Antioxidant Effects of Phenolic Acids and Ginseng Extract in Aqueous System

The antioxidant effects of 700 ppm ginseng extract, 100ppm caffeic acid, ferulic acid, vanillic acid, or on the 1% linoleic acid aqueous buffer system was studied by measuring malondialdehyde (MDA) and headspace oxygen. The compounds showed antioxidant activities in the following order: $caffeic\;acid{\geq}ferulic\;acid\;>\;{\alpha}-tocopherol$>ginseng extract>vanillic acid, with the oxidation inhibition ratio of 63.5, 62.9, 52.3, 51.2 and 5.6% of the control according to MDA results. The mixture of 100 ppm caffeic acid, 100 ppm and 700 ppm ginseng extract had a high oxidation inhibition ratio of 91.2%. Headspace oxygen results had a similar trend with the MDA results. Headspace oxygen results showed that the antioxidant activities were in order of ferulic acid>caffeic acid>>ginseng extract>vanillic acid and headspace oxygen contents were 18.56, 17.78, 17.17, 16.65 and 15.95%, respectively.