Optimization of Cultural Conditions for the Over Production of Alkaline Protease from a Mutant Bacillus Licheniformis Bl8

Various factors influencing the alkaline protease production by mutant Bacillus licheniformis Bl8 were studied. The production was maximum when the culture was in the early stationary phase. The optimum temperature of incubation and the optimum initial pH requirement was 400C and pH 10.0 & 10.5 respectively. The incubation period required for the maximum accumulation of alkaline protease was 72h. The optimum level of inoculum of 10% was found to be favoring the production. The age of inoculum was found to be 24h for maximum protease productivity. Further increase in the age of inoculum was found to be having little (or) no effect on alkaline protease production. The best carbon source for the production was maltose and Yeast extract plus peptone was the best nitrogen sources. Casein was also found to increase the alkaline protease production. Effect of some other factors like vitamins, amino acids, trace elements, metabolic inhibitors, antibiotics, surfactants and agitation were studied. Among the various vitamins tested pyridoxine HCl was found to slightly stimulate the production whereas, other vitamins had little (or) no effect. Among the amino acids L-Tyrosine had shown the maximum increase. Among the all the trace elements tested, ammonium chloride augmented the maximum alkaline protease production. Different metabolic inhibitors viz., AgNo3, EDTA, NaF, KMnO4, -ME, PMSF and Idoacetate were studied for their effect on alkaline protease production by Bacillus licheniformis (Bl8). All the inhibitors were showed the inhibitory effect on the protease production. Significantly PMSF showed complete loss of production revealings that the type of protease in the present study belongs to
serine protease. And all the antibiotics tested were also showed inhibitory effect on alkaline protease production by the mutant Bl8 strain. This was also followed by the surfactants tested in this study. Agitation was found to be increasing the production significantly and the maximum yield observed at 150 rpm.