Masoko P, Mdee L K, Mampuru L J, Eloff J N
Department of Paraclinical Sciences, Faculty of Veterinary Sciences, Phytomedicine Programme, University of Pretoria, Onderstepoort, South Africa.
Nat Prod Res. 2008;22(12):1074-84. doi: 10.1080/14786410802267494.
Antifungal bioassay-guided fractionation of Combretum nelsonii leaf extracts afforded two closely related triterpenes, asiatic acid and arjunolic acid. Antifungal activities of the mixture of asiatic acid and arjunolic acid were determined against five fungal animal pathogens. The minimum inhibitory concentrations of the mixture to the different pathogens varied from 0.2 to 1.6 microg mL(-1); Candida albicans (0.9 microg mL(-1)), Cryptococcus neoformans (0.4 microg mL(-1)), Aspergillus fumigatus (1.6 microg mL(-1)), Microsporum canis (0.2 microg mL(-1)) and Sporothrix schenckii (0.2 microg mL(-1)). Microsporum canis and S. schenckii were the most susceptible followed by C. neoformans. Aspergillus fumigatus was the most resistant. The R(f) value of the mixture of asiatic acid and arjunolic acid was 0.27 in CEF (chloroform : ethylacetate : formic acid), 0.09 (BEA; benzene : ethanol : ammonium hydroxide) and 0.55 (EMW; ethylacetate : methanol : water) which was active against all pathogens. In vitro cytotoxicity of mixture gave an LC(50) of 10.58 microg mL(-1) towards Vero monkey kidney cells.
对尼尔森风车子叶提取物进行抗真菌生物测定引导的分级分离，得到了两种密切相关的三萜类化合物，积雪草苷和阿江榄仁酸。测定了积雪草苷和阿江榄仁酸混合物对五种真菌性动物病原体的抗真菌活性。该混合物对不同病原体的最低抑菌浓度在0.2至1.6微克/毫升之间；白色念珠菌（0.9微克/毫升）、新型隐球菌（0.4微克/毫升）、烟曲霉（1.6微克/毫升）、犬小孢子菌（0.2微克/毫升）和申克孢子丝菌（0.2微克/毫升）。犬小孢子菌和申克孢子丝菌最敏感，其次是新型隐球菌。烟曲霉最耐药。积雪草苷和阿江榄仁酸混合物在CEF（氯仿：乙酸乙酯：甲酸）中的Rf值为0.27，在BEA（苯：乙醇：氢氧化铵）中为0.09，在EMW（乙酸乙酯：甲醇：水）中为0.55，对所有病原体均有活性。混合物的体外细胞毒性对非洲绿猴肾细胞的LC50为10.58微克/毫升。
