Pretreatment of sugarcane bagasse using deep eutectic solvents to enhance cellulose hydrolysis

Abstract

Sugarcane bagasse is a promising lignocellulosic biomass for glucose production and other value-added products. However, the close association of cellulose, hemicellulose, and lignin limits enzyme accessibility and reduces hydrolysis efficiency. This study evaluates natural deep eutectic solvents (NADES) for pretreating sugarcane bagasse to improve the conversion of cellulose into glucose. Choline chloride (ChCl) was combined with oxalic acid, lactic acid, and glycerol to prepare three NADES systems. The effects of the ChCl molar ratio, bagasse-to-solvent ratio, pretreatment time, and temperature were investigated. Among the three systems, ChCl-oxalic acid produced the greatest improvement in hydrolysis. The selected conditions were a ChCl-to-oxalic acid molar ratio of 1:5, a bagasse-to-solvent ratio of 1:10 (g/g), a pretreatment time of 90 min, and a temperature of 90°C, yielding a glucose concentration of 5.427 mg/mL. NADES pretreatment altered the bagasse surface structure, improving cellulose accessibility and hydrolysis efficiency.
Keywords
sugarcane bagasse lignocellulose deep eutectic solvents pretreatment glucose

References

1.
Abel, G., Bhagwat, P., Amobonye, A., Singh, N. K., Permaul, K., & Pillai, S. (2025). Microwave-assisted deep eutectic solvent pretreatment of macadamia nut shells and pinewood shavings for effective saccharification and bioethanol production. Industrial Crops and Products, 237, 122263. https://doi.org/10.1016/j.indcrop.2025.122263
2.
Abolore, R. S., Jaiswal, S., & Jaiswal, A. K. (2024). Green and sustainable pretreatment methods for cellulose extraction from lignocellulosic biomass and its applications: A review. Carbohydrate Polymer Technologies and Applications, 7, 100396. https://doi.org/10.1016/j.carpta.2023.100396
3.
Del Mar Contreras-Gámez, M., Galán-Martín, Á., Seixas, N., Da Costa Lopes, A. M., Silvestre, A., & Castro, E. (2023). Deep eutectic solvents for improved biomass pretreatment: Current status and future prospective towards sustainable processes. Bioresource Technology, 369, 128396. https://doi.org/10.1016/j.biortech.2022.128396
4.
Liu, Y., Deak, N., Wang, Z., Yu, H., Hameleers, L., Jurak, E., Deuss, P. J., & Barta, K. (2021). Tunable and functional deep eutectic solvents for lignocellulose valorization. Nature Communications, 12(1), 5424. https://doi.org/10.1038/s41467-021-25117-1
5.
Miller, G. L. (1959). Use of Dinitrosalicylic Acid Reagent for Determination of Reducing Sugar. Analytical Chemistry, 31(3), 426-428. https://doi.org/10.1021/ac60147a030
6.
Negi, T., Kumar, A., Sharma, S. K., Rawat, N., Saini, D., Sirohi, R., Prakash, O., Dubey, A., Dutta, A., & Shahi, N. C. (2024). Deep eutectic solvents: Preparation, properties, and food applications. Heliyon, 10(7), e28784. https://doi.org/10.1016/j.heliyon.2024.e28784
7.
Raj, T., & Singh, V. (2024). Natural deep eutectic solvents (NADES) assisted deconstruction of oilcane bagasse for high lipid and sugar recovery. Industrial Crops and Products, 210, 118127. https://doi.org/10.1016/j.indcrop.2024.118127
8.
Rajapakse, H., Raviadaran, R., & Chandran, D. (2025). Deep eutectic solvents for pretreatment of lignocellulosic biomass: Towards circular bioeconomy. Results in Engineering, 26, 105188. https://doi.org/10.1016/j.rineng.2025.105188
9.
Suthar, P., Kaushal, M., Vaidya, D., Thakur, M., Chauhan, P., Angmo, D., Kashyap, S., & Negi, N. (2023). Deep eutectic solvents (DES): An update on the applications in food sectors. Journal of Agriculture and Food Research, 14, 100678. https://doi.org/10.1016/j.jafr.2023.100678
10.
Wang, Q., Chen, J., Jiang, X., Huang, C., Hayashi, J., Meng, X., & Zhou, Y. (2026). Process intensification technology-assisted deep eutectic solvent pretreatment for fractionation of lignocellulosic biomass: A review. Green Chemistry, 28(26), 10807-10833. https://doi.org/10.1039/D6GC01236A