Conversion of hydrolysates of corn cobs and hulls into ethanol by recombinantEscherichia coli B containing integrated genes for ethanol production
- Cite this article as:
- Belll, D.S., Ingram, L.O., Ben-Bassat, A. et al. Biotechnol Lett (1992) 14: 857. doi:10.1007/BF01029153
Hemicellulose and residual starch in corn hulls from wet milling and hemicellulose in corn cobs were hydrolyzed by incubation in dilute sulfuric acid at 140°C to 160°C. These hydrolysates were efficiently fermented to ethanol by a genetically engineered derivative ofE. coli B, strain KO11. Fermentation of com hull hydrolysate was complete after 48 h with a final ethanol concentration of 38 grams per liter. Fermentation of corn cob hydrolysate was essentially complete after 24 h due to a lower concentration of sugars and higher levels of inocula. In both cases, ethanol produced was equivalent to 100% of the maximum theoretical yield (0.51 grams ethanol/gram sugar) based on momoner sugar content. ThusE. coli B strain KO11 appears to be an excellent candidate for the efficient production of ethanol from hydrolysates of corn residues.