Preparation and characterization of various chitin-glucan complexes derived from white button mushroom using a deep eutectic solvent-based ecofriendly method

• Published in: International journal of biological macromolecules 2021-02, Vol.169, p.122-129
• Main Authors: Kim, Hireem, Kang, Seulgi, Li, Ke, Jung, Dasom, Park, Keunbae, Lee, Jeongmi
• Format: Article
• Language: English
• Subjects: Agaricus - chemistry; Agaricus - enzymology; Agaricus - isolation & purification; beta-Glucans; Chitin - chemistry; Chitin - isolation & purification; Chitin-glucan complex; Choline - chemistry; Deep eutectic solvent; Glucans - chemistry; Glucans - isolation & purification; Mushroom; Solvents - chemistry
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2020.12.081

Deep eutectic solvents (DESs) have gained great interests as ecofriendly and safe solvents in diverse areas. Herein, various chitin-glucan complexes (CGCs) were prepared from white button mushroom (Agaricus bisporus) using DESs. Ultrasonication of mushroom in five DESs yielded two types of CGCs from each DES, one from the DES-insoluble residue (DES_P) and another from the DES-soluble extract (DES_S). The ten resulting CGCs with varying chitin-to-β-glucan ratios were compared with alkali-insoluble matter (AIM), chemically prepared using NaOH. BU_S and BU_P, prepared using BU comprising betaine and urea, were obtained in the highest yields with reasonably low protein and mineral contents. Despite different acetylation degrees (77.3% and 57.3%, respectively), BU_S and BU_P both degraded at 318 °C and showed remarkably low crystallinity (32.0% and 37.0% for BU_S and BU_P, respectively) compared to AIM, commercial chitin, and the reported CGCs. The surface of BU_S and BU_P was very porous and rough compared with AIM as a result of reduced H-bonds and lowered crystallinity. The DES-based method can potentially enable the preparation of advanced biomaterials from mushrooms under mild and ecofriendly conditions. [Display omitted] •A new, green method to prepare various CGCs from mushrooms is presented.•One DES can provide two types of CGCs with different composition and properties.•Numerous CGCs free from potential allergens can be produced by applying various DESs.•The CGC preparation method is simple and involves mild and ecofriendly conditions.•CGCs prepared using the DES-based method show remarkably low crystallinity.