Status of filamentous fungi in integrated biorefineries

Biorefinery operations may be made more cost competitive through use of cheaper feedstocks (e.g. lignocellulosic wastes) and integration of multiple revenue streams. Current methods for converting lignocellulosics into valuable products are inefficient and expensive due to the complexity of the feedstock. By looking to nature, however, these expensive and complex processes may be consolidated into a simple, cheap, and environmentally benign process. The findings of this review demonstrate that the diversity of filamentous fungi is such that each step of the biorefining process may be catalyzed by a number of different species. While no single microorganism may catalyze all the process steps, by combining certain strains and targeting multiple products, the complete valorization of biomass may be achieved. This review describes in detail the variety of valuable chemical products that filamentous fungi produce, the variety of substrates used to produce these chemicals, and methods for maximizing production. The technical and economic findings herein demonstrate the means by which a successful integrated biorefinery model may be devised using filamentous fungi.