The behavior of kinetic parameters in production of pectinase and xylanase by solid-state fermentation

► We analyzed the influence aeration on the pectianse and xylanase production. ► Respirometric quotient (RQ) was established according each carbon source consumed. ► RQ is not constant along the fermentation due to different carbon source employed. ► Kinetics parameters behavior depends of carbon source consumed from solid matrix. ► Productivities pattern for biomass and both enzymes was established. Solid-state fermentation (SSF) is defined as the growth of microbes without a free-flowing aqueous phase. The feasibility of using a citrus peel for producing pectinase and xylanase via the SSF process by Aspergillus niger F3 was evaluated in a 2kg bioreactor. Different aeration conditions were tested to optimize the pectinase and xylanase production. The best air flow intensity was 1VkgM (volumetric air flow per kilogram of medium), which allowed a sufficient amount of O2 for the microorganism growth producing 265U/g and 65U/g pectinases and xylanases, respectively. A mathematical model was applied to determine the different kinetic parameters related to SSF. The specific growth rate and biomass oxygen yield decreased during fermentation, whereas an increase in the maintenance coefficient for the different employed carbon sources was concurrently observed.