Journal of Microbial & Biochemical Technology

Efficiency of modified basal medium for the differential and selective growth potential of Salmonella and Shigella species

Joint Event on 4^th World Congress and Expo on Applied Microbiology & 2^nd International Conference on Food Microbiology

November 29-December 01, 2017 Madrid, Spain

Muhammad Umar Sultan

University of Agriculture, Faisalabad, Pakistan

Posters & Accepted Abstracts: J Microb Biochem Technol

Abstract:

Various growth media have been designed for the growth of Salmonella and Shigella species. However a strict media is the need of the hour that will be purely selective and differential for these bacilli. The current study was conducted to evaluate the efficacy of some modifications in a basal medium that makes this medium selective and differential for the growth of Salmonella and Shigella species. The basic principle for making the media selective and differential depends upon the addition or deletion of some oils, plant extracts, sugars, amino acids and different salts. The concentration of bile salt, dyes, magnesium chloride (MgCl2) and sodium deoxycholate was adjusted to a point, that the media not only supported the growth of these pathogens, but also inhibit the growth of other Gram positive and Gram negative bacteria. Brilliant green and basic fuchsin was used that inhibit the growth of other Gram positive bacteria and Gram negative bacteria like coliforms. Out of the two modifications, the first modification had no MgCl2 and sodium deoxycholate, but had high concentration of dyes. The second modification had 4% MgCl2 and 0.25% sodium deoxycholate. First composition of media was unable to inhibit the growth of E. coli and some other coliforms. However, the second composition successfully inhibited the growth of other enterobactericeae members and Gram positive pathogens. After this modification, colonies of Salmonella and Shigella were visible on the modified media exhibiting specific macroscopic and microscopic characteristics. So this media selectively differentiates Salmonella and Shigella species from other pathogens and is very convenient for their isolation.