가지의 품종별, 부위별 추출물의 항산화 효과

The antioxidative activities of two varieties of egg plant (Chunyang No 2: Dangaji, Jinju Janggaji: Janggaji) extracts were investigated. The total polyphenol contents of Dangaji peel hot water extract and the Janggaji flesh and fruit hot water extracts were higher than those of the other samples. However, the DPPH radical scavenging activities(electron donating activity) of Dangaji flesh-ethanol, peel-cold water, and fruit- ethanol extracts, as well as the Janggaji peel cold water extract, were higher than those of the other samples. Furthermore, the in vitro inhibitory effects of the Dangaji peel cold water and hot water extracts on rat hepatic xanthine oxidase were highest among the samples, and were exhibited in a dose dependant manners. Although there were marked changes in the xanthine oxidase Km values for xanthine as a substrate, the Vmax value changes by the addition of the Dangaji water extracts were minor compared with the control. This result suggests that Dangaji water extracts may regulate the activity of xanthine oxidase-via the inhibition of binding affinity between the enzyme and substrate. The present study provides experimental evidence that constituents of egg plant extracts may ameliorate reactive oxygen species(ROS)-induced oxidative stress via hepatic hepatic xanthine oxidase activity, but further studies to identify the active antioxidants and compounds and inhibitors of xanthine oxidase are required.