Multi-strategy in production of high titer gluconic acid by the fermentation of concentrated cellulosic hydrolysate with Gluconobacter oxydans
2022
Dai, Lin | Lian, Zhina | Zhang, Rui | Nawaz, Ali | ul Haq, Ikram | Zhou, Xin | Xu, Yong
Cellulosic hydrolysate from the hydrolysis of glucan-riched biomass can offer abundantly bioavailable glucose, which is an alternative feedstock for gluconic acid production. In order to speed up the process of cellulosic-based gluconic acid synthesis industrialization, cost reduction by using efficient substrate in batch-fermentation with high yield and productivity is extremely important. However, enriched glucose obtained by concentrating enzymatic hydrolysate inevitably ascends the viscosity, resulting in a lower oxygen transfer rate that cannot meet the requirement of bio-oxidation with Gluconobacter oxydans, resulting in gluconic acid productivity decreased drastically once the glucose content in the concentrated enzymatic hydrolysate was over 240g/L with corresponding viscosity over 4 mPa·s. In view of the above problems, a combined strategy of activated carbon treatment and high-tension oxygen supply was applied to improve efficiency. Finally, approximately 230g/L gluconic acid with 9.6g/L/h productivity was achieved, which enabled the industrial-scale gluconic acid bio-production from cellulosic materials.
显示更多 [+] 显示较少 [-]