柿酢飲用による血中抗酸化能および尿中イソプロスタンレベルの変化

Abstract

To clarify the antioxidative effects of kakisu (persimmon vinegar), plasma antioxidant power and urinary oxidative stress level in healthy subjects were measured using enzyme immunological assays. Eighty-one subjects (age 30-69, 58.4 +/- 0.8) were randomly divided into two groups using a crossover design. Group A drank kakisu for 56 days starting in March, whereas group B drank kakisu for 54 days starting in June. Copper reducing equivalent level in plasma was measured as antioxidant power, and urinary 8-isoprostane (8-iso-prostaglandin F2alpha) level was measured as oxidative stress marker. Baseline plasma antioxidant power and urinary 8-isoprostane level showed no significant correlation among the subjects in this study. By drinking kakisu for 8 weeks, total antioxidant power significantly increased, and urinary 8-isoprostane level decreased. Total antioxidant power increased more markedly in group A than in group B. In contrast, urinary oxidative stress level decreased more markedly in group B than in group A. Smoking habits significantly correlated with urinary 8-isoprostane level. Males were more sensitive to the antioxidative effects of kakisu than females. Kakisu has antioxidative effects that increase plasma antioxidant power and reduce urinary 8-isoprostane level. Further study is needed to clarify the influence of season and gender on such antioxidative effects.