Optimization of culture conditions for tannase production by Aspergillus sp. gm4 in solid state fermentation

The production of tannase by Aspergillus sp. GM4 under solid-state fermentation (SSF)  was investigated using different vegetables leaves such as mango, jamun, coffee and agricultural residues such as coffee husks, rice husks and wheat bran. Among substrates used jamun leaves yielded high tannase production. The Plackett-Burman design was conducted to evaluate the effects of 12 independent variables on the production of tannase under SSF using jamun leaves as substrate. Among these variables, incubation time, potassium nitrate and tannic acid had significant effects on enzyme production. The best incubation time was studied and others variables were optimized using the Central Composite Design. The best conditions for tannase production were: incubation time of 2 days; tannic acid 1.53% (w/w) and potassium nitrate 2.71% (w/w). After the optimization process, the tannase production increased 4.65-fold. Keywords : surface response methodology; enzyme; jamun