[关键词]
[摘要]
目的 比较分析民族药用植物桃金娘Rhodomyrtus tomentosa的叶、枝和果实的特征性化学成分,并对其果实开展化学成分研究。方法 采用高效液相色谱-飞行时间质谱(HPLC-TOF-MS)分析,结合主成分分析(PCA)和偏最小方差判别分析(OPLS-DA)获得不同部位差异性成分。通过正相硅胶、凝胶(Sephedex LH-20)以及循环制备高效液相(RE-HPLC)等多种色谱手段对桃金娘果实成分进行分离纯化,根据波谱数据对化合物结构进行鉴定。结果 PCA分析显示桃金娘叶中的成分单独成为一支,枝、果两部分合为一支(枝、果两部分存在重合),说明叶的化学成分同枝、果两部分存在较大差异,而枝和果两部分成分差异不大。利用OPLS-DA分析、色谱峰保留时间、精确相对分子质量、元素组成分析检索以及文献比对,从叶中鉴定出4个标识性化合物,分别为杨梅苷(1)、杨梅素-3-O-L-呋喃阿拉伯糖苷(2)、鸢尾苷(3)和3,3'-二去甲基-9-羰基-松脂醇(4);并从桃金娘果实中分离了5个化合物,分别鉴定为maslinic acid (5)、没食子酸乙酯(6)、没食子酸(7)、白藜芦醇(8)和白皮杉醇(9)。结论 为桃金娘不同部位差异性成分的识别提供了新方法,同时也为研究同种生物不同部位所具有不同药理活性的差异成分提供新的思路。
[Key word]
[Abstract]
Objective To compare chemical composition in the different parts (leaf, branch, and fruit) of Rhodomyrtus tomentosa, and to study the chemical constituents from fruits of R. tomentosa.Methods High performance liquid chromatography/time-of-flight mass spectrometry (HPLC-TOF-MS) method was executed to analyze the samples. Principle component analysis (PCA) and partial minimum variance discriminant analysis (OPLS-DA) in MassLynx XS software were used to analyze the obtained data. The chemical constituents of fruits were isolated and purified by column chromatography, including silica gel, Sephedex LH-20 and re-HPLC, and the structures were elucidated based on their NMR and MS data.Results The PCA results indicated that the constituents existed in leaf were significantly different from those in branch and fruit, while constituents in branch and fruit were similar. Furthermore, based on OPLS-DA, combined with chromatographic retention regulation, accurate molecular mass, isotopic matching and literature searching, four marker compounds from leaves had been found and identified as myricitrin (1), myricitrin-3-O-L-furanoarabinoside (2), iridin (3), and 3,3'-didemethyl-9-oxo-pinoresinol (4). Besides, five compounds were isolated from fruits and identified as maslinic >acid (5), ethyl gallate (6), gallic acid (7), resveratrol (8), and piceatannol (9).Conclusion This research provides an effective strategy for analyzing chemical difference from different parts of R. tomentosa, which can be applied to study the chemical difference from different parts of other species.
[中图分类号]
[基金项目]
国家外专局、教育部“111工程”项目(B08044);国家自然科学基金面上项目(31070288);国家自然科学基金国际(地区)合作与交流项目(31761143001);科技部国家科技基础性工作专项(2012FY110300)