Experiment on Antioxidant and Anti-inflammatory Activity of Different Extracts from Leaves of Tetrastigma hemsleyanum

In May 2022, leaves of 3-year Tetrastigma hemsleyanum were collected in Suichang, Zhejiang province. Four extracts were obtained from leaves by different reagents (petroleum ether, ethyl acetate, water saturated n-butanol, water). Determinations were implemented on total flavonoids and polyphenols content, and DPPH, FRAP and total antioxidant activity methods were used to evaluate antioxidant activities of different extracts. The anti-inflammatory activity of the different extracts was evaluated by an LPS-induced inflammation model of RAW 264.7 cells by measuring cytokine nitric oxide. The correlation was further analyzed by HPLC. The result demonstrated that extract by ethyl acetate had the highest content of total flavonoids and polyphenols, 145.82±3.09 mg/g and 27.18±1.01 mg/g, and the strongest antioxidant capacity. Extract by petroleum ether had the strongest anti-inflamatory capacity. Correlation analysis showed that the content of total flavones and polyphenols had evident effect on antioxidant capacity (P < 0.01), but no significant effect on anti-inflammatory capacity (P > 0.05). HPLC analysis resulted that rutin and chlorogenic acid may be antioxidant-related components of extracts from leaves of T. hemsleyanum.