杜氏盐藻(Dunaliella salina)对重金属铜胁迫的生理响应

摘要

将不同质量浓度的CuCl2溶液添加到培养基中, 研究重金属铜对杜氏盐藻 (Dunaliella salina) 胁迫的生理响应.分别用不同质量浓度的CuCl2溶液培养盐藻, 检测盐藻的光合色素、可溶性多糖、蛋白质、SOD及MDA质量浓度的变化.结果显示, 铜可抑制盐藻细胞的生长, 且呈剂量-效应关系, 72 h的EC50为9. 55 mg/L.随着铜质量浓度的增加, 各质量浓度组盐藻细胞内叶绿素a、b、总叶绿素、类胡萝卜素、多糖和蛋白质质量浓度均显著性降低 (P ＜0. 05或P ＜0. 01).铜可导致盐藻细胞氧化损伤, 随着铜质量浓度的升高, SOD活力先升高后降低, MDA质量浓度升高.表明铜可以抑制盐藻细胞内光合色素、多糖和蛋白质的合成.盐藻对铜胁迫的响应机制可能是通过抗氧化防御系统.%To study the physiological response of heavy metal copper stress on Dunaliella salina. Dunaliella salina was cultured with different concentrations of CuCl2 solution. The photosynthetic pigments, soluble polysaccharides, protein, SOD and MDA contents were determined. The results showed that copper could inhibit the growth of D. salina cells in a dosedependent manner. The EC50 at 72 h was 9. 55 mg/L. With the increase of copper concentration, the contents of chlorophyll a, b, total chlorophyll, carotenoid, polysaccharides and protein significantly decreased (P ＜ 0. 05 or P ＜ 0. 01). Copper could cause oxidative damage of D. salina cells. In addition, with the increase of copper concentration, SOD activity increased first and then decreased, and MDA content increased. Copper could inhibit the synthesis of photosynthetic pigments, polysaccharides and proteins in D. salina. The mechanism of D. salina in response to copper may be the antioxidant defense system.