The Tremella fuciformis Berk polysaccharides (TP) have significant cytokine‐stimulating activity and low oral bioavailability owing to their large molecular volume. Identifying and studying the smallest active structure of TP can potentially be beneficial for further utilization and research, therefore, TP was hydrolyzed and fractionated to obtain its (1→3)‐mannan backbone fragments. The fragments were further isolated by ion‐exchange resin, ultrafiltration, gel, and HPLC chromatography, and three oligosaccharide fractions, named TL4‐1, TL4‐2, TL4‐3, were obtained. According to the determination of their physicochemical properties, they were composed of Man, and after methylation analysis they were mainly characterized as (1→3)‐mannan oligosaccharides with a straight chain. TL4‐1 contained di‐, trisaccharides, TL4‐2 included tetra‐, penta‐saccharides, and TL4‐3 was made up of hex‐, hepta‐, octa‐saccharides, according to LC‐ESI/MS analysis. Cytokine stimulation experiments showed that the degree of polymerization (DP) should be more than six to maintain the activity of mannosan. Therefore, the smallest active unit of oligo‐mannose was determined.

中文翻译：

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银耳银耳中寡糖的制备，表征和细胞因子刺激活性。

将银耳伯克多糖（TP）由于具有大分子体积，因此具有显着的细胞因子刺激活性和较低的口服生物利用度。鉴定和研究TP的最小活性结构可能有益于进一步的利用和研究，因此，将TP水解并分馏以获得其（1→3）-甘露聚糖骨架片段。通过离子交换树脂，超滤，凝胶和HPLC色谱进一步分离碎片，获得了三个寡糖级分，分别为TL4-1，TL4-2，TL4-3。根据其理化性质的测定，它们是由Man组成，经甲基化分析后，它们的主要特征是具有直链的（1→3）-甘露聚糖。TL4-1包含二糖，三糖，TL4-2包含四糖，五糖，根据LC-ESI / MS分析，TL4-3由六，七，八糖组成。细胞因子刺激实验表明，聚合度（DP）应大于六以维持甘露聚糖的活性。因此，确定了最小的低聚甘露糖活性单位。