The objective of this study was to investigate the antioxidant activity of Korean yam (Dioscorea batatas DECNE.) by different extraction solvents including 70% methanol, 70% ethanol and chloroform–methanol mixture (CM, 2:1, v/v). Raw yam was analyzed for its color property, total phenol content and antioxidant activity. Yam possessed high L* value and H° value, which were 81.64±2.59 and 83.36±0.15, respectively. Raw yam was found to have great antioxidant activity evaluated through ABTS [2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt] radical scavenging activity, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, reducing power, and ferric reducing antioxidant power. Total phenol contents of various extracts from raw yam increased in the following order: 70% methanol extract (37.62±0.88 mg CAE/g), 70% ethanol extract (43.38±0.66 mg CAE/g) and CM extract (67.17±0.12 mg CAE/g), respectively. The same trend was also could be found in the ABTS radical scavenging activity, DPPH radical scavenging activity and ferric reducing antioxidant power assays. These results implied that Korean yam might play an important role in antioxidation and serve as the bio-health functional food to take a good part in prevention of human diseases and aging.

• Yishan Duan(Department of Food Science and Technology, Pusan National University, Miryang 50463, Korea)
• Gyeong-Hwuii Kim(Department of Biological Science and Technology, Yonsei University, Seoul 03722, Korea)
• Han-Soo Kim(Department of Food Science and Technology, Pusan National University, Miryang 50463, Korea) Corresponding author