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A new type of tannase enzyme produced by bacteria for use in the food industry is described here. In this study, we isolated a large number of lactic acid bacteria (LAB) from various foods. Results of screening from isolating LAB strains revealed that H78 strain has potential to produce tannase in large amounts. The strain was identified as Lactobacillus plantarum by its physiological, morphological, and molecular characteristics. H78 strain induced tannase by 0.1% tannic acid in culture medium. Furthermore, it was purified using two chromatography systems. The monomer protein molecular mass was 50–60 kDa. Its optimum pH was 8.0. Its optimum temperature was 30°C. It was stable at pH 5.0–6.0. It was also stable between 4 and 30°C. Its activity was accelerated slightly by magnesium ion but inhibited by copper, manganese, calcium, iron, and mercury ion. Chelating agents did not inhibit its activity. Results suggest that it is not a metallo-enzyme. Among other tannase substrates, the enzyme reacted against methyl gallate the most, but it reacted against tannic acid less than the other substrates. Keywords: Tannase, Lactobacillus plantarum, Methyl gallate
