Fig 5
Gallic acid metabolism in grape berry tissues along development. (A–C) Gallic acid and β-glucogallin in grape berry tissues (A), skin (B), pulp, and (C) seeds. White and grey bars correspond to GA and β-glucogallin, respectively. Data are expressed g–1 of fresh weight and represent the mean of three replicates ±SD. Samples corresponding to the green stage, véraison, and maturity were collected at 18, 52, and 99 d after flowering, respectively. (D) Galloylated flavan-3-ols in grape berry tissues. Galloylated flavan-3-ols have been quantified after depolymerization by phloroglucinolysis. Grey, white, and black bars correspond to skin, pulp, and seeds, respectively. Data are expressed g–1 of frozen powder and represent the mean of three replicates ±SD. (E) Galloylation rate (%G) of flavan-3-ols in grape berry tissues. Flavan-3-ols have been quantified after depolymerization by phloroglucinolysis. Grey, white, and black bars correspond to skin, pulp, and seeds, respectively. Data represent the mean of three replicates ±SD.
Source publication
In plants, the shikimate pathway provides aromatic amino acids that are used to generate numerous secondary metabolites, including
phenolic compounds. In this pathway, shikimate dehydrogenases (SDH) ‘classically’ catalyse the reversible dehydrogenation
of 3-dehydroshikimate to shikimate. The capacity of SDH to produce gallic acid from shikimate pat...
Contexts in source publication
Context 1
... could be involved in GA biosynthesis, thus indirectly affecting the galloylation rate of flavan-3-ols. Using the same screening approach, three grape- vine UDP-glucosyltransferases (VvgGTs) were also identi- fied. They are expressed in the early stages of grape berry development and could catalyse the biosynthesis of β-G, as demonstrated in vitro (Fig. 1, reaction 5) by Khater et al. (2012). Several studies suggest that Serine Carboxypeptidase- Like (SCPL) acyltransferase(s) could be involved in the fur- ther step of flavan-3-ol galloylation, using β-G (for a review see Bontpart et al., 2015;Fig. 1, reaction ...
Context 2
... content of galloylated flavan-3-ols and %G, GA and its glucose ester, β-G, was measured in skin, pulp, and seeds, at three development stages: green stage (18 daf), véraison (52 daf), and maturity (99 daf) (Fig. 5). At the same devel- opment stage, GA and β-G contents were always higher in seeds than in pulp and skin. The molar ratio β-G/GA was systematically lower or close to 1, except in immature seeds in which it was close to 2.4. In skin and pulp, the GA content was maximal during the green stage (~20 and 4 nmol g −1 FW, respectively, Fig. ...
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... (99 daf) (Fig. 5). At the same devel- opment stage, GA and β-G contents were always higher in seeds than in pulp and skin. The molar ratio β-G/GA was systematically lower or close to 1, except in immature seeds in which it was close to 2.4. In skin and pulp, the GA content was maximal during the green stage (~20 and 4 nmol g −1 FW, respectively, Fig. 5A, B). Therefore, GA is mainly synthesized Fig. 2. Neighbor-Joining tree of selected dehydroquinate dehydratase/shikimate dehydrogenases from dicots. This phylogenetic tree was constructed from the four VvSDHs sequenced in this study and the 28 sequences available on public databases (NCBI and Phytozome) using MEGA6 software. Bootstrap ...
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... III: EgSDH3 (Eucgr.H04427.1), FvSDH1 (XP_004302480), VvSDH3 (KU163042), CasSDH2 (AJA40947); Group IV: EgSDH2 (Eucgr.H04428.1), VvSDH4 (KU163043), Poptr5 (Potri.013G029800), FvSDH2 (XP_004302479), DkSDH (BAI40147), CasSDH3 (AJA40948); Group V: Poptr4 (Potri.014G135500), EgSDH1 (Eucgr.H01214.1), CsSDH2 (orange1.1g010101m), SlSDH3 (XP_004242317 Fig. 5C) could be due to the release of galloyl moieties from galloylated flavan-3-ols, as their con- tent decreases from véraison in seeds (Fig. 5D) leading to a reduction of flavan-3-ols %G (Fig. ...
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... Poptr5 (Potri.013G029800), FvSDH2 (XP_004302479), DkSDH (BAI40147), CasSDH3 (AJA40948); Group V: Poptr4 (Potri.014G135500), EgSDH1 (Eucgr.H01214.1), CsSDH2 (orange1.1g010101m), SlSDH3 (XP_004242317 Fig. 5C) could be due to the release of galloyl moieties from galloylated flavan-3-ols, as their con- tent decreases from véraison in seeds (Fig. 5D) leading to a reduction of flavan-3-ols %G (Fig. ...
