Renewable mycelium based composite – sustainable approach for lignocellulose waste recovery and alternative to synthetic materials – a review
Galena Angelova, Mariya Brazkova, Albert Krastanov
Abstract
Abstract The agricultural waste with lignocellulose origin is considered to be one of the major environmental pollutants which, because of their high nutritional value, represent an extremely rich resource with significant potential for the production of value added bio-products. This review discusses the applications of higher fungi to upcycle abundant agricultural by-products into more sustainable materials and to promote the transition to a circular economy. It focuses on the main factors influencing the properties and application of mycelium composites – the feedstock, the basidiomycete species and their interaction with the feedstock. During controlled solid state cultivation on various lignocellulose substrates, the basidiomycetes of class Agaricomycetes colonize their surfaces and form a three-dimensional mycelium net. Fungal mycelium secretes enzymes that break down lignocellulose over time and are partially replaced by mycelium. The mycelium adheres to the residual undegraded substrates resulting in the formation of a high-mechanical-strength bio-material called a mycelium based bio-composite. The mycelium based bio-composites are completely natural, biodegradable and can be composted after their cycle of use is completed. The physicochemical, mechanical, and thermodynamic characteristics of mycelium based bio-composites are competitive with those of synthetic polymers and allow them to be successfully used in the construction, architecture, and other industries.