(
) is a herbaceous plant, cultivated worldwide and known for its biological benefits. The aim of this study is the investigation of the chemical composition as well as the determination of the ...biological potential of different grape stem extracts obtained by maceration and accelerated solvent extraction (ASE). The HPLC analysis of the tested extracts led to the identification of 28 compounds of which 17 were identified for the first time in grape plants, in addition to seven revealed in the stem part for the first time. Twenty-nine volatile molecules have been detected by GC-MS in the grape stem part; among them seven were identified for the first time in the grape plant. For the biological analysis, the ethyl acetate extract (EtOAc) obtained by maceration showed a significant potential regarding antioxidant activity (IC
= 42.5 µg/mL), anti-Alzheimer (IC
= 14.1 µg/mL), antidiabetic (IC
= 13.4 µg/mL), cytotoxic with HCT-116 (IC
= 12.5 µg/mL), and anti-inflammatory (IC
= 26.6 µg/mL) activities, as well as showing the highest polyphenol content (207.9 mg GAE/g DW).
Despite the numerous beneficial properties and uses of chitosan in agriculture, the molecular mechanisms behind its elicitation potential are still unclear. This study aimed at understanding the ...effect of chitosan application in the levels of phenolic compounds of
L. red grapes berry skin (cv. Tinto Cão) during veraison. Grapevines were treated with chitosan (0.01% in 0.01% acetic acid) while control grapevines were sprayed with 0.01% acetic acid. Results showed that several monomeric anthocyanins increased significantly in berry skins after treatment with chitosan. Additionally, Catechin, Rutin and Querecetin-3-
-galactoside were also recorded in higher amount upon chitosan treatment. Besides modulating the phenolic content, chitosan treatment also induced modifications in several target genes encoding key enzymes and transporters involved in secondary metabolic pathways. For instance, the genes
,
,
,
,
,
,
,
were upregulated in leaves and berry skins at veraison cessation in response to chitosan treatment. Overall, the results demonstrated that chitosan has a stimulatory effect on the accumulation of phenolic compounds, including anthocyanins, mediated by modifications in the transcription of key genes involved in their biosynthesis and transport in grape berries.
Background: Vitis vinifera is known for its antimicrobial activity; however, the hepatoprotective activity of aqueous extracts of aerial parts has also been reported, but the nephroprotective and ...hepatoprotective activity of ethanolic extracts have not yet been evaluated. Objective: To evaluate Vitis vinifera's hepatoprotective and nephroprotective activities against CCl4-induced toxicity in rats. Methods: Two doses of ethanolic extract of Vitis vinifera (100 and 200 mg/kg/day) were evaluated and compared with silymarin 100 mg/kg. Biochemical blood parameters like aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), Gamma-glutamyltranspeptidase (GGT), bilirubin, urea, uric acid, total protein and creatinine, and histopathologic changes of liver and kidney were studied and evaluated. Results: Vitis vinifera reduced the elevated blood levels of ALT, AST, ALP, urea, and creatinine, with the ethanol extract to 200 mg/kg/day being more effective. The histopathologic evaluation suggested that Vitis vinifera decreased hepatic and renal necrosis induced by CCl4. The more significant dose resulted in reductions in AST, ALT, GGT, ALP, and bilirubin of 54, 27, 56, 36, and 17%, respectively. Ethanolic extract 200 mg/kg/day also shows a reduction in elevated levels of Creatinine, Urea, Uric Acid, and Total Protein by 61%, 58%, 29%, and 9%, respectively. Conclusion: Hepatoprotective and nephroprotective activities of ethanol extract of Vitis vinifera were demonstrated, with ethanol extract to 200 mg/kg/day being the most effective. This presents scientific evidence for using medicinal plants such as Vitis vinifera in managing liver and kidney disorders.
