Capacity of Auricularia auricula-judae to degrade agro-forestry residues

Abstract

Agro-forestry residues are a widespread lignocellulosic biomass, which could be used as raw material in many industries. The essential precondition for their usage is delignification, a process where white-rot fungi have a crucial role due to their powerful ligninolytic enzyme system. The objectives of this study were to investigate the insufficiently studied ligninolytic potential of Auricularia auricula-judae by determining its Mn-oxidizing peroxidase and laccase activities, as well as its capacity for lignin, hemicellulose and cellulose degradation during fermentation of common agro-forestry residues. The highest Mn-dependent and Mn-independent peroxidase activities were detected after plum sawdust and wheat straw solid-state fermentation (121.21 U L-1 and 136.36 U L-1, respectively), while only blackberry sawdust induced laccase production (107.37 U L-1). A significant reduction in the lignin content (46.4%) was achieved after wheat straw fermentation, while the highest selectivity index (12.71) was observed for oak sawdust. These data show that A. auricula-judae has a great potential to delignify plant residues and, consequently, can be used in various biotechnological processes.