statistical optimization of tannase production by penicillium sp. ez-zh390 in submerged fermentation

tannase has several important applications in food, feed, chemical and pharmaceutical industries. in the present study, production of tannase by mutant strain, penicillium sp. ez-zh390, was optimized in submerged fermentation utilizing two statistical approaches. at first step, a one factor at a time design was employed to screen the preferable nutriments (carbon and nitrogen sources of the medium) to produce tannase. screening of the carbon source resulted in the production of 10.74 uml-1 of tannase in 72 h in the presence of 14% raspberry leaves powder. a 1.99-fold increase in tannase production was achieved upon further screening of the nitrogen source (in the presence of 1.2% ammonium nitrate). then the culture condition variables were studied by the response surface methodology using a central composite design. the results showed that temperature of 30°c rotation rate of 85 rpm and fermentation time 24 h led to increased tannase production. at these conditions, tannase activity reached to 21.77 uml-1, and tannase productivity was at least 3.55 times (0.26 uml-1h-1) in compare to those reported in the literature. the present study showed that, at the optimum conditions, penicillium sp. ez-zh390 is an excellent strain for use in the efficient production of tannase.