Solid-State Fermentation of Acid-Resistant <i>Aspergillus niger</i> A515: An Approach to Degrade AFB₁ and ZEN and Enhance Nutritional Components in Maize Products

Aflatoxin B1 (AFB1) and zearalenone (ZEN) pose serious threats to food and feed safety. This study explores the potential of Aspergillus niger A515 to degrade AFB1 and ZEN and improve the nutritional quality of maize-based products. A. niger A515 showed a strong degradation ability, achieving rates of 71.28% for AFB1 and 86.37% for ZEN (initial concentration: 2 μg/mL). In addition, the strain maintained high degradation activity under acidic conditions. Under solid-state fermentation (SSF), optimized via a single-factor approach, A515 effectively degraded mycotoxins in various maize substrates. The highest detoxification rates were observed in maize husk and germ meal (64.58% for AFB1, 93.67% for ZEN), followed by maize protein and whole maize. SSF also significantly increased the protein and amino acid content in the substrate while reducing phytic acid and fibers. These results support the application of A. niger A515 as a safe and effective agent for mycotoxin-contaminated maize-based products.