| Abstract: | Aqueous extracts of fresh and dehydrated lucerne were found to exhibit heat-stable antioxidant activity toward the autoxidation of linoleic acid, the lipoxidase-catalysed oxidation of linoleic acid and the lipoxidase-induced carotene oxidation. EDTA increased the antioxidant activity of lucerne extract in all three systems. Alone, EDTA inhibited linoleate autoxidation, but not lipoxidase-catalysed linoleate oxidation, and was only partly inhibitory toward lipoxidase-induced carotene oxidation. The presence of ferulic acid in the acid hydrolysate of lucerne extract could be demonstrated by both paper and gas chromatography. This acid, and the related coumaric and sinapic acids, were shown to inhibit lipoxidase activity. It is suggested that a ferulic acid derivative may play a rôle in the antioxidant effects observed with aqueous lucerne extracts. |
