Production of potent antimicrobial agent by actinomycete, Streptomyces sannanensis strain SU118 isolated from phoomdi in Loktak Lake of Manipur, India

Abstract

BackgroundActinomycetes have provided a wealth of bioactive secondary metabolites with interesting activities such as antimicrobial, antiviral and anticancer. The study aims at isolation, characterization and the antimicrobial potentiality of Streptomyces sannanensis SU118 obtained from Phoomdi, a unique habitat of Loktak Lake of Manipur, India.ResultsAn actinomycete strain isolated from Phoomdi soil of Loktak Lake of Manipur, India was identified as Streptomyces sannanensis SU118. It is a Gram-positive filamentous bacterium which exhibits antimicrobial activity only against Gram-positive bacteria, while Gram-negative organisms were not affected. Glucose Soyabean meal broth was found to be the suitable medium for antibiotic production at 28°C for seven days of incubation. The antimicrobial agent produced by the strain was extracted with ethyl acetate as solvent and purified by thin layer chromatography. Screening and bioassay - guided fractionation of the ethyl acetate extract from the culture filtrate led to the isolation of an active potential compound (Rf value 0.56) with λmax 275.0 nm which has got the lowest minimum inhibitory concentration (0.5 μg/ml) against Staphylococcus aureus MTCC 96 and Staphylococcus aureus (clinical isolate), whereas highest (3.0 μg/ml) was recorded against Mycobacterium smegmatis MTCC 6 and Bacillus circulans MTCC 8074.ConclusionThis study has therefore uncovered the potential of exploring virgin untapped habitats in the Indo-Burma biodiversity hot spot region as reservoir of promising antimicrobial metabolite producer. These results highlighted the scope for further characterization of the metabolite and could be a candidate in the generation of new antimicrobial agents.

Statistical Modelling and Optimization of Fermentation Medium for Lincomycin Production by Streptomyces lincolnensis Immobilized Cells

“…Carbon source, like simple sugar in fermentation media enhanced growth as well as bioactive metabolite production rather than more complex carbons. Other finding revealed that the production of antibiotic by S. tanashiensis A2D was preferred in media containing soyabean meal as carbon source 20 . In view of significance of media components, soluble starch and dextrin as carbon sources, malt extract and (NH 4 ) 2 SO 4 as organic and inorganic nitrogen source respectively were chosen as most significant ingredients in the fermentation medium for lincomycin production.…”

Molecular Identification, Isolation and Evaluation of Persian Gulf Actinomycetes as Candidates of Cytotoxic Metabolites Against Breast Cancer

“…The organic phase, containing antibiotic compounds, was isolated by a decanter and condensed by heat. The extracted metabolites were used to investigate the anti-cancer activity of the isolates on the breast cancer cell line [11,12]. …”

Chromatography-Based Partial Purification and Characterization of Antimicrobial Compound Isolated From a Terrestrial Streptomyces

“…Filamentous actinomycetes are known to have the ability to produce a wide variety of secondary metabolites [3,4], many of which have useful applications in human and veterinary medicine and agriculture [5], such as enzyme immuno-modulators, antibiotics, insecticides, herbicides, and anticancer agents [6]. Among Actinomycetes, Streptomyces which has long been recognized as a major source of bioactive molecules covers around 70% of the total antibiotic products [7,8]. This genus was confirmed to be promising bacteria against several pathogens and is well known for their potential to produce a large number of inhibitory metabolites used in industry and pharmacy [9].…”