ANTIOXIDATIVE EFFECT OF ISUBGOL IN MODEL AND IN LIPID SYSTEM

Eight separate solvent systems were used to determine which was most e ffective and rapid for extraction of antioxidants from seeds of isubgo l (Plantago ovata); methanolic extracts showed the highest antioxidati ve power. Effectiveness was tested in a model system of linoleic acid and in a lipid system of soybean oil stored at 32C and 60C and heated at 180C. The methanolic extracts of isubgol tested in emulsified linol eic acid showed no marked decrease in oxidation compared to the contro l, as measured by coupled oxidation with beta-carotene, conjugated die nes (CD) values, and TEA-test. The extracts in soybean oil did not pro duce significantly lower peroxide values, lower CD, or higher 18:2/16: 0 ratios than the control during storage and heating tests. Thus, isub gol is not a potential source of natural antioxidant.