School of Food Science and Technology, National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, PR China.
School of Food Science and Technology, National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, PR China; National & Local Joint Engineering Laboratory for Marine Bioactive Polysaccharide Development and Application, Dalian Polytechnic University, Dalian 116034, PR China.
Int J Biol Macromol. 2023 Feb 28;229:413-421. doi: 10.1016/j.ijbiomac.2022.12.307. Epub 2022 Dec 29.
Fucoidan is a highly sulfated polysaccharide with a wide range of bioactivities, including anti-pathogenic activity. However, the relationship between structure and activity of fucoidan in inhibiting pathogen infections remains unclear. Here, different-molecular-weight fucoidans were prepared by photocatalytic degradation followed by membrane ultrafiltration, and their chemical structures and anti-pathogenic microbiota activity were compared. Results showed that photocatalytic degradation could effectively degrade fucoidan while its structure block and sulfate groups were not destroyed obviously. Fucoidan (90.8 kDa) of 5 mg/mL could inhibit the growth of S. aureus, S. typhimurium and E. coli, but its degradation products, Dfuc1 (19.2 kDa) and Dfuc2 (5.5 kDa), demonstrated lower inhibitory effect. In addition, compared to Dfuc1 and Dfuc2, fucoidan showed stronger capability to prevent the adhesion of S. aureus, L. monocytogenes, V. parahaemolyticus and S. typhimurium to HT-29 cells. Moreover, the inhibitory effect against SARS-CoV-2 and the binding activity to S protein were also positively correlated to molecular weight. These results indicate that natural fucoidan with higher molecular weight are more effective to inhibit these pathogenic bacteria and SARS-CoV-2, providing a better understanding of the relationship between structure and activity of fucoidan against pathogenic microbiota.
岩藻聚糖是一种具有广泛生物活性的高度硫酸化多糖，包括抗病原活性。然而，岩藻聚糖抑制病原感染的结构与活性关系尚不清楚。本研究采用光催化降解结合膜超滤的方法制备了不同分子量的岩藻聚糖，并对其化学结构和抗病原微生物活性进行了比较。结果表明，光催化降解可以有效地降解岩藻聚糖，而其结构块和硫酸基团并没有明显破坏。浓度为 5mg/mL 的岩藻聚糖（90.8 kDa）可以抑制金黄色葡萄球菌、鼠伤寒沙门氏菌和大肠杆菌的生长，但它的降解产物 Dfuc1（19.2 kDa）和 Dfuc2（5.5 kDa）的抑制效果较低。此外，与 Dfuc1 和 Dfuc2 相比，岩藻聚糖对金黄色葡萄球菌、单核细胞增生李斯特菌、副溶血性弧菌和鼠伤寒沙门氏菌与 HT-29 细胞黏附的抑制能力更强。此外，对 SARS-CoV-2 的抑制作用和与 S 蛋白的结合活性也与分子量呈正相关。这些结果表明，天然岩藻聚糖具有更高的分子量，更有效地抑制这些病原菌和 SARS-CoV-2，为深入了解岩藻聚糖对抗病原微生物的结构与活性关系提供了依据。
