OPTIMIZATION OF TANNASE PRODUCTION BY ASPERGILLUS FLAVUS

Tannase (Tannin acyl hydrolase, EC: 3.1.1.20) is one of the hydrolytic microbial enzyme and it is considered as important industrial enzyme, which has many industrial applications. The enzyme was isolated from Aspergillus flavus and its productivity was optimized. The effect of various concentrations of tannic acid on tannase production was examined and it was found that 2% (w/v) was the best concentration. The optimum pH for tannase production was 5.5. The highest tannase production was noticed after incubation period of 96h and optimal temperature of 30οC. Various carbon sources including starch, dextrin, sucrose, maltose, glucose, fructose, arabinose and xylose were tested regarding their effects on tannase production. Tannin, gallic acid and tannic acid were also tested. Tannic acid was the best carbon source for enzyme induction .Tannic acid and gallic acid were the most effective inducers for tannase followed by tannin. The Effect of different nitrogen sources on tannase production was carried out using organic and inorganic nitrogen sources including yeast extract, casein, peptone, ammonium sulphate, Potassium nitrate, sodium nitrate and ammonium nitrate. Sodium nitrate was the best inducer for tannase production followed by ammonium nitrate. Studying the effect of various concentrations of sodium nitrate revealed that 0.6% sodium nitrate was the most effective concentration for tannase production.