Roheena Abdullah, Mariam Saeed, Hira Butt, Afshan Kaleem, Mahwish Aftab, Mehwish Iqtedar
The growing accumulation of agro-industrial residues poses environmental challenges but also offers opportunities for sustainable biotechnological valorization. This study presents an integrated microbial bioprocess to transform agro waste into valuable industrial enzymes using a fungal consortium under solid-state fermentation (SSF). Two compatible fungal strains, Aspergillus flavus and Aspergillus niger, were selected for their high enzymatic potential and identified through morphological and molecular approaches. The consortium achieved maximal co-production of α-amylase and cellulase after 48 h, with alkaline-treated substrates. Scanning Electron Microscopy (SEM) revealed notable structural alterations in the substrates after alkali treatment. Among all substrates tested, alkali-pretreated potato peel showed the greatest potential for α-amylase and cellulase co-production. To further enhance process efficiency, statistical bioprocess modeling using Response Surface Methodology (RSM) was employed. Plackett-Burman Design (PBD) screening highlighted pH, inoculum size, and inoculum age as critical factors, which were optimized via Central Composite Design (CCD). The optimized conditions-pH 5.5, inoculum age 4 days, and inoculum size of 3 mL resulted in markedly improved α-amylase and cellulase co-production. Nutritional optimization demonstrated that balanced supplementation with maltose, ammonium nitrate, peptone, and Tween 80 further enhanced synthesis. The statistical models exhibited strong predictive capability with high coefficients of determination, confirming bioprocess reliability. Overall, this study introduces a novel strategy integrating fungal consortium-mediated co-production of α-amylase and cellulase with advanced statistical modeling for efficient agro-waste valorization. The developed platform provides an eco-friendly approach to convert agricultural residues into industrially valuable enzymes, promoting sustainable waste management and advancing circular bioeconomy initiatives.