Optimization of enzymatic saccharification of industrial wastes using a thermostable and halotolerant endoglucanase through Box-Behnken experimental design

• Published in: Preparative biochemistry & biotechnology 2024, Vol.54 (1), p.1-11
• Main Authors: Santos Gomes, Marta Maria Oliveira dos, Nicodemos, Izadora Santos, Costa Silva, Monizy da, Santos, Dávida Maria Ribeiro Cardoso dos, Santos Costa, Floriatan, Franco, Marcelo, Pereira, Hugo Juarez Vieira
• Format: Article
• Language: English
• Subjects: Agricultural wastes; Agro-industrial waste; Bagasse; Biofuels; Biomass; Calcium - chemistry; Calcium ions; Cellulase - chemistry; Cellulose; Cocoa; Copper; Copper - chemistry; Design of experiments; Design optimization; Dietary Fiber; Endoglucanase; Enzymatic activity; Enzymes; Experimental design; Fermentation; Fungi; Industrial Waste; Industrial wastes; Lignocellulose; lignocellulosic materials; Magnesium; Magnesium - chemistry; Metal ions; Optimization; Organic solvents; Research Design; response surface methodology; Saccharification; Saccharum - metabolism; Salinity tolerance; Sodium chloride; Solid state fermentation; Substrates; Sugar; Sugarcane; Sugars; Wheat; Wheat bran; Zinc; Zinc - chemistry
• ISSN: 1082-6068; 1532-2297
• DOI: 10.1080/10826068.2023.2201936

This study describes the production, characterization and application of an endoglucanase from Penicillium roqueforti using lignocellulosic agro-industrial wastes as the substrate during solid-state fermentation. The endoglucanase was generated after culturing with different agro-industrial wastes for 96 h without any pretreatment. The highest activity was obtained at 50 °C and pH 4.0. Additionally, the enzyme showed stability in the temperature and pH ranges of 40-80 °C and 4.0-5.0, respectively. The addition of Ca 2+ , Zn 2+ , Mg 2+ , and Cu 2+ increased enzymatic activity. Halotolerance as a characteristic of the enzyme was confirmed when its activity increased by 35% on addition of 2 M NaCl. The endoglucanase saccharified sugarcane bagasse, coconut shell, wheat bran, cocoa fruit shell, and cocoa seed husk. The Box-Behnken design was employed to optimize fermentable sugar production by evaluating the following parameters: time, substrate, and enzyme concentration. Under ideal conditions, 253.19 mg/g of fermentable sugars were obtained following the saccharification of wheat bran, which is 41.5 times higher than that obtained without optimizing. This study presents a thermostable, halotolerant endoglucanase that is resistant to metal ions and organic solvents with the potential to be applied in producing fermentable sugars for manufacturing biofuels from agro-industrial wastes.