Received: 14 July, 2012. Accepted: 14 August, 2012. Invited Review Dynamic Biochemistry, Process Biotechnology and Molecular Biology ©2012 Global Science Books Fungal Tannase: A Journey from Strain Isolation to Enzyme Applications Debdulal Banerjee * • Subhadip Mahapatra Microbiology Laboratory, Department of Botany and Forestry, Vidyasagar University, Midnapore- 721102, West Bengal, India Corresponding author: * debu33@yahoo.com, db@mail.vidyasagar.ac.in ABSTRACT Tannase is an important enzyme and plays an important role in plant polyphenol degradation as well as conversion to very important pharmaceutical products. Even though this enzyme is widely applied to different food and beverage industries, its industrial production, proper induction and catalysis mechanism still remain limited. This review presents an illustrated revision on fungal tannase. Emphasis had been laid on fungal strains which can produce tannase, different fermentation processes of tannase production, tannase purification, structural and functional characteristics of this enzyme, different enzyme assay techniques and applications of this enzyme. A probable mechanism of tannin degradation by fungus is briefly described. _____________________________________________________________________________________________________________ Keywords: Application, fungal tannase, production, properties, tannase assay CONTENTS INTRODUCTION........................................................................................................................................................................................ 49 SUBSTRATE FOR TANNASE PRODUCTION ......................................................................................................................................... 49 MECHANISM OF TANNIN METABOLISM............................................................................................................................................. 50 FUNGAL TANNASE PRODUCERS .......................................................................................................................................................... 50 PRODUCTION OF TANNASE ................................................................................................................................................................... 50 MODE OF FERMENTATION..................................................................................................................................................................... 50 Submerged fermentation.......................................................................................................................................................................... 52 Solid state fermentation ........................................................................................................................................................................... 53 PURIFICATION OF TANNASE ................................................................................................................................................................. 54 TANNASE ASSAY METHODS .................................................................................................................................................................. 54 PROPERTIES OF TANNASE ..................................................................................................................................................................... 56 APPLICATIONS OF TANNASE................................................................................................................................................................. 57 CONCLUDING REMARKS ....................................................................................................................................................................... 57 ACKNOWLEDGEMENTS ......................................................................................................................................................................... 58 REFERENCES............................................................................................................................................................................................. 58 _____________________________________________________________________________________________________________ INTRODUCTION Tannins are plant polyphenolic compounds having high antimicrobial activity and easily precipitate any protein due to their complexation with proteins and enzymes. However, few organisms are known to have the ability to survive in a tannin-rich environment by production of tannase (Ver- meire and Vandamme 1988). Tannin acyl hydrolase (E. C. 3.1.1.20) or tannase was accidentally discovered in 1867 by Van Tieghem (Aguilar et al. 2007). This adaptive, inducible hydrolase catalyzes the hydrolysis of depside and ester bonds in varied substrates like, gallo tannins; gallic acid esters; epicatechin gallate; epigallocatechin-3-gallate, rel- easing glucose and galic acid (Bajpai and Patil 1996; Bradoo et al. 1997; Lekha and Lonsane 1997; Banerjee et al. 2001; Banerjee and Pati 2007; Kasieczka-Burnecka et al. 2007; Robledo et al. 2008; Mahapatra and Banerjee 2009; Lokeswari et al. 2010; Renovato et al. 2011; Costa et al. 2012). Tannase expand its commercial importance for not only its pharmaceutical important end product gallic acid, but also, there are several applications of treated substrate of tannase. From the last few decades tannase is widely applied in the production of instant tea, clarification of beer and fruit juices, manufacture of coffee flavored soft drinks, improvement in the flavor of grape wine and as an analy- tical probe for determining the structures of naturally occur- ring gallic acid esters (Bajpai and Patil 1996; Lekha and Lonsane 1997). Although, tannase can obtained from plant, animal and microbes but the most common and important source to obtain this enzyme is from microbes due to better production, low costing and high stability of microbial tannase (Lekha and Lonsane 1997). Among the microorga- nisms fungi are the most predominant source of tannse producer. At present most of the commercialized tannase is produced by fungi like tannase of Biocon (India), Kikko- man (Japan) ASA Special enzyme GmbH (Germany) and JFC GmbH (Germany). There are few reviews published on microbial tannase. In this communication attention has been paid to fungal tan- nase; from production to application. SUBSTRATE FOR TANNASE PRODUCTION Tannins are naturally occurring water soluble polyphenolic plant secondary metabolites with varying molecular weights ranging from 300 D to 3000 D (Haslam 1989). It is the ®