番石榴叶提取物对小鼠肝脏抗氧化作用研究

目的研究番石榴叶提取物抗氧化活性。方法干燥的番石榴叶分别用蒸馏水、65%和95%乙醇浸提,浸提液过滤、浓缩、干燥得到3种提取物。测定各提取物对羟自由基清除率和脂质过氧化抑制率。紫外分光光度法分析提取物中总黄酮含量,高效液相色谱(HPLC)和紫外可见吸收光谱法(UV)对黄酮类化合物初步鉴定。结果水、65%和95%乙醇提取物均具有清除羟自由基和抑制脂质过氧化作用,且呈剂量-效应关系,对羟自由基清除作用的半数有效浓度(EC50)分别为0.63、0.47和0.58g/L,对脂质过氧化抑制作用的半数有效浓度(EC50)分别为0.20、0.035和0.18g/L,总黄酮含量分别为3.28、30.71和55.98g/kg。结论番石榴叶水和乙醇提取物具有较强的抗氧化作用,其中黄酮类化合物可能是其功效成分之一。

Study on antioxidative activities of Psidium guajava Linn leaves extracts

Objective To study the antioxidative activities of the extracts from Psidium guajava Linn leaves(PGL). Methods The PGL was submersed with distilled water, 65% ethanol and 95% ethanol respectively. The 3 extracts were obtained after the solutions were filtered, concentrated and dried. The scavenging rate to hydroxyl radicals and inhibiting rate to lipid peroxidation were analyzed for the 3 extracts. Their contents of total flavonoids were determined by ultraviolet spectrophotometry, and the components of total flavonoids were primarily identified by high performance liquid chromatography (HPLC) and ultraviolet-visible absorption spectrometry (UV). Results The extracts from distilled water, 65% ethanol and 95% ethanol respectively showed effects on scavenging hydroxyl radicals and inhibiting lipid peroxidation in the dose-dependent manner, had 50% effective concentration (EC_ 50 ) on scavenging hydroxyl radicals of 0.63, 0.47 and 0.58g/L, had EC_ 50 on inhibiting lipid peroxidation of 0.20, 0.035, 0.18g/L and had total flavonoids contents of 3.28, 30.71 and 55.98g/kg respectively. Conclusion The aquatic and the ethanol extracts from PGL possess the potential antioxidative activities in the study. The flavonoids may be one of their antioxidative components.