锗对两种微藻的毒性及其在细胞中的累积

TOXICITY AND BIOACCUMULATION OF GERMANIUM IN TWO MICROALGAE Spirulina platensis AND Dunaliella salina

钝顶螺旋藻Spirulina platensis(Cyanophyceae)和盐生杜氏藻Dunaliellasalina(Chlorophyceae)暴露在不同浓度锗的培养液中。研究了锗对它们的毒性及锗在藻细胞中的累积。结果表明 ,锗对S.platensis的毒性较D.salina大。在培养浓度范围内 ,S.platensis中的总锗含量与培养介质中的锗含量关系不大。锗在S.platensis中的分布较均匀且呈剂量效应 ,在D.salina中 ,总锗含量随着培养液中锗含量的增加而增加。锗在细胞中的分布以氨基酸 碳水化合物和蛋白质中为主 ,脂类中含量则较低。上述差异反映了藻类在生理特性上的不同。研究表明 ,当藻类暴露在含锗介质中时 ,可吸收累积一定量的锗并结合到细胞内的大分子物质中 ,从而达到降低锗毒性的作用。

The toxicity and bioaccumulation of germanium were investigated in two microalgae: Spirulina platensis and Dunaliella salina in culture. Germanium was more toxic to S.platensis than to D.salina.Lower concentrations of germanium within the culture germanium concentration, the amount of germanium absorbed by S.platensis did not increase with the added germanium concentration,and germanium well distributed in cells and showed dose effect. In D.salina, total germanium concentration increased with the added germanium concentraion,most of germanium was associated with proteins and amino acids-dissolved carbohydarte,which may represent a form of storage of detoxication of germanium.These results suggest that rsponse of algae to germanium toxicity is different, which reflects a physiological difference among algae.