Production, characterization and purification of tannase from Aspergillus niger

Tannin acyl hydrolase (E.C.3.1.1.20) commonly referred to as tannase, is an industrially important enzyme that is mainly used in the food, chemical, beverage and pharmaceutical industry. In this study, tannase production was investigated using Aspergillus niger isolated from bark of tannin rich Acacia nilotica. Optimization of culture conditions for maximum tannase production included studying the effects of incubation period, incubation temperature, pH, carbon and nitrogen sources, inducers and metal ions on A. niger and enzyme activity. The optimum culture conditions determined were tannic acid as inducer, 7 days(168hrs) incubation period, 30°C incubation temperature, pH 5.0, 1%(w/v) tannic acid as carbon source and 1%(w/v) sodium nitrate as nitrogen source for maximum tannase activity. Tannase was purified 7.17 fold with a specific activity of 101.428U/ml protein and a yield of 18.35%. Molecular characterization included the zymography and purification of tannase enzyme.