Comparison of Antioxidant Properties of Different Crude Extracts from Citrus natsudaidai Peel

抄録

Citrus natsudaidai is a popular citrus in Japan, but the peel is of limited use and its composition is not well documented. The purposes of this study were to obtain health-beneficial compounds from C. natsudaidai peel for food use by simple methods and to investigate the antioxidant capacities of extracts of different polarities without overestimating the effects. C. natsudaidai peel was extracted with water-ethanol and hexane-ethanol solutions to obtain five different soluble fractions. The highest total phenolic content (TPC) was obtained from the water-soluble fraction (WSF), and the lowest content was observed in the hexane soluble fraction (HSF). The WSF also showed the highest antioxidant activities, and the lowest activities were found in HSF. A positive correlation was detected between TPC and antioxidant activities. The polar extract of C. natsudaidai peel has potential as a natural additive or ingredient in foods, cosmetics and pharmaceutical products with antioxidant activity.