Analysis of plant polyphenols by high performance liquid chromatography/mass spectrometry and protein binding
The high molecular weight plant polyphenols known as tannins have both positive and negative effects on human and animal health. Tannin constituents from natural sources have been implicated in astringency of wine, inhibition of carcinogenesis and control of diabetes. The main tannin constituents in white oak, black raspberry and tannic acid were analyzed with HPLC and mass spectrometry. Vescalagin, castalagin, grandinin and roburin E, four ellagitannins purified from the white oak were characterized with a preliminary radiolabeled protein-binding assay. Sanguiin H-10 and its precursors were identified as the main ellagitannins in black raspberry. A hexagalloyl constituent of tannic acid was identified as the active constituent likely to have insulin-mimetic activity. A simple method was devised to assess the protein binding capacities of plant polyphenols by immobilizing unfractionated plant extracts on filter paper disks, and reacting with radiolabeled BSA. Protein binding was proportional to the amount of immobilized extract.
School Location:USA - Ohio
Source Type:Master's Thesis
Keywords:hplc ms tannin polyphenols protein binding
Date of Publication:01/01/2004