In this study, a glucuronoxylomannan named TAP-3 was obtained from high-value Tremella aurantialba Bandoni et Zang. Physicochemical analysis revealed that TAP-3, which had a molecular weight of ∼624 kDa, mainly consisted of D-mannose (Man), D-xylose (Xyl), and D-glucuronic acid (GlcA) in a molar ratio of 3.0: 1.0: 1.0. Structural analyses of its depolymerized fragments clarified that TAP-3 contained a (1→3) and (1→2)-linked α-Manp backbone, side chains formed by β-Xylp and β-GlcpA linked to the C-2 position of α-Manp, and acetyl groups connected to the sixth hydroxyl positions of Manp. TAP-3 showed marked immune enhancement activity, promoting NO, IL-1β and TNF-α secretion from macrophages. The critical membrane receptor of TAP-3 was identified to be TLR4, and the chain length was essential for its immunoregulatory activity. These findings expand knowledge of the structural types of glucuronoxylomannan and illustrate its biological activity as an immunopotentiator.

在这项研究中，从高价值的银耳白兰地Bandoni et Zang获得了一种名为TAP-3的葡糖醛酸氧甘露聚糖。物理化学分析表明，TAP-3的分子量约为624 kDa，主要由D-甘露糖（Man），D-木糖（Xyl）和D-葡萄糖醛酸（GlcA）组成，摩尔比为3.0： 1.0：1.0。其解聚片段的结构分析澄清，TAP-3含有（1→3）和（1→2） -连接的α-曼p骨架，由β-的Xyl形成侧链p和β-GLC p甲链接到Ç -2α-曼的位置p，以及连接到人的第六羟基位置上的乙酰基p。TAP-3具有明显的免疫增强活性，可促进巨噬细胞分泌NO，IL-1β和TNF-α。TAP-3的关键膜受体被鉴定为TLR4，其链长对其免疫调节活性至关重要。这些发现扩展了对葡糖醛酸氧甘露聚糖的结构类型的了解，并说明了其作为免疫增强剂的生物学活性。