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... DkSDH (BAI40147), CasSDH3 (AJA40948); Group V: Poptr4 (Potri.014G135500), EgSDH1 (Eucgr.H01214.1), CsSDH2 (orange1.1g010101m), SlSDH3 (XP_004242317 Fig. 5C) could be due to the release of galloyl moieties from galloylated flavan-3-ols, as their con- tent decreases from véraison in seeds (Fig. 5D) leading to a reduction of flavan-3-ols %G (Fig. ...
Context 7
... expression level of VvSDH3 has been measured in control and transgenic lines, using VvEF1α as the reference gene ( Supplementary Fig. S5). ...
Citations
... While genes involved in the purpurogallin biosynthetic pathway were found across the green plants, one component, dehydroquinate dehydratase/shikimate dehydrogenase (DHQD/SD), was present at a high copy number (9) in A. nordenski€ oldii; greater than in any other green plant species (Fig. 3; Table S16). DHQD/SD catalyses the dehydration of dehydroquinate (DHQ) to dehydroshikimate (DHS) and the reduction of dehydroshikimate (DHS) to shikimate (Bontpart et al., 2016;Lynch, 2022), leading to the spontaneous synthesis of gallic acid. Phylogenetic analysis demonstrated that the expansion of this gene family was specific to A. nordenski€ oldii (Fig. 3c). ...
Contemporary glaciers are inhabited by streptophyte algae that balance photosynthesis and growth with tolerance of low temperature, desiccation and UV radiation. These same environmental challenges have been hypothesised as the driving force behind the evolution of land plants from streptophyte algal ancestors in the Cryogenian (720–635 million years ago).
We sequenced, assembled and analysed the metagenome‐assembled genome of the glacier alga Ancylonema nordenskiöldii to investigate its adaptations to life in ice, and whether this represents a vestige of Cryogenian exaptations.
Phylogenetic analysis confirms the placement of glacier algae within the sister lineage to land plants, Zygnematophyceae. The metagenome‐assembled genome is characterised by an expansion of genes involved in tolerance of high irradiance and UV light, while lineage‐specific diversification is linked to the novel screening pigmentation of glacier algae. We found no support for the hypothesis of a common genomic basis for adaptations to ice and to land in streptophytes. Comparative genomics revealed that the reductive morphological evolution in the ancestor of Zygnematophyceae was accompanied by reductive genome evolution.
This first genome‐scale data for glacier algae suggests an Ancylonema‐specific adaptation to the cryosphere, and sheds light on the genome evolution of land plants and Zygnematophyceae.
... The odorless white to pale yellow crystalline powder of gallic acid has a slightly sour taste and contains three hydroxyl (-OH) groups attached to a benzene ring. Its formation involves the enzyme shikimate dehydrogenase converting 3-dehydroshikimate to 3,5-didehydroshikimate [34,35]. Gallic acid is soluble in water, alcohol, and acetone but has limited solubility in non-polar solvents like ether and chloroform [36]. ...
The growing global population challenges the food industry to ensure it remains safe for consumption. Food waste caused by imbalances between production and handling creates significant economic, environmental, and social risks. However, packaging technology innovation has emerged as a powerful tool, offering a solution by extending shelf life and maintaining food product quality. Consumers' increasing interest in eco-friendly packaging has driven research into renewable materials and low-toxicity bioactive components. Gallic acid, a promising phenolic compound, holds potential for food preservation and sustainable packaging development. Its antibacterial and antifungal properties against resistant microbes and biofilm formation, its ability to prevent lipid and protein oxidation, and its potential as a color indicator for monitoring food freshness all contribute to food preservation. Its incorporation into edible polymers offers a strategy for innovative edible packaging. Depending on the dosage and material composition, loading gallic acid within the polymer matrix can improve packaging properties, including UV barrier, mechanical strength, and water vapor and oxygen permeability. This article reviews the potential of gallic acid for developing biodegradable, active, intelligent, and edible packaging. Future directions include evaluating gallic acid's toxicity, dispersion within the matrix, pro-oxidative activity, compatibility with biodegradable polymers (especially those derived from agricultural by-products), migration into food products, and stability under different environmental conditions. The sustainability perspective (environment, economic, and social) is also discussed.
