Innovative chitin-glucan based material obtained from mycelium of wood decay fungal strains

Abstract

Fungi are an alternative source to animal-based chitin. In fungi, chitin fibrils are strongly interconnected and bound with glucans that justify the unique matrix. The present study aimed to extract chitin and glucans from the mycelium of several wood decay fungal strains in order to obtain flexible materials and to check correlations between chitin content and the mechanical properties of these materials. Five strains were chosen in consideration of their different cell wall chemical composition (high content of α-glucans, β-glucans or chitin) to evaluate how these differences could influence the mechanical and chemical characteristics of the material. The fungal strains were cultivated in liquid-submerged dynamic fermentation (both flasks and bioreactor). Chitin and glucans were crosslinked with acetic acid and plasticized with glycerol to obtain flexible sheets. Abortiporus biennis, Fomitopsis iberica and Stereum hirsutum strains were found to adapt to produce material with adequate flexibility. The obtained materials were characterized by Thermogravimetric analysis (TGA) for the understanding of the material composition. The material obtained from each species was mechanically tested in terms of tear strength, elongation at break, and Young's modulus.

Keywords

• Myco-materials
• Wood decay fungi
• Flexible materials
• Chitin-glucan-materials
• Nanofiber papers