SEMIPREPARATIVE CHROMATOGRAPHIC PROCEDURE FOR THE ISOLATION OF DIMERIC AND TRIMERIC PROANTHOCYANIDINS FROM BARLEY

Citation
I. Mcmurrough et al., SEMIPREPARATIVE CHROMATOGRAPHIC PROCEDURE FOR THE ISOLATION OF DIMERIC AND TRIMERIC PROANTHOCYANIDINS FROM BARLEY, Journal of agricultural and food chemistry, 44(7), 1996, pp. 1731-1735
Citations number
25
Categorie Soggetti
Food Science & Tenology",Agriculture,"Chemistry Applied
ISSN journal
00218561
Volume
44
Issue
7
Year of publication
1996
Pages
1731 - 1735
Database
ISI
SICI code
0021-8561(1996)44:7<1731:SCPFTI>2.0.ZU;2-1
Abstract
A semipreparative chromatographic method for the isolation of small am ounts (10-20 mu g) of dimeric and trimeric proanthocyanidins from barl ey is described. Concentrated extracts of barley were injected onto a high-performance gel filtration column (Superdex 75 HR), and were elut ed with methanol. This procedure resolved the dimeric proanthocyanidin s (prodelphinidin B3 and procyanidin B3), as well as the trimeric proc yanidin C2 and three other trimeric prodelphinidins. The separated fla vanoid peaks were collected and their contents were estimated by UV sp ectrophotometry, reaction with p-dimethylaminocinnamadehyde, and rever sed phase HPLC with electrochemical detection. This method produced pr oanthocyanidins in sufficient amounts to calibrate a system for direct injection chromatographic analysis of beers and barley extracts. The method described may be optimized for the isolation of dimeric proanth ocyanidins only, in which case the preparation can take as little as 3 h; alternatively, by extending the chromatographic separation to 9 h, the four major trimeric proanthocyanidins of barley can be recovered also in a chromatographically pure state.