Production of nigerloxin, an enzyme inhibitor and a free radical scavenger, by Aspergillus niger using solid state fermentation

The fermentation parameters of production of nigerloxin, an inhibitor of lipoxygenase, through solid state fermentation by Aspergillus niger CFR-W-105 and its recovery was studied. Inhibitor production was influenced by the nature of the solid substrate, moisture content, incubation temperature, carbon, nitrogen, lipid and mineral supplements. Nigerloxin production was the highest when wheat bran was supplemented with 5% (w/w) trisodium citrate. The maximum nigerloxin obtained was 5.06 mg/g of dry wheat bran. Extraction of the fermented wheat bran using ethyl acetate under acidic pH range of 4–5.5 under agitated conditions resulted in maximum inhibitor recovery. Optimum time and temperature of extraction were determined to be 90 min and 30 °C, respectively.