kardiyovasküler hastalıkları önlemede avokado tüketiminin önemli olduğu ifade edilmektedir. Tüm bu yararlı etkileri nedeniyle avokadonun son 10 yılda üretimi ve günlük diyette tüketimi önemli ölçüde artmıştır. Bu derlemede avokadonun tarihçesi, çeşitleri, üretimi, bileşimi ve içerdiği biyoaktif bileşenlerin sağlığa etkileri ele alınmıştır.
Fruit juices are becoming more and more popular in the whole world. However, the increasing fruit juice fraud cases are undermining the healthy development of fruit juice industry. Fruit juice authenticity represents an important food quality and safety parameter. Many techniques have been applied in fruit juices authenticity assessment. The purpose of this review is to provide a research overview of the targeted and untargeted analyses of fruit authentication, and a method selection guide for fruit juice authenticity assessment. Targeted markers, such as stable isotopes, phenolics, carbohydrates, organic acids, volatile components, DNAs, amino acids and proteins, as well as carotenoids, will be discussed. And untargeted techniques, including liquid/gas chromatography-mass spectrometer, nuclear magnetic resonance, infrared spectroscopy, inductively-coupled plasma-mass spectrometry/optical emission spectrometer, fluorescence spectra, electronic sensors and others, will be reviewed. The emerging untargeted for novel targeted marker analysis will be also summarized.
Diets rich in phenolic compounds have been associated to reducing the risk of metabolic syndrome and its derived disorders. Fruits are healthy components of the human diet because of their vitamin, mineral, fiber and phenolic profile. However, they have a short shelf-life which is limited by microbiological growth and enzymatic activity. Innovative preservation methods such as high hydrostatic pressure, pulsed electric fields, ultrasound, microwave, cold plasma and ultraviolet light have become popular for the processing of fruits because they can preserve nutritional quality. In this review, the phenolic profile and health potential of 38 Mesoamerican fruits were assessed. Phenolic compounds were classified based on their contribution to the diet as flavonoids, phenolic acids, tannin, lignins and stilbenoids. Due to this composition, fruits showed a wide range of bioactivities which included anti-inflammatory, anti-diabetic, anti-hypertensive and anti-obesity activities, among others. Phenolic content in fruits submitted to innovative food processing technologies depended on parameters such as enzymatic activity, antioxidant capacity, microstructure integrity and cell viability. Innovative technologies could increase phenolic content while assuring microbiological safety by (i) promoting the release of bound phenolic compounds during processing and (ii) inducing the synthesis of phenolic compounds by activation of phenylpropanoid pathway during storage.
Polyphenols are one of the most numerous and ubiquitous groups of phytochemicals in the plant kingdom. They are present in fruit and vegetables, as well as in food ingredients such as pigments, essences and flavors, and thus, they are usually consumed as part of our diet. In recent years, they have gained relevance as a consequence of the discovery of their beneficial effects on health. The aim of this chapter is to provide information on the analytical determination of these important substances, paying particular attention to their extraction, separation, and detection by chromatographic, electrophoretic, and spectroscopic techniques. The number of applications in this field is large so this chapter does not set out to be exhaustive but to illustrate the state of the art and to address and describe some representative reports published in recent years.
Avocado (Persea americana Mill.), originated in Mexico and Central America, is the only commercial important edible fruit that belongs to Lauraceae family. This fruit shows a growing value on the international market, not only for of its nutritional quality, but also due to its medicinal uses and application in the cosmetic industry. Fruit constituents revealed that it abounds in various fatty acids, protein, vitamins, and minerals. Besides this, a lot of secondary metabolites have also been isolated from different parts of the avocado plant. The predominant carotenoid is lutein, but other carotenoids are also described, including α-carotene, β-carotene, zeaxanthin, neoxanthin and violaxanthin. It has been reported that these lipophilic carotenoids may have, among others, potential anti-carcinogenic effects. This fruit has been recognized for its health benefits, especially due to the compounds present in the lipidic fraction, such as omega fatty acids, phytosterols, tocopherols and squalene. Several studies have shown the benefits of avocado associated to a well-balanced diet, especially in reducing cholesterol and preventing cardiovascular diseases. The processed avocado pulp is an alternative to utilize this fruit, which can be used in various value-added food products.
Tocopherols have also been identified not only in avocado pulp fruits but in their seeds. For these reasons, the recovery of health beneficial bioactive compounds from fruit and its wastes is a current research trend not only to help minimize the waste burden, but also to meet the intensive consumer demand for bioactive compounds which are believed to have protective effects against chronic diseases.
Avocado pulp and seed contain variable oil content and is widely used in the pharmaceutical and cosmetic industries, as well as in the production of commercial oils similar to olive oil. It contains fatty acids such as lignoceric acid, arachidic acid, margaric acid, behenic acid, gadolenic acid, docosadienoic, myristic and eicosanoic acids, β-sitosterol, lecithin, minerals, and vitamins, showing its potential as an alternative dietary supplement.
This book covers a wide variety of topics related to avocado’s latest research such as nutritional value and characterization, polyphenolic compounds recovery from avocado fruits and their wastes (peel and seeds) as an excellent alternative for industry, especially, for pulp processing or oil extraction, considering its composition and beneficial health compounds. Furthermore, this crop can be used for exportation and oil extraction, application in processed products, or as raw material in the pharmaceutical and cosmetic industries, generating high value-added products.
Keywords: Persea americana Mill; Nutraceutics; Bioactive compounds; Therapeutic properties; By-products; Sustainability.
Atmospheric pressure chemical ionization (APCI) has been commercially implemented in gas chromatography mass spectrometry (GC-MS) instruments within the past decade and is becoming an important complementary tool to traditional GC-electron impact (EI) ionization-MS and liquid chromatography MS (LC-MS) for quantitative and nontarget screening purposes. APCI is a soft ionization technique, so more molecular ions and/or protonated molecules are present than when the traditional EI source is implemented, improving the sensitivity and selectivity of analytical methods. Moreover, this state-of-the-art apparatus facilitates the identification of chemicals not contained in commercial libraries. In this review, parameters inside and outside the APCI source could influence the sensitivity of the analysis are discussed. Trends towards improvement of APCI source and combination with multidimensionality further improve the quantitative and qualitative analysis of GC-MS. Finally, the applications of GC-APCI-MS, especially in nontarget studies are addressed.
O interesse pelo reaproveitamento das diferentes partes das frutas e dos vegetais tem vindo a aumentar, não só com o intuito de promover a sustentabilidade ambiental, como também pelas demais propriedades benéficas que têm sido reconhecidas pela comunidade científica. O teor em compostos bioativos das sementes de mamão, que são quase sempre desperdiçadas, levou ao estudo de usos alternativos das mesmas. Neste âmbito, quantificou-se o teor de compostos não-nutritivos das sementes da Carica papaya L., nomeadamente, fenólicos e flavonoides totais, avaliando-se também a atividade antioxidante das mesmas. Apesar das evidências de que as sementes de mamão podem ser utilizadas como antioxidantes naturais, nas indústrias alimentar e farmacêutica, torna-se necessário aprofundar a investigação no sentido de avaliar a toxicidade das mesmas.
