Amylase Production on Solid State Fermentation by Bacillus Spp

Abstract

Twenty bacterial isolates were isolated from different sources. Preliminary screening for amylotic bacteria was performed on starch solid media. Out of them; 11 isolates showed positive results when flooded with iodine solution. The amylotic activity index was 93, 95 and 99. Identification of all isolates revealed that they belonged to the genus Bacillus. Out of all, three strains of Bacillus designated as B1, B2, and B11 were chosen for further study; according to their saccharification activity measured with the DNS method. Optimum conditions for enzyme production were measured, using wheat bran solid state fermentation (SSF) method. The optimum conditions for the three strains were generally found to be 55%- 75% moisture contents ; not less than 48 hrs incubation time (72 hours max. ); maximum enzymes production was attained at incubation temperature of 30℃ - 50℃; although the amylase retained more than 89% of its activity at temperature ranging from20℃ -70℃ , and optimum pH of 3.5.Qualitative analysis revealed that glucose and maltose was produced by Bacillus strains, B11 enzymes from hydrolysis of soluble starch.