Optimization of culture conditions for production of phytase by Aspergillus niger

Abstract

In this research, the environmental and nutritional factors that control the improvement of phytase enzyme production from the two highest phytase producing fungi Aspergillus niger isolate no 62 and Aspergillus terreus isolate no 24 out of 99 isolated fungi from local soil samples were studied. It was found to have the highest enzyme activity after 8 days of incubation period, temperature of 30 ° C, initial pH of 6 in case of Aspergillus niger isolate no 62 and 12 days, temperature of 25 ° C and initial pH of 6.5 in case of Aspergillus terreus isolate no 24, where It was found that these are the best environmental conditions for maximum enzyme production. The Aspergillus niger isolate no 62 was chosen as the best phytase producing fungi. By studying the effect of different nutritional factors, it was found that sucrose was the best source of carbon, giving the highest enzyme activity at an optimal concentration of 1.5% (weight / volume), and ammonium nitrate when used at a concentration of 0.6% (weight / volume) was found to be the best source of nitrogen to produce phytase enzyme. When studying the effect of different concentrations of the substrate on enzyme production, it was found that when used at a concentration of 3 g / L, the substrate showed maximum phytase production. The descending sequence of agricultural waste according to phytase production by A. niger is as follows: wheat bran> rice bran> cotton stems> broad beans> cotton stems> pomegranate pulp> pea husks.