Nanoencapsulação de lipase de botryosphaeria ribis ec-01

Abstract

Enzymes are crucial in various natural processes and are viable, environmentally friendly alternatives to conventional catalysts. Their distinctive features include high catalytic efficiency, substrate specificity, minimal by-product production, and low energy consumption. These properties make enzymes highly attractive targets for academic research and industrial applications. In particular, lipases have stood out due to their versatility, being able to catalyze several reactions, such as hydrolysis. However, the high costs associated with the production and use of these enzymes often make their large-scale application unfeasible. One of the main factors contributing to these costs is the price of the raw materials used to produce enzymes. Strategies such as the use of agro-industrial by-products in the production of the enzyme and its immobilization have been explored to reduce these costs. The use of enzymes in their free form is often hampered by their tendency to denaturation and inactivation during the reaction processes. Therefore, alternatives that increase their stability are sought, and a promising solution is their nanoencapsulation. The present study aimed to nanoencapsulate lipases in a sodium zein-caseinate matrix to increase enzymatic stability. The lipases were produced by submerged fermentation using the filamentous fungus Botryosphaeria ribis EC-01, under optimized conditions, using soybean meal, a by-product of the soybean oil industry, and glycerol as substrates. The sodium zein-caseinate nanoparticles were synthesized using the antisolvent precipitation method, being carried out in different volumetric proportions of ethanol: water 80:20/lipase solution: 65/35 (35%), 75/25 (25%), and 85/15 (15%). The colloidal systems were characterized by dynamic light scattering (DLS) technique regarding hydrodynamic diameter, zeta potential and polydispersity index (PDI) during 35 days of storage at 4 °C, encapsulation efficiency (EE), load capacity (CC), Fourier Transform Infrared Spectroscopy (FTIR) and thermogavimetric analysis (TGA/DTG). The lipolytic activity was performed from the hydrolysis of p-nitrophenyl palmitate (pNPP) at 55 °C, pH 8, for 2 minutes, and at 410 nm. Based on the results obtained during the 35 days, the properties of hydrodynamic diameter, PDI, and zeta potential were not influenced by the lipase concentration, demonstrating no significant difference between their values, indicating stability and homogeneity of the colloidal system. The highest EE was found for the nanoparticles prepared with 25% and 35% lipase, and the CC did not show a significant difference for the three lipase proportions. The FTIR and TGA/DTG spectra analyses confirmed the encapsulation of lipase. Based on the results obtained, 25% and 35% lipase concentrations can be used to prepare nanoparticulate colloidal systems of zein coated with sodium caseinate with high efficiency.