송희순, 박연희, 정세흥
Nov 1, 2006
Journal of The Korean Society of Food Science and Nutrition
Smilax china root has been used as traditional medicinal remedy in China and Korea and reported to have various biological activities such as anti-inflammatory, antimutagenic and antimicrobial activities. In this study, the possibility of development as natural antioxidants of Smilax china root extracts was investigated. For the evaluation of antioxidant activity, aqueous- and 25% EtOH extract from Smilax china root were prepared and six different evaluation assay methods, i.e., measurement of total phenolics, radical scavenging effects on 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide (NO) and nitrite (NO₂), reducing power, and inhibitory effect on tyrosinase activity, were used. The total phenolics content of two extracts was high as the level of 36 ㎎ of gallic acid equivalent per 1 g of dried sample tested. The radical scavenging activities of ethanol extract toward DPPH and NO were better than those of aqueous extract (p＜0.05). The NO₂ scavenging activity of both extracts showed the highest value at pH 1.2 (98%). Especially, the NO₂ scavenging activities of EtOH extract were significantly stronger than those of aqueous one at pH 4.2 (51%) and pH 6.0 (32%), respectively. In the reducing power test, both extracts revealed higher ferric ion reducing activity than known antioxidant, vitamin C at the level of 0.05~0.1 ㎎/mL (p＜0.01). The 1 mL of aqueous- and 25% EtOH extract showed effective inhibition activity on tyrosinase activity as 45% and 53%, respectively. Therefore, these results suggest that two extracts from Smilax china root may serve as useful natural antioxidants.