The aim of this study was to relate the untargeted and targeted metabolites to the number of days taken to reach ‘ready-to-eat stage’ ripeness based on firmness and incidence of anthracnose in five avocado cultivars (‘Hass,’ ‘Lamb Hass,’ ‘Pinkerton,’ ‘Fuerte,’ and ‘Ryan’) harvested at different growing seasons (early, mid and late season). Cultivar ‘Ryan,’ harvested at early and mid-seasons, took longer (7 days) to ripen and showed the lowest incidence of anthracnose, whilst cv. ‘Fuerte’ ripened faster (4 days) and showed the highest incidence of anthracnose. UPLC-MS, together with principal component analysis, demonstrated clear groupings of the samples according to their cultivars. Major heterogeneity in the untargeted metabolome profile was observed in cv. ‘Ryan.’ Supervised Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) approach showed a unique biomarker ([M−H]⁻_ 17.48 at m/z 331.23 (Laricitrin) separated cv. ‘Ryan’ from the other cultivars. Different growing seasons of cv. ‘Hass’ were separated based on unidentified markers [early ([M−H]⁻_17.62 at m/z 420.31), mid ([M−H]⁻_18.48 at m/z 325.18) and late ([M−H]⁻_9.90 at m/z 329.23)]. Targeted metabolites including C7D-mannoheptulose, skin epicatechin, ferulic, p-coumaric, chlorogenic, caffeic, (-)-L-chicoric, caftaric, palmitic (16:0), oleic (18:1) and linoleic (18:2) acids contents and antioxidant activities were highest in cv. ‘Ryan’ at ready-to-eat stage irrespective of the seasons. Thus, cv. ‘Ryan’ could be a useful candidate for the avocado oil industry due to its higher fatty acid composition. The higher concentration of unsaturated fatty acids and C7D-mannoheptulose at ready-to-eat stage in cv. ‘Ryan’ avocados provides health benefits. The observed reduction in anthracnose decay in cv. Ryan avocados was attributed to the higher concentration of epicatechin in the skin and the pool of phenolic metabolites in the mesocarp.
The influence of regular air cold storage (7 °C and 85 ± 5% RH) followed by ripening at shelf‐life conditions (19–21 °C and 65 ± 5% RH), on bioactive compounds of Hass avocados was investigated. Results showed that the content of mannoheptulose and perseitol decreased significantly already during cold storage and ripening period. The fatty acid profile and contents of tocopherols (α‐ and β‐tocopherol) and phytosterols (β‐sitosterol, stigmasterol, campesterol) remained unchanged from day 0 to edible ripeness. Total phenolics, hydrophilic and lipophilic antioxidant capacity remained unchanged during cold storage and increased during the ripening period. At edible ripeness, significant amounts of phenolic acids, p‐coumaric and caffeic and their derivatives were synthesised. Our results demonstrated that regular air cold storage for up to 37 days followed by ripening at shelf‐life conditions enhances the phenolic compounds and mainly the hydrophilic antioxidant capacity without affecting the remaining bioactive compounds in Hass avocado.
Acquired Immune Deficiency Syndrome is the most severe phase of Human Immunodeficiency Virus (HIV) infection. Recent studies have seen an effort to isolate phytochemicals from plants to repress HIV, but less studies have focused on the effects of these phytochemicals on the activities of enzymes/transporters involved in the metabolism of these drugs, which is one of the aims of this study and, to examine the antiviral activity of these compounds against HIV-1 protease enzyme using computational tools. Centre of Awareness-Food Supplement (COA®-FS) herbal medicine, has been said to have potential anti-HIV features. SWISSTARGETPREDICTION and SWISSADME servers were used for determination of the enzymes/transporters involved in the metabolism of these protease inhibitor drugs, (PIs) (Atazanavir, Lopinavir, Darunavir, Saquinavir) and the effects of the selected phytochemicals on the enzymes/transporters involved in the metabolism of these PIs. Using Computational tools, potential structural inhibitory activities of these phytochemicals were explored. Two sub-families of Cytochrome P450 enzymes (CYP3A4 and CYP2C19) and Permeability glycoprotein (P-gp) were predicted to be involved in metabolism of the PIs. Six phytochemicals (Geranin, Apigenin, Fisetin, Luteolin, Phthalic acid and Gallic acid) were predicted to be inhibitors of CYP3A4 and, may slowdown elimination of PIs thereby maintain optimal PIs concentrations. Free binding energy analysis for antiviral activities identified four phytochemicals with favourable binding landscapes with HIV-1 protease enzyme. Epigallocatechin gallate and Kaempferol-7-glucoside exhibited pronounced structural evidence as potential HIV-1 protease enzyme inhibitors. This study acts as a steppingstone toward the use of natural products against diseases that are plagued with adverse drug-interactions.
Fourier transform mass spectrometry (FTMS) is widely used to characterise the chemical complexity of mixtures, such as natural organic matter (NOM), petroleum, and agri-food products (including Scotch Whisky). Although electrospray ionisation (ESI) is by far the most widely used ionisation source in these studies, other ionisation techniques are available and may offer complimentary information. In a recent study, we found matrix free laser desorption/ionisation (LDI) to be effective for the analysis of Suwannee River fulvic acid (SRFA), and to provide complementary chemical insights. In this study, LDI along with Atmospheric Pressure Photoionisation (APPI) and Atmospheric Pressure Chemical Ionisation (APCI) were compared to ESI for the analysis of Scotch Whisky. High mass accuracy (54 ppb, mean) allowed for assignment of 86% of peaks, with 3993 unique molecular formulas identified from four representative samples analysed. All four ionisation techniques, performed in negative mode, identified thousands of formulas. Many were unique to each ionisation source, whilst 699 formulas were common to all techniques. Ions were identified in both deprotonated and radical anion forms. Our study highlights the importance of a multi ionisation source approach; we recommend that analysis of complex mixtures, especially novel ones, should not be limited solely to ESI.
The physicochemical composition of avocado fruit has been well reported, but there is little detail on Chinese native avocado varieties. The present study investigated the morphological characteristics, oil contents, and fatty acid compositions of 16 avocado accessions grown in the tropical and subtropical regions of China. Eight fatty acids were identified and quantified by GC-MS. The major fatty acids of avocado pulp were palmitic, oleic, and linoleic acids, accounting for 78-91% of the total fatty acids content. The analysis of one-way variance (ANOVA) of the data revealed morphological and chemical differences between most of avocado accessions. Moreover, 16 avocado accessions were distinguished through a PCA scores scatter plot and cluster analysis based on fatty acid profiles. The results identified some remarkable characteristics of avocado accessions from different places of collection.
We studied the morphological characteristics, nutritional quality, and the bioactive compounds in fruits of two avocado accessions, RN-7 and RN-8, produced in Hainan province, China. Edible and non-edible parts of the fruit (pulp and seed) were compared to evaluate their possible contribution to improve the sustainability of the food and pharmaceutical industries. The basic characteristics evaluated were moisture, ash, total lipid, fatty acid composition, soluble sugars, titratable acid, soluble protein, and minerals. We also measured the concentrations of six types of bioactive compounds; total phenolics, flavonoids, tannin, ascorbic acid, tocopheryl acetate, and carotenoids. Our analyses of the nutritional compositions demonstrated that the pulp of the RN-7 and RN-8 proved to be rich in moisture, total lipid, and soluble protein. The seed, in turn, had higher soluble sugar, titratable acidity, sodium, potassium, calcium, iron, copper, and zinc contents. Other nutritional compositions (ash, magnesium, and manganese) had little differences between the pulp and seed of avocado fruit. With regard to the contents of bioactive compounds, the seed was superior to the pulp in the contents of total phenolics, flavonoids, and tannin. Regarding the concentrations of ascorbic acid, tocopheryl acetate, and total carotenoids, the highest values were found in the pulp. The results of fatty acid compositions displayed that the palmitic, palmitoleic, stearic, oleic, and linoleic acid contents of the pulp were higher than those of the seed, while myristic and arachic acid had higher contents in the seed.
The phenolic profiles of six varieties of Avocado (Persea americana) grown in Sicily were investigated. UHPLC-HESI-MS method was developed to determine qualitative and quantitative changes in fruits at two different ripening stage. Nineteen individual phenolic compounds were detected in avocado pulp extracts. Gallic acid, sinapinic acid, vanillin, p-coumaric acid and gentisic acid were present only in ripe fruits. On the contrary, epicatechin decreased with fruit ripening, whereas protocatechuic acid, 4-hydroxybenzoic acid, chlorogenic acid, and benzoic acid were relatively stable or exhibited erratic changes with fruit ripening. The different avocado cultivars exhibited different phenolic profiles and total quantities and it was found that, among the tested cultivars, 'Orotawa' avocados may provide the highest nutritional and health contribution to human diet. The qualitative and quantitative differences among cultivars and maturation stages by multivariate analysis allowed for the individuation of a set of phenolic compounds that have a great potential in the discrimination and identification of different genetic groups.
