No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Bioactive properties of the aromatic molecules of spearmint (Mentha spicata L.) essential oil: a review
Abstract
Spearmint belongs to the genus Mentha in the family Labiatae (Lamiaceae), which is cultivated worldwide for its remarkable aroma and commercial value. The aromatic molecules of spearmint essential oil, including carvone, carveol, dihydrocarvone, dihydrocarveol and dihydrocarvyl acetate, have been widely used in the flavors and fragrances industry. Besides their traditional use, these aromatic molecules have attracted great interest in other application fields (e.g., medicine, agriculture, food, and beverages) especially due to their antimicrobial, antioxidant, insecticidal, antitumor, anti-inflammatory and antidiabetic activities. This review presents the sources, properties, synthesis and application of spearmint aromatic molecules. Furthermore, this review focuses on the biological properties so far described for these compounds, their therapeutic effect on some diseases, and future directions of research. This review will, therefore, contribute to the rational and economic exploration of spearmint aromatic molecules as natural and safe alternative therapeutics.
... The operating conditions for extracting the mint essence studied are summarized in the table below: The water content of the fresh plant is obtained by determining the moisture content using the Dean-Stark apparatus [7]: The relative density (dtt) of essential oil at a given temperature is the ratio between the mass of a given volume of the sample and the mass of the same volume of water at the same temperature dtt = Mass of a given volume of this species at a given T°/ Mass of the same volume of water at this T° [8]: ...
... Calculate the respective masses of water and essential oil (average). The relative density dt t is determined [8]. In practice, an aqueous dilution of the saponification medium is extracted with ethyl dioxide; after washing and removal of the solvent, the residue is weighed. ...
... Operating conditions for determining the various chemical indices[8,9,10] The plate is placed in the tank and development takes approximately 1 hour at 20°C. The plate is then removed from the tank to dry. ...
The species chosen for this study is sweet mint, Mentha spicata L, harvested in the wilaya of El Bayadh in Algeria. The aim of this work is to highlight the plant's identification criteria, its yield in essential oil, the various physico-chemical parameters and the composition of the essential oil using different techniques (determination of several chemical indices and establishment of the list of constituents of the essential oil using chromatographic methods). The botanical study showed the presence of two types of "Lamiaceae" type secretory hairs. These secretory hairs are the histological support for the production and storage of essential oils. A study of the kinetics of the extraction yield shows that distillation is rapid from 0 to 120 minutes, when the yield reaches an optimum (1.08%). The organoleptic characteristics and physico-chemical indices obtained are in line with the standards given in the bibliography. Thin layer chromatography revealed the presence of several constituents through the appearance of several spots of different colour and Rf, three of which were identified by comparison with controls, namely menthol, cineol and carvone.
... Concerning the terpenic profile, it should be highlighted that the treatment significantly affected only 8 out of 55 compounds. All the terpenes significantly accumulated in response to the mild-cyclic-drought stress (trans-carveyl acetate, carvone, p-menth-8-en-2-ol, bornyl acetate, 3-octanol acetate, bisabolene, and valencene) were commonly found as main components in spearmint essential oils (Balla et al., 2017;Salim et al., 2015;Salim, 2016;Zhang et al., 2022). In particular, the monoterpene carvone, which significantly accumulates at both T1 and T2, is the most abundant compound of spearmint essential oils, representing almost 70% of the blend (Balla et al., 2017;Salim et al., 2015;Salim, 2016;Zhang et al., 2022). ...
... All the terpenes significantly accumulated in response to the mild-cyclic-drought stress (trans-carveyl acetate, carvone, p-menth-8-en-2-ol, bornyl acetate, 3-octanol acetate, bisabolene, and valencene) were commonly found as main components in spearmint essential oils (Balla et al., 2017;Salim et al., 2015;Salim, 2016;Zhang et al., 2022). In particular, the monoterpene carvone, which significantly accumulates at both T1 and T2, is the most abundant compound of spearmint essential oils, representing almost 70% of the blend (Balla et al., 2017;Salim et al., 2015;Salim, 2016;Zhang et al., 2022). This result has certain importance since carvone is an industrially important compound, relevant in the medical field and used as a fragrance and flavour, antimicrobial agent, a building block for the synthesis of other compounds and potato sprouting inhibitor (Bouyahya et al., 2021;Committee, 2014;de Carvalho and da Fonseca, 2006). ...
Studying the impact of mild drought stress on plant productivity and product quality is essential in the context of climate change and dwindling water resources. Moreover, understanding how mild drought stress affects plants is crucial for sustainable agriculture, since it can potentially lead to the development of more efficient irrigation techniques, which, in turn, could enhance the resilience of agricultural systems, improve crop quality and reduce environmental impacts. In this contest, the study reports on the physiological and metabolic responses of spearmint (Mentha spicata L.) plants to cyclic-mild-drought stress. The research aimed to understand how plants adapt to water stress conditions and whether the nutraceutical and sensory characteristics of the plant can be enhanced by managing the water supply. Cyclic-mild-drought stress affected various physiological parameters of the plants [i.e. stomatal conductance, net photosynthesis, leaf temperature and leaf osmolality] but did not impact plant biomass and the photosynthetic machinery. Changes in leaf cation and anion concentration were not related to the observed changes in leaf osmolality, suggesting that the accumulation of organic compounds such as amino acids, sugars, organic acids, and phenolic acids mainly drove the osmotic adjustment. Finally, the comparison between the leaves' volatile profile of stressed and unstressed plants revealed that the cyclic-mild-drought stress significantly increased the concentration of carvone, the most representative and industrially important molecule produced by spearmint. Overall, the study's novelty is to provide insights into spearmint plants' physiological and metabolic responses to cyclic-mild-drought stress, highlighting potential strategies, after verification in open fields, to enhance plant productivity and quality by modulating water supply.
... Essential oils are a complex mixture of natural, volatile, and aromatic compounds synthesized by aromatic plants and are classified as monoterpenes and sesquiterpenes, according to the number of isoprene units, monoterpenes being the most abundant in essential oils. These volatiles have attracted lot of scientific interests because they exhibit a wide spectrum of bioactivities, such as antibacterial, antifungal, antiviral, antioxidant, and insecticidal activities (Chen et al., 2021; Zhang et al., 2022;Tariq et al., 2019) [7,28,25] . Rosemary (Rosmarinus officinalis L.), which belongs to mint family, is a common dense, evergreen, aromatic shrub grown in many parts of the world. ...
... Essential oils are a complex mixture of natural, volatile, and aromatic compounds synthesized by aromatic plants and are classified as monoterpenes and sesquiterpenes, according to the number of isoprene units, monoterpenes being the most abundant in essential oils. These volatiles have attracted lot of scientific interests because they exhibit a wide spectrum of bioactivities, such as antibacterial, antifungal, antiviral, antioxidant, and insecticidal activities (Chen et al., 2021; Zhang et al., 2022;Tariq et al., 2019) [7,28,25] . Rosemary (Rosmarinus officinalis L.), which belongs to mint family, is a common dense, evergreen, aromatic shrub grown in many parts of the world. ...
... Some authors have reported spearmint compounds with multiple applications in the generation of functional foods and personal care products [9], primarily phenolic acids such as protocatechuic acid, hydroxybenzoic acid, 4-hydroxy cinnamic acid, caffeic acid, syringic acid and ferulic acids, gallic acid, vanillic acids, p-coumaric acid, and rosmarinic acids [10]. For similar applications, flavonoids such as thymonin, naringenin, rutin, quercetin, esculetin, nodifloretin, luteolin, and scopoletin have also been reported [10]. ...
... As these conditions are variable in different origins, that could shape the metabolic profile of each commercial material. Furthermore, a specific metabolic profile varies significantly depending on the extract preparation, particularly when it comes to industrial processing for different industries [9]. ...
Spearmint (Mentha spicata L.) has been widely studied for its diversity of compounds for product generation. However, studies describing the chemical and biological characteristics of commercial spearmint materials from different origins are scarce. For this reason, this research aimed to bioprospecting spearmint from three origins: Colombia (Col), Mexico (Mex), and Egypt (Eg). We performed a biological activity analysis, such as FRAP, DPPH, and ABTS, inhibition potential of S. pyogenes, K. pneumoniae, E. coli, P. aeuroginosa, S. aureus, S aureus Methicillin-Resistant, and E. faecalis. Furthermore, we performed chemical assays, such as total polyphenol and rosmarinic acid, and untargeted metabolomics via HPLC-MS/MS. Finally, we developed a causality analysis to integrate biological activities with chemical analyses. We found significant differences between the samples for the total polyphenol and rosmarinic acid contents, FRAP, and inhibition analyses for Methicillin-Resistant S. aureus and E. faecalis. Also, clear metabolic differentiation was observed among the three commercial materials evaluated. These results allow us to propose data-driven uses for the three spearmint materials available in current markets.
... The essential oil components of M. spicata have been extensively reviewed [6,9,10]. The essential oil composition studies have shown a variety of the major compounds in ...
Wild growing Origanum majorana L. var. tenuifolium Weston was collected from three different locations (Om1: Avtepe, Om2: Alevkayası, Om3: Kozanköy) in North Cyprus. The essential oils were hydrodistilled and chemical composition analyses were simultaneously performed by GC-FID and GC-MS. The average yields of essential oils were 5.46-8.14%. Major compounds of flowering Om1 oil were cis-sabinene hydrate (45.0%) and terpinen-4-ol (11.1%) while those of Om3 (Kozanköy) oil were cis-sabinene hydrate (33.3%), terpinen-4-ol (12.3%) and α-terpineol (11.5%). In the postf lowering stage, the major compounds for Om1 and Om3, respectively, were cis-sabinene hydrate (16.7% and 18.8%), terpinen-4-ol (18.1% and 14.5%) and α-terpineol (23.9% and 20.0%). However, the main compound of the essential oils of the flowering and post-flowering oil of Om2 was α-terpineol (76.9% and 51.6%). Statistical Principal Component (PCA) and Hierarchical Cluster Analyses (HCA) tools demonstrated the composition variations of the essential oils at different times and locations. Om1 and Om3 (HCA similarity level: 98.98%) were similar while Om2 (HCA similarity level: 46.32%) was discordant.
... Spearmint has anti-inflammatory, analgesic, antioxidant and antimicrobial activities, among others (Miraj & Kiani 2016). Additionally, it is extensively used in the food industry as a natural flavoring agent (Miraj & Kiani 2016, Mahendran et al. 2021, Zhang et al. 2022. ...
Drought stress is a critical factor affecting plant growth and development. Understanding the effects of drought on the physiology of medicinal plants can contribute to the implementation of better water management techniques and promote a sustainable production. This study aimed to evaluate the influence of water stress on the growth and development of Mentha spicata L. plants. A completely randomized design was used, with two water conditions: irrigated and non-irrigated. The water deficit negatively affected the dry weight of roots and shoots, with a decrease in the transpiration rate and chlorophyll content, potentially impairing the photosynthetic activity. However, the essential oil production was not affected in plants subjected to water deficiency, indicating that the essential oil production may be more resilient to drought stress in this species.
KEYWORDS:
Spearmint; medicinal plant; photosynthesis
... EOs from Mentha spicata L. are widely used in the food, cosmetics, perfume, beverage, pharmaceutical, and tobacco industries [3].Ćavar Zeljković et al. [4] reported that mint is rich in phenolic compounds, which exhibit antioxidant properties that are useful in the food industry. The EOs from Mentha spicata L. have been incorporated in several products, such as toothpastes, mouthwashes, perfumes, and beverages [5]. ...
In this study, we assessed the effects of different harvest times (9 a.m., 1 p.m., and 5 p.m.) and hydrodistillation times (60, 90, and 120 min) on the yield, chemical composition, and antioxidant activity of the spearmint (Mentha spicata L.) essential oil (EO) sourced from the Amazon region. EO yield was ≥1.55% and was not significantly influenced (p ≥ 0.05) by the different harvest times and hydrodistillation times. Thirty-one different organic compounds were identified, of which menthol (91.56–95.68%), menthone (0.6–2.72%), and isomenthone (0.55–1.46%) were the major constituents. The highest menthol content in the EO was obtained from samples collected at 9 a.m., with a hydrodistillation time of 60–90 min, compared to other harvest and hydrodistillation times. This suggests that exposure to sun and light, which is greater at harvest times of 1 p.m. and 5 p.m., decreased the menthol content and altered the chemical composition of Mentha EO. Furthermore, the sample harvested at 9 a.m. and hydrodistilled for 60 min showed the highest antioxidant activity (61.67 equivalent mg of Trolox per g of EO), indicating that antioxidant activity is strongly affected by light exposure and the contact duration of the sample with boiling water during hydrodistillation.
... MHB is native to China and widely distributed in the temperate regions of the Northern Hemisphere. China has the world's largest cultivation area and yield of MHB [5,6]. In addition, MHB also has the characteristics of a fast growth rate and a high yield. ...
