Novel eco-friendly biocatalyst: soybean peroxidase immobilized onto activated carbon obtained from agricultural waste

Abstract

The immobilization of enzymes is an excellent alternative to overcome the drawbacks of using these biocatalysts in free form. This process plays a significant role in cost-effective recovery, increased catalyst productivity and in simplifying process operations. After the soybean peroxidase (SP) extraction, a residue at high carbon and low ash content is generated. This residue was used as carbonaceous precursor for production of carbon activated (AC) with high surface area (1603 m² g⁻¹). The AC produced was used as support for SP immobilization. The immobilization of SP was evaluated in different time conditions, enzyme load, pH and temperature. The samples, before and after immobilization, were characterized by thermogravimetric analysis, elemental analysis composition, specific surface area, X-ray powder diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy. In addition, repeated applications of immobilized biocatalyst were made in order to evaluate its operational stability and capacity to recover the reaction medium, in which was observed that after a decline in activity from the first to the second cycle, it remained constant until the tenth application. In the context, the process of material obtainment constitutes a clean route for the development of more sustainable biocatalysts capable of applications in various areas.