Kinetic Studies of Aspergillus ficuum Tannase Enzyme and its Application in Detannification of Grape Juice

Abstract

This investigation was carried out to study the characterization and kinetics of the partially purified Aspergillus ficuum tannase enzyme for commercial scale application in the clarification and detannification of juices like grape. pH, temperature and optimum substrate concentration were determined for the tannase enzyme activity from Aspergillus ficuum. Also, the Crude and partial purified enzyme were tested for detannification grape juice quality characteristics. Results evidenced that it was found that the optimum partial purified tannase parameters were: temperature 50 oC, PH 5.5 and substrate concentration 1.6% as a tannic acidwith 6.155 specific activities of partial purified tannase enzyme with 225.46% relative activity higher than its control. The tannase enzyme showed a higher temperature and lower pH optima than the soluble enzyme and showed 81.61% and 66.36 % tannin removal from grape juice by crude enzyme and partial purified enzyme treatment, respectively at 37 oC, which has not been reported earlier. Also, maximum velocity of reaction (Vmax) and Michaeli’s constant (Km) values were 0.72 and 1.45 for partially purified tannase enzyme activity, respectively. Overall the quality of grape juice was better in partial pure tannase treated juice compared with untreated and crude enzyme treated juice. The present study exposed thatthis enzyme could demonstrate a valuable tool for a number of biotechnological applications. Also, the application of this enzyme on juice clarification also states that it can be employed in fruit juice processing for removal of tannin efficiently.