Production of fumaric acid from raw starchy materials by Rhizopus oryzae with SSF

To reduce the manufacturing cost of fumaric acid production by fermentation, four kinds of raw starchy materials were investigated, cassava powder, corn powder, degermed corn powder and starch. By comparing the nitrogen contents in them, carbon/nitrogen ratio of raw materials was the key factor affecting the fumaric acid production by Rhizopus oryzae. Based on this point, degermed corn powder was selected as the best raw starchy material for fumaric acid production. In addition, the simultaneous saccharification and fermentation (SSF) process for fumaric acid production was optimized. With degermed corn powder as substrate at 100 g/L total sugar concentration, the fumaric acid production (35.51 g/L), yield (0.355 g/g) and productivity (0.493 [g/(L·h)]) were obtained via SSF process in a 7-L fermentor.