College of Food Science, Shenyang Agricultural University, Shenyang 110866, China.
College of Food Science, Shenyang Agricultural University, Shenyang 110866, China.
Carbohydr Polym. 2022 Sep 1;291:119598. doi: 10.1016/j.carbpol.2022.119598. Epub 2022 May 10.
Synergistic degradation of chitosan by discrete ultrasonic and HO was investigated. The effects of ultrasonic time, ultrasonic power, chitosan concentration, and HO concentration were evaluated. The results revealed that ultrasonic power, HO concentration and ultrasonic time were positively correlated with degradation rate, while chitosan concentration was negative. The results of degradation kinetics revealed that the synergistic degradation process was consistent with the first-order reaction. Changes of characterization of chitosan were analyzed by FTIR, C NMR, XRD, SEM, and AFM analysis. The results indicated that the synergistic degradation did not destroy the pyranose ring. The crystal structure of degraded chitosan was destroyed, and the molecular conformation changed significantly. The antioxidant activity of the original and degraded chitosan was determined by DPPH and reducing power assays. The degraded chitosan had higher antioxidant activity. All results showed that the synergistic degradation of discrete ultrasound and HO was a feasible method for large-scale low molecular weight chitosan production.
研究了离散超声和 HO 协同降解壳聚糖。考察了超声时间、超声功率、壳聚糖浓度和 HO 浓度的影响。结果表明，超声功率、HO 浓度和超声时间与降解速率呈正相关，而壳聚糖浓度则呈负相关。降解动力学结果表明，协同降解过程符合一级反应。通过傅里叶变换红外光谱（FTIR）、碳核磁共振（C NMR）、X 射线衍射（XRD）、扫描电子显微镜（SEM）和原子力显微镜（AFM）分析了壳聚糖的结构变化。结果表明，协同降解并未破坏吡喃糖环。降解壳聚糖的晶体结构被破坏，分子构象发生了显著变化。通过 DPPH 和还原力测定法测定了原始壳聚糖和降解壳聚糖的抗氧化活性。降解壳聚糖具有更高的抗氧化活性。所有结果表明，离散超声和 HO 的协同降解是一种大规模生产低分子量壳聚糖的可行方法。
