STUDIES ON HEAVY METAL TOLERANCE AND ANTIBIOTIC RESISTANCE PATTERNS OF BACTERIAL POPULATION ISOLATED FROM EFFLUENT TREATED WATER OF DELHI

Abstract

Along with the growing industrialization, problem of toxic heavy metal contamination is increasing worldwide. Microbes related technologies may provide an alternative or addition to conventional method of metal removal or metal recovery. The present study dealt with isolation, identification and characterization of microorganisms showing tolerance towards several heavy metals and resistance against antibiotics. These bacterial strains were isolated from different effluent treatment plants located in suburb of Delhi. Initially samples were analyzed for the presence of B.cereus, P.aeruginosa, E. coli & S.aureus through biochemical and morphological methods. Primary screening methods were applied to isolate heavy metals (viz. lead, zinc and cadmium) resistant organisms. Further susceptibility patterns of these isolates were studied towards clinically significant antibiotics such as meropenem, Doxycycline, streptomycin, tetracycline, gentamycin, cloxacillin, amoxicillin, ampicillin, vancomycin, and cephalosporin. All isolates were found to have 100% susceptibility against cadmium & 100% resistance against lead except P.aeruginosa (67%). Doxycycline was found to be most inert antibiotic as it was ineffective against all isolates, whereas meropenem was found to be most promising antibiotic followed by cephalosporin, streptomycin, tetracycline, and gentamycin. These heavy metal resistant organisms could be a potential agent for bioremediation of heavy metals polluted environment.

Keywords: Heavy metals, Effluent treatment water, Antibiotics, Susceptibility, Resistance, Bioremediation.