桉树种植面积广阔，每年产生大量的桉叶废弃物，提高桉叶资源利用率对促进社会经济有重要意义。本项目组发现桉叶重要抗氧化成分PGG(五没食子酰葡萄糖)和OEB(月见草素B)均具有较强的体外抗氧化能力，并能提高秀丽线虫平均寿命。然而，只有OEB显著降低线虫体内活性氧积累量。迄今为止，PGG与OEB对线虫抗氧化及延缓衰老的活性差异及分子机制尚不清楚。因此，本项目采用秀丽线虫模型来研究PGG与OEB抗氧化及延缓衰老的活性差异及分子机制，重点研究在Insulin/IGF-1信号通路中两者对抗氧化基因，以及调控寿命关键基因和蛋白表达水平的变化，最后从分子生物学角度深入探讨PGG与OEB的抗氧化及延缓衰老的分子机制。研究结果对于揭示两者的物质结构和功能关系具有重要意义，为探索其在哺乳动物中的抗氧化及延缓衰老分子机制提供作用靶点信息，并为桉叶多酚精深加工提供理论依据。

Eucalyptus is being established largely in plantations in China, but a great deal of Eucalyptus leaves are waste every year because of the limit exploitation and processing. So it is vital for the economic to improve the Utilization of Eucalyptus leaves. The important composition of Eucalyptus leaves PGG and OEB showed strong antioxidant activity in vitro and improved the median lifespan of Caenorhabditis elegans. Surprisingly, only OEB could lower significantly the accumulation of reactive oxygen species. So far, the molecular mechanism and the difference of antioxidant activity and antiaging effect between PGG and OEB is still not clear. Therefore, in this project the model of C. elegans, a widely used model, will be used to reveal the molecular mechanism and the difference of antioxidant activity and antiaging effect between PGG and OEB. The project will focus on the antioxidant activity and antiaging effect between PGG and OEB, determination the expression levels of related genes and proteins in the important signal pathways of regulating lifespan (Insulin/IGF-1), and elucidation of the molecular mechanism of antioxidant activity and antiaging effect between PGG and OEB. The proposed studies will supply the important information on the relationship of structure and function between PGG and OEB, have a great reference meaning for the related molecular mechanism in mammal, and supply theoretical basis for the development of Eucalyptus polyphenols.