Research Institute for Medicines and Pharmaceutical Sciences (iMed.UL), Faculdade de Farmácia, Universidade de Lisboa, Av. D. Forças Armadas, 1600-083 Lisboa, Portugal.
J Ethnopharmacol. 2011 Sep 1;137(1):114-20. doi: 10.1016/j.jep.2011.04.062. Epub 2011 May 5.
Several medicinal plants are traditionally used in Mozambique to treat tuberculosis and related symptoms.
It was aimed to assess the in vitro antimycobacterial activity of crude extracts from fifteen medicinal plants and to reveal main classes of compounds which may account for the activity of extracts.
The plant materials were sequentially extracted by n-hexane, dichloromethane, ethyl acetate, and 70% ethanol. Decoction of each plant material was also prepared according to traditional use. Broth microdilution method was employed to screen extracts against two mycobacterial species: Mycobacterium smegmatis ATCC 607 and Mycobacterium tuberculosis H37Rv. The extracts with minimum inhibitory concentration(s) (MIC) below 125 μg/mL were considered active and further tested against different mycobacterial species and strains, namely Mycobacterium tuberculosis H37Ra, Mycobacterium bovis BCG ATCC 35734, Mycobacterium smegmatis mc(2) 155, Mycobacterium avium DSM 44156 and DSM 44157. Cytotoxic effect was evaluated against human macrophages from the monocytic THP-1 cells. Main classes of compounds in these active extracts were proposed from their (1)H NMR spectroscopic characterizations.
n-Hexane extracts of Maerua edulis and Securidaca longepedunculata, ethyl acetate extract of Tabernaemontana elegans and dichloromethane extract of Zanthoxylum capense were found to possess considerable activity against Mycobacterium bovis BCG and Mycobacterium tuberculosis H37Ra with MIC 15.6-62.5 μg/mL. Tabernaemontana elegans ethyl acetate extract displayed strong activity against Mycobacterium tuberculosis H37Rv (MIC 15.6 μg/mL). Except for Tabernaemontana elegans ethyl acetate extract which presented potent cytotoxic effects in THP-1 cells (IC(50)<4 μg/mL), the other three plant extracts showed moderate to none toxicity. Based on (1)H NMR spectroscopic analysis, major components in both Maerua edulis and Securidaca longepedunculata n-hexane extracts were linear chain unsaturated fatty acids. Zanthoxylum capense dichloromethane extract contained more complex constituents (mostly phenolic compounds). In the most potent extract, Tabernaemontana elegans ethyl acetate extract, the prominent compounds were identified as indole alkaloids.
The pronounced antimycobacterial activity of the medicinal plants Maerua edulis, Securidaca longepedunculata, Zanthoxylum capense, and Tabernaemontana elegans suggested that they might provide compounds which could be potential anti-TB drug leads.
几种药用植物在莫桑比克传统上用于治疗肺结核和相关症状。
旨在评估 15 种药用植物的粗提取物的体外抗分枝杆菌活性，并揭示可能导致提取物活性的主要化合物类。
植物材料依次用正己烷、二氯甲烷、乙酸乙酯和 70%乙醇提取。根据传统用途，还制备了每种植物材料的煎煮液。肉汤微量稀释法用于筛选两种分枝杆菌种：耻垢分枝杆菌 ATCC 607 和结核分枝杆菌 H37Rv。MIC 低于 125 μg/mL 的提取物被认为是活性的，并进一步针对不同的分枝杆菌种和菌株进行测试，即结核分枝杆菌 H37Ra、牛分枝杆菌卡介苗 ATCC 35734、耻垢分枝杆菌 mc(2)155、鸟分枝杆菌 DSM 44156 和 DSM 44157。通过单核 THP-1 细胞中的人巨噬细胞评估细胞毒性作用。从这些活性提取物的 (1)H NMR 光谱特征中提出了主要化合物类。
Maerua edulis 和 Securidaca longepedunculata 的正己烷提取物、Tabernaemontana elegans 的乙酸乙酯提取物和 Zanthoxylum capense 的二氯甲烷提取物对牛分枝杆菌卡介苗和结核分枝杆菌 H37Ra 具有相当的活性，MIC 为 15.6-62.5 μg/mL。Tabernaemontana elegans 乙酸乙酯提取物对结核分枝杆菌 H37Rv 表现出很强的活性（MIC 为 15.6 μg/mL）。除了 Tabernaemontana elegans 乙酸乙酯提取物在 THP-1 细胞中呈现出很强的细胞毒性作用（IC(50)<4 μg/mL）外，其他三种植物提取物显示出中度至无毒性。基于 (1)H NMR 光谱分析，Maerua edulis 和 Securidaca longepedunculata 正己烷提取物的主要成分是线性不饱和脂肪酸。Zanthoxylum capense 二氯甲烷提取物含有更复杂的成分（主要是酚类化合物）。在最有效的提取物中，Tabernaemontana elegans 乙酸乙酯提取物中的突出化合物被鉴定为吲哚生物碱。
药用植物 Maerua edulis、Securidaca longepedunculata、Zanthoxylum capense 和 Tabernaemontana elegans 的明显抗分枝杆菌活性表明，它们可能提供潜在的抗结核药物先导化合物。
