Screening of different media for sporulation of Bacillus megaterium

Abstract

Five different sporulation medium such as tryptone yeast extract (TYE) broth, tryptone glucose yeast extract (TGYE) broth, minimal media, Sucrose salt medium, Arret & Krishbaum (AK)sporulation agar were screened for spore production in Bacillus megaterium ATCC 9885. During this study, it was observed that out of different combinations of tryptone, yeast extract and dextrose sporulation was maximum (70%) in tryptone yeast extract broth. Effect of different salts on sporulation was studied by incorporation in TYE. It was observed that 41.7% sporulation in KCl followed by CaCl2.2H2O, FeSO4.7H2O, MgSO4.7H2Oand MnSO4.7H2Orespectively. Maximum sporulation (90 ± 0.6988%) was observed in AK sporulation agar with modified protocol followed by minimum sporulation in minimal medium and sucrose salt medium respectively. Spores and vegetative cells of ATCC 9885 was observed under Andor EMCCD (Electron Multiplying charge coupled device) camera showed that spores were arranged singly and small in size (2.8 ±0.2 μm 2 ) compared to vegetative cells that were in chains and larger in size (4.0 ±0.2 μm 2 ). Spores of Bacillus megaterium ATCC 9885 produced in A. K. Sporulation medium with modified protocol can be further utilized as bio-molecules for the development of bioassay for monitoring non-bacterial contaminants in milk (Aflatoxin M1).