Evaluation of Culture and Plasticisation Conditions for the Production of Pure Mycelium Materials from Aspergillus Niger

Abstract

Biodegradable mycelium-based materials were produced by growing Aspergillus niger under three submerged culture conditions—static, agitated, and combined (agitated-static)—in Sabouraud Glucose Broth for 7 days at 37 °C. Mycelia production and morphology were evaluated. The mycelia obtained from agitated and combined cultures were selected for plasticisation assay by immersion in 0, 25, and 50 wt.% glycerol for 3, 12, and 24 h. The resulting pure mycelium materials were pressed under a uniform weight at 6.4 g/cm2 (≈ 0.627 kPa) for 72 h. After 100 days of storage at room temperature and ambient humidity, all glycerol-plasticised materials remained visually free of contamination and maintained good handleability with no differences among the immersion times. Subsequently, mycelia obtained from the combined culture and plasticised for 3 h were tested for mechanical properties (Young’s modulus, tensile strength, and elongation at break) and home-compost disintegration. In general, non-plasticised (control) materials exhibited higher Young’s modulus and tensile strength, whereas glycerol-treated samples showed a notable reduction in rigidity accompanied by a significant enhancement in elongation at break. Compost disintegration assays showed over 50 % disintegration within 30 days, reaching a 59.7 % disintegration after 95 days. Although further studies are required to characterise the resulting materials and evaluate their potential applications, this study demonstrates the potential of fungal cultivation to develop sustainable and compostable materials as viable alternatives to conventional plastic packaging.