Effect of agar concentration on structure and physiology of fungal hyphal systems

Hyphae are the filamentous branches that form a mycelial network, acting as the constitutive structure of mushroom-forming Fungi. Hyphae grow on many substrates and in multitudes of environmental conditions. Due to this versatility, hyphae are of increasing interest in the area of bio-constructed materials derived from sustainable and non-petroleum-based inputs. By understanding the effects of external factors on the growth and physical properties of the hyphae, we can manipulate the physical properties of a cultivated mycelial sheet. This study demonstrates how altering the agar concentration during in vitro culturing can affect the physical growth and structure of the mycelial sheet without altering its permeability or chemical makeup. When the agar concentration was increased from 1.5% agar to 6.0% agar, the mycelium density and hyphal width increased by 32.3% and 63.6%, respectively. The implications of these findings will allow for the advancement and tuning of fungi-based materials, particularly for the application of sustainable textiles and fine particulate filters.