BROAD SPECTRUM ANTIBIOFILM AND ANTIQUORUM SENSING POTENTIAL OF CRUDE SECONDARY METABOLITE EXTRACTS OF MICROBIAL ISOLATES OBTAINED FROM POLLUTED WALDHUNI RIVER

摘要

Bacterial biofilms due to antibacterial resistance are causing serious health issues with respect to infection control, its prognosis and treatment of disease. The current scenario demands need of new and alternative antibacterial compounds for treatment of such infections. The current study highlights the use of polluted river, Waldhuni, as a source of potent microorganisms with antibiofilm properties. 186 microorganisms were isolated from Waldhuni River, and tested for quorum sensing inhibitory activity (QSI) against C. violaceum MTCC 2656. Seven isolates exhibited QSI activity, out of which 1 isolate PB2 was selected for further study based on its high QSI potential. PB2 displayed broad spectrum antibiofilm activity against eight strains of biofilm forming pathogens. The effective minimum biofilm eradication concentration (MBEC) of crude extract of PB2 secondary metabolite (SME) was found to be 500ppm. The extract reduced exo-polysaccharide (EPS) by 94.16%, viability by 90% and biofilm density by 96% in 6h treatment. It also rendered to inhibit extracellular DNA of Streptococcus mutans MTCC497, Enterococcus faecalis MTCC 439 and Pseudomonas aeruginosa MTCC 2453. PB2 isolate was identified to be Pseudomonas aeruginosa. Thus, Pseudomonas aeruginosa PB2 with antiquorum sensing and broad spectrum biofilm inhibitory activity was isolated from highly polluted Waldhuni river.