Until recently, analytical methods for food safety and quality control had mainly been focused on restricted lists of well-known analytes. Nowadays, in addition to these classical methods, comprehensive analysis attains authentication as well as the detection of hazardous or safety-relevant manipulations and violations of the laws (e.g., addition of nonauthorized substances or application of technological processes prohibited is of urgent need in food control). This chapter shows that high resolution mass spectrometry (HRMS) associated with the data mining tools developed for metabolomics can address this issue by enabling (1) targeted analyses, (2) detection of untargeted and unknown compounds, and (3) detection of metabolites useful for the characterization of food matrices. After a brief outline of several well-established and emerging HRMS techniques, covering from mass sectors to imaging mass spectrometry, the current performance and applications of these approaches in food quality and safety are presented.
Urinary tract infection (UTI) is among the most common bacterial infections worldwide. The understanding of the physiological mechanisms affected by UTI may need modern integrative ‘–omics’ technologies, and metabolomics in particular. Here we present the first GC-APCI-MS-based explorative metabolomics study of UTI, using MS and FID detectors simultaneously. This provides high quality mass spectral data as well as semi-quantitative information demonstrating the feasibility of the GC-APCI-MS platform for non-targeted approach. The work is part of a bigger project aiming at providing a comprehensive overview of UTI-induced changes in urine. Taking advantage of a fully clinically characterized cohort that offers the possibility of both case-control and longitudinal modelling, we can define UTI-induced change as a list of urinary metabolites which distinguish E. coli UTI patients from the subjects with no signs of an active infection. The list of molecular descriptors includes compounds related to bacterial activity such as lactic acid and lactose while other molecules show an association with the physiological status (inositol, citric acid).
In the version of this article initially published, in the Reagent Setup section, it was stated that 50% v/v Percoll should be made by diluting Percoll in 10× PBS at a 1:1 v/v ratio. Percoll should, in fact, be diluted in 2× PBS at a 1:1 ratio. The error has been corrected in the HTML and PDF versions of the article. In the version of this article initially published, a component (40 μl of 50 mg ml –1 BSA) was erroneously omitted from the 'Hybridization solution' recipe in the Reagent Setup section. The error has been corrected in the HTML and PDF versions of the article.
Method validation is one of the measures universally recognized as a necessary part of a comprehensive system of quality assurance in analytical chemistry. In the past, ISO, IUPAC, and AOAC International have cooperated to produce agreed protocols or guidelines on the "Design, conduct and interpretation of method performance studies" [1], on the "Proficiency testing of (chemical) analytical laboratories" [2], on "Internal quality control in analytical chemistry laboratories" [3], and on "The use of recovery information in analytical measurement" [4]. The Working Group that produced these protocols/guidelines has now been mandated by IUPAC to prepare guidelines on the single-laboratory validation of methods of analysis. These guidelines provide minimum recommendations on procedures that should be employed to ensure adequate validation of analytical methods.
A draft of the guidelines has been discussed at an International Symposium on the Harmonization of Quality Assurance Systems in Chemical Laboratory, the proceedings from which have been published by the UK Royal Society of Chemistry.
Dry matter, oil content and fatty acid composition of avocado fruit (Persea americana, cv. Fuerte and Hass) were examined with respect to the harvesting and post-harvest ripening period. Fruits were harvested in November, December, and January at one-month intervals. Samples were kept for 8 days under ambient conditions to ripen. Dry matter and oil content of both cultivars increased significantly (p < 0.05) according to the length of time that the fruits remained on the tree. However, significant (P < 0.05) changes in the amount of dry matter and oil content of avocado were determined during the post-harvest ripening period. There were significant (p < 0.05) differences in the fatty acid compositions of Fuerte and Hass in each sampling time. Although oleic acid significantly (p < 0.05) increased with late harvest, other fatty acids decreased. In particular, palmitic acid notably underwent a 46.5% decrease from November to January. There were statistically significant (p < 0.05) differences in the fatty acid compositions during the post-harvest ripening period: however, these were too small numerically to be of significance, either biologically or nutritionally.
Avocado ( Persea americana Mill.) fruit from various locations in California were analyzed for oil and subjected to taste tests every 2 weeks throughout the fruiting season over a period of 5 years. Oil content at acceptable taste differed among cultivars, and the 8% requirement was too low to serve as a good maturity standard for many cultivars. While the date of acceptable taste of fruit grown at the same location was not significantly different from year to year, it varied significantly among and within the widespread avocado production areas. Dry weight, which was highly correlated with increasing oil content, was evaluated as a maturity index. The dry-weight analysis with a microwave oven was much easier than determining oil content. The average dry weight at 8% oil (the existing legal standard in California) was 19.4% for ‘Bacon’, 19.1% for ‘Fuerte’, 19.8% for ‘Hass’, 18.9% for ‘Pinkerton’, and 18.4% for ‘Zutano’ fruit. Dry weight at acceptable taste was 20.0% for ‘Bacon’, 21.0% for ‘Fuerte’, 22.8% for ‘Hass’, 20.0% for ‘Pinkerton’, and 20.2% for ‘Zutano’.
The aim of this study was to determine physical and chemical changes during fruit development and their relationship with optimum harvest maturity for Bacon, Fuerte and Zutano avocado cultivars grown under Dörtyol ecological condition. Fruits cv. Bacon, Fuerte and Zutano were obtained trees grafted on seedlings and planted 5 m x 6 m in Dörtyol Research Station of Faculty of Agriculture, Mustafa Kemal University. Fruit width and length, weight, skin and flesh color (L* and hue), total soluble solid (TSS), titratable acidity (TA), TSS/TA, fruit flesh firmness, juice pH, dry weight and oil content were measured on fruits samples collected from tagged trees from June drop to ripening at a 15 days interval during fruit development. Data indicated that oil and dry matter content, flesh firmness and fruit weight were important criteria in determining optimum harvest maturity. Based on the all criteria, the period from the end of November to middle of December was the optimum harvest time for these cultivars in order to deliver fruit at optimum commercial maturity and quality and to obtain adequate storage time.
Abstract Background Avocados contain monounsaturated fatty acids (MUFA) dietary fiber, essential nutrients and phytochemicals. However, no epidemiologic data exist on their effects on diet quality, weight management and other metabolic disease risk factors. The objective of this research was to investigate the relationships between avocado consumption and overall diet quality, energy and nutrient intakes, physiological indicators of health, and risk of metabolic syndrome. Methods Avocado consumption and nutrition data were based on 24-hour dietary recalls collected by trained NHANES interviewers using the USDA Automated Multiple Pass Method (AMPM). Physiological data were collected from physical examinations conducted in NHANES Mobile Examination Centers. Diet quality was calculated using the USDA’s Healthy Eating Index-2005. Subjects included 17,567 US adults ≥ 19 years of age (49% female), including 347 avocado consumers (50% female), examined in NHANES 2001–2008. Least square means, standard errors, and ANOVA were determined using appropriate sample weights, with adjustments for age, gender, ethnicity, and other covariates depending on dependent variable of interest. Results Avocado consumers had significantly higher intakes of vegetables (p
Introduction. Pomegranate fruit is a good source of bioactive compounds. Although data about the importance of pomegranates in human nutrition has increased extensively in the last years, the fruit physical and chemical characteristics of some Iranian pomegranate cultivars during fruit ripening have not been investigated in detail yet. Therefore, the evaluation of physicochemical characteristics of pomegranate fruit cv. 'Rabbab-e-Fars' at three different stages, from fruit set to ripening, was the aim of the present study. Materials and methods. Fruit fresh weight and volume, and peel, aril, juice and seed percentage were measured as physical features and total soluble solids, pH, titrable acidity, ascorbic acid, total sugars, anthocyanins, phenolics and tannins, condensed tannins, and antioxidant activity in the juice were evaluated as the chemical properties. Results. The highest percentage of aril (57.86%) and juice (48.01%) and lowest percentage of peel (42.13%) and seed (10.49%) were observed in 140-day-old fruits. A significant increase in concentrations of total soluble solids and total sugars were recorded during fruit ripening. The ascorbic acid content decreased significantly, while the amount of total anthocyanins increased significantly with fruit maturity. Ripe fruit, which had a low titratable acidity (1.35 g.100 g(-1) of fruit juice), showed a correspondingly high pH (3.23). The levels of total phenolics, total tannins, condensed tannins and antioxidant activity declined significantly during fruit ripening. Conclusion. Our results provide important information on the changes in physical and chemical properties of pomegranate fruit during ripening, which is very useful for determination of the fruit quality.
