| The present study was aimed to investigate the antioxidative effect of Alpinia conchigera extracts in various solvents, i.e. hexane, ethyl acetate, and hexane. The studies were composed of total phenolic content determination, free radical scavenging activity; DPPH and ABTS assay, and reducing power; FRAP and FTC assay compared with vitamin C and trolox. The phenolic contents of hexane, ethyl acetate, and methanol extracts were 34.80±0.06, 120.44±0.01, and 23.06±0.01 µg/mg, respectively. The free radical scavenging activities were examined by DPPH which demonstrated a scavenging power with IC50 of 54.48±6.89, 12.32±0.28, and 71.64±2.46 µg/ml for hexane, ethyl acetate, and methanol extracts, respectively. The results of ABTS assay expressed in TEAC (Trolox Equivalent Antioxidative Capacity) of hexane, ethyl acetate, and methanol were 2.87±0.88, 26.02±1.92, and 7.75±1.06 µg /mg, respectively. The reducing power of hexane, ethyl acetate, and methanol extract studied by using FRAP assay were 184.90±24.68, 1,163.30 ±47.71, and 302.24±11.11 µg Fe2+/mg, respectively. The FTC assay demonstrated percent of antilipidperoxidation activity showed that ethyl acetate extract had the highest and higher than those of hexane and methanol extract. |