Polyphenolic composition and antioxidative activity of apple flesh extracts

The polyphenolic composition and the antioxidative activity of an apple fle sh extract and its fractions toward linoleic acid peroxidation in micelles of sodium dodecyl sulfate in buffer solution was studied. 1. The main pheno lic compounds in fraction B extracted with ethylacetate from aqueous sample solution were chlorogenic acid, (+)-catechin, (-)-epicatechin, oligomeric procyanidins and phloridzin, and in fraction A, which remained in the aqueo us phase, polymeric procyanidin was predominant. 2. Catechins (monomeric fo rms) and procyanidins (oligomeric and polymeric forms), especially polymeri c procyanidin, were predominant polyphenolic compounds in apple flesh. 3. T he relationship between polyphenolic concentration and antioxidative activi ty of apple flesh extract was almost same as that of standard (-)-epicatech in solution. In comparison between fraction A and B, the antioxidative acti vity of fraction B was slightly superior to that of fraction A. 4. The free radical scavenging activity of dimeric and trimeric procyanidins measured with a diphenyl-p-picryl hydrazyl (DPPH) method was stronger than that of m onomeric catechins, the same as the result of antioxidative activity in the SDS micellar system. The antioxidative activity of the fraction including polymeric procyanidin was lesser than that of catechins or dimeric and trim eric procyanidins, whereas the DPPH radical scavenging activity of this fra ction was superior to catechins or dimeric and trimeric forms.