Effects of Antidesma thwaitesianum Müll. Arg. Fruit Extract on Radical Scavenging and Apoptotic Properties

Abstract

Antidesma thwaitesianum Müll. Arg. is one of a tropical fruit which is a good source of phenolic compounds. Here, we investigated the in vitro radical scavenging activity and effect of chlorogenic acid (CGA) and A. thwaitesianum fruit extract (AFE) against H2O2-induced cytotoxicity in RAW264.7 macrophage cells. Chemical components in the extract were analyzed by colorimetric method and high performance liquid chromatography. The results exhibited that the amount of total phenolic and total flavonoid contents in AFE were 25.486 ± 0.370 mg of gallic acid equivalents (GAE)/g extract and 7.264 ± 0.312 mg of catechin equivalents (CE)/g extract, respectively, while 114 μg/g crude extract CGA was detected in AFE. AFE showed scavenging activity against ABTS and DPPH radicals, with a 50% inhibition concentration of 11.435 ± 0.381 and 2.063 ± 0.022 mg/mL, respectively. Pretreatment with both CGA (10 µg/mL) and AFE (400 µg/mL) significantly restored cell viability in H2O2-induced cytotoxicity in RAW264.7 macrophage cells, and only CGA at the concentrations of 5 and 10 µg/mL could protect cells from apoptosis. In conclusion, CGA-containing AFE has potent in vitro antioxidant activity and can increase the cell survival in H2O2-induced RAW264.7 macrophage cells. These results support the nutritional and medical value of A. thwaitesianum fruit for health-promoting benefits. Keywords: Antidesma thwaitesianum Müll. Arg., Chlorogenic acid, Antioxidant activity, Anti-apoptotic activity, RAW264.7 macrophage cells