Obtaining chitin through the optimization of submerged fermentation conditions of the fungus Aspergillus niger

Chitin, a biopolymer precursor to chitosan, can be obtained from fungi. To make production viable and scalable, it is essential to use alternative culture media and optimize cultivation parameters. This study aimed to optimize the biomass production of Aspergillus niger via submerged fermentation to obtain chitin. The composition of the culture media and the bioprocess time were evaluated through a Factorial Design 2 ⁴ . The ideal carbon and nitrogen source concentrations were optimized using a Mixture Design, with fungal biomass and chitin yield as the response variables. An experiment was carried out in a bioreactor with a working volume of 5 L for scale up, using the optimized culture conditions for the microorganism. As a result, the culture medium containing 7.5% wheat bran and 2.5% yeast extract was selected for cultivating Aspergillus niger , the predicted values for this condition were 4.40 g L ^-1 of fungal biomass and 25.24% of chitin yield. Through scaling up to a bioreactor, it was possible to obtain 10.20 g L ^-1 and 4.95 g L ^-1 ± 0.06 of biomass and chitin, respectively, after 84 hours of bioprocess. The study demonstrates the possibility of using alternative culture media for the submerged fermentation of Aspergillus niger and chitin production, with the possibility of increasing yields in the scale up of this bioprocess.