ISOLATION AND IDENTIFICATION OF ANTI-MRSA COMPOUND FROM TERRESTRIAL ACTINOMYCETES SPECIES VITBKA3

Abstract

Drug resistant pathogens are a major threat to human health and well-being. Methicillin resistant Staphylococcus aureus infection and their resistance to third generation antibiotics are increasing worldwide. Screening of tterrestrial actinomycetes isolate VITBKA3 for anti-MRSA activity showed 20mm zone of inhibition against MRSA strain (ATCC 43300). The potential isolate was subjected to morphological, biochemical and molecular taxonomic characterization and identified as Streptomyces species. Molecular taxonomy and phylogenic studies showed that the isolate was similar to Streptomyces ganicidicus sp. and hence designated as Streptomyces ganicidicus sp. VITBKA3. Submerged fermentation followed by preparation of ethyl acetate extract and bioactivity guided purification of the active compound by silica gel column chromatography and characterization by FT-IR, NMR and GC-MS yielded an aromatic anhydrous compound. The structure of the pure compound was identified as 2-amino-3-phenylpropanoic (E)-3-cyclohexyl-2-methylacrylic anhydride (APCMA) having the chemical formula of C₁₉H₂₅NO₃ and the molecular weight of 315.18 g/mol. The lead compound showed 18mm zone of inhibition against MRSA strain with the MIC value of 6.25 µ/ml. The outcome of this study suggests that the lead compound APCMA from Streptomyces ganicidicus sp. VITBKA3 can effectively inhibit MRSA strain.