Production and optimization of enzyme xylanase by Aspergillus flavus using agricultural waste residues

Abstract

This study aims to isolate xylanase-producing fungi, i.e., Aspergillus flavus, isolated from the litter of the Orchha forest, and efforts are made to culture fungi on cheaper agricultural substrates, i.e., wheat bran and corn cobs. After isolation, the xylanolytic activity was tested on the malt extract agar culture medium. Optimization of growth parameters were also carried out with wheat bran and corn cobs. It was found that maximum xylanase was produced on the sixth and eighth days of incubation, with pH of 6.0 and 7.0, and substrates amount for corn cobs and wheat bran of 16 and 18 mg/ml, respectively. Temperature of 30°C, peptone concentration of 0.5 mg/ ml, and yeast extract concentration of 0.75 mg/ml were the same for both substrates. The enzyme produced through optimized conditions was assayed for its maximum activity. It was found that the enzyme showed maximum activity at 15 and 30 minutes of incubation, and at 60° and 55°C temperature for corn cobs and wheat bran, respectively. The pH and substrate (oat spelt xylan) concentrations were optimized at 5.5 and 15 mg/ml, respectively. In. this study, the production of xylanase with the use of cheaper agricultural waste, such as wheat bran and corn cobs, will not only reduce the cost of production but will also help in their eradication from the environment.