Production of Lignocellulolytic Enzymes by Mushrooms

Biopolymers contained within or derived from plant biomass form by far the largest pool of soil carbon. The decomposition of lignocellulose in the soil environment thus attracts considerable attention. Lignocellulose is composed mainly of the polysaccharidic polymers cellulose and hemicelluloses, and the polyphenolic polymer lignin. During transformation in soils, humic substances (humus, humic and fulvic acids) are formed from both lignocellulose and structural components of microbial decomposers. This is achieved through the concerted action of lignocellulose-degrading enzymes, whose activity is regulated by soil properties, land use and the identity of their microbial producers. Soil fungi seem to be the most important players in lignocellulose transformation processes due to their ability to attack both polysaccharides and polyphenols in the soil organic matter. While some basic concepts of regulation of enzymatic activity have been outlined, questions regarding enzyme production and diversity at the molecular level are just recently being addressed. Moreover, current results show that the ability to decompose lignin and cellulose is not restricted to saprotrophic basidiomycetes and ascomycetes but that the contribution of ectomycorrhizal fungi can be important. From a practical viewpoint, the ability to produce lignocellulose-decomposing enzymes by mushrooms is important for their cultivation, efficient substrate use, high yield and production of valueadded products from lignocellulosic agrowastes.