鐵刀木(Cassia siamea)為台灣常綠木本植物，各地栽植為庭園樹或行道樹。將鐵刀木之不同部位以水、50%酒精與95%酒精分別萃取之萃取物進行抗氧化活性研究。結果顯示，皮部50%酒精萃取物具有較佳之抗氧化活性。同時，總多酚類含量與總黃酮含量以葉部95%酒精萃取物為最佳。
This study was aimed to evaluate the antioxidant activities of extracts obtained from the different part of Cassia siamea. The antioxidant activities, including the radical-scavenging effect, reducing power, and the activities correlated with both the total phenol and total flavonoid contents. It was found that the antioxidant activities of all the extracts increased with the increase of their concentration, and possessed antioxidant characteristics including the radical-scavenging effect, and reducing power. The 50% ethanolic extracts of Cassia siamea bark (CBE50) showed the most powerful scavenging activities against DPPH radicals (IC50=0.330 mg/ml) and contained the highest total phenolic content as 139.255 mg/g gallic acid equivalents (GAE). The 95% ethanolic extracts of Cassia siamea leaves (CLE95) contained the highest total flavonoid contents as 156.397 mg/g guercetin equivalents (GE). The results provide the useful information's on pharmacological activities.