A better understanding of the post-harvest physiology of avocado (Persea americana Mill.) fruit is required to improve the post-harvest management of the crop. Two heptoses, D-mannoheptulose and perseitol, occur in unusually high concentrations in avocado tissues and are thought to be important in fruit ripening. We determined changes in the concentrations and relationships between individual sugars, total soluble proteins, and oil during fruit ripening. ‘Hass’ fruit were harvested from cool and warm sub-tropical areas in South Africa three-times during a single season. Dry matter increased during the season at both locations. For fruit from the cool sub-tropical climate, D-mannoheptulose and perseitol concentrations declined rapidly from 15.9 mg g-1 dry weight (DW) and 7.9 mg g-1 DW to 2.1 mg g-1 DW and 0.6 mg g-1 DW, respectively, 13 d after harvest. Overall concentrations of glucose and fructose were negligible at harvest and increased to 1.4 mg g-1 DW and 0.8 mg g-1 DW, respectively, during ripening. The concentration of glucose in fast-ripening fruit increased 3 d prior to increasing in slow-ripening fruit. The concentration of sucrose was intermediate (2.8 – 4.5 mg g-1 DW) and was variable during ripening. The concentration of total soluble proteins increased during ripening from 17.8 mg g-1 DW to 34.8 mg g-1 DW, whereas the concentration of oil was fairly stable during ripening, and varied from 24.8 – 36.7% DW, depending on fruit maturity. It is suggested that the heptose pool is an important source of carbon and/or energy in avocado fruit. The low concentrations of these sugars and the rapid decline in their levels, post-harvest, indicate that optimal post-harvest management, especially cold storage and ripening temperature regimes, is necessary to reduce the risk of post-harvest disorders and to ensure a consistent supply of high-quality avocado fruit.
The effect of harvest date on nutritional compounds and antioxidant activity (AOC) in avocado (Persea americana Mill. cv Hass) fruit during storage was determined. The fruits were harvested at seven different dates and ripened at 25 °C following 21 or 35 days of cold storage. The results indicated that the phenolic and glutathione contents were increased and the ascorbic acid content was not significantly different in early harvested fruit (January to March), and the phenolic, ascorbic acid and glutathione contents were increased slightly and then decreased on late harvested fruit (April to June). Similar trends were observed in the changes of AOC. Furthermore, AOC in early harvested fruit after storage for 35 days was much higher than that in late harvested fruit after storage for 21 days. Therefore, avocado can be harvested earlier for economic benefits according to the market and can keep high nutritional value for human health benefits.
Tomato is an important crop in terms of its economic and nutritional value. Tomato fruit quality is a function of metabolite content, which is prone to physiological changes related to fruit development and ripening. The aim of this work was to use a metabolomic approach to characterize compositional changes (sugars, acids and amino acids) of tomato during preharvest fruit development, ripening, and postharvest shelf-life. Gas chromatography–mass spectrometry was used to identify both polar and volatile metabolites that were involved in fruit development and ripening. Characteristic metabolites for the various fruit developmental stages were identified. Mannose, citramalic, gluconic and keto-l-gulonic acids were shown to be strongly correlated to final postharvest stages. During on-vine ripening, an increase was observed for the major hexoses, glucose and fructose, cell wall components such as galacturonic acid, and for amino acids such as aspartic, glutamic acid and methionine. Major changes were also observed at the level of the TCA cycle, showing a decrease in malic and fumaric acids, and accumulation of citric acid.Highlights► Biochemical changes during preharvest and postharvest life of tomato fruit were characterized. ► Potential marker metabolites to characterize tomato storage life were identified. ► Major changes were observed at the level of the TCA cycle during on-vine ripening ► Changes were related to organoleptic and nutritional values of the fruit. ► Mannose, citramalic, gluconic and keto-l-gulonic acids were characterized during storage.
Over the past decades, herbal medicine has become a thing of global significance with medicinal and economic implications. Wide spread use of herbs throughout the globe has raised serious concerns over its quality, safety, and efficacy. Thus, exact scientific assessment has become a precondition for acceptance of herbal health claims. Persea americana Mill. (avocado) is a tree, native to central America, cultivated in tropical and subtropical climates around the world, belonging to the family Lauraceae, is widely used in Ayurveda and evidence-based phototherapy. There are 3 principal races or groups of avocado: Mexican, Guatemalan, and West Indian named for the areas where they were originally cultivated. The plant is used in traditional medicine for the treatment of various ailments, such as monorrhagia, hypertension, stomach ache, bronchitis, diarrhea, and diabetes. Peptone, b-galactoside, glycosylated abscisic acid, alkaloids, cellulose, polygalacto urease, polyuronoids, cytochrome P-450, and volatile oils are reported to be present in this plant. Biotechnologic approaches show that modified MS medium supplemented with 1.0 mg benzyladenine/L, 0-1mg Indole Butyric Acid/L, 0.1 mg Gibberalic Acid 3/L was optimum for adventitious shoot development. In the present review, an effort has been made to study the different aspects of P. americana Mill.
ABSTRACT During avocado fruit ripening, decreasing levels of the flavonoid epicatechin have been reported to modulate the metabolism of preformed antifungal compounds and the activation of quiescent Colletotrichum gloeosporioides infections. Epicatechin levels decreased as well when C. gloeosporioides was grown in the presence of epicatechin in culture. Extracts of laccase enzyme obtained from decayed tissue and culture media fully metabolized the epicatechin substrate within 4 and 20 h, respectively. Purified laccase protein from C. gloeosporioides showed an apparent MW of 60,000, an isoelectric point at pH 3.9, and maximal epicatechin degradation at pH 5.6. Inhibitors of fungal laccase such as EDTA and thioglycolic acid reduced C. gloeosporioides symptom development when applied to ripening susceptible fruits. Isolates of C. gloeosporioides with reduced laccase activity and no capability to metabolize epicatechin showed reduced pathogenicity on ripening fruits. On the contrary, Mexican isolates with increasing capabilities to metabolize epicatechin showed early symptoms of disease in unripe fruits. Transcript levels of cglac1, encoding C. gloeosporioides laccase, were enhanced during fungal development in the presence of epicatechin at pH 6.0, where avocado fruits are susceptible to fungal attack. But transcript increase was not detected at pH 5.0, where the fruit is resistant to fungal attack. The present results suggest that biotransformation of epicatechin by C. gloeosporioides in ripening fruits is followed by the decline of the preformed antifungal diene compound, resulting in the activation of quiescent infections.
The concept of metabolite profiling has been around for decades, but technical innovations are now enabling it to be carried out on a large scale with respect to the number of both metabolites measured and experiments carried out. Here we provide a detailed protocol for gas chromatography mass spectrometry (GC-MS)-based metabolite profiling that offers a good balance of sensitivity and reliability, being considerably more sensitive than NMR and more robust than liquid chromatography-linked mass spectrometry. We summarize all steps from collecting plant material and sample handling to derivatization procedures, instrumentation settings and evaluating the resultant chromatograms. We also define the contribution of GC-MS-based metabolite profiling to the fields of diagnostics, gene annotation and systems biology. Using the protocol described here facilitates routine determination of the relative levels of 300-500 analytes of polar and nonpolar extracts in approximately 400 experimental samples per week per machine.
This IUPAC nomenclature document has been prepared to help establish a uniform and meaningful approach to terminology, notation, and formulation for performance characteristics of the Chemical Measurement Process (CMP). Following definition of the CMP and its Performance Characteristics, the document addresses fundamental quantities related to the observed response and calibration, and the complement to the calibration function: the evaluation function. Performance characteristics related to precision and accuracy comprise the heart of the document. These include measures for the means or ''expected values” of the relevant chemical quantities, as well as dispersion measures such as variance and standard error. Attention is given also to important issues involving: assumptions, internal and external quality control, estimation, error propagation and uncertainty components, and bounds for systematic error. Special treatment is given to terminology and concepts underlying detection and quantification capabilities in chemical metrology, and the significance of the blank. The document concludes with a note on the important distinction between the Sampled Population and the Target Population, especially in relation to the interlaboratory environment.
