Plant Phenolics

3-monoglucoside 3,5-diglucoside absorption Acad Academic Press acetic acid acylated aglycones alcohol alkaline antho anthocyanins apigenin aqueous aurones Bate-Smith benzene ring benzoic acids Biochem biosynthesis blue bond C.r. hebd caffeic acid carbon atom catechins CH CH CH OH CH3O chalcones Chem chemical chemistry chim chloride chromatogram cinnamic acids colour complex condensed tannins COOH coumarins cyanidin cyanins delphinidin derivatives diglucosides electrons eluted enzymes especially esters ethanol extraction flavanones flavones flavonoids flavonols formation gallic acid Geissman give glycosides grapes Harborne hydrogen hydrolysis hydroxyl group identification isoflavones J. B. Harborne Jurd kaempferol leucoanthocyanins lignin malvidin method methylated molecular molecule myricetin nature obtained OH group OH OH oxidation p-coumaric p-coumaric acid paper chromatography pelargonidin petunidin phenolic acids phenolic compounds phenolic constituents Phytochem pigments plant tissues polymerisation present properties quercetin R=OH reaction reagent Ribéreau-Gayon separation sodium solution solvent spectra structure studied substances sugar residue Swain Table tannins ultraviolet ОН