Simple Summary
Mentha haplocalyx Briq (MHB) is a medicinal and edible herbal plant that has the effects of clearing heat, detoxifying, and aiding digestion as a traditional Chinese medicine. However, there is limited research on MHB as a feed ingredient for meat sheep. This study shows that adding MHB to feed can improve the growth performance of fattening sheep. We have revealed the mechanism by which MHB affects the growth and metabolism of meat sheep through aspects such as rumen and fecal microbial sequencing, rumen metabolomics, serum metabolomics, urine metabolomics, and rumen epithelial cell transcriptome sequencing. Our research results will provide a theoretical basis for the application of MHB in the production of meat sheep.
Abstract
Mentha haplocalyx Briq (MHB) and its components have been proven to improve the growth performance of livestock and poultry. The aim of this experiment was to investigate the effects of MHB addition on growth performance, rumen and fecal microbiota, rumen fluid, serum and urine metabolism, and transcriptomics of rumen epithelial cells in meat sheep. Twelve Hu sheep were selected for the experiment and fed with basic diet (CON) and a basal diet supplemented with 80 g/kg DM of Mentha haplocalyx Briq (MHB). The experimental period was 10 weeks with the first 2 weeks as the pre-trial period. The results showed that compared with the CON group, the average daily weight gain of meat sheep in the MHB group increased by 20.1%; the total volatile fatty acid (VFA) concentration significantly increased (p < 0.05); The thickness of the cecal mucosal layer was significantly reduced (p < 0.01), while the thickness of the colonic mucosal layer was significantly increased (p < 0.05), the length of ileal villi significantly increased (p < 0.01), the thickness of colonic mucosal layer and rectal mucosal muscle layer significantly increased (p < 0.05), and the thickness of cecal mucosal layer significantly decreased (p < 0.05); The serum antioxidant capacity has increased. At the genus level, the addition of MHB changed the composition of rumen and fecal microbiota, increased the relative abundance of Paraprevotella, Alloprevotella, Marinilabilia, Saccharibacteria_genera_incertae_sedis, Subdivision5_genera_incertae_sedis and Ornatilinea in rumen microbiota, and decreased the relative abundance of Blautia (p < 0.05). The relative abundance of Prevotella, Clostridium XlVb and Parasutterella increased in fecal microbiota, while the relative abundance of Blautia and Coprococcus decreased (p < 0.05). There were significant differences in the concentrations of 105, 163, and 54 metabolites in the rumen, serum, and urine between the MHB group and the CON group (p < 0.05). The main metabolic pathways of the differences were pyrimidine metabolism, taurine and taurine metabolism, glyceride metabolism, and pentose phosphate pathway (p < 0.05), which had a significant impact on protein synthesis and energy metabolism. The transcriptome sequencing results showed that differentially expressed genes were mainly enriched in immune regulation, energy metabolism, and protein modification. Therefore, adding MHB improved the growth performance of lambs by altering rumen and intestinal microbiota, rumen, serum and urine metabolomics, and transcriptome.
... Carvone, limonene, and menthol act as analgesics with short-term effects. The phenolic and volatile compounds therein were found to have strong antimicrobial, antiviral, antioxidant, and antitumor effects [122]. Unfortunately, the findings from human clinical trials are limited, despite the fact that a positive effect on gastrointestinal tissue and the nervous system has been noted. ...
Citation: Iordache, A.M.; Nechita, C.; Podea, P.; S , uvar, N.S.; Mesaros. , C.; Voica, C.; Bleiziffer, R.; Culea, M. Comparative Amino Acid Profile and Antioxidant Activity in Sixteen Plant Extracts from Transylvania, Romania. Plants 2023, 12, 2183. https:// Abstract: In addition to the naturopathic medicines based on the antiseptic, anti-inflammatory, anticancer, or antioxidant properties of plant extracts that have been capitalized upon through the pharmaceutical industry, the increasing interest of the food industry in this area requires potent new materials capable of supporting this market. This study aimed to evaluate the in vitro amino acid contents and antioxidant activities of ethanolic extracts from sixteen plants. Our results show high accumulated amino acid contents, mainly of proline, glutamic, and aspartic acid. The most consistent values of essential amino acids were isolated from T. officinale, U. dioica, C. majus, A. annua, and M. spicata. The results of the 2,2-diphenyl-1-pycrylhydrazyl (DPPH) radical scavenging assay indicate that R. officinalis was the most potent antioxidant, followed by four other extracts (in decreasing order): T. serpyllum, C. monogyna, S. officinalis, and M. koenigii. The network and principal component analyses found four natural groupings between samples based on DPPH free radical scavenging activity content. Each plant extracts' antioxidant action was discussed based on similar results found in the literature, and a lower capacity was observed for most species. An overall ranking of the analyzed plant species can be accomplished due to the range of experimental methods. The literature review revealed that these natural antioxidants represent the best side-effect-free alternatives to synthetic additives, especially in the food processing industry.
... These properties are primarily attributed to essential oils present in spearmint that contain various aromatic compounds like carvone, limonene, carveol, dihydrocarvone, dihydrocarveol, and dihydrocarvyl acetate, which also contributes to the characteristic aroma of the plant (Mahendran et al., 2021). Besides their ethnopharmacological uses, these essential oils have various applications in the agricultural, medicinal, sanitary, food, and beverage industries (Mahendran et al., 2021;Zhang et al., 2022). Considering these advantages, the demand for these oils is on the rise and will continue to rise in the coming future. ...
Efficacy of oryzalin to generate novel genotypes of Mentha spicata L. with superior morphology and enhanced levels of essential oil via in vitro polyploidization was assessed. Micropropagated nodal segments were treated with oryzalin at 20, 40, and 60 μM for 24 and 48 h. The survival rate of the nodal segments dropped significantly with the increasing concentration and duration of oryzalin. Further, the ploidy level of the survived plants was confirmed using flowcytometry and chromosome counting. A total of six polyploids (2 n = 6x = 72) and six mixoploid plants were obtained. The highest frequency of polyploids (8 %) was induced in treatment where 40 μM oryzalin was applied for 48 h. The obtained polyploids exhibited significantly larger, thick, dark green leaves with elongated stomata compared with the control genotype. The polyploid plants also displayed higher moisture content and vigorous lateral growth. The essential oil yield of hexaploid M. spicata exhibited a 48.85 % increase, rising from 1.74 % in control to 2.59 % (v/w) in genotype P3. The major components of essential oils were carvone and limonene, which also increased significantly compared with the control genotype. The nutrient profile of the studied genotypes was influenced vastly and showed significant variations. Overall, the employed methodology using oryzalin as an antimitotic agent for polyploid induction in M. spicata was found to be effective. Despite relatively low polyploid induction frequency, the obtained polyploid genotypes demonstrated various superior agronomical traits. The genotypes obtained could serve to aid the commercial demands.
... Moreover, our data of both physical parameters have been found to be in accordance with the study of the mentioned authors (Valková et al., 2022b). A strong antifungal potential of our SEO against the mycelial growth of all three Penicillium species could be explained by the presence of oxygenated monoterpenes, such as carvone that has emerged as a promising antifungal compound (Bouyahya et al., 2021) due to its disruptive impact on the cell membrane and fungal mitochondria (Zhang et al., 2022). Also, limonene (another major component of SEO) is able to inhibit the growth of C. albicans by generation of oxidative stress in the cell envelope and induction of oxidative DNA damage, leading to cell-cycle modulation and apoptosis (Sales et al., 2022). ...
Attention of the scientific community has still focused on application of essential oils (EOs) as natural antifungal agents in the food industry to prolong the shelf-life of food products. In this regard, the current study was designed to evaluate chemical composition, antioxidant capacity, and antifungal (in vitro, in situ) activities of spearmint (Mentha spicata var. crispa) essential oil (SEO) commercially obtained from Slovak company against selected Penicillium species. The EO was used in four concentrations (62.5, 125, 250, and 500 µL/L) chosen, and gas chromatography–mass spectrometry, DPPH, agar disc diffusion and vapor phase methods were employed for such analyses. Our results revealed carvone (57.5%) and α-limonene (17.6%) to be the principal constituents in the EO chemical composition. Although only a weak antioxidant capacity (20.40 ± 0.80% free radical-scavenging inhibition) was displayed by the SEO, the highest EO concentration (500 µL/L) was shown to be a moderate growth inhibitor of P. expansum (inhibition zone of 11.46 ± 0.63 mm) and P. crustosum (inhibition zones of 12.93 ± 0.46 mm). The growth of P. citrinum was only weakly inhibited by the SEO (≥ 250 µL/L). Most importantly, the ability of the SEO to inhibit the mycelial growth of three Penicillium spp. tested was pronounced (P < 0.05) for all applied concentrations. Accordingly, the results from the current study complement our previous ones dealing with the possibility of utilizing diverse EOs commercially achieved from the same company in the food sector.
... lycopersici or Verticillium ahlia, did not show disease symptoms 50 days after the transplantation of inoculated tomato at a net-greenhouse, whereas the outcome of this study strongly supports that of the AUDPC values (area under diseases progress curves): for both fungi inoculation, plants grown in soil incorporation with spearmint had up to 3.5 times lower AUDPC compared to the positive controls. Moreover, M. spicata EO at a 10% concentration showed a complete reduction of disease incidence of Botrytis cinerae, one of the most significant strawberry postharvest pathogen, indicating the possible exploitation of this EO as an antifungal means of the preservation of strawberries [48]. ...
The potential applications of the genus Mentha as natural pesticides and environmentally friendly postharvest treatments for agricultural products in sustainable agriculture are reviewed here. The non-commercialized Mentha species in Greece and the rest of the world are presented, and the possibility of their exploitation is discussed. Recent developments in successive methods of application—i.e., the formulation of Mentha extracts/oils in eco-friendly pesticides, fumigation, and the assessment of performance in field trials—are also reported. Several studies have shown that Mentha species in various forms (e.g., essential oil (EO), aqueous extract, fresh or dried plant material, compost, etc.), or in different cropping systems (e.g., crop rotation, intercropping system/cover crop, cultivation and incorporation as green manure) offer the potential to be used in agriculture, with the goal of managing plant pathogens (bacteria and fungi), animal pests (insects, acarines, and nematodes), weeds, and for the improvement of soil quality and productivity as well. Finally, several studies are presented concerning the enhancement of Mentha EOs effectiveness in agriculture, and to also overcome the limitations of their nature (being unstable when exposed to light and oxygen), by using a combination of EOs, or by developing novel formulations (microencapsulation). Taking into consideration all the abovementioned findings, it is evident that Mentha species could be used in sustainable agricultural systems for integrated pest management. This can be achieved utilizing them either directly as a crop, green manure, or compost, or indirectly by developing natural pesticides based on their EOs or extracts. Nonetheless, further field experiments must be conducted, to confirm the efficacy of various formulas on pests under crop conditions.
... There is growing evidence that OBPs specifically expressed in antennae are involved in long-distance chemical communication [71,72]; for example, the antenna-specific OBP, Bdorsobp2 in Bactrocera dorsalis Hendel, is implicated in the recognition of methyl eugenol, a potential species-specific attractant, based on RNAi, electrophysiological, and behavioral evidence [73], while BodoOBP1 and BodoOBP2, which are specifically expressed in male antennae of Bradysia odoriphaga Yang et Zhang, have been demonstrated to participate both in host localization and courtship behavior [74]. A similar situation was observed in our study of O. lotOBP6, where both fluorescent binding assay and choice assays demonstrated the strong interaction of this protein with p-Menth-8-en-2-one, which was mainly found in Mentba L. and extensively used as spice [75]. ...
To identify odors in complex environments accurately, insects have evolved multiple olfactory proteins. In our study, various olfactory proteins of Odontothrips loti Haliday, an oligophagous pest that primarily affects Medicago sativa (alfalfa), were explored. Specifically, 47 putative olfactory candidate genes were identified in the antennae transcriptome of O. loti, including seven odorant-binding proteins (OBPs), nine chemosensory proteins (CSPs), seven sensory neuron membrane proteins (SNMPs), eight odorant receptors (ORs), and sixteen ionotropic receptors (IRs). PCR analysis further confirmed that 43 out of 47 genes existed in O. loti adults, and O.lotOBP1, O.lotOBP4, and O.lotOBP6 were specifically expressed in the antennae with a male-biased expression pattern. In addition, both the fluorescence competitive binding assay and molecular docking showed that p-Menth-8-en-2-one, a component of the volatiles of the host, had strong binding ability to the O.lotOBP6 protein. Behavioral experiments showed that this component has a significant attraction to both female and male adults, indicating that O.lotOBP6 plays a role in host location. Furthermore, molecular docking reveals potential active sites in O.lotOBP6 that interact with most of the tested volatiles. Our results provide insights into the mechanism of O. loti odor-evoked behavior and the development of a highly specific and sustainable approach for thrip management.
... In the case of the essential oil of Siparuna muricata, it is worth noting its strong, persistent and distinctive aroma of lemon. Numerous examples of species with relatively low yields are recognized and exploited for their cosmetic, seasoning and medicinal qualities, such as Achillea millefolium L. [24], Aloysia citriodora Palau [25], Mentha spicata L. [26], Tagetes minuta L., and others. ...
