CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, No. 7 Nanhai Road, Qingdao 266071, China.
Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China.
Molecules. 2021 Apr 28;26(9):2563. doi: 10.3390/molecules26092563.
In this paper, chitooligosaccharides in different salt forms, such as chitooligosaccharide lactate, citrate, adipate, etc., were prepared by the microwave method. They were characterized by SEM, FTIR, NMR, etc., and the nitric oxide (NO) expression was determined in RAW 264.7 cells. The results showed that pure chitooligosaccharide was an irregular spherical shape with rough surface, and its different salt type products are amorphous solid with different honeycomb sizes. In addition to the characteristic absorption peaks of chitooligosaccharides, in FTIR, the characteristic absorption of carboxyl group, methylene group, and aromatic group in corresponding acid appeared. The characteristic absorption peaks of carbon in carboxyl group, hydrogen and carbon in methyl, methylene group, and aromatic group in corresponding acid also appeared in NMR. Therefore, the sugar ring structure and linking mode of chitooligosaccharides did not change after salt formation of chitooligosaccharides. Different salt chitooligosaccharides are completely different in promoting NO secretion by macrophages, and pure chitooligosaccharides are the best.
本文采用微波法制备了不同盐形式的壳寡糖，如壳寡糖乳酸盐、柠檬酸盐、己二酸盐等。采用 SEM、FTIR、NMR 等对其进行了表征，并测定了其在 RAW 264.7 细胞中一氧化氮（NO）的表达。结果表明，纯壳寡糖呈不规则球形，表面粗糙，其不同盐型产品为无定形固体，具有不同的蜂窝尺寸。除了壳寡糖的特征吸收峰外，在 FTIR 中，相应酸中羧基、亚甲基和芳基的特征吸收也出现了。在 NMR 中，相应酸中羧基的碳、氢和碳、亚甲基中的碳以及芳基中的碳的特征吸收峰也出现了。因此，壳寡糖形成盐后，糖环结构和连接方式没有发生变化。不同盐的壳寡糖在促进巨噬细胞分泌 NO 方面完全不同，纯壳寡糖效果最好。
