Manikkam Radhakrishnan, Venugopal Gopikrishnan, Subramaniam Balaji, Ramasamy Balagurunathan, Kumar Vanaja
Centre for Drug Discovery and Development, Sathyabama University, Chennai, Tamil Nadu 600 119, India.
Department of Microbiology, Periyar University, Salem, Tamil Nadu 636 011, India.
Int Sch Res Notices. 2014 Nov 9;2014:812974. doi: 10.1155/2014/812974. eCollection 2014.
Bioactive potential of actinomycetes isolated from certain less explored Indian ecosystems against Mycobacterium tuberculosis and other nonmycobacterial pathogens was investigated. Actinomycetes were isolated from the soil samples collected from desert, coffee plantation, rubber forest, and hill area and their cultural and micromorphological characteristics were studied. Crude extracts were prepared by agar surface fermentation and tested against M. tuberculosis isolates by luciferase reporter phage (LRP) assay at 100 µg/mL. Activity against nonmycobacterial pathogens was studied by agar plug method. Totally 54 purified cultures of actinomycetes including 43 Streptomyces and 11 non-Streptomyces were isolated. While screening for antitubercular activity, extracts of 39 actinomycetes showed activity against one or more M. tuberculosis isolates whereas 27 isolates exhibited antagonistic activity against nonmycobacterial pathogens. In particular crude extracts from sixteen actinomycete isolates inhibited all the three M. tuberculosis isolates tested. Findings of the present study concluded that less explored ecosystems investigated in this study are the potential resource for bioactive actinomycetes. Further purification and characterization of active molecule from the potential extracts will pave the way for determination of MIC, toxicity, and specificity studies.
对从印度某些较少被探索的生态系统中分离出的放线菌针对结核分枝杆菌和其他非结核分枝杆菌病原体的生物活性潜力进行了研究。从沙漠、咖啡种植园、橡胶林和山区采集的土壤样本中分离出放线菌，并研究了它们的培养和微观形态特征。通过琼脂表面发酵制备粗提物，并以100µg/mL的浓度通过荧光素酶报告噬菌体（LRP）测定法对结核分枝杆菌分离株进行测试。通过琼脂块法研究对非结核分枝杆菌病原体的活性。总共分离出54株纯化的放线菌培养物，包括43株链霉菌和11株非链霉菌。在筛选抗结核活性时，39株放线菌的提取物对一种或多种结核分枝杆菌分离株表现出活性，而27株分离株对非结核分枝杆菌病原体表现出拮抗活性。特别是，来自16株放线菌分离株的粗提物抑制了所有测试的三种结核分枝杆菌分离株。本研究结果得出结论，本研究中调查的较少被探索的生态系统是生物活性放线菌的潜在资源。从潜在提取物中进一步纯化和表征活性分子将为确定最低抑菌浓度、毒性和特异性研究铺平道路。
