Vol.8, No.1, 2020, pp.79-88, doi:10.32604/jrm.2020.08761
OPEN ACCESS
RESEARCH ARTICLE
Mannonic Acid and Bio-Ethanol Production from Konjac Using a Two-Step Bioprocess with Candida Shehatae and Gluconobacter Oxydans
  • Jianglin Zhao1, Xiaotong Zhang1, Weiwei Lei1, Xingqi Ji1, Xin Zhou1,2,*, Yong Xu1,2
1 College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
2 Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, China
* Corresponding Author: Xin Zhou. Email: xinzhou@njfu.edu.cn
Received 05 October 2019; Accepted 25 October 2019; Issue published 01 January 2020
Abstract
Amorphophallus konjac is rich in glucomannan, which can be hydrolyzed into glucose and mannose, thereby acting as an economic raw material for the acquisition of glucose and mannose. The total sugar yield was 91.2% when konjac powder was treated with 0.75% hydrochloric acid at 121°C for 1 h. Thus, dilute acid hydrolysates of konjac powder were used as a carbon source for obtaining value-added products. Here we showed that the microbial production of ethanol and mannonic acid was obtained by employing Candida shehatae (C. shehatae) and Gluconobacter oxydans (G. oxydans). Through a step-by-step bioprocess, glucose is the first selectively converted to ethanol by C. shehatae, which enables G. oxydans-mediated biocatalysis of mannose to mannonic acid. Finally, approximately 100 g ethanol and 340 g mannonic acid were produced starting from 1 kg refined konjac powder. The results demonstrated the feasibility of this bioconversion method for producing mannonic acid starting from crude hydrolysates of konjac powder.
Keywords
Konjac; mannonic acid; ethanol; Gluconobacter oxydans; Candida shehatae
Cite This Article
Zhao, J., Zhang, X., Lei, W., Ji, X., Zhou, X., et al. (2020). Mannonic Acid and Bio-Ethanol Production from Konjac Using a Two-Step Bioprocess with Candida Shehatae and Gluconobacter Oxydans. Journal of Renewable Materials, 8(1), 79–88.