Fucan sulfate (FS) from sea cucumbers possesses linear sequences with repeating units that differ principally in the pattern of sulfation and position of glycosidic linkage. FS from Stichopus herrmanni (ShFS) was preliminarily identified as the relatively simple structure {-3)-L-Fuc_2S-(α1-}n. Herein, mild acid hydrolysis was employed on ShFS to yield 21 oligosaccharides. Analyses on their structures complemented the features of ShFS to refine its spectral signal assignments. Combining with the methylation analysis, unit L-Fuc_2S4S was determined as the micro-component in its intact structure. The irregularity came from minor sulfation on O-4. Temperature and acid concentration were the critical parameters to the depolymerization and formation of oligosaccharides. Meanwhile, a three-step cleavage of the hydrolysis mechanism involving the partial O-2 de-sulfation and preferential cleavage between Fuc_0S and Fuc_2S4S was proposed. Bioactivity assays revealed that the Mw 15–16 kDa conferred the potent anticoagulation via inhibiting the thrombin activity mediated by heparin cofactor II.

来自海参的硫酸岩藻聚糖 (FS) 具有线性序列，其重复单元主要在硫酸化模式和糖苷键的位置上有所不同。海参FS ( Sh FS)初步鉴定为结构相对简单的{-3)-L-Fuc _{2S -(α1-}n。本文对}Sh FS进行温和酸水解得到21个寡糖。结构补充了Sh FS 的特征，以细化其光谱信号分配。结合甲基化分析，单元 L-Fuc _2S4S被确定为在其完整结构中的微组件。不规则性来自 O-4 上的轻微硫酸化。温度和酸浓度是寡糖解聚和形成的关键参数。同时，提出了水解机理的三步裂解，涉及部分O-2脱硫和Fuc _0S和Fuc _2S4S之间的优先裂解。生物活性测定表明，Mw 15-16 kDa 通过抑制由肝素辅因子 II 介导的凝血酶活性而赋予有效的抗凝作用。