Siparuna muricata is an aromatic native shrub or tree from Ecuador known as “limoncillo” or “limón de la sierra” due to its citrus odor. In this study, the chemical composition and biological activity of essential oil from the leaves and fruits of this species was determined. The essential oil was isolated by subjected to hydrodistillation. The chemical composition was determined by gas chromatography equipped with a flame ionization detector and gas chromatography coupled to mass spectrometry. The enantiomeric distribution was determined by gas chromatography using an enantioselective column. The antimicrobial activity against three Gram-positive bacteria, two Gram-negative bacteria and two fungi was determined by the broth microdilution method. The antioxidant activity was analyzed using the 2,2-diphenyl-1-picrylhydryl free radical and 2,2’-azinobis-3-ethylbenzothiazoline-6-sulfonic acid radical cation scavenging activity of essential oil. The acetylcholinesterase inhibitory effect of the essential oil was measured using a spectrophotometric method. The yield was 1.2 ± 0.1 mL/kg for leaves and 1.8 ± 0.2 mL/kg for fruits. A total of 51 compounds were identified in the leaves of the essential oil and 41 in the fruits. In both cases, the chemical compositions were dominated by the group of monoterpene hydrocarbons compounds. The main compound was α-pinene with 23.22 ± 1.03% in essential oil of the leaves and limonene with 24.92 ± 1.20% in the fruits. In both essential oils, five pairs of enantiomers with different enantiomeric excesses were identified. The essential oil of limoncillo leaves presented a strong activity against the fungus Aspergillus niger (ATTC 10231) and Gram-positive bacterium Enterococcus faecium (ATCC 27270) with a MIC of 250 μg/mL and 500 μg/mL, respectively. The essential oil from fruits and leaves of Siparuna muricata presented a moderate antioxidant activity with the ABTS method with a SC50 of 775.3 ± 1.3 µg/mL and 963.3 ± 1.6 µg/mL, respectively. Additionally, the leaves essential oil reported an IC50 value of 52.98 ± 1.04 µg/mL and the fruits essential oil an IC50 value of 98.84 ± 1.04 µg/mL, which can be considered a very strong anticholinesterase activity.
... As is known, essential oils are constituted by complex mixtures of low molecular weight natural compounds, including phenols, terpenes, ketones, alcohols, aldehydes, hydrocarbons, etc., [2]. Due to the existence of these natural compounds, essential oils have exhibited a variety of biological effects in animal and cellular models, such as anti-insect, anticancer, antioxidant, antimicrobial, and anti-inflammatory effects [3]. For example, the essential oil extracted from Rosmarinus officinalis could inhibit the inflammation symptoms of several animal models, including paw edema induced by carrageenin, ear edema induced by croton seed oil, and granuloma tissue induced by cotton pellet [4]. ...
In order to assess the sunflower oil (SFO) oxidative stability that was added by the essential oils extracted from Lonicera japonica flower buds (LJEO) during deep-frying at 180 °C for 30 h, we clarified the compound/compounds of LJEO that improved the oxidative stability of SFO. The results displayed that the addition of LJEO (0.06 g/kg) could significantly restrict the elevation or the reduction in the levels of total polar compounds (TPC), thiobarbituric acid (TBA), conjugated dienes and conjugated trienes, and the values for polymer, viscosity and the color of SFO during the whole period. Meanwhile, the reduction in the sensory attributes, including flavor, taste, crispness and overall acceptability of the fried product, youtiao, was obviously restricted as well. After the bioassay-guided fractionation of LJEO and repeated deep-frying at 180 °C for 30 h, one of its chemical constituents, eugenol, was demonstrated to be the very compound that did significantly inhibit the oxidative rancidity of the SFO. Therefore, eugenol may be employed as potential effective natural antioxidants to inhibit the oxidative rancidity of SFO during its deep-frying procedures.
Medicinal and aromatic plants (MAPs) are potential sources of natural polyphenols. Solid residues (SRs) from the essential oil (EO) industry are produced in significant volumes and may be used as natural sources of bioactive compounds. Therefore, this work was designed to examine the antioxidant and antibacterial characteristics of phenolic extracts obtained from SRs that have remained after EO distillation. SR extracts of Greek oregano, rosemary, spearmint, lemon balm, and Greek sage were assessed for their total phenolic content (TPC), antioxidant activity, and antimicrobial activity against Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, Staphylococcus aureus, Bacillus subtilis, Bacillus licheniformis, and Bacillus cereus in the concentration range of 500-3000 mg/L. The rosemary and Greek sage extracts exhibited the strongest antibacterial activities against all the Gram-positive species, while the spearmint and oregano extracts were less effective and only had an effect at the highest concentration used. The lemon balm extract did not show any inhibitory effect; however, it had the highest TPC, showing moderate antioxidant activity, along with spearmint. The oregano extract exhibited the strongest antioxidant activity, followed by Greek sage and rosemary. The experimental findings pointed to the potential use of extracts from post-distillation residues of MAPs as antimicrobials in the food industry, in addition to being rich sources of bioactive compounds.
The aims of this article were to optimize and assay the production of high value aroma compounds at a bench-scale by the bioconversion capacity of Aspergillus niger LBM055 strain using R-limonene as platform chemical. Temperature, pH and agitation effect on R-limonene bioconversion were evaluated. Optimal R-limonene bioconversion was met at 30.5 \(^{\circ }\hbox {C}\), 100 rpm and pH 6.2, meanwhile best yield of high molecular weights products was obtained at 28 \(^{\circ }\hbox {C}\), 100 rpm and pH 5.4. Conditions of best yield of high molecular weights were selected to apply them at a bench-scale bioreactor. \(\alpha \)-pinene, \(\beta \)-pinene, citral, linalool, carvone, carveol and myrcene were identified. Also, a mixture of carvone, carveol and limonene oxide at a high concentration of 3.1 g/L, was identified by GC-MS analysis. Optimization analysis demonstrated that with the same substrate and fungal strain, it was possible to obtain different bioaromas compounds only by changing the operating conditions. Applying the operating parameters in a bench-scale bioreactor, a composite biofragrance of a terpene mixture, recognized by their citric, woody, floral and minty aromatic notes, was obtained. This study contributed to identified operational condition for the R-limonene bioconversion scale-up for the extension in the citrus industry value chain.
Background
Medicinal plants and herbs constitute rich sources of flavoring, and aromatic compounds, namely phytochemicals, which have many positive impacts on human health, such as antioxidant, anticancer, antimicrobial, anti-inflammatory, cardioprotective, and neuroprotective properties. Such bioactive compounds may be considered lead compounds that can be introduced in the drug design process to obtain novel drug candidates with better bioavailability and therapeutic efficiency. The Islands of the North Aegean have rich biodiversity and many medicinal plants and herbs with multiple health benefits.
Objective
This study aims to summarize and scrutinize the antioxidant activity of medicinal plants and herbs of the North Aegean islands.
Methods
A thorough search of the existing literature was performed in the most accurate scientific databases, using a set of effective and relative keywords and including only clinical human studies written in English.
Results
Several clinical studies have highlighted the potential antioxidant activity of phytochemicals from plants such as St. John's wort, chamomile, rosemary, spearmint, mastiha, mountain tea, oregano, sage, and thyme, as measured in the blood and saliva of human individuals, after administration of extracts and solutions of these plants. Decreased levels of oxidized lipoproteins, increased activity of antioxidant enzymes, and an enhanced total antioxidant capacity were observed.
Conclusions
Current clinical trials remain still limited, and an enhanced series is needed with a better methodology design, larger sample size, longer intervention periods, using controlled groups and randomization to unravel the antioxidant activity of these North Aegean endemic plants in human individuals.
Spearmint (Mentha spicata L.) is grown for its essential oil (EO), which find use in food, beverage, fragrance and other industries. The current study explores the ability of near infrared hyperspectral imaging (HSI) (935 to 1720 nm) to predict, in a rapid, nondestructive manner, the essential oil content of dried spearmint (0.2 to 2.6% EO). Spectral values of spearmint samples varied considerably with spatial coordinates, and so the use of averaging the spectral values of a surface scan was warranted. Data preprocessing was done with Multiplicative Scatter Correction (MSC) or Standard Normal Variate (SNV). Selection of spectral input variables was done with Least Absolute Shrinkage and Selection Operator (LASSO), Principal Component Analysis (PCA) or Partial Least Squares (PLS). Regression was executed with linear regression (LASSO, PLS regression, PCA regression), Support Vector Machine (SVM) regression, and Multilayer Perceptron (MLP). The best prediction of EO concentration was achieved with the combination of MSC or SNV preprocessing, PLS dimension reduction, and MLP regression (1 hidden layer with 6 nodes), achieving a good prediction with a ratio of performance to deviation (RPD) of 2.84 ± 0.07, an R² of prediction of 0.863 ± 0.008, and a RMSE of prediction of 0.219 ± 0.005% EO. These results show that NIR-HSI is a viable method for rapid, nondestructive analysis of EO concentration. Future work should explore the use of NIR in the visible spectrum, the use of HSI for determining EO in other plant materials and the potential of HSI to determine individual compounds in these solid plant/food matrices.
This study aimed at evaluating changes of microalgae Spirulina during its fermentation with Lactiplantibacillus plantarum No. 122 strain, and further at incorporating Spirulina bio-converted for nutraceuticals rich in L-glutamic (L-Glu) and gamma-aminobutyric acids (GABA) into sucrose-free chewing candy (gummy) preparations. Fermented Spirulina had higher b* (yellowness) coordinates than untreated (non-fermented), and fermentation duration (24 and 48 h) had a statistically significant effect on colour coordinates. The highest contents of L-glutamic and gamma-aminobutyric acids (4062 and 228.6 mg/kg, respectively) were found in 24 and 48 h-fermented Spirulina, respectively. Fermentation increased the content of saturated fatty acids and omega-3 in Spirulina, while monounsaturated fatty acids and omega-6 were reduced. The addition of fermented Spirulina (FSp) significantly affected hardness, decreased lightness and yellowness, and increased the greenness of chewing candies. All chewing candy samples (with xylitol) prepared with 3 and 5 g of FSp and 0.2 µL of Citrus paradise essential oil received the highest scores for overall acceptability, and the highest intensity (0.052) of emotion “happy” was elicited by the sample group containing xylitol, agar, ascorbic acid, 3 g of FSp, and 0.1 µL of Mentha spicata essential oil. As an outcome of this research, one may conclude that fermented Spirulina has significant potential as an innovative ingredient in the production of healthier sucrose-free nutraceutical chewing candies.
Organic cultivation is an eco-friendly planting strategy. To explore the effects of organic cultivation on yield, grain quality, and volatile organic compounds of fragrant rice, the present study conducted a field experiment with organic cultivation and inorganic cultivation treatments over two subsequent growing seasons. The late season rice was sent for the determination of untargeted flavoromics using GC × GC-ToF-MS. Meanwhile, the GC × MS were used for the quantification of 2-acetyl-1-pyrroline. Our results showed that compared with inorganic cultivation, organic cultivation increased grain 2-AP and amylose contents by 21.19-26.10% and 4.51-7.69%, respectively. 5.89%-15.55% lower crude protein contents were recorded in organic cultivation. The results of untargeted flavoromics showed that organic cultivation caused the absence of 56 volatiles and the exclusive presence of 10 new volatiles compared with inorganic cultivation. In conclusion, organic cultivation produced fragrant rice with lower yield and higher 2-AP content as well as different flavor profiles.
This study aimed to develop a nutritious yogurt drink with the best hydrosol (HS) extracted from Eryngium caucasicum Trautv based on bioactive compounds and bio-functional properties. Four extraction methods, namely conventional hydrodistillation (CHD, 85 °C for 4 h), microwave-assisted (MAHD, 350 W for 10 min), ultrasound-assisted (UAHD, 24 kHz, 225 W for 30 min), and ultrasound microwave-assisted (UMAHD) hydrodistillation after the single-factor optimization, were employed to obtain HSs from E. caucasicum Trautv (solid/water of 1:10) with the highest yield and antioxidant activity. Results showed that the most dominant bioactive compounds in HSs extracted by CHD and UAHD, respectively, were pulegone and carvone, while cis-dihydrocarvone was the major constituent of HSs extracted by MAHD and UMAHD. The GC–MS analysis showed that the oxygenated monoterpenes were the most abundant components in E. caucasicum Trautv HS (32.34–79.49%). The extracted HS from UAHD compared to other techniques significantly had more yield (84.46%), DPPH˙ scavenging activity (83.04%), Fe3+ reducing power (0.473 at Å700 nm), and total phenolic (TPC, 10.34 mg GAE/g), flavonoid (TFC, 1008.21 mg CE/100 mL), carotenoid (TCaC, 511.21 mg/kg), and chlorophyll (TChC, 152.39 mg/kg) contents (p < 0.05). No significant difference in the yield (73.75–76.39%), DPPH˙ scavenging activity (72.98–74.23%), and TChC (86.84–93.22 mg/kg) was found between two bioactive extracts of MAHD and UMAHD. The extract obtained from CHD had the lowest quantitative and qualitative values (p < 0.01). The UAHD-HSs exhibited the strongest antimicrobial (i.e., Escherichia coli and Salmonella enterica subsp. Enterica) and antitumor (i.e., hepatoma (HepG2) and lung (A549) cancer cell lines) activities. The dairy product incorporated with UAHD-HS as a functional food showed the best panelists' sensory scores for consumers' preferences.
