Yoon Seon-Joo, Yu Myeong-Ae, Pyun Yu-Ryang, Hwang Jae-Kwan, Chu Djong-Chi, Juneja Lekh Raj, Mourão Paulo A S
Hospital Universítario Clementino Fraga Filho and Departamento de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Thromb Res. 2003;112(3):151-8. doi: 10.1016/j.thromres.2003.10.022.
An acidic polysaccharide with anticoagulant activity was isolated from the edible mushroom Auricularia auricula using water, alkali or acid extracts. The alkali extract showed the highest anticoagulant activity and was thereby further purified using gel filtration chromatography. Specific anticoagulant activity of the purified polysaccharide was 2 IU/mg and its average mass was approximately 160 kDa. The polysaccharide from this species of mushroom contains mainly mannose, glucose, glucuronic acid and xylose but no sulfate esters. Its anticoagulant activity was due to catalysis of thrombin inhibition by antithrombin but not by heparin cofactor II. Inhibition of Factor Xa by antithrombin was not catalyzed by the polysaccharide. The glucuronic acid residues were essential for the anticoagulant action of the mushroom polysaccharide since the activity disappeared after reduction of its carboxyl groups. In ex vivo tests using rats orally fed with the polysaccharide, we observed an inhibitory effect on platelet aggregation as observed with aspirin, a well-known antiplatelet agent. The polysaccharides from these mushrooms may constitute a new source of compounds with action on coagulation, platelet aggregation and, perhaps, on thrombosis.
采用水、碱或酸提取物从食用菌黑木耳中分离出一种具有抗凝活性的酸性多糖。碱提取物显示出最高的抗凝活性，因此进一步通过凝胶过滤色谱法进行纯化。纯化多糖的比抗凝活性为2 IU/mg，其平均质量约为160 kDa。这种蘑菇的多糖主要含有甘露糖、葡萄糖、葡萄糖醛酸和木糖，但不含硫酸酯。其抗凝活性是由于抗凝血酶催化抑制凝血酶，而不是肝素辅因子II。该多糖不催化抗凝血酶对因子Xa的抑制作用。葡萄糖醛酸残基对于蘑菇多糖的抗凝作用至关重要，因为其羧基还原后活性消失。在对口服该多糖的大鼠进行的体外试验中，我们观察到对血小板聚集有抑制作用，这与著名的抗血小板药物阿司匹林的作用相似。这些蘑菇中的多糖可能构成一类对凝血、血小板聚集以及可能对血栓形成有作用的新化合物来源。
