摘要
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℃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.
基金
the financial support from the National Natural Science Foundation of China(31901270)
the Scientific Research Start-up Funds of Nanjing Forestry University,China(163030127).
