Phytase production by Bacillus subtilis US417 in submerged and solid state fermentations

Abstract

When the variables (inoculum size, methanol and yeast extract) identified to affect phytase production by Bacillus subtilis US417 using Plackett-Burman design were optimized by RSM, a high enzyme production of 112 U/g of wheat bran was attained. Overall, a 5-fold improvement in phytase production was achieved. In SSF, on the other hand, a 4-fold enhancement in enzyme titer was attained (85 U/g of wheat bran). Based on these findings, phytase productivity was higher in SF [2.3 U/(g × h)] than in SSF [1.2 U/(g × h)].