Palm kernel cake as substrate for ß-Mannanase production by Bacillus subtilis ATCC3366 under submerged and solid state fermentations

Abstract

Beta-Mannanase activity and growth profile of Bacillus subtilis ATCC3366 during submerged fermentation (SmF) and solid state fermentation (SSF) using palm kernel cake as substrate were examined in this study. After 36 h of fermentation, ß-Mannanase produced by Bacillus subtilis in SmF system was recorded at 8 U/ml, whereas in SSF system was 230 U/g dry PKC. In SmF system, a long lag phase of 28 h were observed before the number of viable cells reached the maximum of 2.08 × 108 CFU/ml at 36 h; whereas in SSF system was 3.75 × 109 CFU/ml at 24 h, with no lag phase observed. Optimum conditions of enzyme activity were also examined. The optimum pH was 7.0, and optimum temperature was 55oC.