Economical succinic acid production from cane molasses by Actinobacillus succinogenes.

In this work, production of succinic acid by Actinobacillus succinogenes CGMCC1593 using cane molasses as a low cost carbon source was developed. In anaerobic bottles fermentation, succinic acid concentration of 50.6+/-0.9 g l(-1) was attained at 60 h using an optimum medium containing molasses pretreated with sulfuric acid, resulting in a succinic acid yield of 79.5+/-1.1% and sugar utilization of 97.1+/-0.6%. When batch fermentation was carried out in a 5-l stirred bioreactor with pretreated molasses, 46.4 g l(-1) of succinic acid was attained at 48 h and faster cells growth was also observed. Fed batch fermentation was performed to minimize the substrate (sugar) inhibition effect, giving 55.2 g l(-1) of succinic acid and 1.15 g l(-1)h(-1) of productivity at 48 h. The present study suggests that the inexpensive cane molasses could be utilized for the economical and efficient production of succinic acid by A. succinogenes.