Yellow flesh peaches (Prunus persica L.) from different Sicilian areas (Leonforte, Riesi and Maniace) were investigated for the first time for their polyphenolic composition, with consideration of both peel and flesh tissues. The qualitative and quantitative polyphenolic evaluation was determined at two different maturity stages (commercial and postharvest ripening) via chromatographic separation by using reverse-phase HPLC-PDA-ESI/MS 2. This technique provides a comprehensive chromatographic evaluation of 10 compounds (hydroxycinnamates and flavonols), differently distributed in the analyzed tissues. Overall, the hydroxycinnamates were present in both pulp and peel, while flavonols resulted exclusively located in the peel. Peels were found to be richest in polyphenolics with respect to the pulps, containing up to 276 mg/kg fresh weight in Riesi commercial-ripe peaches. Generally, the peach tissues from commercial-ripe fruits showed higher phenolics contents than postharvest-ripe fruits.
It is well documented that the benefits due to the consumption of fruit can be largely attributed to the elevated content of phenolic compounds. High levels of phenolic compounds in fruits are of high importance to maintain the quality of fruits and provide consumers the health benefits of fruit consumption. Thus, the assessment of the distribution of phenolic compounds in various parts of the peach fruit and any variations due at the time of collection are considered interesting from a scientific point of view. The characterization of peach phenolics could represent a useful tool in the area of food authenticity protection since some compounds could represent specific quality markers. Moreover, a study on phenolics quantification at different ripening stages could provide useful information for assessing the fruit harvest timing in order to ensure the best fruit quality.
A CZE method with two different MS detection conditions (MRM and Full Scan) was developed to determine qualitative and quantitative changes in the metabolic profile of avocado fruits (Persea americana). LODs in MRM approach were found between 20.1 and 203.0 ppb for abscisic acid and perseitol, respectively, whilst in Full Scan, varied within the range 0.22–1.90 ppm for the same metabolites. The RSDs for reproducibility test did not exceed 11.45%. The two MS approaches were used to quantify 10 metabolites (phenolic acids, flavonoids, a carbohydrate, an organic acid, a vitamin and a phytohormone) in 18 samples of avocado at different ripening states, and the achieved results were compared. Perseitol, quinic, chlorogenic, trans-cinnamic, pantothenic and abscisic acids, as well as epicatechin and catechin decreased during the ripening process, whereas ferulic and p-coumaric acids showed the opposite trend. Moreover, some other unknown compounds whose concentration changed largely during ripening were also studied by MS/MS and QTOF MS to get a tentative identification.
Changes in aroma volatiles were determined using solid phase microextraction (SPME) and gas chromatography/mass spectrometry in ripe avocados (Persea americana Mill., cv. Hass) throughout an eight-month maturation period and related to the sensory properties of the fruit. As maturation progressed sensory panelists found the likeability of the fruit to increase, coinciding with the fruit becoming creamier and less watery in texture, and the flavor richer and less grassy. During this maturation time the concentration of hexanal, (E)-2-hexenal and 2,4-hexadienal, three of the most abundant volatiles, greatly declined in amount. These volatiles all have a grass-like aroma, and it is likely that the loss in amount was responsible for the decline in grassy flavor during maturation. Acetaldehyde, methyl acetate, pentanal, and β-myrcene were at higher concentrations in mature than non-mature fruit and may also have contributed to the overall flavor. Avocados of an intermediate maturity were ripened at 20 °C and fruit of different ripeness levels (firmnesses) measured for ethylene production, rate of respiration and aroma volatile content. A sharp increase in the rates of respiration and ethylene production marked a rapid increase in softening and the beginning of the climacteric. Twenty-five volatiles were identified in the ripening avocados of which three (pentanol, hexanol, and 2-nonenal) were not detectable in fully-ripe fruit. Of particular interest was an 85% decline in the amount of hexanal in a comparison of firm to fully ripe (4 N firmness) fruit. Aroma volatiles have in the past been little-studied in avocados but appear to have a role in determining the flavor of the fruit.
Although GC-APCI-MS was developed more than 40 years ago this coupling is still far from being a routine technique. One of the reasons explaining the limited use of GC-APCI so far is the lack of spectral database which facilitates the identification of the compounds under study. The first application of a very recently developed GC-APCI database to identify as many compounds as possible in a complex matrix such as avocado fruit is presented here. The results achieved by using this database has been checked against those obtained using traditional GC-EI-MS and a comparison of the MS signals observed in both ionization sources has been carried out. 100 compounds belonging to different chemical families were identified in the matrix under study. Considering the results of this study, the wide range of application (in terms of polarity and size of analytes) and the robustness of APCI as interface, the high quality of TOF spectra, and our library as a publicly available resource, GC-APCI-TOF MS is definitively a valuable addition to the "metabolomics toolbox".
Herein we present the development of a powerful CE-UV method able to detect and quantify an important number of phenolic acids in 13 varieties of avocado fruits at 2 ripening stages. All the variables involved in CE separation were exhaustively optimized and the best results were obtained with a capillary of 50μm i.d.×50cm effective length, sodium tetraborate 40mM at a pH of 9.4, 30kV, 25°C, 10s of hydrodynamic injection (0.5psi) and UV detection at 254nm. This optimal methodology was fully validated and then applied to different avocado samples. The number of phenolic acids determined varied from 8 to 14 compounds; in general, they were in concentrations ranging from 0.13ppm to 3.82ppm, except p-coumaric, benzoic and protocatechuic acids, which were found at higher concentrations. Principal component analysis (PCA) was applied to highlight the differences between varieties and ripening degrees, looking for the most influential analytes.
This study reports on the effect of 1-methylcyclopropene (1-MCP) and a newly developed palladium (Pd)-promoted ethylene scavenger (e+® Ethylene Remover) on changes in firmness, colour, fatty acids and sugar content of early and late season avocado (Persea americana Mill.), cv. Hass, during storage at 5°C and subsequent ripening at 20°C. The e+® Ethylene Remover effectively delayed ripening of avocado stored at 5°C. 1-MCP was more effective at inhibiting ripening, but, in contrast to e+® Ethylene Remover, it impaired subsequent ripening. Fatty acid profile of late season fruit remained unchanged in response to treatments or storage time, whilst that of early season fruit was slightly, yet significantly, different according to treatments and storage time. Substantial amounts of perseitol were found in all fruit. In contrast, mannoheptulose was only present at high concentration in early season fruit whilst it was quasi-absent in late season fruit. Where ripening was inhibited in response to 1-MCP treatment, significantly more mannoheptulose and better maintenance of perseitol was found vs. controls. Similarly, but to a lesser extent and concomitant with trends in firmness retention and colour changes, e+® Ethylene Remover led to greater maintenance of mannoheptulose and perseitol than that of controls. This is the first piece of research comparing effects of ethylene removal vs. ethylene action blocking on physical and biochemical changes in avocado cv. Hass and supports the view that C7 sugar metabolism could be an important feature of the avocado fruit-ripening process.
In this study a simultaneous determination of several classes of phytochemicals (isoflavones, glucosinolates, flavones, flavonols and phenolic acids) in tomato, broccoli, carrot, eggplant and grape has been carried out by ultra high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Solid-liquid extraction assisted by rotary agitator was utilised, using a mixture of methanol:water (80:20, v/v) as solvent. The analytical procedure was validated in all the matrices, obtaining recoveries ranging from 60% to 120% with repeatability values (expressed as relative standard deviations, RSDs) lower than 25%. Limits of quantification (LOQs) were always equal or lower than 50μg/kg, except for some glucosinolates (125μg/kg). Finally the method was applied to different matrices such as tomato, broccoli, carrot, grape and eggplant, observing that chlorogenic acid was detected in most of the samples at higher concentrations in relation to the other compounds.
