Study on the Sugar-Producing Effect of High-Temperature Anaerobic Straw Biosaccharification Strain

Abstract

The utilization of straw waste cellulose will be beneficial by economic, social, and environmental means. The present study sought to screen the high-efficiency cellulose sugar-producing strain from corn straw. The 16S high-throughput sequencing method and the combination of morphological, physiological, and biochemical characteristics of the strain confirmed the strain to be Clostridium thermocellum, which was named Clostridium thermocellum FC811. Moreover, the single factor experiment was conducted to investigate the effect of environmental factors on saccharification efficiency. The optimal saccharification conditions of cellulose saccharification of FC811 strain selected through response surface analysis were as follows: temperature of 58.9 °C, pH of 7.21, culture time of 6.60 d, substrate concentration of 5.01 g/L, and yeast powder concentration of 2.15 g/L. The soluble sugar yield was 3.11 g/L, and the conversion rate of reducing sugar was 62.2%. This study will provide a reference for resource and energy utilization of straw materials, simultaneous fermentation of sugar and hydrogen production, and their large-scale production and application.