为进一步探索桉叶提取物抗氧化活性的物质基础，本文采用反相硅胶和制备液相等方法对桉叶提取物中高醇组分进行分离纯化得到4个化合物。接着应用1H-NMR和13C-NMR光谱分析鉴定化合物的结构，最终鉴定出3个化合物，分别为金丝桃苷、番石榴苷和槲皮素-3-O-α-吡喃阿拉伯糖-2”-棓酸盐。最后采用DPPH·、ABTS+·和ORAC三种体外检测体系进行抗氧化活性的研究。在DPPH·和ORAC方法中，番石榴苷的抗氧化能力最强，槲皮素-3-O-α-吡喃阿拉伯糖-2”-棓酸盐的抗氧化能力最低。在ABTS·+方法中金丝桃苷的抗氧化能力最强，番石榴苷的抗氧化能力最低。但与抗氧化剂Trolox相比，三者都表现出更强的抗氧化能力，是有较好发展前景的天然抗氧化剂。本文为桉叶资源的综合开发提供理论指导作用。

To further elucidate antioxidant compounds of Eucalyptus leave extract, four compounds were isolated and purified from the fraction P95 of eucalyptus leave extract by medium-pressure silica gel column chromatography and preparative high performance liquid chromatography (HPLC). And three of the compounds were identified as hyperoside, guava glycosides and quercetin-3-o- alpha-pyranol-2"-gallate, by comparison of their 1H-NMR and 13C-NMR data. Then 1,1-diphenyl-2-picrylhydrazyl (DPPH·), 2,2‘-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS+·), and oxygen radical absorbance capacity (ORAC) assays were used for analyzing the antioxidant activity of the compounds. Among the DPPH and ORAC methods, guava glycosides showed the highest antioxidant activity, and quercetin-3-o- alpha-pyranol-2"-gallate showed the lowest antioxidant capacity. Hyperoside had the highest antioxidant activity, and guava glycosides had the lowest in ABTS+·assay. All of three compounds showed higher antioxidant activity than trolox, and they were natural antioxidants with better development prospects. This study provided a theoretical guidance for the comprehensive development of the Eucalyptus leaves.

国家重点研发计划-人工林非木质林产资源高质化利用技术创新（2016YFD0600806）；广东省自然科学基金博士启动项目（2015A030310118）；广东省科技计划项目（2017A020208042）