IT has been found that the electrical conductivity of a flame burning a
mixture of hydrogen and nitrogen (in air) is very sensitively affected
by the vapours of organic substances, and this effect can be used for
detection purposes in gas chromatography.
Total phenolic concentrations as gallic acid equivalents were determined for leaves, fruits (mesocarp), and seeds (cotyledons) of several cultivated varieties of avocado (Persea americana Mill.). Concentrations were generally highest in cotyledons and lowest in the mesocarp of fruits. Phenolic acids were extracted by alkaline hydrolysis and identified with high-performance liquid chromatography, spectrophotometry, and thin-layer chromatography. Sixteen phenolic acids were identified, and in general, every tissue of every variety had the same array. The commonly occurring gentisic acid was not detected.
The capabilities of a recently launched atmospheric pressure chemical ionization (APCI) source for mass spectrometry (MS) coupled to gas chromatography (GC) have been tested in order to evaluate its potential in pesticide residue analysis in fruits and vegetables. Twenty-five pesticides were selected due to their high fragmentation under electron ionization (EI), making that the molecular ion (M(+)) is practically absent in their spectra. The fragmentation of these pesticides under APCI conditions was studied, with the result that M(+) was not only present but also highly abundant for most compounds, with noticeable differences in the fragmentation patterns in comparison with EI. Moreover, the addition of water as modifier was tested to promote the formation of protonated molecules ([M+H](+)). Under these conditions, [M+H](+) became the base peak of the spectrum for the majority of compounds, thus leading to an increase of sensitivity in the subsequent GC-MS/MS method developed using triple quadrupole analyzer (QqQ). Highly satisfactory sensitivity and precision, in terms of repeatability, were reached and linearity was satisfactory in the range 0.01-100ng/mL. The developed methodology was applied to apple, orange, tomato and carrot QuEChERS fortified extracts in order to evaluate the matrix effects. In summary, the soft and reproducible ionization in the APCI source has greatly favored the formation of [M+H](+) oppositely to EI where abundant fragmentation occurs and where the molecular ions have low abundance or are even absent in the mass spectrum. In this way, the use of APCI has facilitated the development of tandem MS methods based on the selection of abundant [M+H](+) as precursor ion.
The effect of ripening on the chemical characteristics of fruits of the avocado (Persea americana) cultivars Ettinger, Fuerte and Hass was investigated. A study of some quality parameters of these main avocado cultivars grown on the island of Crete was performed. As the fruit ripened, a decrease in the moisture content was observed, with a high degree of correlation for all the cultivars. At the same time an increase in the fat and protein contents was measured. The content of total sugars was high in the unripe fruit but decreased during ripening. The fatty acid composition of the oil extracted from the fruit pulp was determined by gas chromatographic analysis. The oil of the edible portion of the fruit was rich in oleic, palmitic, linoleic and palmitoleic acids, while stearic acid was present in small quantities. During the ripening process the amount of palmitic acid decreased and that of oleic acid increased in all the cultivars. The ratio of polyunsaturated to saturated fatty acids, which is considered as an indicator of the nutritional value of the fruit, was also calculated. No significant differences were observed between the cultivars. Principal component analysis was also performed to examine the relationship among the quality variables of the cultivars. From these data, Fuerte was considered to be the cultivar with the best characteristics. Copyright © 2004 Society of Chemical Industry
The aim of this investigation was to determine the nutritional and bioactive properties of relatively less investigated exotic fruit durian (Durio zibethinus Murr.) and to compare these indices with widely used mango (Mangifera indica L.) and avocado (Persea americana). For this purpose HPLC, three-dimensional fluorescence (3D-FL), several radical scavenging assays and multivariate factor analysis were used. It was found a similarity in acetone extracts between durian and mango in the contents of polyphenols (1.66 ± 0.08, 1.48 ± 0.05, mg GAE g−1 DW, respectively), and in some antioxidant assays such as ABTS (11.98 ± 0.5, 12.24 ± 0.5, μm TE g−1DW, respectively) and DPPH (5.61 ± 0.3, 5.22 ± 0.2, μm TE g−1 DW, respectively). Durian and avocado were similar in the contents of polyphenols, and ABTS and DPPH values in water and in methanol extracts, respectively. Based on the obtained results the nutritional and bioactive properties of durian are comparable with those indices in mango and avocado. In conclusion, durian can be recommended as a part of disease prevented diets.
Centrifugal force separation is a relatively new industrial process for extracting avocado oil. This study examined the influences
of temperature, pH and NaCl concentration on oil extraction efficiency by centrifugal processing. Optimal separation conditions
occurred at 75 C, with a pH of 5.5 and NaCl concentration of 5%.
Differences in chemical characteristics exist between avocado oils produced by industrial processes and those oils that were
produced in the laboratory by organic solvent extraction. The highest amount of chlorophyll, 192.9 ppm, was obtained by ethanolic
extraction in the laboratory. Unsaponifiables content reached 1.95% in industrial oil produced by organic solvent extraction.
The highest acid value, 8.35, was obtained from industrial oil produced by centrifugal separation. Hydroxyl values in our
oils were found to be 2–3 times higher than those reported in the literature.
The phenolic profile and quantitative composition of blueberries as well as the corresponding antioxidant activity of blueberries is well documented. Unfortunately, little is reported on the development of phenolic compounds and antioxidant activity during fruit maturation and ripening. In the present study, the total phenolic content and main phenolic compounds of four highbush blueberry cultivars (Vaccinium corymbosum L.) were analyzed at five stages of maturation and ripening. Antioxidant activity was screened with electron spin resonance spectrometry and trolox equivalent antioxidant capacity (TEAC) assay. An adequate picture of phenolic compounds developed during maturation and ripening was determined using HPLC-DAD. Anthocyanins of all varieties increased during successive harvest stages; meanwhile flavonols and hydroxycinnamic acids decreased from unripe green to ripe blue stage of berry ripening. Blueberry antioxidant activity, as well as total phenolic content tended to decrease during ripening.
This IUPAC nomenclature document has been prepared to help establish a uniform and meaningful approach to terminology, notation, and formulation for performance characteristics of the chemical measurement process (CMP). Following definition of the CMP and its performance characteristics, the document addresses fundamental quantities related to the observed response and calibration, and the complement to the calibration function: the evaluation function. Performance characteristics related to precision and accuracy comprise the heart of the document. These include measures for the means or “expected values” of the relevant chemical quantities, as well as dispersion measures such as variance and standard error. Attention is given also to important issues involving: assumptions, internal and external quality control, estimation, error propagation and uncertainty components, and bounds for systematic error. Special treatment is given to terminology and concepts underlying detection and quantification capabilities in chemical metrology, and the significance of the blank. The document concludes with a note on the important distinction between the sampled population and the target population, especially in relation to the interlaboratory environment.
Strawberries are a good source of micronutrients, especially antioxidant phenolics. More information is needed to better exploit the health-promoting effect of such fruits. Several studies focused on the effects of genotype, cultural practices, and seasonal variation on the antioxidant potential of strawberries, but often yielding contradictory results and/or focusing on only 1 source of variability. In the present study, we showed that total phenolic compounds, ascorbic acid, and antioxidant capacity strongly differed between genotypes of strawberry. The precise results revealed the importance of genetic background for the antioxidant capacity and for the content of total phenolics (with up to 3.3-fold variations). Other parameters may also influence the antioxidant capacity in strawberry such as harvest time, culture conditions, and environmental factors. Moreover, in this study, the harvesting time (at the same ripening stage) appeared to be very important, more important than genotype. Variations of the antioxidant capacity of up to 4.1-folds were observed following the harvesting time of “Elsanta” cultivar.
Practical Application: This article compares the antioxidant capacity and the content in ascorbic acid and phenolic compounds of strawberries of different varieties and of fruits harvested from April to December at the same ripening stage. The importance of strawberry antioxidant capacity resides in its benefits for human health.