In this study, spearmint plants inoculated with arbuscular mycorrhizal (AM) fungi were sprayed with 0.66 and 1.05 mg ("low"and "high") of elemental Cu per pot from Cu(OH)2 nanowires, bulk Cu(OH)2 (Kocide 3000), or ionic CuSO4. After a 50-day growth period spearment plants were harvested for argonomical, biochemical, and elemental analysis. Accumulation of Cu was highest in the roots (149.40-427.03 mg kg-1). In general, Cu-based nanoparticles (NPs)/compounds were toxic, inhibiting plant growth and element accumulation. The root biomass and length were reduced by up to 8.38 g and 11.80 cm or 59.92 and 48.15%, respectively. A majority of alterations in element accumulation occurred in the leaves, with significant decreases in Mg (≤10.47 mg kg-1 or 22.59%), Mn (≤0.77 mg kg-1 or 39.77%), and Zn (≤0.20 mg kg-1 or 37.03%), from the respective controls. Mycorrhization alleviated Cu toxicity, most notably in the roots, where interactive effects were observed under application of AM fungi and Cu-based NPs/compounds for root biomass and length. An interactive effect found between the absence of AM fungi and presence of Cu-based NPs/compounds resulted in an influx of leaf Na content (0.70-1.13 mg kg-1, or 219.74-355.07%, increase from the corresponding control), which can be seen as an indicator of Cu-induced stress. Overall, bulk Cu-based compounds had the greatest impact over nano or ionic Cu-based compounds, with interactive effects in root accumulation of Cu (decrease by AM fungi + bulk Cu) and leaf accumulation of Mg and Mn (decrease by AM fungi + bulk Cu). Our research confirms that (1) Cu-based NPs/compounds can be phytotoxic to spearmint plants and (2) inoculation with AM fungi can alleviate Cu toxicity to spearmint. This study demonstrates that plant-microbe interactions could improve crop productivity and provide environmental benefits, emphasizing the need for risk assessment of crop systems incorporating symbiotic microorganisms.
BACKGROUND
Natural dihydrocarvone has been widely used in the food, cosmetics, agrochemicals and pharmaceuticals industries because of its sensory properties and physiological effects. In our previous study, Klebsiella sp. O852 was shown to be capable of converting limonene to trans‐dihydrocarvone with high catalytic efficiency. Thus, it was essential to identify and characterize the functional genes involved in limonene biotransformation using genome sequencing and heterologous expression.
RESULTS
The 5.49‐Mb draft genome sequence of Klebsiella sp. O852 contained 5218 protein‐encoding genes. Seven candidate genes participating in the biotransformation of limonene to trans‐dihydrocarvone were identified by genome analysis. Heterologous expression of these genes in Escherichia coli BL21(DE3) indicated that 0852_GM005124 and 0852_GM003417 could hydroxylate limonene in the six position to yield carveol, carvone and trans‐dihydrocarvone. 0852_GM002332 and 0852_GM001602 could catalyze the oxidation of carveol to carvone and trans‐dihydrocarvone. 0852_GM000709, 0852_GM001600 and 0852_GM000954 had high carvone reductase activity toward the hydrogenation of carvone to trans‐dihydrocarvone.
CONCLUSION
The results obtained in the present study suggest that the seven genes described above were responsible for converting limonene to trans‐dihydrocarvone. The present study contributes to providing a foundation for the industrial production of trans‐dihydrocarvone in microbial chassis cells using synthetic biology strategies. © 2021 Society of Chemical Industry.
Background: (-)-Carveol (p-Mentha-6,8-dien-2-ol) is a monocyclic monoterpenic alcohol, present in essential oils of plant species such as Cymbopogon giganteus, Illicium pachyphyllum and in spices such as Carum carvi (cumin). Pharmacological studies report its antitumor, antimicrobial, neuroprotective, vasorelaxant, antioxidant and anti-inflammatory activity.
Hypothesis/Purpose: The objective of this study was to evaluate the acute non-clinical oral toxicity, gastroprotective activity of monoterpene (-)-Carveol in animal models and the related mechanisms of action.
Methods: Acute toxicity was assessed according to OECD guide 423 in mice. Ethanol, stress, NSAIDs and pylorus ligation-induced gastric ulcer models were used to investigate antiulcer properties. The related mechanisms of action were using the ethanol-gastric lesions protocol.
Results: (-)-Carveol has low toxicity, with a lethal dose 50% (LD50) equal to or greater than 2,500 mg/kg according to OECD guide nº 423. In all gastric ulcer induction methods evaluated, (-)-Carveol (25, 50, 100 and 200 mg/kg, p.o.) significantly reduced the ulcerative lesion in comparison with the respective control groups. To investigate the mechanisms involved in the gastroprotective activity, the antisecretory or neutralizing of gastric secretion, cytoprotective, antioxidant and immunoregulatory effects were evaluated. In the experimental protocol of pylorus ligation-induced gastric ulcer, (-)-Carveol (100 mg/kg) reduced (p < 0.001) the volume of gastric secretion in both routes (oral and intraduodenal). The previous administration of blockers NEM (sulfhydryl groups blocker), L-NAME (nitric oxide synthesis inhibitor), glibenclamide (KATP channel blocker) and indomethacin (cyclo-oxygenase inhibitor), significantly reduced the gastroprotection exercised by (-)-Carveol, suggesting the participation of these pathways in its gastroprotective activity. In addition, treatment with (-)-Carveol (100 mg/kg) increased (p < 0.001) mucus adhered to the gastric wall. Treatment also increased (p < 0.001) levels of reduced glutathione (GSH), superoxide dismutase (SOD) and interleukin-10 (IL-10). It also reduced (p < 0.001) malondialdehyde (MDA), myeloperoxidase (MPO), interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) levels.
Conclusion: Thus, it is possible to infer that (-)-Carveol presents gastroprotective activity related to antisecretory, cytoprotective, antioxidant and immunomodulatory mechanisms.
This work evidenced the insecticidal activity of encapsulated Mentha spicata essential oil (EO) against Rhyzopertha dominica in presence of stored wheat grain and evaluated the residual EO amount in wheat grains after treatment. EO distribution in the different fractions recovered after grain milling was also determined. The mortality rate against R. dominica reached more than 90% and was dependent on the amount of EO released from the encapsulation matrix. The quantification of the two major compounds of EO, (R)-limonene and (R)-carvone, showed that wheat grains contained different amount depending on the storage conditions. When wheat grains were stored in open jars, the EO residual amount in grains was especially low (1.98mg/kg) compared to amount in closed jar (51.6 mg/kg). The flour resulting from milling contained lower amount of EO compounds in comparison with the bran fractions. The contact of wheat grains with EO clearly modified the native aromatic profile of the wheat flour as the most represented compounds were those belonging to the EO. In the native flour, ten volatile compounds, mainly alcohols and aldehydes due to oxidation of lipids were identified, which represented only 14% of the aromatic profile when the wheat grains were treated by EO. However, when the storage condition of grains mimics the silos conditions, the level of (R)-carvone, the major component of spearmint EO is found around 3 mg/kg of flour which was far below its currently use in bakery products.
This study was carried out to find eco-friendly control measures to protect wheat from the rice weevil (Sitophilus oryzae) for safe food. Efficiency of some synthetic monoterpenes (carvone, 1,8-cineole, cuminaldehyde, and linalool) as well as Yucca shedjera extract was evaluated under laboratory conditions against S. oryzae and compared to malathion regarding mortality and progeny development inhibition of S. oryzae adults. In addition, the mechanism of the toxic action of the tested control agents against S. oryzae was studied. The impact of the selected control agents on wheat grain quality was also evaluated. The examined control agents showed a high potential for controlling S. oryzae concerning the adult's mortality and offspring production. The insecticidal activity of the examined control agents against S. oryzae may be due to the disruption of acetylcholinesterase, alpha-amylase, and alkaline phosphatase activity. The quality of the stored wheat grains, which were treated with the tested control agents, did not change and was sometimes better compared to the untreated stored healthy grains. This study suggests that these control agents could be used to protect wheat grains in place of chemical insecticides.
The signaling pathways involved in age-related inflammation are increasingly recognized as targets for the development of preventive and therapeutic strategies. Our previous study elucidated the structure–activity relationship of monoterpene compounds derived from p-menthane as potential anti-inflammatory drugs and identified (S)-(+)-carvone as the most potent among the compounds tested. This study aims at identifying the molecular mechanism underlying the anti-inflammatory properties of (S)-(+)-carvone. The murine macrophage cell line, Raw 264.7, was stimulated with bacterial lipopolysaccharide (LPS) to simulate inflammation. Western blot was used to assess protein levels and post-translational modifications. The subcellular localization of NF-κB/p65 was visualized by immunocytochemistry. An in vitro fluorometric assay was used to measure Sirtuin-1 (SIRT1) activity. (S)-(+)-carvone inhibited LPS-induced JNK1 phosphorylation, but not that of p38 and ERK1/2 and also did not affect the phosphorylation and degradation of the NF-κB inhibitor, IκB-α. Accordingly, (S)-(+)-carvone did not affect LPS-induced phosphorylation of NF-κB/p65 on Ser536 and its nuclear translocation, but it significantly decreased LPS-induced IκB-α resynthesis, a NF-κB-dependent process, and NF-κB/p65 acetylation on lysine (Lys) 310. Deacetylation of that Lys residue is dependent on the activity of SIRT1, which was found to be increased by (S)-(+)-carvone, while its protein levels were unaffected. Taken together, these results show that (S)-(+)-carvone is a new SIRT1 activator with the potential to counteract the chronic low-grade inflammation characteristic of age-related diseases.
Essential oils (EOs) from Citrus are the main by-product of Citrus-processing industries. In addition to food/beverage and cosmetic applications, citrus EOs could also potentially be used as an alternative to antibiotics in food-producing animals. A commercial citrus EO—Brazilian Orange Terpenes (BOT)—was fractionated by vacuum fractional distillation to separate BOT into various fractions: F1, F2, F3, and F4. Next, the chemical composition and biological activities of BOT and its fractions were characterized. Results showed the three first fractions had a high relative amount of limonene (≥10.86), even higher than the whole BOT. Conversely, F4 presented a larger relative amount of BOT’s minor compounds (carvone, cis-carveol, trans-carveol, cis-p-Mentha-2,8-dien-1-ol, and trans-p-Mentha-2,8-dien-1-ol) and a very low relative amount of limonene (0.08–0.13). Antibacterial activity results showed F4 was the only fraction exhibiting this activity, which was selective and higher activity on a pathogenic bacterium (E. coli) than on a beneficial bacterium (Lactobacillus sp.). However, F4 activity was lower than BOT. Similarly, F4 displayed the highest antioxidant activity among fractions (equivalent to BOT). These results indicated that probably those minor compounds that detected in F4 would be more involved in conferring the biological activities for this fraction and consequently for the whole BOT, instead of the major compound, limonene, playing this role exclusively
Terpenes—a diverse group of secondary metabolites—constitute the largest class of natural products abundant in almost every plant species. The properties of concrete terpenes and essential oils have been intensively studied due to their widespread use in the pharmaceutical, food and cosmetics industries. Despite the popularity of these aromatic compounds, their derivatives, terpenoids, are still not comprehensively characterized despite exhibiting potent bioactive properties. This review aims to assess the anticancer properties of selected monoterpenes including carvone, carvacrol, perillyl alcohol, perillaldehyde, limonene, menthol and their derivatives while also evaluating potential applications as novel anticancer treatments. Special attention is paid to functional groups that improve the bioactivity of monoterpene molecules. This review also covers the therapeutic potential of deep eutectic solvents that contain monoterpene substances. Taken together, the literature supports the use of monoterpene derivatives in the development of new alternatives for disease treatment and prevention.
Flavors and fragrances have high commercial value in the food, cosmetic, chemical and pharmaceutical industries. It is interesting to investigate the isolation and characterization of new microorganisms with the ability to produce flavor compounds. In this study, a new strain of Klebsiella sp. O852 (accession number CCTCC M2020509) was isolated from decayed navel orange (Citrus sinensis (L.) Osbeck), which was proved to be capable of converting limonene to trans-dihydrocarvone. Besides, the optimization of various reaction parameters to enhance the trans-dihydrocarvone production in shake flask was performed for Klebsiella sp. O852. The results showed that the yield of trans-dihydrocarvone reached up to 1 058 mg/L when Klebsiella sp. O852 was incubated using LB-M medium for 4 h at 36 °C and 150 rpm, and the biotransformation process was monitored for 36 h after adding 1680 mg/L limonene/ethanol (final ethanol concentration of 0.8% (v/v)). The content of trans-dihydrocarvone increased 16 times after optimization. This study provided a basis and reference for producing trans-dihydrocarvone by biotransformation.
