Process optimisation for the biosynthesis of cellulase by Bacillus PC-BC6 and its mutant derivative Bacillus N3 using submerged fermentation.

This study deals with optimisation of cultural conditions for enhanced production of cellulase by Bacillus PC-BC6 and its mutant derivative Bacillus N3. Influence of different variables including incubation time, temperature, inoculum size, pH, nitrogen sources and metal ions has been studied. The optimum conditions for cellulase production were incubation period of 72 h, inoculum size 4% incubation temperature 37°C, pH 7, 0.25% ammonium sulphate, 0.2% peptone as inorganic and organic nitrogen source in case of Bacillus PC-BC6. In case of mutant Bacillus N3, optimal conditions were incubation period of 48 h, incubation temperature 37°C, inoculum size 3%, pH 7, 0.2% ammonium chloride and 0.15% yeast extract. Presence of MnSO4 and CaCl2 enhances the enzyme production by Bacillus PC-BC6 and mutant Bacillus N3, respectively. This study was innovative and successful in producing cellulase economically by using cheap indigenous substrate Saccharum spontaneum.

Random mutagenesis and media optimisation for hyperproduction of cellulase from Bacillus species using proximally analysed Saccharum spontaneum in submerged fermentation.

This study deals with the isolation of novel mutant of Bacillus and optimisation of media for the hyperproduction of cellulase. Cellulase-producing Bacillus PC-BC6 was subjected to physical and chemical mutagenesis to enhance the cellulolytic potential. Later, mutagenesis isolates were screened both qualitatively and quantitatively. Among all the tested isolates, Bacillus N3 yielded maximum (CMCase 1250 IU/mL/min and FPase 629 IU/mL/min) activity. The Bacillus N3 strain exhibited 1.7-fold more enzyme production as compared with the parental strain. Proximate analysis of untreated and pretreated Saccharum spontaneum was carried out to improve cellulase production. Three different media were tested for the production of cellulase, among which M2 medium containing MgSO4, pretreated S. spontaneum, K2HPO4, (NH4)2SO4 and peptone was found to be the best for maximum enzyme production by mutant Bacillus N3.