Production of tannase through solid state fermentation using Indian Rosewood (Dalbergia Sissoo)sawdust—a timber industry waste

Abstract

The tannase producing strain Aspergillus heteromorphus MTCC 8818 was used in the present study for the production of tannase under solid state fermentation using Rosewood (Dalbergia sissoo) sawdust—a timber industry waste—as substrate. Various physico-chemical parameters were optimized for extracellular yield of tannase. Maximum tannase (1.84 U/g dry substrate) and gallic acid (5.4 mg/g ds) was observed at 30 °C after 96 h of incubation. Czapek dox medium was found to be the best moistening agent, with pH and relative humidity of 5.5 and 70 %, respectively. The constituents of Czapek dox medium were varied to enhance enzyme production. The optimum concentration of modified Czapek dox constituents contained 0.2 % NaNO3, 0.05 % K2HPO4 and MgSO4, 0.15 % KCl. Among the additional salts supplemented to Czapek dox medium, ZnSO4 and CuSO4 were found to have a stimulating effect, with a relative tannase activity of 116 and 111 %, respectively. Glucose as an external carbon source was found to be a repressor of enzyme production.