This study was conducted to identify the volatile compounds of Mentha × smithiana essential oil (MSEO) and evaluate its antioxidant and antibacterial potential. The essential oil (EO) content was assessed by gas chromatography–mass spectrometry (GC-MS). Carvone (55.71%), limonene (18.83%), trans-carveol (3.54%), cis-carveol (2.72%), beta-bourbonene (1.94%), and caryophyllene oxide (1.59%) were the main identified compounds. The MSEO displayed broad-spectrum antibacterial effects and was also found to be the most effective antifungal agent against Candida albicans and Candida parapsilosis. The antioxidant activity of MSEO was tested against cold-pressed sunflower oil by peroxide, thiobarbituric acid, 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), and β-carotene/linoleic acid bleaching methods. The EO showed strong antioxidant effects as reflected by IC50 values of 0.83 ± 0.01 mg/mL and relative antioxidative activity of 87.32 ± 0.03% in DPPH and β-carotene/linoleic acid bleaching assays, respectively. Moreover, in the first 8 days of the incubation period, the inhibition of primary and secondary oxidation compounds induced by the MSEO (0.3 mg/mL) was significantly stronger (p
Medicinal plants are considered colossal producers of bioactive therapeutics agents. The genus Mentha possesses commercial values owing to its aromatic species. Despite its traditional applications in food flavoring, Mentha spp. are widely used for treating not only cold and fever but also gastro-intestinal and cardiovascular disorders as folk medicines. It has revealed a plethora of biological traits viz. antimicrobial, antioxidant, anticancer, anti-ulcer, anti-diabetic, insecticidal, and anti-inflammatory activities. Generally, the presence of bioactive phytochemicals is the prime reason for the traditional pharmacological activities of Mentha spp. A rich source of potential phytoconstituents of Mentha spp. is an important agent for designing nutra‐pharmaceuticals. The current review paper discusses the different phytochemical, traditional medicinal features, and prime therapeutic properties of some of the most commonly used Mentha spp. Also, this paper summarizes the role of various metabolites of Mentha towards the development of therapeutic drugs in the future.
The immature lymphoid cells with chromosomal structural and numerical abnormalities cause the acute lymphoblastic leukemia (ALL). This hematologic disorder constitutes about 25% of cancer prognosis among children and adolescents. D-Carvone, a monocyclic monoterpene obtained from the essential oils extracted from plants is reported to possess the various biological activities. The present study was aimed to investigate the anticancer potential of D-Carvone against the human leukemic Molt-4 cells. The cytotoxicity of DCarvone was analyzed by MTT assay. The level of lipid peroxidation and antioxidants were determined. The intracellular ROS, MMP and apoptosis were demonstrated by fluorescent staining techniques. The MTT assay revealed that the D-Carvone treatment suppressed the viability of Molt-4 cells and the IC50 was determined at 20 μM/ml. The D-Carvone treatment was increased the oxidative stress and reduced the level of antioxidants in the Molt-4 cell lines. The increased intracellular ROS, apoptotic cell death, and diminished MMP was noted in the D-Carvone treatment. In the Molt-4 cells, D-carvone induced the apoptosis in a time and dose dependent manner by the activation of caspases-8, -9 and -3. Thus, data provide insights for the clinical application of D-Carvone in the treatment of blood cancer Molt-4 cells. Our study suggests the therapeutic potential D-Carvone for the treatment of leukemia in future.
Acetaminophen (N-acetyl p-aminophenol or APAP) is used worldwide for its antipyretic and anti-inflammatory potential. However, APAP overdose sometimes causes severe liver damage. In this study, we elucidated the protective effects of carveol in liver injury, using molecular and in silico approaches. Male BALB/c mice were divided into two experimental cohorts, to identify the best dose and to further assess the role of carveol in the nuclear factor E2-related factor; nuclear factor erythroid 2; p45-related factor 2 (Nrf2) pathway. The results demonstrated that carveol significantly modulated the detrimental effects of APAP by boosting endogenous antioxidant mechanisms, such as nuclear translocation of Nrf2 gene, a master regulator of the downstream antioxidant machinery. Furthermore, an inhibitor of Nrf2, called all-trans retinoic acid (ATRA), was used, which exaggerated APAP toxicity, in addition to abrogating the protective effects of carveol; this effect was accompanied by overexpression of inflammatory mediators and liver = 2ltoxicity biomarkers. To further support our notion, we performed virtual docking of carveol with Nrf2-keap1 target, and the resultant drug-protein interactions validated the in vivo findings. Together, our findings suggest that carveol could activate the endogenous master antioxidant Nrf2, which further regulates the expression of downstream antioxidants, eventually ameliorating the APAP-induced inflammation and oxidative stress.
Essential oils or volatile oils are natural products that have a large series of uses in the food and cosmetic sectors. According to their intended use, essential oils are subjected to various European guidelines that aim to protect the health and safety of consumers. Volatile oils present important biological activities, some of the most known being their antimicrobial properties, but other potential therapeutic indications for such products have been more recently suggested, as well. However, they are not necessarily harmless and can present an important sensitizing potential. Essential oils have been administered through different routes, including inhalations and skin applications, in the treatment of stress and anxiety. Regardless of the route of administration, aromatherapy deeply relies on the sense of smell and its connection with the limbic system. Nevertheless, outside of the principles of aromatherapy, numerous scientific studies have revealed their potential beneficial implications in Alzheimer’s and other neurological disorders. © 2020, Romanian Society for Pharmaceutical Sciences. All rights reserved.
Strawberry has a short postharvest shelf life, mainly because of the gray mold caused by Botrytis cinerea. The chemical composition and antifungal activities of essential oils from Mentha piperita, Cymbopogon martinii, Cinnamomum camphora, Mentha spicata, and their binary mixtures against B. cinerea were evaluated by different in vitro methods, and also in vivo in vapor-phase on inoculated strawberries. The major components present in M. piperita essential oil were menthol (45.37%), menthone (20.13%), isomenthone (16.94%), menthyl acetate (3.81%), pulegone (1.89%), α-terpinene (1.88%), isopulegol (1.83%), neoisomenthol (1.19%), and α-terpineol (1.08%), in C. martinii essential oil were geraniol (83.82%), geranyl acetate (7.49%), linalool (2.48%), and caryophyllene (1.33%), in C. camphora essential oil were linalool (98.39%), and M. spicata essential oil were carvone (61.71%), limonene (20.22%), 1,8-cineole (5%), sabinene (2.28%), cis-dihydrocarvone (1.63%), and α-thujene (1.4%). The highest antifungal activity in vitro was presented by M. spicata and C. martinii essential oils by the direct contact, vapor contact, spore germination, and micro-well dilution methods. In vivo, strawberries treated with the vapor of M. spicata and C. martinii essential oils showed a reduction in disease incidence and severity. At a 10% concentration, M. spicata and C. martinii showed a reduction of 100% and 83% in the disease incidence, respectively. Thus, the M. spicata and C. martinii essential oils may be potential alternatives for the control of B. cinerea in postharvest fresh strawberries.
The aim of this study was to determine, first, the chemical composition of Aloysia polystachya (Griseb) Moldenke essential oil, from leaves harvested in central Chile; and second, its antioxidant and cytotoxic activity. Eight compounds were identified via gas chromatography–mass spectrometry (GC–MS) analyses, with the most representative being R-carvone (91.03%), R-limonene (4.10%), and dihydrocarvone (1.07%). For Aloysia polystachya essential oil, antioxidant assays (2,2-diphenyl-1-picrylhydrazyl (DPPH), H2O2, ferric reducing antioxidant power (FRAP), and total reactive antioxidant potential (TRAP)) showed good antioxidant activity compared to commercial antioxidant controls; and anti-proliferative assays against three human cancer cell lines (colon, HT-29; prostate, PC-3; and breast, MCF-7) determined an IC50 of 5.85, 6.74, and 9.53 µg/mL, and selectivity indices of 4.75, 4.12, and 2.92 for HT-29, PC-3, and MCF-7, respectively. We also report on assays with CCD 841 CoN (colon epithelial). Overall, results from this study may represent, in the near future, developments for natural-based cancer treatments.
To explore the present treatment strategies for ischemic stroke lowered by ischemia-reperfusion (I/R) injury, to hypothesize the effect of d-Carvone on cerebral I/R brain injury induced neuroinflammation through oxidative stress markers mechanism via NRLP3 and TLR4 marker expressions in rat model. The rats were divided into four groups: Sham, I/R vehicle, I/R + D-carvone (10 mg/kg/bw), I/R + D-carvone (20 mg/kg/bw). Supplementation of d-carvone at dose of 10 and 20 m/kg/bw increased the water content, reduced infract volume, attenuated neurological score depicts, furthermore it had antioxidative, anti-inflammatory, and anti-apoptotic effects against cerebral I/R brain injury. In the brain tissues decreased proinflammatory cytokines IL-1β and TNF-α reduced interleukins IL-6, IL-4, IL-10 & VEGF dose dependently, and mRNA expressions of NLRP3, caspase -1, TNF-α, ASC, IL-1β and TLR3 down regulated in cerebral I/R induced rats. Finally d- carvone can successfully improve the cerebral I/R induced rats neuroinflammation, in the hippocampus and cortical areas of the brain finally reduces cerebral I/R induced injury. These results were hypothesized that d-carvone contributed to cerebral stroke associated with the TLR3, giving an excellent therapeutic approach for cerebral I/R brain injury.
Background
Carveol is a natural drug product present in the essential oils of orange peel, dill, and caraway seeds. The seed oil of Carum Carvi has been reported to be antioxidant, anti-inflammatory, anti-hyperlipidemic, antidiabetic, and hepatoprotective.
Methods
The antidiabetic potential of carveol was investigated by employing in-vitro, in-vivo, and in-silico approaches. Moreover, alpha-amylase inhibitory assay and an alloxan-induced diabetes model were used for in-vitro and in-vivo analysis, respectively.
Results
Carveol showed its maximum energy values (≥ -7 Kcal/mol) against sodium-glucose co-transporter, aldose reductase, and sucrose-isomaltase intestinal, whereas it exhibited intermediate energy values (≥ -6 Kcal/mol) against C-alpha glucosidase, glycogen synthase kinases-3β, fructose-1,6-bisphosphatase, phosphoenolpyruvate carboxykinase, and other targets according to in-silico analysis. Similarly, carveol showed lower energy values (≥ 6.4 Kcal/mol) against phosphoenolpyruvate carboxykinase and glycogen synthase kinase-3β. The in-vitro assay demonstrated that carveol inhibits alpha-amylase activity concentration-dependently. Carveol attenuated the in-vivo alloxan-induced (1055.8 µMol/Kg) blood glucose level in a dose- and time-dependent manner (days 1, 3, 6, 9, and 12), compared to the diabetic control group, and further, these results are comparable with the metformin positive control group. Carveol at 394.1 µMol/Kg improved oral glucose tolerance overload in rats compared to the hyperglycemic diabetic control group. Moreover, carveol also attenuated the glycosylated hemoglobin level along with mediating anti-hyperlipidemic and hepatoprotective effects in alloxan-induced diabetic animals.
Conclusions
This study reveals that carveol exhibited binding affinity against different targets involved in diabetes and has antidiabetic, anti-hyperlipidemic, and hepatoprotective actions.
Ischemic stroke is a severe neurological disorder with a high prevalence rate in developed countries. It is characterized by permanent or transient cerebral ischemia and it activates syndrome of pathological events such as membrane depolarization, glutamate excitotoxicity, and intracellular calcium buildup. Carveol is widely employed as anti-inflammatory and antioxidant in traditional Chinese medicine. In the present study, the neuroprotective effects of post-treated carveol were demonstrated against transient middle cerebral artery occlusion (MCAO) induced focal ischemic cerebral injury. Male Sprague Dawley (SD) rats were subjected to two different experimental protocols to determine the dose and effects of carveol, and to demonstrate the underlying role of the nuclear factor E2-related factor (Nrf2) pathway. Our results showed that MCAO induced marked neuronal injury in the ipsilateral cortex and striatum associated with higher inflammatory cytokines expression, along with apoptotic markers such as caspase-3 and the phosphorylated c-Jun N-terminal kinase (JNK). Furthermore, MCAO induced a marked increase in oxidative stress as evidenced by high lipid peroxidase (LPO) content accompanied by the depressed antioxidant system. Carveol significantly reversed the oxidative stress and downregulated inflammatory cascades by enhancing endogenous antioxidant mechanisms including the Nrf2 gene, which critically regulates the expression of several downstream antioxidants. Further, to determine the possible involvement of Nrf2 in carveol mediated neuroprotection, we antagonized Nrf2 by all-trans retinoic acid (ATRA), and such treatment abrogated the protective effects of carveol accompanied with exaggerated neuronal toxicity as demonstrated by higher infarction area. The target effects of carveol were further supported by molecular docking analysis of drug–protein interactions. Together, our findings suggest that carveol could activate endogenous master anti-oxidant Nrf2, which further regulates the expression of downstream antioxidants, eventually ameliorating MCAO-induced neuroinflammation and neurodegeneration.
