Influence of Agro-Waste Substrates on the Growth, Nutritional Composition, Phytochemical Profile, Antimicrobial, and Antioxidant Properties of Pleurotus pulmonarius and Pleurotus florida

Agro-based wastes provide sustainable and nutrient-rich alternatives to synthetic substrates for mushroom cultivation. This study examined the effects of different substrates on the nutritional composition, phytochemical profile, antimicrobial, and antioxidant properties of Pleurotus pulmonarius and Pleurotus florida . Corn cob, sawdust, and compost waste were used to assess their influence on growth performance and bioactive compound production. Standard analytical methods were employed to determine proximate composition, total phenolics, flavonoids, and antioxidant capacity, while antimicrobial activities were evaluated against selected bacterial and fungal pathogens using aqueous extracts. High-performance liquid chromatography (HPLC) was used to quantify aflatoxin residues. Results revealed that sawdust supported the highest mycelial growth and yield, followed by corn cob, while compost waste produced lower performance. P. florida exhibited superior antioxidant and antibacterial activities compared to P. pulmonarius , with the highest inhibition recorded against Staphylococcus aureus and Escherichia coli . Both species also showed strong antifungal effects against Aspergillus species. Trace concentrations of aflatoxin B₁, B₂, and G₁ detected in the samples suggest possible substrate-related contamination rather than endogenous production. These findings demonstrate that substrate composition significantly affects the nutritional and bioactive properties of Pleurotus species. The use of lignocellulosic agro-wastes such as sawdust and corn cob not only enhances mushroom productivity and bioactivity but also promotes sustainable waste management and functional food development.