本研究採用20種中草藥為素材，進行美白及抗氧化之生物活性試驗。結果顯示中草藥中玄參(Scrophularia ningpoensis Hemsl.)及青葙子(Celo- sia argentea L.)之乙醇萃取物有明顯抑制老鼠B16黑色素腫瘤細胞黑色素生成之效果，其IC50值(抑制率50%的藥物濃度)分別為118.5及124.8 μg/mL，比熊果素(IC50為136.0 μg/mL)佳；以不同極性之溶劑分配萃取結果發現青葙子95 %甲醇層 IC50值為61.6 μg/mL，比熊果素(IC50 136.0 μg/mL)強2.2倍。另外，在抗氧化作用以DPPH自由基清除能力為試驗，其結果顯示地榆 (Sanguisorba officin- alis L.)及石韋(Pyrrosia lingua (Thunb.) Farw.)之粗萃取物對DPPH自由基清除的能力最強，SC50值(清除率50%的藥物濃度)同樣為4.9 μg/mL比正對照組L-Ascorbic acid (SC50為6.4 μg/mL)強1.3倍。其次為穿山龍(Dioscorea nipponica Mak.) SC50值為6.2 μg/mL。抗自由基有效中藥進一步以不同極性之溶劑分配萃取，結果發現地榆之乙酸乙酯、95 %甲醇、正丁醇和水層(SC50 依序分別為4.4、3.4、5.7、5.4 μg/mL) 及穿山龍乙酸乙酯、95 %甲醇和水層(SC50 依序分別為5.2、3.5、4.2 μg/mL)的DPPH清除自由基能力皆強於L-Ascorbic acid。 The melanogenesis and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activities of Chinese Herbal Medicines were studied in vitro. We examined 20 traditional Chinese herbal medicines that might be useful for skin-whitening and skin health. Extracts (100 μg/mL) were tested for cytotoxicity on human B-16 melanoma cell; 14 exhibited low cytotoxicity. Their effects on melanin inhibitory activities and free radical scavenging activities were further assessed. Scrophularia ningpoensis and Celosia argentea exhibited potent inhibitory effects on melanin (IC50 values 118.5 and 124.8 μg/mL). The MeOH layer of C. argentea showen with IC50 values 61.6 μg/mL higher activities than α-arbutin (IC50 136.0 μg/mL). Sanguisorba officinalis, Pyrrosia lingua, and Dioscorea nipponica (IC50: 4.9, 4.9, and 6.2 μg/mL, DPPH) showed good antioxidative activities and S. officinalis EA, 95% MeOH layer, BuOH, and H2O (IC50: 4.4, 3.4, 5.7 and 5.4 μg/mL, DPPH) and D. nipponica EA, 95% MeOH layer, and H2O (IC50: 5.2, 3.5, and 4.2 μg/mL, DPPH) showed good antioxidative activities than ascorbic acid.
