Kinetic, logistic, box-behnken model and statistical procedure for media optimization of tannase producing bacteria from tannery effluent and its application in Glue and gelatine production for pharma applications

Abstract

A key enzyme tannase enables the degradation of gallotannins, a type of hydrolysable tannins. A wide variety of microorganisms such as yeasts, fungi and bacteria leads to the production of tannase. Among these the tannase producing bacteria were commonly reported in dissipated water from paper, leather and forestry industries. In this study we will discuss about diverse bacteria that were isolated from the tannery effluent of several industries and its screening, characterization and the production of extracellular tannase. The production of extracellular tannase is highly influenced by Media Optimization and hence wide range of pH and temperature is utilized for the production of tannase and the optimal activity was found to be at 45°C and at a pH 6.5. The placket-Burman Logistic, Kinectic and Box-Behnken models were employed to optimize the media for tannase producing bacteria. In submerged culture (SMC) and solid-state (SSC) the induction and repression pattern of tannase production can be observed and the results presented that SSC has higher potential to minimize catabolite repression. Assessment of the effect of various additives on tannase activity was also done and thus among the various metal salts tested, the enzyme was found to be strongly inhibited byHgCl2 followed by ZnCl2 and MnCl2. Again it was also found that EDTA and ?- mercaptoethanol had inhibitory effect where as the detergents (Tween-20, -60 and -80 as well as SDS) did not affect the activity of the enzyme1. The recovery of glue and gelatin from tannery effluent was also studied and for that a three step hydrolysis process is best suited for maximum recovery of collagen hydrolysate followed by the glue and gelatine production from it. It was also reported in accordance with the antibiotic sensitivity test (Abst) that the bacteria were very sensitive for streptomycin.