... To gain more knowledge on the levels of GA, a precursor for HT biosynthesis (Muir et al. 2011;Bontpart et al. 2016;Habashi et al. 2019) and punicalagins in transgenic hairy roots of the 15 accessions and their respective untransformed control roots, we used HPLC (Fig. S4). A significant increase in GA concentrations was observed in the transgenic hairy roots of 13 out of the 15 accessions compared to their respective control roots (Fig. 3b). ...
Pomegranates (Punica granatum) are known for their high levels of health-beneficial compounds that belong to the hydrolyzable tannin (HT) and flavonoid families. However, a significant gap in our understanding exists of the biosynthetic and regulatory genes related to the accumulation of these compounds. To this end, the induction and transformation of hairy roots presents an exciting opportunity to decipher genetically the functions of candidate genes involved in the HT and flavonoid metabolism. This study aims at improving methods for rapid and abundant hairy root production from pomegranate explants by increasing seed germination rates and expediting the attainment of requisite biomass for multifaceted analyses. We found that treating seeds with sandpaper and concentrated sulfuric acid significantly enhanced their germination rates. Interestingly, no correlation between seed-coat texture and seed germination rate was observed among the 20 pomegranate accessions evaluated in this study. Notably, transferring hairy roots from agar plates to soil promoted rapid root biomass growth compared to maintaining them on agar plates. Root biomass as well as levels of gallic acid (a precursor for HT biosynthesis) and punicalagins (the major HTs in roots) across 15 pomegranate accessions were also analyzed. Three of these accessions exhibited higher seed germination percentages along with augmented biomass and elevated punicalagin levels. These pomegranate accessions emerge as promising germplasm for future genetic transformation and functional genomics studies.
... Supporting this, previous studies have shown that some plants have more than one DHQD/SDH enzyme involved in synthesizing gallic and quinic acids. This was reported in Nicotiana tabacum [47], Betula pubescens [58], Populus trichocarpa [59], Vitis vinifera [60], Camellia sinensis [61], and more recently, in aluminum-tolerant Eucalyptus camaldulensis [62]. These findings suggest that maize seedlings might suffer from an overflow mechanism in the pathway, leading to gallic acid accumulation. ...
The shikimate pathway is crucial for the biosynthesis of aromatic amino acids in plants and represents a promising target for developing new herbicides. This work aimed to identify inhibitors of shikimate dehydrogenase (SDH), a key enzyme of the shikimate pathway that catalyzes the conversion of 3-dehydroshikimate to shikimate. Virtual screening and molecular dynamic simulations were performed on the SDH active site of Arabidopsis thaliana (AtSDH), and 6-nitroquinazoline-2,4-diol (NQD) was identified as a potential inhibitor. In vitro assays showed that NQD decreased the activity of AtSDH by reducing Vmax while keeping KM unchanged, indicating non-competitive inhibition. In vivo, hydroponic experiments revealed that NQD reduced the root length of soybean and maize. Additionally, NQD increased the total protein content and certain amino acids. Soybean roots uptake NQD more efficiently than maize roots. Furthermore, NQD reduced shikimate accumulation in glyphosate-treated soybean roots, suggesting its potential to restrict the flow of metabolites along the shikimate pathway in soybean. The simultaneous treatment of maize seedlings with glyphosate and NQD accumulated gallic acid in the roots, indicating that NQD inhibits SDH in vivo. Overall, the data indicate that NQD inhibits SDH both in vitro and in vivo, providing valuable insights into the potential development of herbicides targeting SDH.
... Supporting this, previous studies have shown that some plants have more than one DHQD/SDH enzyme involved in synthesizing gallic and quinic acids. This was reported in Nicotiana tabacum [51], Betula pubescens [58], Populus trichocarpa [59], Vitis vinifera [60], Camellia sinensis [61], and more recently, in aluminum-tolerant Eucalyptus camaldulensis [62]. These findings suggest that maize seedlings might suffer from an overflow mechanism in the pathway, leading to gallic acid accumulation. ...
