Senthil-Rajan D, Rajkumar M, Srinivasan R, Kumarappan C, Arunkumar K, Senthilkumar K L, Srikanth M V
School of Pharmacy, International Medical University, Bukit Jalil, Kuala Lumpur, Malaysia.
Department of Pharmacognosy, Padmavathi College of Pharmacy and Research Institute, Tamilnadu, India.
Trop Biomed. 2013 Dec;30(4):570-8.
Many medicinal plants have been used for centuries in daily life to treat microbial diseases all over the world. In this study, the in vitro antibacterial activity of aqueous and ethanol root extracts of Thespesia populnea Linn were investigated. Antimicrobial properties of T. populnea Linn was evaluated against five pathogenic bacteria and two fungi. Disc diffusion method and minimum inhibitory concentration (MIC) were determined by broth serial dilution method. The ciprofloxacin (5 μg/ml) and flucanozole (100 units/disc) were used as positive controls for bacteria and fungi respectively. Different concentrations (50, 100, 150 μg/ml) of ethanolic and aqueous root extracts of T. populnea were checked for the dose dependent antibacterial activity. Thespesia populnea showed broad spectrum antimicrobial activity against gram positive and gram negative bacteria and maximum inhibition by ethanolic extract was observed at higher dose (250 μg/ml) as 27±0.2mm. The MIC of the ethanol extract was 10 μg/ml for Staphylococcus aureus and 750 μg/ml for Candida albicans. The antifungal activity offered against S. aureus by the ethanolic extract is more than the aqueous extract. The results concluded that the anti-microbial activity of T. populnea was dose dependent. As the concentration increased the inhibition zone also increased. Flavonoids and tannins present in the extracts may be responsible for the antimicrobial activity.
几个世纪以来，许多药用植物在世界各地的日常生活中被用于治疗微生物疾病。在本研究中，对杨叶肖槿根的水提取物和乙醇提取物的体外抗菌活性进行了研究。评估了杨叶肖槿对五种病原菌和两种真菌的抗菌性能。采用纸片扩散法，通过肉汤系列稀释法测定最低抑菌浓度（MIC）。分别以环丙沙星（5μg/ml）和氟康唑（100单位/片）作为细菌和真菌的阳性对照。检测了杨叶肖槿根乙醇提取物和水提取物不同浓度（50、100、150μg/ml）的剂量依赖性抗菌活性。杨叶肖槿对革兰氏阳性菌和革兰氏阴性菌均表现出广谱抗菌活性，在较高剂量（250μg/ml）时，乙醇提取物的抑菌圈最大，为27±0.2mm。乙醇提取物对金黄色葡萄球菌的MIC为10μg/ml，对白色念珠菌的MIC为750μg/ml。乙醇提取物对金黄色葡萄球菌的抗真菌活性高于水提取物。结果表明，杨叶肖槿的抗菌活性具有剂量依赖性。随着浓度的增加，抑菌圈也增大。提取物中存在的黄酮类化合物和单宁可能是抗菌活性的原因。