α-Terpineol (CAS No. 98-55-5) is a tertiary monoterpenoid alcohol widely and commonly used in the flavors and fragrances industry for its sensory properties. It is present in different natural sources, but its production is mostly based on chemical hydration using α-pinene or turpentine. Moreover, many bioprocesses for the microbial production of α-terpineol via biotransformation of monoterpenes (limonene, α- and β-pinenes) are also available in the literature. In addition to its traditional use, α-terpineol has also been evaluated in other application fields (e.g., medical), since some biological properties other than aroma, such as antioxidant, anti-inflammatory, antiproliferative, antimicrobial, and analgesic effects, among others, have been attributed to this compound. Therefore, this review presents an original compilation of data regarding the production (extraction directly from nature; chemical synthesis; via biotechnological process), the chemical and biological properties, and the current market and novel applications of α-terpineol to guide further research in this area. Considering the information presented, we believe that α-terpineol applications may transcend the flavors and fragrances industry in the future.
Mint species are widely used in traditional and conventional medicine as topical analgesics for osteoarthritic pain and for disorders of the gastrointestinal and respiratory tracts which are all associated with chronic inflammation. To identify the structural determinants of anti-inflammatory activity and potency which are required for chemical optimization towards development of new anti-inflammatory drugs, a selected group of monoterpenes especially abundant in mint species was screened by measuring bacterial lipopolysacharide (LPS)-induced nitric oxide (NO) production in murine macrophages. Nine compounds significantly decreased LPS-induced NO production by more than 30%. IC 50 values were calculated showing that the order of potency is: (S)-(+)-carvone > (R)-(−)-carvone > (+)-dihydrocarveol > (S)-8-hydroxycarvotanacetone > (R)-8-hydroxycarvotanacetone > (+)-dihydrocarvone > (−)-carveol > (−)-dihydrocarveol > (S)-(-)-pulegone. Considering the carbon numbering relative to the common precursor, limonene, the presence of an oxygenated group at C6 conjugated to a double bond at C1 and an isopropenyl group and S configuration at C4 are the major chemical features relevant for activity and potency. The most potent compound, (S)-(+)-carvone, significantly decreased the expression of NOS2 and IL-1β in macrophages and in a cell model of osteoarthritis using primary human chondrocytes. (S)-(+)-carvone may be efficient in halting inflammation-related diseases, like osteoarthritis.
Alzheimer’s disease (AD) could be considered a multifactorial neurodegenerative disorder characterized by the accumulation of the β-amyloid-peptide (Aβ) within the brain leading to cognitive deficits, oxidative stress, and neuroinflammation. The present work was carried out to investigate the neuroprotective effect of (-)-cis-carveol (1% and 3%, for 21 days) against the β-amyloid-peptide 1-42- (Aβ1-42-) induced AD. Twenty-five rats were divided into five groups (n=5/group): the first group—control (sham-operated); the second group—Aβ1-42 (1 mM) that received donepezil treatment (5 mg/kg, as the positive reference drug in the Y-maze and the radial arm maze tests); the third group—Aβ1-42 (1 mM); the fourth and fifth groups—Aβ1-42 (1 mM) that received (-)-cis-carveol treatment groups (1% and 3%). The results of this study demonstrated that (-)-cis-carveol improved Aβ1-42-induced memory deficits examined by using Y-maze and radial arm maze in vivo tests. Also, the biochemical analyses of the hippocampus homogenates showed that (-)-cis-carveol reduced hippocampal oxidative stress caused by Aβ1-42. Our results suggested that the use of (-)-cis-carveol may be suitable for decreasing AD-related symptoms.
Investigations have indicated that storage pests pose a great threat to global food security by damaging food crops and other food products derived from plants. Essential oils are proven to have significant effects on a large number of stored grain insects. This study evaluated the contact toxicity and fumigant activity of the essential oil extract from the aerial parts of Elsholtzia ciliata and its two major biochemical components against adults and larvae of the food storage pest beetle Tribolium castaneum. Gas chromatography–mass spectrometry analysis revealed 16 different components derived from the essential oil of E. ciliata, which included carvone (31.63%), limonene (22.05%), and α-caryophyllene (15.47%). Contact toxicity assay showed that the essential oil extract exhibited a microgram-level of killing activity against T. castaneum adults (lethal dose 50 (LD50) = 7.79 μg/adult) and larvae (LD50 = 24.87 μg/larva). Fumigant toxicity assay showed LD50 of 11.61 mg/L air for adults and 8.73 mg/L air for larvae. Carvone and limonene also exhibited various levels of bioactivity. A binary mixture (2:6) of carvone and limonene displayed obvious contact toxicity against T. castaneum adults (LD50 = 10.84 μg/adult) and larvae (LD50 = 30.62 μg/larva). Furthermore, carvone and limonene exhibited synergistic fumigant activity against T. castaneum larvae at a 1:7 ratio. Altogether, our results suggest that E. ciliata essential oil and its two monomers have a potential application value to eliminate T. castaneum.
Lung inflammation is a common cause of health problem and death among adults and children. Antioxidant compounds have the capability to overcome this complication. This study targets to examine the anti-inflammatory and defensive role of D-carvone on lipopolysaccharide (LPS)-initiated lung damage in mice. Male BALB/c mice (n = 8) received intragastric feeding of D-carvone (25 and 50 mg/kg b.w.) or dexamethasone (5 mg/kg b.w.) an hour before intranasal instillation of LPS (20 µg). Seven hours after LPS instillation, the bronchoalveolar lavage fluid (BALF), blood serum, and tissue samples of lung were studied for the levels of inflammatory cells, antioxidant enzymes, pro-inflammatory cytokines, and histopathological changes. D-carvone significantly alleviated (p < 0.05) the lung damage caused by LPS by reducing the lung wet-to-dry (W/D) ratio along with the amount of total cells, macrophages, and neutrophils in BALF (p < 0.05). The serum TNF-α, IL-1β, and IL-6 were remarkably reduced (p < 0.05) in D-carvone treated mice. Histopathological derangements because of LPS-initiated lung damage were altered by D-carvone. The results of D-carvone were comparable with the positive control dexamethasone. Pre-treatment of D-carvone significantly provided anti-inflammatory and protective effect in LPS-instigated lung damage. Together, these findings acknowledge the use of D-carvone as preventive agent for lung damage and inflammation. Further research on the pharmacokinetics, pathway and mechanism of action of D-carvone are necessary to promote D-carvone as a commercial anti-inflammatory drug.
Candida is a genus of yeasts and is the most common cause of fungal infections worldwide. However, only a few antifungal drugs are currently available for the treatment of Candida infections. In the last decade, terpenophenols have attracted much attention because they often possess a variety of biological activities. In the search for new antifungals, eight carveoylphenols were synthesized and characterized by spectroscopic analysis. By using the broth microdilution assay, the compounds were evaluated for antifungal activities in vitro against four human pathogenic yeast, and structure–activity relationships (SAR) were derived. Noteworthy, in this preliminary study, compounds 5 and 6, have shown a significant reduction in the growth of all Candida strains tested. Starting from these preliminary results, we have designed the second generation of analogous in this class, and further studies are in progress in our laboratories.
Skin penetration/permeation enhancers are compounds that improve (trans)dermal drug delivery. We designed hybrid terpene-amino acid enhancers by conjugating natural terpenes (citronellol, geraniol, nerol, farnesol, linalool, perillyl alcohol, menthol, borneol, carveol) or cinnamyl alcohol with 6-(dimethylamino)hexanoic acid through a biodegradable ester linker. The compounds were screened for their ability to increase the delivery of theophylline and hydrocortisone through and into human skin ex vivo. The citronellyl, bornyl and cinnamyl esters showed exceptional permeation-enhancing properties (enhancement ratios up to 82) while having low cellular toxicities. The barrier function of enhancer-treated skin (assessed by transepidermal water loss and electrical impedance) recovered within 24 h. Infrared spectroscopy suggested that these esters fluidized the stratum corneum lipids. Furthermore, the citronellyl ester increased the epidermal concentration of topically applied cidofovir, which is a potent antiviral and anticancer drug, by 15-fold. In conclusion, citronellyl 6-(dimethylamino)hexanoate is an outstanding enhancer with an advantageous combination of properties, which may improve the delivery of drugs that have a limited ability to cross biological barriers.
Anethum graveolens L. (A. graveolens) commonly known as dill, is an essential oil bearing plant extensively being used in traditional system of medicine. However, the reports on the components and biological responses of A. graveolens essential oil (AG-EO) from Saudi Arabia are scarce. The present study was designed to explore the presence of basic constituents and apoptosis induced by AG-EO in HepG2 cells. The constituents in AG-EO was analyzed by Gas chromatography-Mass spectroscopy (GC–MS). Cytotoxicity of AG-EO was measured by MTT assay and cell cycle arrest and apoptosis assays were conducted by using flow cytometer. Based on GC–MS analysis, the main constituents present in AG-EO were carvone (53.130%), dillapole (25.420%), dihydrocarvone 2 (11.350%) and dihydrocarvone 1 (6.260%). A few other minor components were also identified viz. cis-dihydrocarveol (0.690%), limonene (0.580%), isodihydrocarveol (0.370%), myristicin (0.210%) and cis-arsone (0.190%). The cytotoxicity results showed that AG-EO decrease the cell viability and inhibit the cell growth of HepG2 cells in a concentration-dependent manner. The inhibitory activity of AG-EO was found with IC50 = 59.6 ± 5.64. The cell cycle arrest results showed that HepG2 cells exposed to AG-EO exhibited an increase in G2/M and pre-G1 cell population after 24 h exposure. Furthermore, the flow cytometry data revealed the primarily activation of cell death by apoptosis manners in HepG2 cells exposed to AG-EO. Overall, results from this study highlighted the anticancer potential of AG-EO, which could be considered as a new agent for the management of hepatocellular carcinoma. Keywords: A. graveolens, Essential oil, Hepatocellular carcinoma, Anticancer, Cell cycle arrest, Apoptosis
The rate-limiting enzyme of the 2-methyl-d-erythritol-4-phosphate (MEP) terpenoid biosynthetic pathway, 1-deoxy-d-xylulose-5-phosphate reductoisomerase (DXR), provides the perfect target for screening new antibacterial substances. In this study, we tested the DXR inhibitory effect of 35 plant essential oils (EOs), which have long been recognized for their antimicrobial properties. The results show that the EOs of Zanbthoxylum bungeanum (ZB), Schizonepetae tenuifoliae (ST), Thymus quinquecostatus (TQ), Origanum vulgare (OV), and Eugenia caryophyllata (EC) displayed weak to medium inhibitory activity against DXR, with IC50 values of 78 μg/mL, 65 μg/mL, 59 μg/mL, 48 μg/mL, and 37 μg/mL, respectively. GC-MS analyses of the above oils and further DXR inhibitory activity tests of their major components revealed that eugenol (EC) and carvacrol (TQ and OV) possess medium inhibition against the protein (68.3% and 55.6%, respectively, at a concentration of 20 μg/mL), whereas thymol (ST, TQ, and OV), carveol (ZB), and linalool (ZB, ST, and OV) only exhibited weak inhibition against DXR, at 20 μg/mL (23%−26%). The results add more details to the antimicrobial mechanisms of plant EOs, which could be very helpful in the direction of the reasonable use of EOs in the food industry and in the control of phytopathogenic microbials.
Culinary herbs and spices have been used as both food flavoring and food preservative agents for centuries. Moreover, due to their known and presumptive health benefits, herbs and spices have also been used in medical practices since ancient times. Some of the health effects attributed to herbs and spices include antioxidant, anti-microbial, and anti-inflammatory effects as well as potential protection against cardiovascular disease, neurodegeneration, type 2 diabetes, and cancer. While interest in herbs and spices as medicinal agents remains high and their use in foods continues to grow, there have been remarkably few studies that have attempted to track the dietary intake of herbs and spices and even fewer that have tried to find potential biomarkers of food intake (BFIs). The aim of the present review is to systematically survey the global literature on herbs and spices in an effort to identify and evaluate specific intake biomarkers for a representative set of common herbs and spices in humans. A total of 25 herbs and spices were initially chosen, including anise, basil, black pepper, caraway, chili pepper, cinnamon, clove, cumin, curcumin, dill, fennel, fenugreek, ginger, lemongrass, marjoram, nutmeg, oregano, parsley, peppermint and spearmint, rosemary, saffron, sage, tarragon, and thyme. However, only 17 of these herbs and spices had published, peer-reviewed studies describing potential biomarkers of intake. In many studies, the herb or spice of interest was administrated in the form of a capsule or extract and very few studies were performed with actual foods. A systematic assessment of the candidate biomarkers was also performed. Given the limitations in the experimental designs for many of the published studies, further work is needed to better evaluate the identified set of BFIs. Although the daily intake of herbs and spices is very low compared to most other foods, this important set of food seasoning agents should not be underestimated, especially given their potential benefits to human health.
Electronic supplementary material
The online version of this article (10.1186/s12263-019-0636-8) contains supplementary material, which is available to authorized users.
