木瓜叶多酚的提取及抗氧化活性研究

以提取木瓜叶多酚并研究其抗氧化活性为目的。利用乙醇提取木瓜叶多酚,采用DPPH法、水杨酸法检测其对DPPH.和.OH的清除作用。结果表明,最佳提取条件为提取温度70℃、乙醇体积分数70%、提取时间2.5 h、料液比1∶15(m/V)。在该条件下木瓜叶多酚得率最高,达到18 mg/g。木瓜叶多酚清除DPPH.和.OH的半抑制质量浓度(EC50)分别为67μg/mL和0.44 mg/mL。结论为木瓜叶中含有丰富的多酚,并且其具有较强的抗氧化活性。

Study on the Extraction and Antioxidant Activity of Polyphenols from Papaya Leaf

The aim was to extract polyphenols from papaya leaf and study their antioxidant activities.The polyphenols from papaya leaf were extracted by ethanol,and their scavenging abilities for DPPH· and ·OH free radical were examined by DPPH· and salicylic acid methods.The results showed that: the optimal extracting temperature,the ethanol concentration,the extracting time,and the ratio of solid to liquid were 70 ℃,70%(V/V),2.5 h,and 1:15(g/mL),respectively.Under the optimal conditions,the extraction yield of polyphenols was 18 mg/g.Moreover,the EC50 values of the polyphenols against DPPH· and ·OH free radical were 67 μg/mL and 0.44 mg/mL,respectively.The conclusions indicated that: the abundant polyphenols were present in papaya leaf,which showed good antioxidant activities.