The shikimate pathway is crucial for the biosynthesis of aromatic amino acids in plants and represents a promising target for developing new herbicides. This work aimed to identify inhibitors of shikimate dehydrogenase (SDH), a key enzyme of the shikimate pathway that catalyzes the conversion of 3-dehydroshikimate to shikimate. Virtual screening and molecular docking were performed on the SDH active site of Arabidopsis thaliana (AtSDH), and 6-nitroquinazoline-2,4-diol (NQD) was identified as a potential inhibitor. In vitro assays showed that NQD decreased the activity of AtSDH by reducing Vmax while keeping KM unchanged, indicating noncompetitive inhibition. In vivo, hydroponic experiments revealed that NQD reduced the root length of soybean and maize. Additionally, NQD increased the total protein content and certain amino acids. Soybean roots uptake NQD more efficiently than maize roots. Furthermore, NQD reduced shikimate accumulation in glyphosate-treated soybean roots, suggesting its potential to restrict the flow of metabolites along the shikimate pathway in soybean. Simultaneous treatment of maize seedlings with glyphosate and NQD accumulated gallic acid in the roots, indicating that NQD inhibits SDH in vivo. Overall, the data indicate that NQD inhibits SDH both in vitro and in vivo, providing valuable insights into the potential development of herbicides targeting SDH.
... It is known that the shikimate pathway produces carbon frameworks for aromatic amino acid synthesis as well as various secondary metabolites further along the pathway (Bontpart et al., 2016). ...
... gives 5-enol pyruvyl shikimate-3-phosphate (EPSP). Finally, EPSP is transformed into chorismate in the presence of chorismate synthase and completes the shikimate pathway (Bontpart et al., 2016). ...
In the middle of an ever-changing landscape of diabetes care, precision medicine, and lifestyle therapies are becoming increasingly important. Dietary polyphenols are like hidden allies found in our everyday meals. These biomolecules, found commonly in fruits, vegetables, and various plant-based sources, hold revolutionary potential within their molecular structure in the way we approach diabetes and its intimidating consequences. There are currently numerous types of diabetes medications, but they are not appropriate for all patients due to limitations in dosages, side effects, drug resistance, a lack of efficacy, and ethnicity. Currently, there has been increased interest in practicing herbal remedies to manage diabetes and its related complications. This article aims to summarize the potential of dietary polyphenols as a foundation in the treatment of diabetes and its associated consequences. We found that most poly-phenols inhibit enzymes linked to diabetes. This review outlines the potential benefits of selected molecules, including kaempferol, catechins, rosmarinic acid, apigenin, chlorogenic acid, and caffeic acid, in managing diabetes mellitus as these compounds have exhibited promising results in in vitro, in vivo, in silico, and some preclinical trials study. This encompassing exploration reveals the multifaceted impact of polyphenols not only in mitigating diabetes but also in addressing associated conditions like inflammation, obesity, and even cancer. Their mechanisms involve antioxidant functions, immune modulation, and proinflammatory enzyme regulation. Furthermore, these molecules exhibit anti-tumor activities, influence cellular pathways, and activate AMPK pathways, offering a less toxic, cost-effective, and sustainable approach to addressing diabetes and its complications.
... Another significant phenolic acid in grapes is gallic acid (Fig. 2). It is formed from an intermediate compound in the upstream reactions of the shikimate pathway, thanks to the activity of a dehydroshikimate dehydrogenase (Bontpart et al. 2016). Gallic acid participates in several reactions, such as the galloylation of flavanols. ...
... Gallic acid biosynthesis has been studied since the 1960s [47]. The shikimate dehydrogenase enzyme dehydrogenates 3-dehydroshikimate to turn it into 3,5-didehydroshikimate, which is the most likely method for producing gallic acid ( Fig. 2) [48,49]. ...
GA (Gallic acid) belongs to the phenolic molecule that is naturally present in plants, and has an assortment of medicinal benefits on inflammation, obesity, cancer, the heart, neurological system, and the proliferation of cells. In more recent research, the anti-cancer effects via biological mechanisms such as angiogenesis, migration, metastasis, cell cycle arrest, and apoptosis have been demonstrated. Anti-cancer activities of gallic acid are affected through the biological methods which involve reluctance of tumor migration, inflammation, etc. Numerous degenerative diseases, namely blood-vascular, ageing, inflammatory contagion and malignancy are brought on owing to the free radical damage because of the excess amount of free radicals produced and accretion. We carried out a comprehensive examination of the literature employing the expression of gallic acid. To review the most current advancements and clinical investigations for the pharmacological effects of gallic acid, recognized research from various reputable organizations and sites including Scopus, ClinicalTrails.gov, Science Direct, and PubMed were analyzed. This review, which offers a succinct description of gallic acid, updates the contents of clinical research and patent data, it brings forth the elaborate attainment regarding the various abundant therapeutic efficacies along with the extraction methodology of the drug that is used to obtain it, including microwave-assisted extraction and maceration extraction, among others, as well as non-chromatographic and chromatographic techniques for its isolation and quantification. Antifungal, antiulcer, antiviral, anticancer, and antibacterial properties are just a few of the pharmacological effects of naturally occurring gallic acid.
