Direct conversion from cassava to bioethanol with a recombinant strain of yeast

作者：Liu Ze Huan^*; Zheng Yang Yang; Gong Ying Xue; Li Jing Bo; Xiao Wen Juan; Lin Jiang Hai

来源：Journal of Shenzhen University Science and Engineering, 2012, 29(6): 548-552.

DOI：10.3724/SP.J.1249.2012.06548

• Cassava
• Co-expression
• Culture supernatant
• Direct conversion
• Efficient process
• Electroporation
• Ethanol concentrations
• Ethanol fermentation
• Glucoamylase
• Industrial processs
• Recombinant strains
• Recombinant yeast
• Theoretical values

In order to develop a direct and efficient process to produce ethanol from starchy materials cassava, a recombinant strain of industrial polyploid yeast co-expressing α-amylase and glucoamylase genes was constructed. The two genes were cloned into the co-expression vector pScIKP, and then transformed into Saccharomyces cerevisiae AS2.489 by electroporation. Activities of α-amylase and glucoamylase in the culture supernatant of the recombinant strain S. cerevisiae-AG reached 1940 U/mL and 15.5 U/mL respectively. Ethanol fermentation was also conducted using a protocol simulating the industrial process in a 5 L jar fermenter with 200 g/L of cassava. The ethanol concentration rate φ(ethanol)=8.68%, i.e. 80.9% of equivalent theoretical value. This result indicates that our recombinant yeast is sufficiently robust and capable of producing ethanol directly from cassava without the addition of any commercial amylases.

• 出版日期2012-11
• 单位暨南大学