紫蘇不同部位水萃物之抗氧化能力研究   全文下載

Comparative Antioxidant Properties of Water Extracts from Different Parts of Beefsteak Plant (Perilla frutescens)

本研究主要探討紫蘇（beefsteak plant）梗（BS）、葉（BL）、子（BR）不同部位之水萃物抗氧化活性與酚類化合物含量。在濃度5 μg/mL時，發現紫蘇梗（BS）水萃物有較佳超氧陰離子清除活性（61.8%），其次葉（BL）為60.8% 、最後子（BR）為33.3%。在DPPH捕捉力方面，紫蘇梗（BS）水萃物有很強活性（54.8%）。與對照組相比較，紫蘇梗（BS）、葉（BL）、子（BR）之水萃物都具有較強的還原力和亞鐵離子螯合能力。紫蘇梗（BS）的總酚類化合物及類黃酮含量遠高於其他部位。研究結果顯示紫蘇梗（BS）水萃物具有很好之抗氧化活性，特別是游離自由基清除活性、超氧陰離子清除活性和還原力。未來將進一步分析紫蘇梗（BS）水萃物抗氧化成分，並且開發紫蘇梗（BS）成為新的保健食品添加物或特定功效之食品。

Water extracts from beefsteak plant stems (BS), leaves (BL), and ripe seeds (BR) were examined for their antioxidant activities and phenolic compounds. Based on superoxide anion radicals scavenging activity, the BS extract (61.8%) is the most effective one followed by BL and BR extract (60.8% and 33.3%, respectively). The antioxidant activity determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method revealed that the BS extract had the highest activity on DPPH free radicals (54.8%). In addition, the extracts of BS, BL and BR were effective in reducing capacity and chelating effect on ferrous ions in comparison with the control. Total phenolic compound and flavonoid content of the BS extract was found to be superior to other beefsteak plant extracts. The results indicated that the BS extract of beefsteak plant has effective antioxidant functions, especially in superoxide anion radical and DPPH radical scavenging activities and reducing power. It was of our paramount interest to further identify the specific antioxidant components in BS which may be a new health-care food supplement or functional food for special use in the future.