Co-production of hydrogen and ethanol by Thermoanaerobacterium thermosaccharolyticum KKU-ED1 from alpha-cellulose and cellulose fraction of sugarcane bagasse

Abstract

This research aims to evaluate the co-production of hydrogen and ethanol from lignocellulosic materials by Thermoanaerobacterium thermosaccharolyticum KKU-ED1. The optimum conditions for co-production of hydrogen and ethanol in batch fermentation was determined using alpha-cellulose as a basic model substrate to mimic the natural cellulose part of a lignocellulosic material. The optimal conditions attained were an initial pH of 7.0, a temperature of 55 °C, and a cellulose content of 20 g/L, which resulted in the maximum hydrogen production and ethanol (EtOH) yield of 6113 mL H2/L and 1.71 mmol EtOH/g-celluloseconsumed, respectively. The potential of the KKU-ED1 strain to produce hydrogen and ethanol from natural cellulose in sugarcane bagasse was further evaluated under the optimum conditions. Hydrogen production and ethanol yield of 218 mL H2/L, and 0.26 mmol EtOH/g-celluloseconsumed were obtained. Results indicated that the strain KKU-ED1 is a thermophilic cellulolytic bacterium capable of co-producing hydrogen and ethanol from lignocellulosic materials.