Detection of bacteriocin like substances from normal skin microflora as alternative to conventional antibioti
Reazul Karim*, Nuruddin Mahmud, Mohammad Abdul Hakim
Department of Microbiology, University of Chittagong, Chittagong – 4331, Bangladesh
Abstract
Gradual increase of antibiotic resistance is a global problem. In this study, we have developed an alternative approach as an alternative to conventional antibiotics from the natural source to solve the antibiotic resistance problem. Some normal microflora were isolated from healthy human skin, their antimicrobial efficacy were examined against some skin and intestinal pathogens initially by cross streak method and finally by disc and well diffusion method. Two normal microflora (e.g., Bacillus licheniformis and Corynebacterium jeikeium) were observed producing antimicrobial metabolites which were effective against Klebsiella pneumoniae subsp. pneumoniae, with maximum antimicrobial activity at 250C, 48h, pH 9 and 370C, 72h, pH 7 respectively. Only the antimicrobial metabolites produced by Bacillus licheniformis was detected as bacteriocin like substances which was further confirmed as antimicrobial peptide through papain treatment. Efficacy of crude bacteriocin like substances was compared with 10 commercially available antibiotics against Klebsiella pneumoniae subsp. pneumoniae. Of these, 4 antibiotics were found resistant but crude bacteriocin like substances along with 6 other antibiotics showed remarkable susceptibility. Therefore, more studies on the efficacy of this bacteriocin like substances needs to be done to fully understand its mechanism and potentiality as novel antimicrobials.
Keywords: Antimicrobial metabolites, Bacteriocin, Antibiotic resistance, Normal microbiota
