An investigation on polyphenol composition and content in skin of grape (Vitis vinifera L. cv. Hutai Number8) fruit during ripening by UHPLC-MS2 technology combined with multivariate statistical analysis was written by Du, Yan;Li, Xingyan;Xiong, Xiaolin;Cai, Xinyu;Ren, Xueyan;Kong, Qingjun. And the article was included in Food Bioscience in 2021.Recommanded Product: (2S,3R,4S,5S,6R)-2-(3-Hydroxy-5-((E)-4-hydroxystyryl)phenoxy)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol The following contents are mentioned in the article:
Polyphenols, a class of biol. active substances related to grapes quality, differ with maturity. This study aimed to evaluate polyphenol composition, content and antioxidant capacity of skin polyphenol extracts in Hutai Number 8 grape (Vitis vinifera L.) at five key ripening stages: full-green (FG), red-appeared (RA), half-red (HR), full-red (FR) and purple-black (PB), and to identify the polyphenolic compounds that had a potential to be markers for distinguishing the ripening stages. Grape skin extract at each ripening stage was studied for their total phenolic content (TPC), total flavonoid content (TFC) and the antioxidant capacity. Results showed a significant difference in accumulation of polyphenols at five stages. A trend towards an increase in TPC, TFC, and antioxidant capacity was observed during ripening. Then, this study profiled the polyphenolic compounds of grape skin at each ripening stage by UHPLC-ESI-qTOF-MS2 and UHPLC-QQQ-MS2. Results revealed that a total of 18 polyphenolic compounds were identified. Polyphenols were quantified according to phenolic class. And catechin was the major flavanol in skin, which was observed the highest content at the HR stage. Furthermore, quercetin-3-O-glucoside, 1-O-vanilloyl-β-D-glucose and resveratrol-3-O-glucoside were resp. considered as the representative phenolic acid and stilbene, all of which were detected the highest at the PB stage. Moreover, polyphenolic compounds that had a potential to be markers for distinguishing the ripening stages of Hutai Number8 grape were identified through orthogonal partial least squares discriminant anal. (OPLS-DA). Results indicated that catechin, epicatechin, quercetin-3-O-glucoside, myricetin, isorhamnetin-3-O-hexose and resveratrol-3-O-glucoside were the vital markers. The study provides a reference for differentiating grapes at different ripening stages based on polyphenols. This study involved multiple reactions and reactants, such as (2S,3R,4S,5S,6R)-2-(3-Hydroxy-5-((E)-4-hydroxystyryl)phenoxy)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol (cas: 27208-80-6Recommanded Product: (2S,3R,4S,5S,6R)-2-(3-Hydroxy-5-((E)-4-hydroxystyryl)phenoxy)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol).
(2S,3R,4S,5S,6R)-2-(3-Hydroxy-5-((E)-4-hydroxystyryl)phenoxy)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol (cas: 27208-80-6) belongs to alcohols. The oxygen atom of the strongly polarized O―H bond of an alcohol pulls electron density away from the hydrogen atom. This polarized hydrogen, which bears a partial positive charge, can form a hydrogen bond with a pair of nonbonding electrons on another oxygen atom. The most common reactions of alcohols can be classified as oxidation, dehydration, substitution, esterification, and reactions of alkoxides.Recommanded Product: (2S,3R,4S,5S,6R)-2-(3-Hydroxy-5-((E)-4-hydroxystyryl)phenoxy)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol
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