Estudo de celulases imobilizadas em suportes a base de quitosana/alginato aplicadas na hidrólise de diferentes resíduos agroindustriais

• Autor(a) principal: Fileti, Jorge Luis Santos
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/12503
• topic: Engenharia Química; Celulases; Imobilização; Quitosana; Alginato

The pursuit of high-value energy production technologies has driven innovation and technology worldwide. One promising avenue is the production of ethanol from lignocellulosic materials, known as second-generation ethanol, through hydrolysis and subsequent alcoholic fermentation. Immobilizing cellulose on insoluble supports in the solution offers a viable approach, enabling enzyme reuse, a critical aspect of the process.Ð'dIn this study, CelluClast 1.5L (Novozymes A/S) was immobilized using chitosan and chitosan-alginate gels activated with glutaraldehyde, which proved to be the most widely adopted method. The research evaluated the immobilization yield, recovered activity, thermal stability, temperature, and optimal pH for enzymatic activity. Among the tested biocatalysts, the chitosan/alginate gel activated with glutaraldehyde demonstrated the best performance.Ð'dThe support material remained intact without fragmentation or structural damage during the hydrolysis of the filter paper. The biocatalyst exhibited an activity of 1.83 FPU/g of support, with a recovered activity of 8.26% and an immobilization yield of 87.72%. The optimal temperature for the derivatives was approximately 50°C, compared to 60°C for the free enzyme. The pH shifted from 4.0 (free enzyme) to 5.0 for the derivatives.Ð'dFor chitosan/alginate supports, a higher enzymatic load resulted in greater activity retained on the support, showing a 68% increase compared to chitosan supports. Specifically, under an enzymatic load of 1280mg of protein/g of support, the chitosan/alginate biocatalyst exhibited significantly enhanced performance. Notably, the hydrolysis of lignocellulosic residues proved to be 2.1 times more efficient using enzymes immobilized in chitosan/alginate with this higher protein load compared to the chitosan biocatalyst.Ð'dIn summary, this study provides a technical assessment of the immobilization process and its impact on enzymatic activity and the efficiency of ethanol production from lignocellulosic materials.