Laboratoire de Génétique, Biodiversité et Valorisation des Bioressources (LR11ES41), University of Monastir, Tunisia.
Unité de Physiologie Fonctionnelle et Valorisation des Bio-Ressources (UR17ES27), Higher Institute of Biotechnology of Beja, University of Jendouba, PB 382, Habib Bourguiba Avenue, 9000, Beja, Tunisia.
Int J Biol Macromol. 2019 Jan;121:1145-1153. doi: 10.1016/j.ijbiomac.2018.10.129. Epub 2018 Oct 16.
Sea cucumber fucoidan is recently endowed with a variety of biological activities. In the present study, we studied the structure and anticoagulant effect of fucoidan from the sea cucumber Holothuria polii (Fuc-Hp). The Fuc-Hp was purified by anion exchange chromatography and its structure was characterized by FT-IR and NMR spectroscopy. Molecular weight measurements were performed by HPSEC-MALLS-dRI. Fuc-Hp anticoagulant activity was measured by activated partial thromboplastin and thrombin times, and by in vitro thrombin inhibition in the presence of antithrombin and heparin cofactor II. The assessment of thrombin generation was investigated using calibrated automated thrombography. Fuc-Hp with a high sulfate content (34.6%) and an average molecular mass of 1376.3 kDa was isolated from H. polii in amount of ~2.7 mg/g dry body wall. Primary structural analysis indicated that Fuc-Hp was mainly composed of a tetrafucose repeating unit branched by glucuronic acid. Fuc-Hp exhibited a high anticoagulant effect mediated essentially by heparin cofactor II and to lesser extent by antithrombin with IC values of 0.16 μg/mL and 0.5 μg/mL, respectively. Overall results showed a high anticoagulant activity of Fuc-Hp, which was attributed to the high sulfate content and abundance of disulfated fucose residues of H. polii fucoidan.
海参岩藻聚糖硫酸酯具有多种生物活性。本研究对糙海参（Holothuria polii）岩藻聚糖硫酸酯（Fuc-Hp）的结构和抗凝活性进行了研究。采用阴离子交换色谱法对 Fuc-Hp 进行分离纯化，采用傅里叶变换红外光谱（FT-IR）和核磁共振波谱（NMR）对其结构进行了表征。通过高效凝胶渗透色谱-多角度激光散射（HPSEC-MALLS-dRI）测定了分子量。采用活化部分凝血活酶时间（APTT）和凝血酶时间（TT）以及在抗凝血酶（AT）和肝素辅因子 II 存在下体外抑制凝血酶活性来评估 Fuc-Hp 的抗凝活性。采用校准自动血栓生成法（calibrated automated thrombography，CAT）评估凝血酶生成情况。从 H. polii 中分离出一种高硫酸化（34.6%）、平均分子量为 1376.3kDa 的 Fuc-Hp，其含量约为 2.7mg/g 干体壁。初步结构分析表明，Fuc-Hp 主要由四糖重复单元组成，这些单元通过葡萄糖醛酸分支。Fuc-Hp 具有很强的抗凝活性，主要通过肝素辅因子 II 介导，其次是抗凝血酶，IC 值分别为 0.16μg/mL 和 0.5μg/mL。综上所述，Fuc-Hp 具有较高的抗凝活性，这归因于 H. polii 岩藻聚糖硫酸酯中硫酸根含量高且富含二硫酸化岩藻糖残基。
