Asian Journal of Microbiology, Biotechnology & Environmental Sciences Paper

Vol 21, Issue 4, 2019; Page No.(1041-1046)

ISOLATION, CHARACTERIZATION OF LACTIC ACID BACTERIA FROM COW AND BUFFALO MILK AND EVALUATION FOR ANTIBACTERIAL AND ANTIMYCOBACTERIAL ACTIVITY IN VITRO

REVATHY K., RADHAKRISHNAN MANIKKAM AND SIVARAJ ANBARASU

Abstract

Lactic Acid Bacteria (LAB) are the heterogeneous group of Gram positive bacteria exist in the forms of both cocci and bacilli. Members of the LAB grab - extensive research due to their potential applications in various food industries and Generally Recognized As Safe (GRAS) status. Animal milk is considered as one of the natural habitat of LAB which is known to be responsible for the natural fermentation of milk products. The bacterial count in raw milk accounts around 30% of LAB and it varies depends on animal species, season, production, etc. In our study, we have isolated 50 LAB isolates from fresh cow and buffalo milk using standard protocol with some modification and identified at their genus level as described by Hemangi et al. (2012). LAB isolated from cow and buffalo milk samples were belongs to the genus viz., Aerococcus (30%), Pediococcus (26%), Lactococcus (8%), Streptococcus (8%), Enterococcus (6%), Tetragenococcus (12%), Streptobacterium (6%) and Thermobacterium (4%). Antibacterial and antimycobacterial properties of all the isolates have been evaluated against S. aureus, B. cereus, E. coli, K. pneumoniae, M. smegmatis, M. fortuitum. Notably, the inhibitory activity of cell free supernatant (CFS) obtained from 10 LAB isolates out of 50 isolates showed significant antimycobacterial activity against M. smegmatis and M. fortuitum. Further extraction and purification of bacteriocin from potential LAB isolates can develop as a good candidate to fight against non-tuberculous mycobacteria.