Review: Advances in Magnetic Biochar-Based Cellulase Immobilization Systems for Enhancing Hydrolysis Efficiency in Second-Generation Bioethanol

nessi rahmadani

Abstract

Second-generation bioethanol production utilizes abundant lignocellulosic biomass, such as agricultural residues and woody materials, without competing with food resources. Enzymatic hydrolysis of cellulose into glucose using cellulase is more environmentally friendly than conventional chemical methods; however, the practical application of free cellulase is often limited by low operational stability, sensitivity to temperature and pH fluctuations, and inhibition by compounds generated during biomass pretreatment. To address these challenges, enzyme immobilization on solid supports has been extensively investigated as an effective approach to enhance enzyme stability and enable repeated use. The incorporation of magnetic particles, typically Fe₃O₄, into biochar results in magnetic biochar, which enables rapid separation from the reaction medium using an external magnetic field and facilitates enzyme recovery and reuse. This review summarizes recent studies published between 2020 and 2025 on the application of magnetic biochar as a support for cellulase immobilization to improve the efficiency of lignocellulosic hydrolysis. Reported results demonstrate high enzyme loading capacities (up to approximately 484 mg g⁻¹ biochar), glucose yields exceeding 90%, and retention of more than 80% of enzymatic activity after 5–10 reuse cycles. Overall, magnetic biochar-based immobilization significantly enhances the thermal and pH stability of cellulase, contributing to a more efficient and economically viable saccharification process for second-generation bioethanol production.

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References

H. Mo, J. Qiu, C. Yang, L. Zang, and E. Sakai, “Preparation of chitosan/magnetic porous biochar as support for cellulase immobilization by using glutaraldehyde,” Polymers, vol. 12, no. 11, Art. no. 2672, 2020.

J. Lei et al., “Efficient in situ saccharification of microcrystalline cellulose over immobilized cellulase on magnetic biochar in ionic liquid media,” Chem. Eng. J., vol. 485, Apr. 2024, Art. no. 149990.

H. Wang, Y. Liang, N. Xiao, and Z. Zhu, “The enzymatic hydrolysis of Cardamine violifolia residues with cellulase immobilized on porous biochar via physical and chemical adsorption,” Ind. Crops Prod., vol. 237, 2025, Art. no. 122318.

J. A. John, M. S. Samuel, and E. Selvarajan, “Immobilized cellulase on Fe₃O₄/graphene oxide/chitosan nanocomposite as a magnetically recyclable catalyst for biofuel application,” Fuel, vol. 333, Part 1, Feb. 2023, Art. no. 126364.

A. M. Sulman, V. G. Matveeva, and L. M. Bronstein, “Cellulase immobilization on nanostructured supports for biomass waste processing,” Nanomaterials, vol. 12, no. 21, Art. no. 3796, 2022.

Q. Zhao, T. Xu, X. Song, S. Nie, S.-E. Choi, and C. Si, “Preparation and application in water treatment of magnetic biochar,” Front. Bioeng. Biotechnol., vol. 9, 2021, Art. no. 769667.

M. Bisht, S. K. Thayallath, P. Bharadwaj, G. Franklin, and D. Mondal, “Biomass-derived functional materials as carriers for enzymes: towards sustainable and robust biocatalysts,” Green Chem., vol. 25, pp. 1393–1411, 2023.

C. Xu, S. Tong, L. Sun, and X. Gu, “Cellulase immobilization to enhance enzymatic hydrolysis of lignocellulosic biomass: An all-inclusive review,” Carbohydr. Polym., vol. 321, 2023, Art. no. 121319.

S. Y. Neves et al., “Bioethanol production from lignocellulosic biomass—challenges and solutions,” Molecules, vol. 27, no. 24, Art. no. 8717, 2022.

K. Robak and M. Balcerek, “Review of second generation bioethanol production from residual biomass,” Food Technol. Biotechnol., vol. 56, no. 2, pp. 174–187, 2018.

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