Jacob D Zahler, Bishnu Karki, Isabel Isaac and William R Gibbons
The aim of this study was to convert a soybean processing industry wastewater stream into a protein-rich animal feed via fungal bioprocessing while simultaneously reducing the potential environmental impact of the waste stream. Eight fungal strains were screened in flask trails for their ability to produce protein-rich biomass while simultaneously reducing solids found in the wastewater stream. Trichoderma reesei, Paecilomyces variotii and Neurospora crassa produced 51.7, 47.1 and 43.2 g/L of biomass in flask trials while reducing solids present in the supernatant fraction by 46.5, 48.9 and 49.1%, respectively. In bioflo fermenters, Trichoderma reesei and Neurospora crassa produced 55.5 and 62 g/L of protein-rich biomass while reducing chemical oxygen demand (COD) levels by 10.53 and 23.04%, respectively. Microbial metabolic process led to the production of protein-rich animal feed and simultaneously reduced the level of organic matter in the wastewater stream.