Sugarcane Bagasse Saccharification by Enzymatic Hydrolysis Using Endocellulase and β-glucosidase Immobilized on Different Supports

Abstract

The saccharification of sugarcane bagasse by enzymatic hydrolysis is one of the most promising processes for obtaining fermentable sugar to be used in the production of second-generation ethanol. The objective of this work was to study the immobilization and stabilization of two commercial enzymes: Endocellulase (E-CELBA) in dextran coated iron oxide magnetic nanoparticles activated with aldehyde groups (DIOMNP) and β-glucosidase (E-BGOSPC) in glyoxyl agarose (GLA) so that their immobilized derivatives could be applied in the saccharification of pretreated sugarcane bagasse. This was the first time that the pretreated sugarcane bagasse was saccharified by cascade reaction using a endocellulase immobilized on dextran coated Fe2O3 with aldehyde groups combined with a β-glucosidase immobilized on glyoxyl agarose. Both enzymes were successfully immobilized (more than 60% after reduction with sodium borohydride) and presented higher thermal stability than free enzymes at 60, 70, and 80 °C. The enzymatic hydrolysis of the sugarcane bagasse was carried out with 15 U of each enzyme per gram of bagasse in a solid-liquid ratio of 1:20 for 48 h at 50 °C. Under these conditions, 39.06 ± 1.18% of the cellulose present in the pretreated bagasse was hydrolyzed, producing 14.11 ± 0.47 g/L of reducing sugars (94.54% glucose). In addition, DIOMNP endo-cellulase derivative maintained 61.40 ± 1.17% of its enzymatic activity after seven reuse cycles, and GLA β-glucosidase derivative maintained up to 58.20 ± 1.55% of its enzymatic activity after nine reuse cycles.

Enzyme immobilization: what have we learned in the past five years?

“…sugarcane bagasse). 16,[20][21][22][23][24][25] Various materials (organic or inorganic, nano or microporous) have been applied as supports for enzyme immobilization by different techniques. 19,26,27 These topics will be discussed in the following sections.…”

Utilization of Clay Materials as Support for Aspergillus japonicus Lipase: An Eco-Friendly Approach

“…According to the authors, the incorporation of clay provided a support with greater adsorption capacity and greater rigidity (mechanical resistance), improving its performance. In the studies performed by Morais et al [84] in the immobilization of Endocellulase and β-glucosidase in magnetic iron oxide nanoparticles demonstrated that the enzymatic immobilization improved the thermal stability of the biocatalysts, achieving residual activities of 80% in 72 h of incubation at 60 • C.…”

Immobilization-Stabilization of β-Glucosidase for Implementation of Intensified Hydrolysis of Cellobiose in Continuous Flow Reactors

“…Studies mainly involve the immobilization into preexisting materials and the evaluation of the influence of the material supports in the interplay with different immobilization chemistries. Catalytic properties as recovered activity and stability were evaluated [18][19][20][21][22][23][24][25][26]. Active immobilization by adsorption (anion exchange based ionic adsorption) or covalent binding (via aldehyde chemistry) to porous material supports have been shown as a promising strategy to obtain active and stable catalysts of different βglucosidases.…”

“…Active immobilization by adsorption (anion exchange based ionic adsorption) or covalent binding (via aldehyde chemistry) to porous material supports have been shown as a promising strategy to obtain active and stable catalysts of different βglucosidases. In these previous works, the focus of the immobilization design was obtaining high specific activity (similar to the free enzyme) and enhancing the stability under resting conditions, which represents a promising point for implementation [17,18,[24][25][26][27][28][29][30][31][32].…”