Research Centre for Plant Growth and Development, School of Life Sciences, University of KwaZulu-Natal Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa.
J Ethnopharmacol. 2012 Aug 30;143(1):185-93. doi: 10.1016/j.jep.2012.06.022. Epub 2012 Jun 23.
Several ailments are caused by infectious bacteria and in other diseases; they act as co-infection which complicate human life by causing health hazards. In Venda (South Africa), many plants are used in traditional medicine to treat cough and fever.
This study was aimed at evaluating the antibacterial and antifungal properties, cyclooxygenases (COX), acetylcholinesterase (AChE) enzyme inhibitory effects and the phenolic composition as well as mutagenic properties of six medicinal plants used by the Venda people of Limpopo Province of South Africa against cough and fever.
The petroleum ether (PE), dichloromethane (DCM), 80% ethanol (EtOH) and water extracts of six plants were tested against four infectious bacteria (Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus) and a fungus Candida albicans. The same extracts were evaluated for their ability to inhibit COX-1 and -2 enzymes. Methanolic and water extracts of the same plant were tested for acetylcholinesterase inhibitory effects. Total phenolics, flavonoids, gallotannins and condensed tannins were determined. The ability of the extracts to bind and precipitate proteins was also investigated. The extracts were investigated for genotoxicity with and without S9 (metabolic activation) against three Salmonella typhimurium tester strains TA98, TA100 and TA102.
The organic extracts of Rhus lancea leaves exhibited the best antibacterial activity with minimum inhibitory concentration (MIC) values ranging from 0.0061 to 0.049mg/ml. The best antifungal activity was observed from a DCM extract of Syzygium cordatum leaves with a MIC value of 0.195mg/ml. The methanolic and water extracts of the same plant exhibited high inhibitory effects towards AChE with IC(50) values of 0.22 and 0.26mg/ml, respectively. The highest levels of flavonoids and gallotannins were detected in Spirostachys africana bark; 11.57 and 48.88μg/g, respectively. The highest percentages (1.2%) of condensed tannins were detected in Uvaria caffra leaves. The high levels of phenolic compounds may have been responsible for high antimicrobial activities for extracts of S. africana bark and U. caffra leaves. S. cordatum leaves represented the highest affinity for protein binding with 93%. All the extracts were non-mutagenic towards the three tested strains with and without S9 metabolic activation.
The result obtained in this study goes a long way in validating the ethnobotanical usage of these medicinal plants in the treatment of cough and fever by the Venda people. However, more evidence obtainable from other assays not performed here are urgently required to confirm these results.
有几种疾病是由传染性细菌引起的，在其他疾病中，它们作为合并感染存在，通过造成健康危害而使人类生活复杂化。在南非文达（Venda），许多植物被用于传统医学中，以治疗咳嗽和发烧。
本研究旨在评估六种被南非林波波省文达人用于治疗咳嗽和发烧的药用植物的抗菌和抗真菌特性、环氧化酶（COX）、乙酰胆碱酯酶（AChE）抑制作用以及酚类成分和致突变特性。
用石油醚（PE）、二氯甲烷（DCM）、80%乙醇（EtOH）和水提取物对六种植物进行了测试，以评估其对四种传染性细菌（枯草芽孢杆菌、大肠杆菌、肺炎克雷伯菌和金黄色葡萄球菌）和一种真菌白色念珠菌的抑制作用。还评估了相同提取物抑制 COX-1 和 COX-2 酶的能力。对同一种植物的甲醇和水提取物进行了乙酰胆碱酯酶抑制作用的测试。还测定了总酚类、类黄酮、鞣花单宁和缩合单宁的含量。还研究了提取物与蛋白质结合和沉淀的能力。提取物未经 S9（代谢激活）和经 S9 处理后，用三种鼠伤寒沙门氏菌测试菌株 TA98、TA100 和 TA102 进行了致突变性测试。
柳兰叶的有机提取物表现出最好的抗菌活性，最低抑菌浓度（MIC）值在 0.0061 至 0.049mg/ml 之间。二氯甲烷提取物对 Syzygium cordatum 叶的抗真菌活性最好，MIC 值为 0.195mg/ml。同一植物的甲醇和水提取物对 AChE 具有很高的抑制作用，IC（50）值分别为 0.22 和 0.26mg/ml。在 Spirostachys africana 树皮中检测到最高水平的类黄酮和鞣花单宁，分别为 11.57 和 48.88μg/g。在 Uvaria caffra 叶中检测到最高百分比（1.2%）的缩合单宁。高含量的酚类化合物可能是 S. africana 树皮和 U. caffra 叶提取物具有高抗菌活性的原因。S. cordatum 叶对蛋白质的结合亲和力最高，为 93%。所有提取物在未经和经 S9 代谢激活的情况下，对三种测试菌株均无致突变性。
本研究的结果在很大程度上验证了这些药用植物在文达人治疗咳嗽和发烧方面的民族植物学用途。然而，迫切需要从其他未在此进行的检测中获得更多证据来证实这些结果。
