Optimization of Piriformospora indica pectinase production from sugar beet pulp by Taguchi method

Pectinases, as a large group of enzymes, catalysis break down of pectin to smaller molecules including galacturonic acid, and they are widely produced by many microorganisms. Nowadays, abundant waste from agriculture and fruit processing industries including sugar beet pulp, apple and citrus pomace as rich source of pectin are employing to induce pectinase production by many microorganisms. The aim of this study was optimization of Piriformospora indica pectinase production by using sugar beet pulp (SBP) by Taguchi method. First, P. indica was cultured on Kaefer medium supplemented with SBP, then biomass and spore production, enzyme activity and total protein content were measured for ten days. According to the results, maximum biomass production and pectinase activity were detected, 6.125 g/l and 3.2 U/ml in the presence of SBP at 6th day, respectively. Furthermore the effect of different concentrations of glucose and ammonium sulphate and their interaction on enzyme activity was investigated. Based on the results by increasing the amount of them alone the activity was increased but in the case of their interaction with sugar beet pulp the activity was decreased. Next, enzyme production was optimized by Taguchi method to 8.35 U/ml which was 2.5 times more than non-optimized condition. In conclusion, because of pectinase production of P. indica by using sugar beet pulp as a suitable and cheap substrate, economically is valuable and moreover cause to decrease environmental pollution.