UTILIZATION OF WHEAT BRAN FOR ENHANCED PRODUCTION OF EXO-POLYGALACTURONASE BY Penicillium notatum USING RESPONSE SURFACE METHODOLOGY

Response surface methodology (RSM) has been one of the most commonly used optimization method in the recent years. Especially this technique is frequently used in the enzyme biotechnology. In this context Penicillium notatum was evaluated for enhanced biosynthesis of exo-polygalacturonse using statistical approach under solid state fermentation (SSF). Nine parameters were assessed for maximum biosynthesis of the enzyme using classical method (data not shown). Four factors (3 numerical and 1 categorical factor) were evaluated as the best having the influential effect on enzyme yield. These factors were incubation time (days), temperature (°C), pH, and nitrogen sources. Nitrogen sources like glycine and ammonium chloride, were selected in RSM optimization as they were found to be the most promising in multiplying the exo-polygalacturonse activity during the classical approach. Maximum activity of the enzyme achieved was 1129.62 U/gds with incubation period 3 days, pH 1.318, temperature 30 °C and using ammonium chloride as nitrogen source. All the experiments were performed at 40 % (V/W) moisture level using 10 g of wheat bran as substrate. An increase of 5.5 folds of activity was observed using this technique as compared to classical method. The results indicated that RSM could be used to get enhanced activities of exo-polygalacturonse under SSF.