Reframing biorefinery processing chain of corn fiber for cellulosic ethanol production

Corn fiber is a byproduct of wet milling of corn grains with high hemicellulose content. Hemicellulose is only partially hydrolyzed in acid pretreatment and the complete hydrolysis occurs in the subsequent enzymatic hydrolysis. In the regular biorefinery chain of lignocellulose, the detoxification of toxic inhibitors is conducted immediately after pretreatment. When this process arrangement applies to corn fiber, acetic acid is accumulated to high level because of acetyl group release from residual hemicellulose. This study re-framed the biorefinery chain by conducting enzymatic hydrolysis before biodetoxification to completely release acetic acid from hemicellulose in corn fiber. Then the biodetoxification was followed immediately to degrade acetic acid, furfural and 5-hydroxymethylfurfural with the minimum loss of glucose and xylose. The improved ethanol production (70.2 g/L, or 8.9 % by v/v) was obtained by the re-framed chain of corn fiber biorefining. This study provided a practical approach for utilization of corn fiber for biofuel production.

Automated summary

This study reframed the biorefinery chain by conducting enzymatic hydrolysis before biodetoxification to improve the efficiency of corn fiber biorefining, ultimately achieving higher ethanol production.