桉叶多酚提取物体内外抗氧化活性评价

Antioxidant Activity of Eucalyptus Leaf Polyphenol Extract in Vitro and in Vivo

桉叶资源丰富且生物活性高,但少有研究对桉叶多酚提取物进行系统的抗氧化活性评价。本实验旨在研究纯化后桉叶多酚提取物体内外抗氧化活性。以化学法、RAW264.7巨噬细胞模型、秀丽隐杆线虫(以下简称线虫)模型为评价方法,以自由基清除率、抗氧化酶活力及线虫寿命等为指标,评价桉叶多酚提取物的抗氧化能力。结果表明,桉叶多酚提取物具有良好的自由基清除能力和还原能力,在一定质量浓度下效果接近抗坏血酸。桉叶多酚提取物能显著提高氧化损伤RAW264.7巨噬细胞内抗氧化酶(超氧化物歧化酶、过氧化氢酶)活力和谷胱甘肽含量,并显著降低丙二醛含量(P<0.05),呈量效关系。此外,桉叶多酚提取物显著降低常规培养和氧化损伤条件下线虫体内活性氧积累量(P<0.05),提高线虫抗氧化能力,起到延长线虫寿命的作用。桉叶多酚提取物在体内外均表现出良好的抗氧化活性,具备开发食品抗氧化剂或功能食品的潜力。

Eucalyptus leaves are valued as an enormous resource with various biological activities,but rare information is available concerning systematical evaluation of the antioxidant activity of eucalyptus leaf polyphenol extract.Therefore,the aim of this study was to evaluate the antioxidant activity of purified eucalyptus leaf polyphenol extract(PEPE)in vitro and in vivo.The in vitro antioxidant activity was evaluated through the determination of free radial scavenging capacity and total reducing power by chemical assays.The in vivo antioxidant activity was assessed using RAW264.7 cells and Caenorhabditis elegans.Results showed that PEPE had potent free radical scavenging capacity and reducing power,which was equivalent to the effect of ascorbic acid at a certain concentration.PEPE treatment significantly dose-dependently increased the activities of the antioxidant enzymes(superoxide dismutase and catalase)and glutathione content in RAW264.7 cells with oxidative injury and reduced malondialdehyde content(P<0.05).In addition,PEPE suppressed reactive oxygen species accumulation in the nematodes under normal and oxidative damage conditions(P<0.05),enhanced their antioxidant capacity and prolonged their lifespan.In conclusion,PEPE has a strong antioxidant activity both in vivo and in vitro,and thus possesses the potential to be developed as food antioxidants or an ingredient in functional foods.