School of Chemistry, University of Wollongong, Wollongong, NSW 2522, Australia.
J Ethnopharmacol. 2011 Sep 1;137(1):730-42. doi: 10.1016/j.jep.2011.06.032. Epub 2011 Jun 28.
As many as 229 medicinal plants have been currently used in the Bhutanese Traditional Medicine (BTM) as a chief ingredient of polyherbal formulations and these plants have been individually indicated for treating various types of infections including malaria, tumor, and microbial. We have focused our study only on seven species of these plants.
We aim to evaluate the antiplasmodial, antimicrobial, anti-Trypanosoma brucei rhodesiense and cytotoxicity activities of the seven medicinal plants of Bhutan selected using an ethno-directed bio-rational approach. This study creates a scientific basis for their use in the BTM and gives foundation for further phytochemical and biological evaluations which can result in the discovery of new drug lead compounds.
A three stage process was conducted which consisted of: (1) an assessment of a pharmacopoeia and a formulary book of the BTM for their mode of plant uses; (2) selecting 25 anti-infective medicinal plants based on the five established criteria, collecting them, and screening for their major classes of phytochemicals using appropriate test protocols; and (3) finally analyzing the crude extracts of the seven medicinal plants, using the standard test protocols, for their antiplasmodial, antimicrobial, anti-Trypanosoma brucei rhodesiense and cytotoxicity activities as directed by the ethnopharmacological uses of each plant.
Out of 25 medicinal plants screened for their major classes of phytochemicals, the majority contained tannins, alkaloids and flavonoids. Out of the seven plant species investigated for their biological activities, all seven of them exhibited mild antimicrobial properties, five plants gave significant in vitro antiplasmodial activities, two plants gave moderate anti-Trypanosoma brucei rhodesiense activity, and one plant showed mild cytotoxicity. Meconopsis simplicifolia showed the highest antiplasmodial activity with IC(50) values of 0.40 μg/ml against TM4/8.2 strain (a wild type chloroquine and antifolate sensitive strain) and 6.39 μg/ml against K1CB1 (multidrug resistant strain) strain. Significantly the extracts from this plant did not show any cytotoxicity.
These findings provide the scientific basis for the use of seven medicinal plants in the BTM for the treatment of malaria, microbial infections, infectious fevers, and the Trypanosoma brucei rhodesiense infection. The results also form a good preliminary basis for the prioritization of candidate plant species for further in-depth phytochemical and pharmacological investigations toward our quest to unearth lead antiparasitic, anticancer and antimicrobial compounds.
目前，多达 229 种药用植物被用于不丹传统医学（BTM）中，作为复方草药制剂的主要成分，这些植物已被单独用于治疗各种类型的感染，包括疟疾、肿瘤和微生物感染。我们仅关注这 7 种植物中的 7 种。
我们旨在使用基于民族定向的生物合理性方法，评估从 BTM 中选择的 7 种药用植物的抗疟原虫、抗菌、抗非洲锥虫和细胞毒性活性。这项研究为它们在 BTM 中的应用提供了科学依据，并为进一步的植物化学和生物学评估奠定了基础，这可能导致发现新的药物先导化合物。
进行了三个阶段的研究，包括：（1）评估 BTM 的药典和配方书，了解其植物使用模式；（2）根据五个既定标准选择 25 种抗感染药用植物，收集它们，并使用适当的测试方案筛选其主要类别的植物化学物质；（3）最后，根据每种植物的民族药理学用途，使用标准测试方案，分析这 7 种药用植物的粗提取物的抗疟原虫、抗菌、抗非洲锥虫和细胞毒性活性。
在所筛选的 25 种药用植物中，大多数植物含有单宁、生物碱和类黄酮。在所研究的 7 种植物物种中，所有 7 种植物都表现出温和的抗菌特性，5 种植物表现出显著的体外抗疟原虫活性，2 种植物表现出中度抗非洲锥虫活性，1 种植物表现出温和的细胞毒性。美丽绿绒蒿表现出最高的抗疟原虫活性，其 TM4/8.2 株（野生型氯喹和抗叶酸敏感株）的 IC50 值为 0.40 μg/ml，对 K1CB1（多药耐药株）株的 IC50 值为 6.39 μg/ml。值得注意的是，该植物提取物没有表现出任何细胞毒性。
这些发现为 BTM 中 7 种药用植物治疗疟疾、微生物感染、传染性发热和非洲锥虫感染提供了科学依据。这些结果也为优先选择候选植物物种进行进一步的深入植物化学和药理学研究奠定了良好的初步基础，以寻找潜在的抗寄生虫、抗癌和抗菌化合物。
