Biochemical properties and catalytic performance of a Trichoderma koningiopsis serine protease produced from Hermetia...

The industrial demand for proteases necessitates the development of cost-effective and sustainable production processes. Leveraging insect biomass, such as Hermetia illucens meal, aligns with circular bioeconomy principles and offers a promising alternative to fungal fermentation substrates. This study reports, for the first time, protease production by filamentous fungi isolated from the Caatinga-Cerrado ecotone using Hermetia illucens meal as a substrate for solid-state fermentation (SSF). T. koningiopsis UFPIT03 showed the highest activity (88.24 U/mL). A 2³ factorial design identified moisture (30%) as a key factor for this activity. Purification via salting-out and ion-exchange chromatography achieved a 15-fold increase in purity (46.13 kDa). The enzyme exhibited optimal activity at pH 7.0 and 50 °C and was characterized as a trypsin-like serine protease. Kinetic analysis revealed a high substrate affinity, whereas thermodynamic parameters demonstrated high conformational stability and a non-spontaneous denaturation process. Furthermore, the protease exhibited remarkable compatibility with various commercial detergents, retaining substantial residual activity. These results highlight the potential of T. koningiopsis to produce robust neutral proteases using insect biomass. The stability and resilience of the enzyme in detergent formulations validate its suitability for biotechnological applications, offering a viable path for the valorization of alternative resources within the global bioeconomy.