a new native source of tannase producer, penicillium sp. ez-zh190: characterization of the enzyme

background: tannase can be obtained from the various sources for example tannin rich plants; however microbial sources are preferred for industrial production. in microbial sources, the aspergillus and penicillium genus and lactic acid bacteria mostly produce tannase. however, it has been identified that this enzyme is produced by many fungi and bacteria, but researches are continuing to find new species. objectives: the aim of this study was to isolate a tannase-producing fungi from moldy tea leaves and to study some properties of its enzyme. materials and methods: the present study was done via two steps. at first, industrially important tannaseproducing fungi were isolated from moldy tea leaves using the simple agar plate method followed by the screening of organisms capable of producing tannase using the enrichment culture technique in modified czapek dox’s agar. finally, tannase obtained from the best isolate was partially purified and characterized. results: tannase produced by penicillium sp. ez-zh190 isolated from moldy tea leaves was partially purified and characterized. maximum enzyme production (4.33 u.ml-1) was recorded after 96 hours of incubation at 30 °c in submerged culture (100 rpm) utilizing 1% (w/v) tannic acid as a sole carbon source. this tannase exhibited optimum activity at 35 °c and at ph of 5.5, and showed nearly 50% of its maximal activity at 50 °c. in the present study, tannase from penicillium sp. ez-zh190 had km and vmax values of 1.24 mm and 17.09 u.ml-1, respectively, and showed more than 50% stability at salt (nacl) concentration of 1 m for 24 hours. conclusions: tannase productivity of penicillium sp. ez-zh190 (0.045 u.ml-1.h-1) is comparable with the maximum tannase productivity in the reported literatures, and the biochemical characteristics showed by penicillium sp. ez-zh190 tannase are considered favorable for tannin biodegradation in the industry. so, we concluded that penicillium sp. ez-zh190 is a good strain for use in the efficient production of tannase.