Antioxidant Activities and α-Glucosidase Inhibitory Effect of Water Extracts from Medicinal Plants

*Well-being Bioproducts RIC Center, Kangwon National University, Chuncheon 200-701, Korea.**Department of Bio and Health Technology, Kangwon National University, Chuncheon 200-701, Korea.ABSTRACT : We studied the total polyphenol content, DPPH radical scavenging activity, hydroxyl radical scavengingactivity and α-glucosidase inhibition of water extracts from 17 medicinal plants. Total polyphenol contents ranged from 10.0(Coix lachryma-jobi L, CL) ~ 279.7 (Perilla sikokiana, PS) ㎎/g. The water extract from medicinal plants were evaluated forits free radical scavenging activities and compared with a commercial antioxidant, ascorbic acid. DPPH radical scavengingactivity of Pyrus pyrifolia (PP), Chamaecyparis obtusa L. (COL), Chamaecyparis obtusa F. (COF), and PS were higher thanpositive control. Higher hydroxyl radical scavenging activity were shown in Acanthopanax senticosus (AS) and Cordycepsmilitaris (CM) than the other plants. The highest anti-α-glucosidase activity was observed in Cornus officinalis (CO) andPaeonia suffruticosa Andrews (PSA) water extracts. PSA showed not only the higher DPPH radical scavenging activity butalso the anti-α-glucosidase activity. The results of our study that PP, COL, COF, PS, AS, CM, CO and PSA could be poten-tial candidates for natural antioxidants.Key Words : DPPH, Free radical, Antioxidant, α-Glucosidase, Antidiabetic