云南萝芙木根中吲哚生物碱及其抗菌活性

Indole alkaloids from roots of Rauvolfia yunnanensis and its antibacterial activities

目的 研究云南萝芙木Rauvolfia yunnanensis根中的吲哚类生物碱化学成分及抗菌活性,明确该植物抗菌活性成分。方法 采用硅胶柱色谱、RP-C18、Sephadex LH-20、半制备HPLC等方法进行分离纯化,结合波谱数据及文献参数对化合物进行结构鉴定,并采用微量肉汤稀释法对单体化合物进行抗菌活性评价。结果 从云南萝芙木根醋酸乙酯部位共分离得到20个吲哚类生物碱化合物,分别鉴定为维诺任碱(1)、霹雳萝芙木碱(2)、四叶萝芙木新碱(3)、萝加灵(4)、西特斯日钦碱(5)、缝籽木醇(6)、柯楠醇(7)、二氢柯楠醇(8)、毛茶碱(9)、异毛茶碱(10)、佩立任碱(11)、10-羟基-16-表-花菊醇(12)、育亨宾(13)、降马枯星碱B(14)、洛柯碱(15)、阿枯米定碱(16)、去乙酰阿枯米灵(17)、利血平(18)、哈尔满碱(19)、梅林诺宁F(20)。其中化合物20对白色念球菌表现出较好的抗菌活性,最低抑菌浓度(minimum inhibitory concentration,MIC)值为3.12μg/mL,与临床抗真菌药物氟康唑的MIC值相同。化合物1、11对大肠杆菌,化合物11、13、20对枯草芽孢杆菌均表现出一定的抗菌活性,MIC值为6.25~12.50μg/mL,活性与植物源抗菌药物小檗碱相当。结论 化合物20为首次从萝芙木属中分离得到,化合物6、8~13、16~18均为首次从该植物中分离得到,部分单体化合物表现出潜在抗菌活性。

Objective To study the indole alkaloids from the roots of Rauvolfia yunnanensis, and its antibacterial activities, so as to clarify the antibacterial active ingredients of the plant. Methods The constituents were isolated and purified by silica gel column chromatography(CC), RP-C18, Sephadex LH-20 and semi-preparative chromatography, their structures were identified by the combination of physicochemical properties, spectral data and literature comparison. Then, the antibacterial activities of these compounds were detected by the method of micro broth dilution. Results Totally twenty indole alkaloids were obtained and identified as vinorine(1), perakine(2), tetraphyllicine(3), raugalline(4), sitsirikine(5), geissoschizol(6), corynantheol(7),dihydrocorynantheol(8), antirhine(9), isoantirhine(10), pelirine(11), 10-hydroxy-16-epi-affinine(12), yohimbine(13), normacusine B(14), lochnerine(15), akuammidine(16), deacetylakuammiline(17), reserpine(18), harman(19) and melinonine F(20). Moreover,compound 20 showed significant antibacterial activity against Canidia albicans with MIC value of 3.12 μg/mL. Compounds 1 and 11showed certain antimicrobial activity against Escherichia coli, and compounds 11, 13, and 20 showed certain antimicrobial activity against Bacillus subtilis, the MIC values were 6.25—12.50 μg/mL respectively. And their activities were comparable to antibiotics berberine. Conclusion Compound 20 was firstly reported from the genera Rauvolfia, and compounds 6, 8—13, 16—18 were firstly reported from this plant. Some compounds showed potential antimicrobial activities.