Abstract：
This study aimed to isolate Ulva pertusa polysaccharide (UPP), which elicits anti-inflammatory bowel disease (IBD) effects, from the Korea seaweed U. pertusa and identify its structure. Firstly, UPP was isolated from U. pertusa using hydrothermal extraction and ethanol precipitation. UPP is a novel polysaccharide that exhibits unique structural features such as 3-sulfated rhamnose, glucuronic acid, iduronic acid, and 3-sulfated xylose, which are repeated in 1,4-glycosidic bonds. Prophylactic oral administration of UPP in mice with dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) suppressed the levels of inflammatory cytokines and MAPK- and NF-κB-related factors in the serum and colon tissue. Tight junction (TJ)-related factors such as occludin, claudin-1, and mucin were effectively augmented by UPP in the colon tissue. In addition, UPP administration prevented the DSS treatment-led cecal short chain fatty acid imbalance, and this effect was most evident for propionic acid. In conclusion, UPP isolated from the Korean U. pertusa demonstrates potent anti-IBD activity. Characterization of this ulvan revealed its unique structure. Moreover, its efficacy may be associated with its anti-inflammatory effects and regulation of gut microbiota and TJ proteins. Thus, this study provides new insights into the biological effects of UPP in IBD.
摘要：
本研究旨在分离百日咳乌龟多糖(UPP),这引发了抗炎肠病（IBD）的作用，从韩国海藻U.pertusa和确定其结构。首先,使用水热提取和乙醇沉淀从百日咳杆菌中分离出UPP。UPP是一种新型多糖，具有独特的结构特征，如3-硫酸化鼠李糖，葡萄糖醛酸，艾杜糖醛酸，和3-硫酸化木糖，以1,4-糖苷键重复。在葡聚糖硫酸钠（DSS）诱导的溃疡性结肠炎（UC）小鼠中预防性口服UPP抑制了血清和结肠组织中炎性细胞因子以及MAPK和NF-κB相关因子的水平。紧密连接（TJ）相关因素，如闭塞蛋白，结肠组织中的UPP有效地增强了claudin-1和粘蛋白。此外,UPP给药防止DSS治疗导致的盲肠短链脂肪酸失衡，这种效果对于丙酸最为明显。总之,从韩国百日葵分离的UPP表现出有效的抗IBD活性。这种ulvan的特征揭示了其独特的结构。此外，其疗效可能与其抗炎作用以及对肠道菌群和TJ蛋白的调节有关.因此，本研究为UPP在IBD中的生物学效应提供了新的见解。
