DNA Protection and Antioxidant Potential of Chestnut Shell Extracts

Abstract

Castanea crenata is a species of chestnut originally native to South Korea and Japan. In this study, chestnut shell was investigated as a potential source of antioxidant compounds. Distilled water and ethanol extracts were prepared from chestnut shell and their antioxidant activities were investigated in vitro using different analytical methods, including 2,2-diphenyl-1-picrylhydrazyl, 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid), hydroxyl, superoxide radical and nitrite scavenging, reducing (Fe3+ to Fe2+) power, linoleic acid oxidation inhibition and free radical-induced DNA damage prevention activity. The extracts showed excellent radical-scavenging activities and prevented free radical-induced DNA damage. The antioxidant activity was highly correlated with the observed phenolic and flavonoid contents. Our results suggest that the extracts derived from chestnut shells could be a potent source of natural antioxidants. Practical Applications Chestnuts (Castanea crenata) are widely available in Korea. The chestnut inner shell has been used as a cosmetic material for a long time in Korea, and previous research has demonstrated that chestnut fruits and leaves contain phenolic compounds. However, little is known about the potential uses of chestnut shell. Chestnut has been sold as an anti-wrinkle and anti-aging compound when mixed with honey, and previous research on the chestnut inner shell has suggested that this material inhibited the biosynthesis of melanin. Recently, it has been reported that chestnut inner shell extracts inhibited the development of hepatic steatosis in mice fed a high-fat diet. The food industry uses ∼7000 tons of chestnuts annually during the production of marron-glacé, chestnut purée, etc. The peeling process generates a waste product, i.e., the shell, which accounts for ∼10% of the weight of whole chestnuts, and is used as fuel.