... In turn, quinate is esterified with caffeoyl-CoA to produce chlorogenic acid (Marchiosi et al. 2020). Lastly, a DHQD/SDH that catalyzes gallate production from DHS has also been described in Juglans regia and V. vinifera (Muir et al. 2011;Bontpart et al. 2016). The gallate produced is used as a precursor in the synthesis of hydrolysable tannins, condensed tannins or galloylated catechins. ...
... In vine berries (V. vinifera), four SDH proteins (VvSDH) were identified: one with the so-called ''classic'' activity (VvSDH1), two related to gallic acid formation (VvSDH3 and VvSDH4), and another possibly related to quinic acid biosynthesis (Fig. 2h) (Bontpart et al. 2016). Similarly, four genes were identified for DHQD-SDH in Camellia sinensis: one facing the shikimate pathway (CsDQD/SDHa), two possibly involved in gallic acid biosynthesis (CsDQD/ SDHc and CsDQD/SDHd), and another (CsDQD/ SDHb) allegedly related to quinic acid biosynthesis (Huang et al. 2019). ...
Absent in animals and with only seven enzymatic reactions toward the synthesis of chorismate and aromatic amino acids, the shikimate pathway is a crucial target for developing antimicrobial agents and herbicides. Although this pathway has been extensively studied in microorganisms related to human health, it reveals complexities in plants, as it takes part in primary and secondary metabolism. Obtaining enzyme inhibitors is essential to circumvent the occurrence of weeds resistant to commercially available herbicides and to help control human diseases, which has challenged researchers to search for new molecules and investigate their modes of action. By applying bioinformatics tools, thousands of enzyme inhibitors of this metabolic pathway can be prospected at a low cost and in a short time. Here, we revisit how the enzymes of the shikimate pathway have been characterized and update the status of their inhibitors in microorganisms and plants. This overview can be constructive in searching for enzyme inhibitors in the academic, human health, and agro-industrial fields.
... Biosynthesis of gallic acid is formed from 3-dehydroshikimate in the presence of shikimate dehydrogenase enzyme to produce 3,5-didehydroshikimate. Further, the 3,5-didehydroshikimate compound rearranges the structure spontaneously to form gallic acid [55]. In the ultrasonication method, Cystophora sp. ...
Seaweeds, serving as valuable natural sources of phenolic compounds (PCs), offer various health benefits like antioxidant, anti‐inflammatory properties, and potential anticancer effects. The efficient extraction of PCs from seaweed is essential to harness their further applications. This study compares the effectiveness of different solvents (ethanol, methanol, water, acetone, and ethyl acetate) for extracting PCs from four seaweed species: Ascophyllum sp., Fucus sp., Ecklonia sp., and Sargassum sp. Among them, the ethanol extract of Sargassum sp. had the highest content of total phenolics (25.33 ± 1.45 mg GAE/g) and demonstrated potent scavenging activity against the 2,2‐diphenyl‐1‐picrylhydrazyl radical (33.65 ± 0.03 mg TE/g) and phosphomolybdate reduction (52.98 ± 0.47 mg TE/g). Ecklonia sp. had the highest content of total flavonoids (0.40 ± 0.02 mg QE/g) in its methanol extract, whereas its ethyl acetate extract contained the highest content of total condensed tannins (8.09 ± 0.12 mg CE/g). Fucus sp. demonstrated relatively strong antioxidant activity, with methanolic extracts exhibiting a scavenging ability against 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radical (54.41 ± 0.24 mg TE/g) and water extracts showing ferric‐reducing antioxidant power of 36.24 ± 0.06 mg TE/g. Likewise, liquid chromatography–mass spectrometry identified 61 individual PCs, including 17 phenolic acids, 32 flavonoids, and 12 other polyphenols. Ecklonia sp., particularly in the ethanol extract, exhibited the most diverse composition. These findings underscore the importance of selecting appropriate solvents based on the specific seaweed species and desired compounds, further providing valuable guidance in the pharmaceutical, nutraceutical, and cosmetic industries.
Practical Application
The PCs, which are secondary metabolites present in terrestrial plants and marine organisms, have garnered considerable attention due to their potential health advantages and diverse biological effects. Using various organic/inorganic solvents during the extraction process makes it possible to selectively isolate different types of PCs from seaweed species. The distinct polarity and solubility properties of each solvent enable the extraction of specific compounds, facilitating a comprehensive assessment of the phenolic composition found in the seaweed samples and guiding industrial production.