We have developed an analytical method using UHPLC-UV/ESI-TOF MS for the comprehensive profiling of the metabolites found in the methanolic extracts of 13 different varieties of avocado at two different ripening degrees. Both chromatographic and detection parameters were optimized in order to maximize the number of compounds detected and the sensitivity. After achieving the optimum conditions, we performed a complete analytical validation of the method with respect to its linearity, sensitivity, precision, accuracy and possible matrix effects. The LODs ranged from 1.64 to 730.54 ppb (in negative polarity) for benzoic acid and chrysin, respectively, whilst they were found within the range from 0.51 to 310.23 ppb in positive polarity. The RSDs for repeatability test did not exceed 7.01% and the accuracy ranged from 97.2% to 102.0%. Our method was then applied to the analysis of real avocado samples and advanced data processing and multivariate statistical analysis (PCA, PLS-DA) were carried out to discriminate/classify the examined avocado varieties. About 200 compounds belonging to various structural classes were tentatively identified; we are certain about the identity of around 60 compounds, 20 of which have been quantified in terms of their own commercially available standard.
Gas chromatography-atmospheric-pressure chemical ionization-time-of-flight mass spectrometry (GC-APCI-TOFMS) was compared to GC × GC-electron ionization (EI)-TOFMS, GC-EI-TOFMS, GC-chemical ionization (CI)-quadrupole mass spectrometry (qMS), and GC-EI-qMS in terms of reproducibility, dynamic range, limit of detection, and quantification using a mix of 43 metabolites and 12 stable isotope-labeled standards. Lower limits of quantification for GC-APCI-TOFMS ranged between 0.06 and 7.81 μM, and relative standard deviations for calibration replicates were between 0.4% and 8.7%. For all compounds and techniques, except in four cases, R(2) values were above 0.99. Regarding limits of quantification, GC-APCI-TOFMS was inferior to only GC × GC-EI-TOFMS, but outperformed all other techniques tested. GC-APCI-TOFMS was further applied to the metabolic fingerprinting of two Escherichia coli strains. Of 45 features that differed significantly (false discovery rate < 0.05) between the strains, 25 metabolites were identified through highly accurate and reproducible (Δm ± SD below 5 mDa over m/z 190-722) mass measurements. Starting from the quasimolecular ion, six additional metabolites were identified that had not been found in a previous study using GC × GC-EI-TOFMS and an EI mass spectral library for identification purposes. Silylation adducts formed in the APCI source assisted the identification of unknown compounds, as their formation is structure-dependent and is not observed for compounds lacking a carboxylic group.
The medicinal plants Hunteria umbellata (HUL), Cola lepidota (CCL), Persea americana leaf (PAL), Root bark of Persea americana (RPA) and Plukenetia conophora (PCL) are used in Nigerian traditional medicine for the treatment of cancer and cancer related diseases.
To scientifically evaluate the cell proliferative and apoptotic effects of the plants extracts using breast and osteocarcinoma cell lines, and also to identify the possible components via LC-MS to have a kind of chemical fingerprint.
The antiproliferative and apoptotic effects of methanolic extracts (10 μg/ml) of the five medicinal plants were subjected to in vitro evaluation using four cancer cell lines (breast-MCF-7 and BT-20; Osteocarcinoma-MG-63 and Saos-2) measured by flow cytometry. Non-tumorigenic controls MCF-12A and primary isolated osteoblasts (POB) were chosen to eliminate negative influence on healthy tissue.
Of the five extracts RPA demonstrated a significant (P<0.05) anti-proliferative activity against estrogen receptor positive breast cancer cell lines (MCF-7). The proliferative phase was decreased by 18%, whereas, a significant increase in cell proliferation (about 27%) was observed for RPA at a concentration of 10 μg/ml. PCL, CCL, HUL and PAL did not show marked inhibition of the proliferation of cell line MCF-7.
These results give suggestive evidence that the plant extracts exhibit some correlation between the claimed ethnomedicinal uses and the cell proliferative activity. RPA extract includes chemical compounds with estrogen-like activity and validates its potential use as anticancer agent, particularly against breast carcinoma; provided important information potentially helpful in drug designing and discovery. Further studies will involve the isolation of anti tumour compounds in RPA by LC-MS and detailed mechanism of anticancer activities.
Over the past decade, multimode ion sources operating at atmospheric pressure (i.e., more than one ionization method is operative in the ion source enclosure) have received considerable interest. Simultaneous operation of different ionization methods targeting different compound classes within one analysis run has several advantages, including enhanced sample throughput and thus significant laboratory cost reductions. Potential drawbacks are enhanced ion suppression and other undesirable effects of the simultaneous operation of ionization methods. In this contribution we present an alternative approach-the development and characterization of a widely applicable, multipurpose ion source operating at atmospheric pressure. The optimized source geometry allows rapid changing from LC-API methods (ESI, APCI, APLI) to GC-API methods (APCI, APLI, DA-APLI) along with the appropriate coupling of chromatographic equipment required. In addition, true multimode operation of the source is demonstrated for LC-ESI/APLI and LC-APCI/APLI.
A powerful HPLC-DAD-ESI-TOF MS method was established for the efficient identification of the chemical constituents in the methanolic extracts of avocado (Persea americana). Separation and detection conditions were optimized by using a standard mix containing 39 compounds belonging to phenolic acids and different categories of flavonoids, analytes that could be potentially present in the avocado extracts. Optimum LC separation was achieved on a Zorbax Eclipse Plus C18 analytical column (4.6×150 mm, 1.8 μm particle size) by gradient elution with water+acetic acid (0.5%) and acetonitrile as mobile phases, at a flow rate of 1.6 mL/min. The detection was carried out by ultraviolet-visible absorption and ESI-TOF MS. The developed method was applied to the study of 3 different varieties of avocado, and 17 compounds were unequivocally identified with standards. Moreover, around 25 analytes were tentatively identified by taking into account the accuracy and isotopic information provided by TOF MS.
A new analytical approach based on gas chromatography coupled to atmospheric pressure chemical ionization-time of flight mass spectrometry was evaluated for its applicability for the analysis of phenolic compounds from extra-virgin olive oil. Both chromatographic and MS parameters were optimized in order to improve the sensitivity and to maximize the number of phenolic compounds detected. We performed a complete analytical validation of the method with respect to its linearity, sensitivity, precision, accuracy and possible matrix effects. The LODs ranged from 0.13 to 1.05ppm for the different tested compounds depending on their properties. The RSDs for repeatability test did not exceed 6.07% and the accuracy ranged from 95.4% to 101.5%. To demonstrate the feasibility of our method for analysis of real samples, we analyzed the extracts of three different commercial extra-virgin olive oils. We have identified unequivocally a number of phenolic compounds and obtained quantitative information for 21 of them. In general, our results show that GC-APCI-TOF MS is a flexible platform which can be considered as an interesting tool for screening, structural assignment and quantitative determination of phenolic compounds from virgin olive oil.
Accurate mass measurement (used to determine elemental formulae) is an essential tool for impurity identification in pharmaceutical development for process understanding. Accurate mass liquid chromatography/mass spectrometry (LC/MS) is used widely for these types of analyses; however, there are still many occasions when gas chromatography (GC)/MS is the appropriate technique. Therefore, the provision of robust technology to provide accurate mass GC/MS (and GC/MS/MS) for this type of activity is essential. In this report we describe the optimisation and application of a newly available atmospheric pressure chemical ionisation (APCI) interface to couple GC to time‐of‐flight (TOF) MS.
To fully test the potential of the new interface the APCI source conditions were optimised, using a number of standard compounds, with a variety of structures, as used in synthesis at AstraZeneca. These compounds were subsequently analysed by GC/APCI‐TOF MS. This study was carried out to evaluate the range of compounds that are amenable to analysis using this technique. The range of compounds that can be detected and characterised using the technique was found to be extremely broad and include apolar hydrocarbons such as toluene. Both protonated molecules ([M + H] ⁺ ) and radical cations (M +. ) were observed in the mass spectra produced by APCI, along with additional ion signals such as [M + H + O] ⁺ .
The technique has been successfully applied to the identification of impurities in reaction mixtures from organic synthesis in process development. A typical mass accuracy of 1–2 m m/z units ( m/z 80–500) was achieved allowing the reaction impurities to be identified based on their elemental formulae. These results clearly demonstrate the potential of the technique as a tool for problem solving and process understanding in pharmaceutical development. The reaction mixtures were also analysed by GC/electron ionisation (EI)‐MS and GC/chemical ionisation (CI)‐MS to understand the capability of GC/APCI‐MS relative to these two firmly established techniques. Copyright © 2010 John Wiley & Sons, Ltd.
