Antioxidative and macrophage phagocytic activities and functional component analyses of selected Korean chestunut (Castanea crenata S. et Z.) cultivars.

摘要

Antioxidative and macrophage phagocytic activities and contents of functional component in selected cultivars of Korean chestnuts (Dantaek, Daebo, Okkwang, Seokchu, Byunggo) were evaluated. Coumarin, gallic acid and catechin in inner skin and whole kernel of selected Korean chestnuts were detected by HPLC. The predominant functional components in inner skin of chestnut were catechin, followed by gallic acid and coumarin. However, the whole kernel had only gallic acid. Therefore the antioxidant properties of gallic acid and catechin were evaluated through DPPH radical-scavenging activity and SOD like activity. Gallic acid and catechin at 6.0 mg/100 g exhibited 69.4% and 38.3% of scavenging activities on DPPH radical, respectively. DPPH radical-scavenging activity of gallic acid increased in a concn.-dependent manner. Gallic acid was found to possess higher DPPH radical-scavenging activity than an equivalent amount of catechin at all concn., whereas catechin was found to have higher SOD like activity than gallic acid. In addition, pre-incubation of macrophage with white kernel extract from Byunggo and yellow kernel extracts from Byunggo, Dantaek, Daebo and Okkwang, resulted in a significant increase of phagocytic activity compared with untreated cells. Yellow kernel extracts were found to have higher phagocytic activity than white kernel extracts. Byunggo had the highest phagocytic activity. Results suggest that the Korean chestnut may provide a natural source of antioxidants and may enhance immunological response.