The structural integrity and excellent immune system of the skin makes it a protective covering, inspite of its exposure to hazardous compounds. In the present study, the chemopreventive efficacy of D-carvone was studied in 7, 12-dimethylbenz[a]anthracene (DMBA) induced skin carcinogenesis. DMBA (25 μg in 0.1 m L⁻¹acetone) was used to induce skin cancer in Swiss albino mice. Animals were randomly divided into six groups of six animals in each. Different concentrations of D-carvone (10, 20, 30 mg/kg body weight) were used to assess its anticancer effect. Tumor incidence, tumor volume, tumor burden, histological examination and levels of phase I and phase II detoxification agents were analyzed in experimental animals. Further, expression of p53 and various apoptotic proteins including- Bcl-2, Bax was analyzed using immunohistochemistry and enzymatic expression of apoptotic proteins caspase-3 and caspase-9 was carried out by using ELISA. We observed 100% tumor incidence in DMBA-painted animals and our results showed that D-carvone at 20 mg dose significantly prevents skin carcinogenesis. Our results also showed decreased levels of phase I enzymes (Cyt P450 and-Cyt b5) with increased levels of phase II enzymes (GR, GST and GSH) and increased expression of Bax, caspase-3 and caspase-9 with decreased expression of mutated p53 and Bcl-2 in animals treated with DMBA and D-carvone at 20 mg dose. The results of the present study suggest that D-carvone can be used as a chemopreventive agent against skin cancer, as it induces apoptosis in cancer. However, further studies are warranted to check chemopreventive efficacy of D-carvone on cell proliferation, angiogenesis, and metastasis before going to human trial.
In the present study, Dill (Anethum graveolens) seed essential oil, its nonpolar and polar fractions, compounds isolated and derivatized were evaluated for their antioxidant potential using different in vitro assays. The major compounds carvone, limonene, and camphor were isolated from dill seed essential oil using column chromatography and characterized using spectroscopic techniques. Among all the tested components for antioxidant activity, carveol and perillyl alcohol were most effective (IC50 values < 0.16 mg/ml), whereas camphor was least effective (IC50 values > 10 mg/ml). All the tested compounds exhibited lower antioxidant potential than the standard.
Practical applications
Oxidation of food products was delayed by compounds known as antioxidants. The use of synthetic antioxidant is restricted because of carcinogenicity in human servings and plant‐based natural antioxidant are preferred due to safety and less toxicity. The aim of this in vitro study was to assess the antioxidant activity of the different constituents of dill seed essential oil. The present study revealed that carvone and its derivatives are potent scavengers of free radicals which might be due to the presence of unsaturated hydroxyl group. Thus, natural antioxidants are the important source of alternative medicines and natural therapy in the pharmaceutical industry.
This study evaluated the chemical components of spearmint essential oil, and determined individually the efficacy of spearmint EO and its major constituents, and their mutual binary combination against Reticulitermes dabieshanensis. We also evaluated the activities of esterases (ESTs), glutathione S-transferases (GST) and Acetylcholinesterase (AChE) enzymes in treated insects. GC–MS analysis showed that the major constituents of spearmint EO were carvone (52.25 %), limonene (19.78 %), and dihydrocarvone (11.1 %). In fumigant toxicity assay, the spearmint EO achieved a LC50 value of 0.194 μl/L. The three major constituents, carvone, dihydrocarvone, and limonene were most effective against R. dabieshanensis, with LC50 values of 0.074, 0.155, and 2.650 μl/L, respectively. The toxicity assay of binary mixtures of carvone + dihydrocarvone, carvone + limonene and limonene + dihydrocarvone in all the used ratios showed the three major constituents exhibited synergistic effects against R. dabieshanensis. Spearmint EO and its major constituents showed significantly stronger insecticidal efficacies at the high temperature, with rapid insecticidal action. The increased activity of ESTs and GST were observed, but with the decreased activity of AChE in all treatments. In vitro experiments, all treatments showed significant inhibition of AChE activity, except for dihydrocarvone, with IC50 values were 0.871, 2.405, 2.653 and 4.343 μl/mL for limonene, carvone, carvone + limonene and carvone + dihydrocarvone, respectively. The results showed that the insecticidal efficacy of spearmint EO can be attributed to the major component, possibly carvone, with strong AChE inhibition properties. Hence, spearmint EO and its bioactive constituents have the potential to be used as new environmentally safe insecticides for controlling R. dabieshanensis.
The existing information supports the use of this material as described in this safety assessment. Dihydrocarvyl acetate was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analogs dihydrocarveol (isomer unspecified) (CAS # 619-01-2) and acetic acid (CAS # 64-19-7) show that dihydrocarvyl acetate is not expected to be genotoxic. Data on read-across analogs isopulegol (CAS # 89-79-2) and acetic acid (CAS # 64-19-7 provide a calculated MOE >100 for the repeated dose toxicity endpoint. The reproductive and local respiratory toxicity endpoints were evaluated using the TTC for a Cramer Class I material, and the exposure to dihydrocarvyl acetate is below the TTC (0.03 mg/kg/day and 1.4 mg/day, respectively). Data from read-across analog 4-methyl-8-methylenetricyclo[3.3.1.(3,7)]decan-2-yl acetate (CAS # 122,760-85-4) provided dihydrocarvyl acetate a NESIL of 2500 μg/cm² for the skin sensitization endpoint. The phototoxicity/photoallergenicity endpoints were evaluated based on UV/Vis spectra; dihydrocarvyl acetate is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; dihydrocarvyl acetate was found not to be PBT as per the IFRA Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., PEC/PNEC), are <1.
The aims of this work were to point out the seasonal variation in chemical composition and evaluate the insecticidal activities of Mentha spicata and Thymus vulgaris essential oils against larvae of three moths Ectomyelois ceratoniae, Ephestia kuehniella and Plodia interpunctella. GC–MS analyses indicated that major components of M. spicata essential oil were carvone, 1, 8-cineole and limonene. However, linalool, camphor and γ-terpinene were the main compounds for T. vulgaris. Results showed that chemical composition varied with plant species, as well as seasons. On the other hand, results indicated that mortality percentages were highest during the summer season at the concentration 16 µl/l air. Thus, fumigant toxicity depends on insect species, plants, seasons and concentrations. Besides, E. kuehniella was more sensitive to both oils as compared to E. ceratoniae and P. interpunctella. The LC50 values were 0.29, 4.40 and 2.51 µl/l air, respectively, for M. spicata. Concerning T. vulgaris, the respective LC50 values were 0.062, 4.61 and 3.23 µl/l air for E. kuehniella, E. ceratoniae and P. interpunctella. Furthermore, for the most toxic season, LT50 values of M. spicata were 0.7, 5.2 and 3.2 days, respectively, for E. kuehniella, E. ceratoniae and P. interpunctella. Regarding T. vulgaris, LT50 values were 0.35, 6.5 and 4.58 days, respectively, for E. kuehniella, E. ceratoniae and P. interpunctella. Therefore, essential oils collected during summer season could be considered as an effective tool of control against moths of stored products.
Ethnopharmacology relevance
Mentha spicata L (Lamiaceae), commonly called Spearmint, is wildly cultivated worldwide for its remarkable aroma and commercial value. In addition to traditional foods flavouring agent, M. spicata is well known for its traditional medicinal uses, particularly for the treatment of cold, cough, asthma, fever, obesity, jaundice and digestive problems.
Aim of the review: This review aims to critically appraise scientific literature regarding the traditional uses, bioactive chemical constituents and pharmacological activities of M. spicata.
Materials and methods
A review of the literature information on M. spicata was searched from scientific electronic search databases (Google Scholar, PubMed, Web of Science, ACS, Science Direct, Taylor and Francis, Wiley, Springer and SCOPUS. Structures for secondary metabolites were confirmed using PubChem and ChemSpider.
Results
The studies conducted on either crude extracts, essential oil or isolated pure compounds from M. spicata had reported a varied range of biological effects including antibacterial, antifungal, antioxidant, hepatoprotective, antidiabetic, cytotoxic, anti-inflammatory, larvicidal activity, antigenotoxic potential and antiandrogenic activities. Phytochemical analysis of various parts of M. spicata revealed 35 chemical constituents, belonging to phenolic acids, flavonoids and lignans.
Conclusion
The review finding indicates that the pharmacological properties of M. spicata supported its traditional uses. The essential oils and extracts showed remarkable antimicrobial, antioxidant, anticancer, anti-inflammatory and hepatoprotective activities. However, more studies, especially in vivo experiments and clinical trials of the human to evaluate cellular and molecular mechanisms based pharmacological, bioactive effectiveness and safety investigation, should be undertaken in the future to provide stronger scientific proof for their traditional medicinal properties.
Foodborne, disease-causing microorganisms are increasingly resistant to commercial antibiotics. Thus, there is a need for the development of new agents capable of acting efficiently in the control of these pathogens. Terpenoids and phenylpropanoids stand out for having high biological activity and a broad spectrum of action. The objectives of thi study were to evaluate the antibacterial potential of limonene, β-citronellol, carvone, carvacrol, eugenol and trans-cinnamaldehyde and to investigate the mechanism of activity of these compounds against the bacteria Escherichia coli and Staphylococcus aureus. The terpene and phenylpropanoid compoundswere purchased and their antibacterial potential was assessed by macrodilution. The mechanism of action was verified by tests of potassium ion efflux, salt tolerance, extravasation of cellular contents, absorption of crystal violet and morphological changes analyzed by electron microscopy. Bacteriostatic and bactericidal effects caused by the compounds carvone, carvacrol, eugenol and transcinemaldehyde were observed in both species; antibacterial activity against only S. aureus was observed for β-citronelol and limonene. Reduced salt tolerance was found for strains of E. coli treated with carvacrol and S. aureus treated with β-citronelol. There was extravasation of cellular materials induced by treatments with carvone, carvacrol, eugenol and trans-cinnamaldehyde in both microorganisms. The absorption of crystal violet increased for E. coli after incubation with each treatment. Deleterious effects and morphological changes were observed. Therefore, the monoterpenes and phenylpropanoids under study are potentially applicable for antimicrobial use against E. coli and S. aureus, and the mechanism of action involves changes in membrane permeability without cell lysis.
Background/objectives:
Carvone, a flavoring agent, may cause allergic contact dermatitis. This study summarizes patch test reactions to carvone in patients tested by the North American Contact Dermatitis Group, 2009 to 2018.
Methods:
This was a retrospective analysis of patients positive to carvone (5% petrolatum). Demographics were compared with those of patients who were negative. Other analyses included reaction strength, clinical relevance, coreactivity with other fragrance/flavor allergens, and exposure sources.
Results:
Of 24,124 patients tested to carvone, 188 (0.78%) were positive. As compared with carvone-negative patients, carvone-positive patients were significantly more likely older than 40 years (P = 0.0284). Women (76.1%) and/or facial involvement (33.0%) were common in the carvone-positive group but not statistically different from carvone-negative patients; 73.3% (n = 138) of the reactions were currently relevant. Relevant sources were personal care products (46.3%, n = 87) and food (14.3%, n = 27). Coreactivity with other fragrance/flavor markers was present in 60.6% of carvone-positive patients, most commonly fragrance mix I (34.6%), balsam of Peru (24.5%), and cinnamic aldehyde (15.4%).
Conclusions:
Ten-year prevalence of carvone sensitivity was 0.78%. Most carvone-positive patients were female, were older than 40 years, and/or had facial dermatitis. Personal care products were the most common source. Two-fifths of carvone reactions would have been missed by relying on other fragrance/flavoring allergens.
Globally, gastric cancer is one of the leading cause of death. Surgical and chemotherapy constitute an important treatment regimen. Unfortunately, less than 20 persons out of 100 patients are live on almost 5 years. Hence, a nontoxic, effective and significantly enhancing novel therapeutic agent is required. d‐Carvone is a natural terpenoid present in the essential oils and abundant in the seeds of caraway, as well as known folk medication for diarrhea, acidity, and other gastric disorders. Nevertheless, the role of d‐carvone on gastric cancer and its underlying molecular mechanism resides enigmatic. Cells were treated with d‐carvone to find out the IC50 by MTT assay. This study shows that 20 and 25 μM d‐carvone has induced the reactive oxygen species production and mitochondrial membrane potential in gastric cancer AGS cells, which were evaluated by 2,7‐dichlorofluoresceindiacetate and Rh123 staining methods, respectively. The effect of d‐carvone against the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway was studied through immunoblotting. Then, we found that it effectively inhibited the proliferation of cell, and the induction of cell apoptosis was scrutinized by dual, 4’,6‐diamidino‐2‐phenylindole, and also propidium iodide staining methods. We also explored the fundamental molecular signaling mechanism of the d‐carvone and our data depicts that d‐carvone induced apoptosis cell death by mitochondrial reactive oxygen species production and downregulation of the and JAK and STAT3 signaling molecules. These overall findings support that the d‐carvone inhibits the JAK/STAT3 signaling pathway and induces cell death in the gastric cancer AGS cells.
