GLUCOSYLATED FLAVONOIDS AND OTHER PHENOLIC COMPOUNDS FROM SORGHUM

Article abstract of DOI:10.1016/S0031-9422(00)81304-7

The principal tannin constituents of sorghum are proanthocyanidins or condensed tannins.Analysis of the methanolic extract of a Hungarian sorghum (szegedi toerpe) containing 6percent catechin equivalents of tannins resulted in the separation and purification of 4 procyanidins having the basic formula epicatechin-(epicatechin)_n-catechin and one procyanidin trimer corresponding to epicatechin-catechin-epicatechin.Apart from these procyanidins, the monomeric flavonoids eriodictyol 5-glucoside and (+)-taxifolin 7 glucoside together with their aglycones eriodictyol and taxifolin were found.Glucosylated dimeric and trimeric flavanoids with eriodictyol or eriodictyol 5-glucoside as the lower unit were also identified with the help of negative ion FABMS.Polymeric flavonoids formed between a chalcone and a flavonoid, as yet not identified, are also present in the grain. Key Word Index - Sorghum; Gramineae; flavanoids; glycosides; new oligomer glucosides; procyanidins; chalchone identification.