Key Laboratory of Refrigeration and Conditioning Aquatic Products Processing, Ministry of Agriculture and Rural Affairs, Xiamen 361022, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China.
School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China.
Int J Biol Macromol. 2023 Nov 1;251:126296. doi: 10.1016/j.ijbiomac.2023.126296. Epub 2023 Aug 11.
This study targeted the sustainable utilization of chitin and chitosan from crayfish shell waste, and further depolymerization of the recovered products in one step through synergy between microwaves and graphene oxide, aiming for the monosaccharides, 5-hydroxymethylfurfural and other high-value products. The results indicated that graphene oxide was more effective than graphene in enhancing the microwave absorption properties of the system, which is contrary to the parameters of their dielectric properties. The heating rate was increased by 0.37 K/s and 0.26 K/s when graphene oxide was introduced into the chitin and chitosan depolymerization systems, respectively, at a microwave power of 5 W/g. The mechanism underlying the impact of graphene oxide on chitin and chitosan under a microwave field was proposed by analyzing the variations in the depolymerization products of chitin and chitosan systems under different reaction conditions, including holding time, catalyst content, solvent content, and reaction temperature. Furthermore, the recovered graphene oxide exhibited delamination upon redispersion in water, which was not observed in the initial samples. The infrared spectra and scanning electron microscopy results suggest that the catalytic reaction is associated with oxygen-containing functional groups. This study demonstrated the synergistic effect of microwaves and graphene oxide on the depolymerization of chitin and chitosan, and the ability to achieve rapid one-step depolymerization in an acid/alkali-free solvent, which provides a green and promising development for the degradation of carbohydrate macromolecules in crustacean solid waste.
本研究针对从小龙虾壳废弃物中可持续利用甲壳素和壳聚糖，并通过微波和氧化石墨烯协同作用一步实现回收产物的解聚，旨在获得单糖、5-羟甲基糠醛等高价值产物。结果表明，氧化石墨烯比石墨烯更能增强体系的微波吸收特性，这与它们介电性能的参数相反。在微波功率为 5 W/g 时，分别向甲壳素和壳聚糖解聚体系中引入氧化石墨烯，加热速率分别提高了 0.37 K/s 和 0.26 K/s。通过分析不同反应条件下甲壳素和壳聚糖体系解聚产物的变化，提出了氧化石墨烯在微波场下对甲壳素和壳聚糖影响的机理，包括保持时间、催化剂含量、溶剂含量和反应温度。此外，回收的氧化石墨烯在重新分散于水中时会发生层离，而初始样品中则没有观察到这种情况。红外光谱和扫描电子显微镜结果表明，催化反应与含氧官能团有关。本研究证明了微波和氧化石墨烯对甲壳素和壳聚糖解聚的协同作用，以及在无酸/碱性溶剂中实现快速一步解聚的能力，为甲壳类固体废弃物中碳水化合物大分子的降解提供了一种绿色且有前景的发展方向。
