以清除DPPH自由基檢測精油成份中十四種醛類與醇類之抗氧化力研究

本研究係以精油常見之十四種精油成分對於清除DPPH自由基能力與其作用分析。研究結果顯示十四種試驗樣品中以檸檬醛(Citral)之抗氧化力最為顯著，於0.2g/ml時抗氧化力達92.68%，其EC_(50)之濃度為40.174 mg/ml，芳樟醇(Linalool)抗氧化力達90.54%，其EC_(50)之濃度為76.620 mg/ml，橙花醇(Citronellol)抗氧化力達83.81%，其EC_(50)之濃度為156.231 mg/ml。依照實驗結果，進一步以清除力前三名及前五名單獨化學成分固定比例混合測定，其清除能力分別達預估值的99.48%及98.25%。顯示不同精油成分之間清除DPPH自由基能力有加成作用。因此未來透過持續的資料庫累積，運用GCMS檢測精油成分及所含百分比，即可簡易估算出精油清除DPPH自由基能力。

關鍵字

醛；醇；精油； DPPH ；抗氧化； EC_(50)

並列摘要

This study designed to examine the antioxidant activity of the basic 14 chemical compounds from essential oils by utilizing DPPH radical-scavenging activity. Among these 14 chemical compounds, the result was shown that the Citral revealed the highest degree of antioxidant activity in terms of DPPH radical-scavenging activity. The value of antioxidant activity was 92.68% and the EC_(50) value was 40.174 mg/ml measuring in 0.2g/ml. The antioxidant activity and EC_(50) value of Linalool were 90.54% and 76.76 mg/ml, respectively. As well as for Citronellol, the values were 83.81% and 156.231 mg/ml. According to the further study, the value of DPPH radical-scavenging activity could reach about 99.48% and 98.25% by proportionally mixing the top 3 and top 5 chemical compounds of essential oils, which was shown that there is a positive correlation in between the different chemical compounds of essential oils. Therefore, after continuously establishing the database in the future, we could estimate the DPPH radical-scavenging activity of essential oils by detecting the percentage of their compositions by using GC-MS.