In plants, carotenoids serve as the precursors to C13-norisoprenoids, a group of apocarotenoid compounds with diverse biological functions. Enzymatic cleavage of carotenoids catalysed by members of ...the carotenoid cleavage dioxygenase (CCD) family has been shown to produce a number of industrially important volatile flavour and aroma apocarotenoids including β-ionone, geranylacetone, pseudoionone, α-ionone and 3-hydroxy-β-ionone in a range of plant species. Apocarotenoids contribute to the floral and fruity attributes of many wine cultivars and are thereby, at least partly, responsible for the "varietal character". Despite their importance in grapes and wine; carotenoid cleavage activity has only been described for VvCCD1 and the mechanism(s) and regulation of carotenoid catabolism remains largely unknown.
Three grapevine-derived CCD-encoding genes have been isolated and shown to be functional with unique substrate cleavage capacities. Our results demonstrate that the VvCCD4a and VvCCD4b catalyse the cleavage of both linear and cyclic carotenoid substrates. The expression of VvCCD1, VvCCD4a and VvCCD4b was detected in leaf, flower and throughout berry development. VvCCD1 expression was constitutive, whereas VvCCD4a expression was predominant in leaves and VvCCD4b in berries. A transgenic population with a 12-fold range of VvCCD1 expression exhibited a lack of correlation between VvCCD1 expression and carotenoid substrates and/or apocarotenoid products in leaves, providing proof that the in planta function(s) of VvCCD1 in photosynthetically active tissue is distinct from the in vitro activities demonstrated. The isolation and functional characterisation of VvCCD4a and VvCCD4b identify two additional CCDs that are functional in grapevine.
Taken together, our results indicate that the three CCDs are under various levels of control that include gene expression (spatial and temporal), substrate specificity and compartmentalisation that act individually and/or co-ordinately to maintain carotenoid and volatile apocarotenoid levels in plants. Altering the expression of VvCCD1 in a transgenic grapevine population illustrated the divergence between the in vitro enzyme activity and the in planta activity of this enzyme, thereby contributing to the efforts to understand how enzymatic degradation of carotenoids involved in photosynthesis occurs. The identification and functional characterisation of VvCCD4a and VvCCD4b suggest that these enzymes are primarily responsible for catalysing the cleavage of plastidial carotenoids.
The widespread use of pesticides in agriculture remains a matter of major concern, prompting a critical need for alternative and sustainable practices. To address this, the use of lipid-derived ...molecules as elicitors to induce defence responses in grapevine plants was accessed. A Plasmopara viticola fatty acid (FA), eicosapentaenoic acid (EPA) naturally present in oomycetes, but absent in plants, was applied by foliar spraying to the leaves of the susceptible grapevine cultivar (Vitis vinifera cv. Trincadeira), while a host lipid derived phytohormone, jasmonic acid (JA) was used as a molecule known to trigger host defence. Their potential as defence triggers was assessed by analysing the expression of a set of genes related to grapevine defence and evaluating the FA modulation upon elicitation. JA prompted grapevine immunity, altering lipid metabolism and up-regulating the expression of several defence genes. EPA also induced a myriad of responses to the levels typically observed in tolerant plants. Its application activated the transcription of defence gene's regulators, pathogen-related genes and genes involved in phytoalexins biosynthesis. Moreover, EPA application resulted in the alteration of the leaf FA profile, likely by impacting biosynthetic, unsaturation and turnover processes. Although both molecules were able to trigger grapevine defence mechanisms, EPA induced a more robust and prolonged response. This finding establishes EPA as a promising elicitor for an effectively managing grapevine downy mildew diseases.
•Lipid-derived molecules offer a sustainable solution for managing grapevine diseases.•Jasmonic acid, a plant phytohormone, enhances grapevine immunity by modulating lipid metabolism and activating defence genes.•EPA, an oomycete-derived FA, induces defence mechanisms in a susceptible grapevine cultivar, resembling responses presented in tolerant grapevines.•Eicosapentaenoic acid elicits the up-regulation of defence genes, lipid signalling, and secondary metabolism.•The application of eicosapentaenoic acid elicits a stronger and longer-lasting response compared with jasmonic acid.
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