Comparative characterization of extracellular enzymes secreted by Phanerochaete chrysosporium during solid-state and submerged fermentation

Influence of water content on the expression of lignocellulolytic enzymes by Phanerochaete chrysosporium remains unclear. This work compares the enzyme production profiles of P. chrysosporium during solid-state and submerged fermentation. There were 110 and 64 extracellular carbohydrate-active enzymes identified in solid-state and submerged fermentation respectively, among which 57 enzymes were common to both of the secretomes. P. chrysosporium secreted more cellulases (especially lytic polysaccharide monooxygenase) and hemicellulases during solid-state fermentation while the proportion of enzyme containing carbohydrate-binding module was higher for submerged fermentation. Although its activities were weaker, the enzyme cocktail from submerged fermentation was surprisingly more effective in hydrolysis at low substrate loading. This advantage of enzymes from submerged fermentation was mainly attributed to carbohydrate-binding module because more xylanases bound with substrate at the beginning of hydrolysis. These results reveal the influence of fermentation conditions on enzyme produced by P. chrysosporium for the first time and show the importance of carbohydrate-binding module in the hydrolysis process of lignocellulose. (C) 2020 Published by Elsevier B.V.