一种棕囊藻的形态特征与毒素分析

MORPHOLOGICAL CHARACTERISTICS AND TOXINS OF PHAEOCYSTIS CF.POUCHETII (PRYMNESIOPHYCEAE)

于1997年11月，在广东省汕头地区饶平县海面采集棕囊藻，采用显微观察和光谱分析方法，进行形态特征与毒素结构的研究。结果表明，该种藻具有两种不同的藻体形态：一种是不运动的球形群体（直径0．1一3cm），外具胶质被，群体内的细胞有近千至数万个，每个细胞（直径3－7．5μm）有2－3个黄褐色的叶绿体；另一种是游动的单细胞，具有两根几乎等长的鞭毛和一根短的定鞭丝（也称为附着鞭毛或触丝），常呈球形。将反复冻融或冷冻干燥的藻细胞经有机溶剂提取，用新鲜牛血球测定显示出具有强的溶血毒素特性。溶血毒素经硅胶柱层析纯化，被分成5个组分，对溶血活性高的组分进行化学结构测定的结果表明，该藻溶血毒素是一个以1’-O-十七碳二烯酸基-3’-O-)6-O-α-D-吡喃半乳糖-μ-D-吡喃半乳糖基)-甘油为主的糖脂混合物。

A heavy algal bloom of harmful and toxic Phaeocystis cf pouchetii occurred in the coastal water of Southeast China in the autumn of 1997. Two different morphotypes of Phaeocyslis cf pouchetii were observed. one was nonmotile spherical colonies with a multitude of cells (103-104) disposed around the periphery and surrounded by a gelatinous covering. The colonies varied in size from 10mm to 30mm in diameter. Cells in the colony measured 3-7.5μm and had 2-3 chloroplastS. The other was mohle spherical single cells, each possessing two almost equal flagella and a shoft haptonema. Toxins were obtained from Phaeocystis cf pouchetii cells through lyophilization and extraction with various orgboc solvents and assayed in terms of their achvity on bovine erythrocytes. The results show that Phaeocystis cf pouchetii connined hemolysin. The hemolysin was separated into five components by silicagel column chromatography, arnong which the most potent component was identified as a mixture of glycolipids, with the major constituent of 1'O-heptadecadienoyl-3 '-O-(6-O -α-D-galactopyranosy-β-D-Galactopyranosyl)Glycerol.