Parai Debaprasad, Islam Ekramul, Mitra Jayati, Mukherjee Samir Kumar
a Department of Microbiology, University of Kalyani, Kalyani 741235, India.
b Department of Pathology, Regional Institute of Ophthalmology, Kolkata 700073, India.
Can J Microbiol. 2017 Feb;63(2):169-178. doi: 10.1139/cjm-2016-0365. Epub 2016 Oct 24.
The goal of this study was to evaluate the antibiofilm and antimicrobial activities of Bacoside A, a formulation of phytochemicals from Bacopa monnieri, against Staphylococcus aureus and Pseudomonas aeruginosa, which are known to form biofilms as one of their virulence traits. The antimicrobial effects of Bacoside A were tested using the minimum inhibitory concentration and minimum bactericidal concentration assays. A cell membrane disruption assay was performed to find its possible target site. MTT assay, crystal violet assay, and microscopic studies were performed to assess the antibiofilm activity. Bacoside A showed antimicrobial activity against both test organisms in their planktonic and biofilm states. At a subminimum inhibitory concentration of 200 μg·mL, Bacoside A significantly removed ∼88%-93% of bacterial biofilm developed on microtiter plates. Biochemical and microscopic studies suggested that the eradication of biofilm might be due to the loss of extracellular polymeric substances and to a change in cell membrane integrity of the selected bacterial strains treated with Bacoside A. These results indicate that Bacoside A might be considered as an antimicrobial having the ability to disrupt biofilms. Thus, either alone or in combination with other therapeutics, Bacoside A could be useful to treat biofilm-related infections caused by opportunistic bacterial pathogens.
本研究的目的是评估来自假马齿苋的植物化学成分制剂Bacoside A对金黄色葡萄球菌和铜绿假单胞菌的抗生物膜和抗菌活性，这两种细菌都以形成生物膜作为其毒力特征之一。使用最低抑菌浓度和最低杀菌浓度测定法测试了Bacoside A的抗菌效果。进行细胞膜破坏试验以确定其可能的作用靶点。采用MTT法、结晶紫法和显微镜研究来评估抗生物膜活性。Bacoside A对两种受试细菌的浮游状态和生物膜状态均显示出抗菌活性。在200μg·mL的亚最低抑菌浓度下，Bacoside A能显著去除微量滴定板上形成的约88%-93%的细菌生物膜。生化和显微镜研究表明，生物膜的消除可能是由于细胞外聚合物的损失以及用Bacoside A处理的所选细菌菌株细胞膜完整性的改变。这些结果表明，Bacoside A可能被视为一种具有破坏生物膜能力的抗菌剂。因此，单独使用或与其他治疗方法联合使用，Bacoside A可能有助于治疗由机会性细菌病原体引起的生物膜相关感染。
