藍花楹花部抗氧化活性之研究

Antioxidant Activity of Jacaranda Acutifolia Flower

藍花楹（Jacaranda acutifolia Humb. ）為紫葳科落葉喬木，原產於美洲熱帶地區，為世界著名觀賞樹木，台灣引進栽培為庭院觀賞植物，亦可供行道、街道植栽之用。本研究以藍花楹花部丙酮萃取物進行抗氧化活性測試。測定項目包含自由基（2,2- 二苯基苦味胼基團，DPPH ）清除能力，螯合亞鐵離子之能力（chelating ability on ferrous ions ）、還原力（reducingpower ）及總酚類含量（total phenol content ）評估。結果顯示乙酸乙酯可溶層擁有較高的抗氧化活性，其清除DPPH 自由基能力為（EC50 = 0.049 mg/mL ）及螯合亞鐵離子能力為（EC50 =0.125 mg/mL ），總酚類含量為（17.20 mg/g as gallic acid ）。此研究證實藍花楹花部具有抗氧化活性研究開發的潛力。Jacaranda acutifolia Humb. (Bignoniaceae) is a cultivated species in Taiwan area as an ornamental plant. The antioxidant activity of the acetone extract and its subfractions of Jacaranda acutifolia flower were evaluated using different antioxidant methodologies: DPPH free radical scavenging, chelating activity on ferrous ion and reducing power. The total phenolic content of these extracts was determined as the gallic acid equivalent. The antioxidant activities of all extracts were concentration-dependent and consistent with the total phenolic content. The ethyl acetate soluble fraction (EF) of Jacaranda acutifolia flower possessed the highest antioxidant activities, including effective DPPH radical scavenging (EC50 = 0.049 mg/mL) and ferric ion reducing activities (EC50 = 0.125 mg/mL). The total phenolic contents were estimated as 17.20 mg/g gallic acid equivalents. These results demonstrated the antioxidant potential of the extracts of Jacaranda acutifolia flower.