Thermophilic Fungal-based Composting Accelerator to Enhance Phosphorus Cycling in Urban Organic Waste

Organic waste valorisation through solid-state fermentation (SSF) represents a promising strategy for sustainable nutrient recovery and composting enhancement. This study evaluated the production of hydrolytic enzymes by the thermophilic fungus Myceliophthora thermophila I-1D3b cultivated on different agro-industrial and urban residues aiming to evaluate hydrolytic enzyme production with potential application in composting-related processes. Six substrate formulations were investigated: sugarcane bagasse and wheat bran, sugarcane bagasse and soybean meal, tree pruning residues and wheat bran, fruit residues, fruit residues supplemented with sawdust, and rice. Fermentations were conducted at 45 °C for 120 h under controlled moisture conditions (60–75%), with standardized inoculation using spore suspension. Enzymatic activities, including phosphatase, amylase, endoglucanase, protease, lipase and chitinase, were determined by spectrophotometric methods. Substrate composition strongly influenced enzymatic production. Tree pruning residues and wheat bran showed the highest overall performance, reaching phosphatase activity of 52.71 µmol·min.¹·L.¹, in addition to elevated amylase and endoglucanase activities. This study establishes thermophilic fungal SSF as a promising approach for the development of enzyme-based composting accelerators, contributing to potential improvement in organic matter degradation and nutrient recovery and sustainable management of organic waste within circular bioeconomy frameworks.