Evaluation of antimicrobial activities of myxobacteria extracts

Abstract

    The antimicrobial effects of the total extracts on VY/3 medium of 43 myxobacteria isolates in Vietnam were screened on 5 bacterial strains: MSSA, MRSA, S. faecalis, E. coli, P. aeruginosa, 5 fungal strains of A. niger, Penicillium sp., Mucor sp., Rhizopus sp., and C. albicans using the agar well diffusion assay. There were 41/43 (95.3 %) samples showing activities against at least one test microorganism, with higher activities against filamentous fungi (ranging from (48.8-69.8) % in 4 fungal strains) than against bacteria, and the ability to inhibit Gram-positive bacteria better than Gram-negative. Two strains NC02, NC11 (belonging to genus Myxococcus), which showed high inhibitory capacity, were determined the minimum inhibitory concentration (MIC) values via microdilution on 96-well microtiter plate. The MIC value of NC02 was impressive with (32 and 4) µg/mL for MRSA and A. niger. The MIC value of strain NC11 was 32 µg/mL, which inhibited both C. albicans and A. niger. These two potential isolates can be used in further studies to identify the active components in the total extract.