总状蕨藻盾叶变种寡糖的酶解制备及其免疫调节活性的作用机制  

Enzymatic Preparation and Immunomodulatory Mechanism of Oligosaccharide from Caulerpa racemosa var.peltate

作　　者：曾瑾子 林倩敏 许静宜 徐宝军[2] 黄耀南 黄日明 ZENG Jinzi;LIN Qianmin;XU Jingyi;XU Baojun;Io Nam WONG;HUANG Riming(College of Food Science,South China Agricultural University,Guangzhou 510642,China;Department of Life Science,BNU-HKBU United International College,Zhuhai 519087,China;Faculty of Medicine,Macao University of Science and Technology,Macao 999078,China)

机构地区：[1]华南农业大学食品学院,广东广州510642 [2]北京师范大学-香港浸会大学联合国际学院生命科学系,广东珠海519087 [3]澳门科技大学医学院,中国澳门999078

出　　处：《食品科学》2024年第17期42-51,共10页Food Science

基　　金：国家自然科学基金国际(地区)合作与交流项目(32161160304);澳门科学技术发展基金与国家自然科学基金委员会联合资助项目(0069/2021/AFJ)。

摘　　要：将总状蕨藻盾叶变种多糖经乳糖酶酶解、膜过滤、透析和冻干制备获得总状蕨藻盾叶变种寡糖(Caulerpa racemosa var.peltate oligosaccharide,CRVO-G),测定CRVO-G的相对分子质量与单糖组成,评价CRVO-G的免疫调节活性,并对其作用机制展开研究。结果显示,CRVO-G主要是由相对分子质量分别为617.115、621.081和995.368的2种四糖和1种六糖组成的寡糖混合物,主要由半乳糖(51.0%)、甘露糖(21.3%)、葡萄糖(11.5%)、木糖(6.5%)、鼠李糖(2.3%)、葡萄糖醛酸(2.0%)、盐酸氨基葡萄糖(1.8%)、岩藻糖(0.8%)、盐酸氨基半乳糖(0.7%)、半乳糖醛酸(0.7%)、甘露糖醛酸(0.7%)和阿拉伯糖(0.6%)组成。此外,CRVO-G具有良好的免疫调节活性,能促进一氧化氮(NO)和免疫因子的释放,如白细胞介素-1β、白细胞介素-6和肿瘤坏死因子-α。代谢组学和蛋白免疫印迹结果表明,CRVO-G可以促进巨噬细胞花生四烯酸代谢通路中血栓素A2和15-酮前列腺素F2α的合成,提高环氧合酶-2(cyclooxygenase-2,COX-2)、诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)和核因子κB(nuclear factorκB,NF-κB)的磷酸化蛋白的表达水平。研究表明,在巨噬细胞RAW264.7细胞中CRVO-G通过NF-κB/iNOS/COX-2途径发挥免疫调节作用。In this study,oligosaccharide from Caulerpa racemosa var.peltate(CRVO-G)was prepared by sequential enzymatic hydrolysis with lactase,membrane filtration,dialysis,and freeze-drying,and the relative molecular mass and monosaccharide composition of CRVO-G were measured.Meanwhile,the immunoregulatory activity of CRVO-G was evaluated and its mechanism of action was studied.The results showed that CRVO-G was a mixture of two tetrasaccharides and one hexasaccharide with relative molecular masses of 617.115,621.081,and 995.368,and was mainly composed of galactose(51.0%),mannose(21.3%),glucose(11.5%),xylose(6.5%),rhamnose(2.3%),glucuronic acid(2.0%),glucosamine hydrochloride(1.8%),fucose(0.8%),glucosamine hydrochloride(0.7%),galacturonic acid(0.7%),mannuronic acid(0.7%),and arabinose(0.6%).In addition,CRVO-G had good immunomodulatory activity,as manifested by increased release of nitric oxide and cytokines(interleukin(IL)-1β,IL-6 and tumor necrosis factor(TNF)-α).The results of metabolomics analysis and Western blot showed that CRVO-G could promote the synthesis of thromboxane A2(TXA2)and 15-keto prostaglandin F2α(15-keto-PGF2α)in the arachidonic acid pathway of macrophages,and increase the expression levels of cyclooxygenase-2(COX-2),inducible nitric oxide synthase(iNOS),and the phosphorylation of nuclear factorκB(NF-κB).In summary,CRVO-G exerts immunomodulatory effects by the NF-κB/iNOS/COX-2 pathway in RAW264.7 macrophages.

关 键 词：总状蕨藻盾叶变种 寡糖 酶解 免疫调节 分子机制 

分 类 号：TS201.2[轻工技术与工程—食品科学] TS201.4[轻工技术与工程—食品科学与工程]