Objective
The investigation of the effect of carvone (a natural monoterpene) on liver damage caused by chronic immobilisation.
Methods
Male Wistar rats were divided into four groups: control, carvone, stress, and stress-carvone. To induce stress, rats were placed in a restrainer (6 h/21 day) and carvone was treated by gavage at a dose of 20 mg/kg.
Results
Alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase activities were significantly increased in sera of immobilised rats. Chronic immobilisation also increased malondialdehyde levels and decreased reduced glutathione content, as well as increased TNF-α, IL-1β, IL-6, and NF-κB mRNA expression and also led to the infiltration of inflammatory cells in the liver parenchyma. Carvone’s 21-day treatment prevented all of these changes in immobilised rats.
Conclusion
It is concluded that carvone has effectively prevented chronic immobilisation-induced liver injury, most probably through its antioxidant and anti-inflammatory capabilities.
In this study, the chemical composition and antimicrobial activity of the essential oil (EO) extracted from leaves of the Moroccan endemic plant Argania spinosa were investigated for the first time, to the best of our knowledge. In addition, the EO antimicrobial activity was evaluated in combination with two known antibiotics (ciprofloxacin and fluconazole), in order to ascertain possible synergistic effects. The chemical composition analyzed by GC/MS showed that A. spinosa EO was characterised by the abundance of geranyl acetate (19.18%), methyleugenol (10.98%), linalyl acetate (10.59%) and eucalyptol (8.49%), and monoterpene hydrocarbons was the major class. EO showed an antimicrobial potential against all tested microorganisms. The highest activity was recorded against Gram positive bacteria and yeasts with MICs ranging from 7.75 to 15.5 mg/mL and from 3.88 to 7.75 mg/mL, respectively. The Gram negative bacteria were the most resistant with MICs of 31 mg/mL. The mixture of EO at sub-inhibitory concentrations with conventional drugs exhibited a significant decrease in their individual MICs from 4 to 32 fold. The highest level of synergy was observed for ciprofloxacin against Staphylococcus aureus, Bacillus subtilis and Escherichia coli. Despite the antimicrobial activity of A. spinosa EO is weak, the results of the current study suggest a potential synergy between EO and antibiotics in the goal to modulate drug resistance.
Artemisia species are aromatic herbs used as food and/or ethnomedicine worldwide; however, the use of these plants is often impeded by misidentification. Here, molecular and chemotaxonomic approaches were combined to assist in the morphology-based authentication of Artemisia species, and Artemisia indica and Artemisia argyi were identified. The plant extracts and compounds obtained from these species, 1,8-cineole, carveol, α-elemene, α-farnesene, methyl linolenate, diisooctyl phthalate inhibited the growth of food-borne harmful bacteria. Mechanistic studies showed that the extract and active compounds of A. indica killed Gram-negative and -positive bacteria via destruction of the bacterial membrane. Finally, in vivo data demonstrated that A. indica protected against bacterial infection in mice as evidenced by survival rate, bacterial load in organs, gut pathology, diarrhea, body weight, food consumption, stool weight, and pathology score. A. indica and its active compounds have potential for use as food supplements for food-borne bacterial diseases and thus improve human health.
Mint flavorings are widely used in confections, beverages, and dairy products. For the first time, mint flavoring composition of mint candies and food supplements (n = 45), originating from 16 countries, as well as their antibacterial properties, was analyzed. The flavorings were isolated by Marcussonʼs type micro-apparatus and analyzed by GC-MS. The total content of the mint flavoring hydrodistilled extracts was in the range of 0.01 – 0.9%. The most abundant compounds identified in the extracts were limonene, 1,8-cineole, menthone, menthofuran, isomenthone, menthol and its isomers, menthyl acetate. The antimicrobial activity of 13 reference substances and 10 selected mint flavoring hydrodistilled extracts was tested on Escherichia coli and Staphylococcus aureus by broth dilution method. Linalool acetate and (−)-carvone, as most active against both bacteria, had the lowest MIC90 values. (+)-Menthyl acetate, (−)-menthyl acetate, and limonene showed no antimicrobial activity. Three of the tested extracts had antimicrobial activity against E. coli and 8 extracts against S. aureus. Their summary antimicrobial activity was not always in concordance with the activities of respective reference substances.
Terpenoids, one of the major components of essential oils, are known to exert potent antifungal activity against yeast Saccharomyces cerevisiae. They have been the subject of a considerable number of investigations that uncovered extensive pharmacological properties, including antifungal and antibacterial effects. However, their mechanism of action remains elusive. In order to use terpenoids as the antimicrobial and antifungal agents in food preservation in a rational way, a good knowledge of their mode of action is required. We hypothesized that the cellular membrane is the main target site for the antifungal agents, and that structural properties of these agents are key to penetrate and act upon phospholipid bilayers. In this study, we thus aimed to study the effect of terpenoids on the cell membrane integrity, with the focus on both their structural properties, such as the presence of aromatic ring or hydroxyl group; and their hydrophobicity, as a consequence of these structural features. We first uncovered the antifungal properties of phenolic terpenoids thymol, carvacrol and eugenol, cyclic terpenes limonene, carveol, and α-pinene, in addition to the closely related compounds of different chemical structures. We then examined the cell membrane deterioration upon the addition of these reagents. Our results demonstrate that the presence of a phenolic –OH moiety is crucial, and hydrophobicity gained by the aromatic ring structure contributes to the ability of penetration and damaging yeast plasma membrane to achieve high antifungal activity.
Screening the biological activities of plant secondary metabolites on economic pests can lead to discovery new ecofriendly biopesticides. The aim of this work was to evaluate the antifeedant, growth inhibitory and toxic activities of seven monoterpenes, two phenylpropenes and two sesquiterpenes on 2nd larval instar of Spodoptera littoralis. The tested compounds induced a significant antifeedant effect at various concentrations (500, 1000 and 2000 mg/kg), particularly after 6 and 9 days of exposure. Among the tested compounds, trans-cinnamaldehyde, α-terpinene, (−)-citronellal and 1,8-cineole were the most potent antifeedants after the three exposure periods. In general the tested compounds showed remarkable antifeedant activity after 9 days of exposure as their antifeedant indices ranged between 44.0 and 80.1%. On the other hand, the tested compounds drastically inhibited the growth of S. littoralis larvae at the tested concentrations. The larval growth inhibition ranged between 21.4 and 100% with cuminaldehyde, 1,8-cineole and eugenol being the most potent growth inhibitors. Some of the tested compounds caused significantly higher antifeedant and growth inhibitory effects than a reference insecticide, pyriproxifen. In general, the tested compounds showed higher growth inhibition than antifeedant effect. The tested compound also induced S. littoralis larval morality which improved with increasing exposure time and concentration. Cuminaldehyde, 1,8-cineole and (−)-carvone showed highest toxicity with 100.0, 97.0 and 77.0% mortality, respectively, at 2000 mg/kg after 9 days of exposure. Biochemical studies revealed that trans-cinnamaldehyde (IC50 = 0.03 mM), farnesol (IC50 = 0.04 mM) and eugenol (IC50 = 0.06 mM) are potent α-amylase inhibitors. These three compounds also caused significant inhibition of total proteases activity. This is the first report on antifeedant, growth inhibitory and insecticidal activities of the tested compounds on S. littoralis. Moreover, the strong bioactivity reported in this study indicated that these compounds have a potential to be used as bioinsecticides.
In this study, an inexpensive, high yielding, and environmentally benign bifunctional acid-base catalyst is prepared using a simple low-temperature hydrothermal carbonization method from a fishery bio-waste, chitosan as a carbon source and sulfuric acid, as –SO3H source. The successful formation of –SO3H group grafted carbon was confirmed by various physiochemical characterization methods such as powder XRD, FTIR, RAMAN, FESEM, EDAX, HRTEM, and XPS. Under the optimized reaction conditions, the bio-derived sulfonated hydrothermal carbon catalyst showed excellent performance for the isomerization of α-pinene oxide to trans-carveol (85% yield) at 160 °C in 1.5 h. The product selectivity was influenced mainly by the type of solvent used for the isomerization. No leaching of the sulfonated groups was observed even after five cycles without any significant loss in conversion and selectivity.
With the purpose of searching for biological substances for controlling aflatoxins production in foodstuffs, we assessed the antifungal and antiaflatoxigenic activities of two essential oils (EOs) extracted from Carum carvi L., Coriandrum sativum L. seed and their major terpene component against Aspergillus flavus. The chemical profiles of Carum carvi, and Coriandrum sativum EOs were identified through Gas chromatography mass spectrometry analysis where carvone and linalool were respectively, recorded as the major terpene compound (78.85 and 72.34%). The effects of the EOs (0.1–0.7% (v/v)) and terpenes (100–2000 μg/mL) on the hyphal extension and aflatoxin B1 (AFB1) synthesis of A. flavus were tested by contact assay in Yeast Extract Sucrose medium. Carum carvi EO displayed a higher antimicrobial activity against A. favus than Coriandrum sativum EO with a minimum inhibitory concentration of about 0.4 and 0.7%, respectively. In the presence of 0.3% of EOs, 73.3 and 99.6% inhibition of AFB1 production was recorded, respectively, with Coriandrum sativm and Carum carvi. The antifungal and antiaflatoxigenic effects of carvone were also more significant than those of linalool (p < 0.05) with respectively, 64 and 16% of growth rate inhibition and 77.9 and 0.1% of AFB1 synthesis decrease recorded at 1000 μg/mL. Hence, the antifungal and antiaflatoxigenic activities of the two tested EOs were similar to their main terpene component. In conclusion, seed essential oils proved to be apotential natural source of antifungal and aflatoxin inhibition agent against Aspergillus flavus.
This study aims to evaluate the antifungal activity of Mentha spicata L. and Mentha pulegium L. from Sardinia and to assess their efficacy on virulence factors for Candida albicans, particularly on the inhibition of the germ tube formation. The major compounds of the essential oils were carvone (62.9%) for M. spicata and pulegone (86.2%) for M. pulegium. The essential oil from M. spicata showed a more preeminent effect against Cryptococcus neoformans and the dermatophytes Trichophyton rubrum and T. verrucosum (0.32 μL/mL). Both oils were very effective in inhibiting C. albicans germ tube formation, at doses well below their MIC (0.16 μL/mL).
Ethnopharmacological relevance
Aloysia polystachya (Griseb.) Moldenke (Verbenaceae) is a plant traditionally used as medicine for anxiety symptoms. This activity was confirmed in preclinical studies. However, its efficacy was never studied in human clinical trials.
Aim of the study
We aimed to test the hypothesis that the herbal medicine of A. polystachya is superior to placebo for the treatment of anxiety-related symptoms in adults after 8 weeks.
Patients and methods
This was a randomized, double-blind, placebo-controlled, phase-2 clinical trial. Fifty-four adults with self-reported anxiety symptoms were randomly allocated to receive either capsules containing A. polystachya powdered leaves (300 mg, twice a day) or placebo (maltodextrin), for 8 weeks. The intensity of anxiety symptoms was assessed by the Hamilton Anxiety Ranking Scale (HAM-A) at baseline and after 2, 4 and 8 weeks. All analyses were adjusted for physical activity (assessed by the International Physical Activity Questionnaire [IPAQ], short version) and gender.
Results
We confirmed the presence of acteoside (chromatographic analysis) and carvone and limonene (gas chromatography) as major constituents in our plant material. Only patients that received A. polystachya experienced a significant decrease in their HAM-A scores, with none or mild side-effects.
Conclusion
Administration of powdered leaves of A. polystachya, rich in acteoside, carvone and limonene, to adults with anxiety symptoms was significantly superior to placebo in decreasing HAM-A scores after 8 weeks. This finding confirms the ethnopharmacological use of this plant for anxiety symptoms.
Olfactory receptors are primarily expressed in nasal olfactory epithelium, but these receptors are also ectopically expressed in diverse tissues. In this study, we investigated the biological functions of Olfr43, a mouse homolog of human OR1A1, in cultured hepatocytes and mice to assess its functionality in lipid metabolism. Olfr43 was expressed in mouse hepatocytes, and Olfr43 activation by a known ligand, (−)-carvone, stimulated cAMP response element-binding protein (CREB) activity. In ligand-receptor binding studies using site-directed mutagenesis, (−)-carvone binding required two residues, M257 and Y258, in Olfr43. In the mouse study, oral administration of (−)-carvone for 5 weeks in high-fat diet-fed mice improved energy metabolism, including reductions in hepatic steatosis and adiposity, and improved glucose and insulin tolerance. In mouse livers and cultured mouse hepatocytes, Olfr43 activation simulated the CREB-hairy and enhancer of split 1 (HES1)-peroxisome proliferator-activated receptor (PPAR)-γ signaling axis, leading to a reduction in hepatic triglyceride accumulation in the mouse liver. Thus, long-term administration of (−)-carvone reduces hepatic steatosis. The knockdown of Olfr43 gene expression in cultured hepatocytes negated these effects of (−)-carvone. In conclusion, an ectopic olfactory receptor, hepatic Olfr43, regulates energy metabolism via the CREB-HES1-PPARγ signaling axis.