Production and characterization of cellulase from the newly isolated Bacillus subtilis A8 on rice bran and corncob

Abstract Rice bran and corncob are the agricultural waste with the high cellulose content. The research was carried out to utilize rice bran and corncob as media/substrate to produce cellulase enzyme by means of the bacteria fermentation process. Bacteria that used to the fermentation process isolated from the shrimp paste origin Bonang, Samarinda, East Kalimantan. Bacteria identified molecularly based on 16S rDNA sequence. The results of identification showed the bacteria is Bacillus subtilis A8. In the research showed the cellulase enzyme activity of B. subtilis A8 on the rice bran media have optimum of incubation time 3 days at pH 6.0 and temperature 60°C, activated by Na+, Co+2, Cu+2, Mg+2, and Zn+2 ions and the protein content 0.13 μg/mL. The cellulase enzyme activity of B. subtilis A8 on the corncob media have optimum of incubation time 3 days at pH 7.0 and temperature 50°C and activated by Na+ and Co+2, whereas Cu+2, Mg+2, and Zn+2 are inhibitor and the protein content 0.04 μg/mL.