IDENTIFICATION AND FUNCTION OF ANTIOXIDANTS FROM OAT GREATS AND HULLS

Antioxidant components of methanolic Extracts of greats and hulls from Ogle oats were identified and quantified by using gas chromatography- mass spectrometry (CC-MS) and gas chromatography after N,O-bis(trimeth ylsilyl)acetamide derivatization. Ferulic. p-coumaric, vanillic, p-hyd roxybenzoic, 4-hydroxyphenylacetic acids and vanillin and catechol wer e quantified in great and hull extracts. Additionally, caffeic acid in great extracts, and o-coumaric, sinapic and salicylic acids in hull e xtracts were quantified. Extracts from greats and hulls at levels of 0 .05, 0.1, 0.2, and 0.3% w/w, based on total phenolic content, were add ed to soybean oil, and their antioxidant effectiveness was compared wi th that of 0.02% w/w tertiary butylhydroquinone (TBHQ) and a control i no additives) at 60 degrees C in the dark by measuring peroxide values . Antioxidant activities of both extract sources increased with increa sed concentration. During 20 d of storage, the great extract (0.3%) wa s not significantly different from TBHQ after day 16, and hull extract s (0.2 and 0.3%) were not significantly different from TBHQ on day 20. Oils containing pure phenolics at the same concentrations measured in the great and hull extracts oxidized more quickly than did oils conta ining the extracts.