A biochemical characterization of the tannase from a Paecilomyces variotii strain isolated in Sao Paulo, Brazil was carried out. Paecilomyces variotii is a strain obtained from the screening of five hundred fungi that were tested for their production of tannase. The enzyme produced was partially purified using ammonium sulfate precipitation followed by ion exchange chromatography, diethylaminoethyl ( DEAE)-Sepharose. Effects of temperature and pH on the activity of crude tannase crude and purified tannase was studied. Km was found to be 0.61 mu mol and V-max = 0.55 U/mL. Temperature of 40 to 65 degrees C and pH 4.5 to 6.5 were optimum for tannase activity and stability; it could find potential use in the food-processing industry. The effects of different inhibitors, surfactants and chelators on the enzyme activity were also studied.102191199