Optimisation of solid-state fermentation parameters for the xylanase produced by Aspergillus niger using agro-waste as the substrate

Agro-waste has been an issue in society. It can cause harm to the environment such as soil infertility and becoming an invasive species. Other than that, improper disposal of agro-waste by burning can as well cause air pollution. However, this can be prevented by exploiting the waste as the solid-state fermentation substrate for the manufacture of useful products for instance enzymes. The substrate used was oil palm fronds. The optimization of solid-state fermentation parameters was incubation period, incubation temperature, and initial moisture content. The desired Aspergillus sp. used was Aspergillus niger. This research used a xylanase assay to determine the total xylanase activity. Then, the amount of xylose released was determined by using the dinitro-salicylic acid method. The highest xylanase activity was recorded as 7.681 ± 3.255 U/ml. In conclusion, the optimized parameters to produce the highest xylanase activity are 6 days of the incubation period, 30 °C of incubation temperature and 70 % w/v of initial moisture content