Gas Chromatography (GC)-Mass Spectrometry (MS) with Atmospheric Pressure (AP) interface was introduced more than 30 years ago but never became a mainstream technique, mainly because of technical difficulties and cost of instrumentation. A recently introduced multipurpose AP source created the opportunity to reconsider the importance of AP ionization for GC. Here, we present an analytical evaluation of GC/APCI-MS showing the benefits of soft atmospheric pressure chemical ionization for GC in combination with a Time of Flight (TOF) mass analyzer. During this study, the complete analytical procedure was optimized and evaluated with respect to characteristic analytical parameters, such as repeatability, reproducibility, linearity, and detection limits. Limits of detection (LOD) were found within the range from 11.8 to 72.5 nM depending on the type of compound. The intraday and interday repeatability tests demonstrate relative standard deviations (RSDs) of peak areas between 0.7%-2.1% and 3.8%-6.4% correspondingly. Finally, we applied the developed method to the analysis of human cerebrospinal fluid (CSF) samples to check the potential of this new analytical combination for metabolic profiling.
The California Hass avocado ( Persea americana ) is an example of a domesticated berry fruit that matures on the tree during its growing season but ripens only after being harvested. Avocados are typically harvested multiple times during the growing season in California. Previous research has demonstrated potential health benefits of avocados and extracts of avocado against inflammation and cancer cell growth, but seasonal variations in the phytochemical profile of the fruits being studied may affect the results obtained in future research. Therefore, in the present study, avocados were harvested in January, April, July, and September, 2008, from four different growing locations in California (San Luis Obispo, Ventura, Riverside, and San Diego) and analyzed for total fat content, fatty acid profile, carotenoids, and vitamin E. A significant increase in total carotenoid and fat content of avocados from all regions was noted as the season progressed from January to September. Four carotenoids not previously described in the avocado were quantified. The total content of carotenoids was highly correlated with the total fat content (r = 0.99, p < 0.001) demonstrating a remarkable degree of constancy of carotenoid intake per gram of fat content in the California Hass avocado. Future clinical research on the health benefits of the avocado should specify the time of harvest, degree of ripening, growing area, and the total phytochemical profile of the fruit or extract being studied. These steps will enable researchers to account for potential nutrient-nutrient interactions that might affect the research outcomes.
The ripeness degree of climacteric fruits, such as avocado ( Persea americana Mill.), can be correlated with rheological properties. However, there remains little information on not only the postharvest changes in texture of avocado fruit from different origins but also the spatial variation within fruit. In addition, the relationship between changes in texture and composition of fatty acids and major nonstructural carbohydrates (NSCs) of fruit tissue during ripening is unknown. The texture of different horizontally cut slices from individual fruits within a consignment was measured during ripening using a previously unreported technique. The composition of fatty acids and NSCs in fruit mesocarp tissue was determined. The composition of fatty acids and oil and dry matter contents varied significantly according to origin. Significant changes in texture, mannoheptulose and perseitol contents, and linoleic acid percentage were found in avocado fruit flesh during ripening. Spatial variation within fruit was detected in both textural and biochemical characteristics.
In this review of the scientific literature on the relationship between vegetable and fruit consumption and risk of cancer, results from 206 human epidemiologic studies and 22 animal studies are summarized. The evidence for a protective effect of greater vegetable and fruit consumption is consistent for cancers of the stomach, esophagus, lung, oral cavity and pharynx, endometrium, pancreas, and colon. The types of vegetables or fruit that most often appear to be protective against cancer are raw vegetables, followed by allium vegetables, carrots, green vegetables, cruciferous vegetables, and tomatoes. Substances present in vegetables and fruit that may help protect against cancer, and their mechanisms, are also briefly reviewed; these include dithiolthiones, isothiocyanates, indole-3-carbinol, allium compounds, isoflavones, protease inhibitors, saponins, phytosterols, inositol hexaphosphate, vitamin C, D-limonene, lutein, folic acid, beta carotene, lycopene, selenium, vitamin E, flavonoids, and dietary fiber. Current US vegetable and fruit intake, which averages about 3.4 servings per day, is discussed, as are possible noncancer-related effects of increased vegetable and fruit consumption, including benefits against cardiovascular disease, diabetes, stroke, obesity, diverticulosis, and cataracts. Suggestions for dietitians to use in counseling persons toward increasing vegetable and fruit intake are presented.
An atmospheric pressure chemical ionization (APCI) microchip is presented for combining a gas chromatograph (GC) to a mass spectrometer (MS). The chip includes capillary insertion channel, stopper, vaporizer channel, nozzle and nebulizer gas inlet fabricated on the silicon wafer, and a platinum heater sputtered on a glass wafer. These two wafers are joined by anodic bonding creating a two-dimensional version of an APCI microchip. The sample from GC is directed via heated transfer line capillary to the vaporizer channel of the APCI chip. The etched nozzle forms narrow sample plume, which is ionized by an external corona discharge needle, and the ions are analyzed by a mass spectrometer. The GC-microchip APCI-MS combination provides an efficient method for qualitative and quantitative analysis. The spectra produced by microchip APCI show intensive protonated molecule and some fragmentation products as in classical chemical ionization for structure elucidation. In quantitative analysis the GC-microchip APCI-MS showed good linearity (r(2) = 0.9989) and repeatability (relative standard deviation 4.4%). The limits of detection with signal-to-noise ratio of three were between 0.5 and 2 micromol/L with MS mode using selected ion monitoring and 0.05 micromol/L with MS/MS using multiple reaction monitoring.
Pigments are important contributors to the appearance and healthful properties of both avocado fruits and the oils extracted from these fruits. This study determined carotenoid and chlorophyll pigment concentrations in the skin and three sections of the flesh (outer dark green, middle pale green, and inner yellow flesh-nearest the seed) and anthocyanin concentrations in the skin of Hass avocado during ripening at 20 degrees C. Pigments were extracted from frozen tissue with acetone and measured using high-performance liquid chromatography. Pigments were also measured in the oil extracted from freeze-dried tissue sections by an accelerated solvent extraction system using hexane. Carotenoids and chlorophylls identified in the skin, flesh, and oil were lutein, alpha-carotene, beta-carotene, neoxanthin, violaxanthin, zeaxanthin, antheraxanthin, chlorophylls a and b, and pheophytins a and b with the highest concentrations of all pigments in the skin. Chlorophyllides a and b were identified in the skin and flesh tissues only. As the fruit ripened and softened, the skin changed from green to purple/black, corresponding to changes in skin hue angle, and a concomitant increase in cyanidin 3-O-glucoside and the loss of chlorophyllide a. In flesh tissue, chroma and lightness values decreased with ripening, with no changes in hue angle. The levels of carotenoids and chlorophylls did not change significantly during ripening. As fruit ripened, the total chlorophyll level in the oil from the flesh sections remained constant but declined in the oil extracted from the skin.
Detectors in modern gas chromatography Modern practice of gas chromatography (pp. 277–338) Determination of changes in the metabolic profile of avocado fruits (Persea americana) by two CE-MS approaches
- L A Colón
- L J Baird
- P K Gutiérrez
- E Hurtado-Fernández
- M Gómez-Romero
- J I Hormaza
- A Carrasco-Pancorbo
- A Gutiérrez
Colón, L. A., & Baird, L. J. (2004). Detectors in modern gas chromatography. In R. L. Grob, & E. F. Barry (Eds.), Modern practice of gas chromatography (pp. 277–338). Hoboken, New Jersey, USA: John Wiley and Sons. Contreras-Gutiérrez, P. K., Hurtado-Fernández, E., Gómez-Romero, M., Hormaza, J. I., Carrasco-Pancorbo, A., & Fernández-Gutiérrez, A. (2013). Determination of changes in the metabolic profile of avocado fruits (Persea americana) by two CE-MS approaches (targeted and non-targeted). Electrophoresis, 34, 2928–2942.