Wang Bo, Jiao Shirong, Liu Hengchuan, Hong Junrong
West China School of Public Health, Sichuan University, Chengdu 610041, China.
Wei Sheng Yan Jiu. 2007 May;36(3):298-300.
To study the antioxidative activities of the extracts from Psidium guajava Linn leaves (PGL).
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).
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 (EC50) on scavenging hydroxyl radicals of 0.63, 0.47 and 0.58g/L, had EC50 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.
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.
研究番石榴叶提取物的抗氧化活性。
分别用蒸馏水、65%乙醇和95%乙醇浸泡番石榴叶。溶液经过滤、浓缩和干燥后得到3种提取物。分析这3种提取物对羟自由基的清除率和对脂质过氧化的抑制率。采用紫外分光光度法测定其总黄酮含量，并用高效液相色谱法（HPLC）和紫外可见吸收光谱法（UV）初步鉴定总黄酮的成分。
蒸馏水、65%乙醇和95%乙醇提取物对羟自由基的清除和脂质过氧化的抑制均呈剂量依赖性，清除羟自由基的半数有效浓度（EC50）分别为0.63、0.47和0.58g/L，抑制脂质过氧化的EC50分别为0.20、0.035、0.18g/L，总黄酮含量分别为3.28、30.71和55.98g/kg。
番石榴叶水提取物和乙醇提取物在本研究中具有潜在的抗氧化活性。黄酮类化合物可能是其抗氧化成分之一。
