Effects of laccase on lignin depolymerization and enzymatic hydrolysis of ensiled corn stover

• DOI: 10.1016/j.biortech.2012.04.085
• Publication Date: 2012-04-30T16:22:26Z
• Authors: Qin Chen; Megan N. Marshall; Scott M. Geib; Ming Tien; Tom L. Richard
• Keywords: Trametes; Waste Products; Silage; Glycoside Hydrolases; Hydrolysis; Laccase; Lignin; Zea mays; 01 natural sciences; Gas Chromatography-Mass Spectrometry; Polymerization; Quaternary Ammonium Compounds; Cellulase; Carbohydrate Metabolism; Cellulose; 0105 earth and related environmental sciences

The aim of this study was to explore the synergies of laccase, a ligninolytic enzyme, with cellulose and hemicellulase amendments on ensiled corn stover. Molecular signals of lignin decomposition were observed by tetramethylammonium hydroxide thermochemolysis and gas chromatography-mass spectroscopy (TMAH-GC-MS) analysis. The significant findings suggest that ensilage might provide a platform for biological pretreatment. By partially hydrolyzing cellulose and hemicellulose into soluble sugars, ensilage facilitates laccase penetration into the lignocellulose complex to enhance lignin degradation. Downstream cellulose hydrolysis was improved 7% with increasing laccase loading rate. These results demonstrate the potential of enzymes, either directly amended or expressed by microbes during ensilage, to maximize utilization of corn stover for cellulosic biofuels and other downstream fermentations.