eng Oriental Scientific Publishing Company Biosciences Biotechnology Research Asia 0973-1245 2020-08-10 3 2a 36750 article N. Lokeswari 1 M. Narasimha Rao 1 K. Jaya Raju 1 C. Ayyanna 1 Center for Biotechnology, Department of Chemical Engineering, Andhra University, Visakhapatnam - 530 00, India A comparative study on the production of Gallic acid using three different types of tannin rich substrates viz Anacardium occidentale, Caesalpinia digyna, Caesalpinia coriaria was conducted in the present work. Among these three substrates Caesalpinia digyna is richest source of Tannins as it contains 50% Gallotannins of total tannins, which is more than that of other two substrates (A. occidentale 26%, C. coriaria 43%). Some important parameters like substrate concentration, pH, temperature, inoculum level, fermentation time were optimized for the hydrolysis of Gallotannin from the above said three substrates by using Fusarium solani MTCC 350 which produces tannase enzyme when induced with 5g^L-1 gallotannin. The highest yield of Gallic acid could be obtained from Caesalpinia digyna pod cover powder at substrate concentration 4 % (w/v), pH 5, temperature 35^OC, inoculum level 8 ml, and fermentation time of 3 hours. Hence this method produces more yield of Gallic acid from Teri tannins and at the same time it is free from pollution. https://www.biotech-asia.org/vol3no2a/comparative-study-on-biotransformation-of-tannin-rich-agro-forest-based-products-into-gallic-acid-by-fusarium-solani-mtcc-350/ Anacardium occidentale; Caesalpinia digyna; Caesalpinia coriaria; Fusarium solani; Gallic Acid; Tannin Tannase