二氧化氯对球形棕囊藻叶绿素a、蛋白质、DNA含量的影响

Effects of Chlorine Dioxide on Contents of Chlorophyll a, Proteins and DNA in Phaeocystis globosa

摘要:

分析了二氧化氯（1.0、1.5、2.0、2.5 mg L^-1,作用96 h;2.5、6.0、8.0、16.0 mg L^-1，作用60 min）对球形棕囊藻叶绿素a、蛋白质含量、氨基酸组成、核酸含量的影响,用透视电镜对二氧化氯（0.5 mg L^-1,0.8 mg L^-1）作用24 h后藻细胞形态的变化进行了观察，以探讨二氧化氯去除赤潮藻的机理。结果表明,二氧化氯对球形棕囊藻叶绿素a、蛋白质、DNA的含量均有影响.实验各组（1.0-2.5 mg L^-1,2.5-16.0 mg L^-1）球形棕囊藻的叶绿素a、蛋白质、DNA的含量均显著低于对照。二氧化氯浓度超过2 mg L^-1时，球形棕囊藻的叶绿素a、蛋白质、DNA的含量持续降低，氨基酸相对含量发生明显变化；半胱氨酸、酪氨酸和赖氨酸等的相对含量明显降低，而组氨酸、缬氨酸和苯丙氨酸则明显增加。当二氧化氯（2.5-16.0 mg L^-1）作用3 min后,DNA漏出率在13%-18%之间；电镜观察发现，二氧化氯可使细胞膜破损，引起内容物外泄.这些结果显示，二氧化氯能以单分子形式进入细胞，引起叶绿素、蛋白质结构的变化，并破坏藻细胞膜系统，最终导致藻细胞死亡。

Abstract:

Following the low dose of chlorine dioxide （1.0, 1.5,2.0,2.5 mg L^-1） treatment of Phaeocystis globosa for 96 h and the high dose （2.5,6.0,8.0, 16.0 mg L^-1） treatment for 60 min, the contents of chlorophyll a, proteins, amino acids and DNA in cells were determined. Meanwhile, changes in cell morphology after 24 h treatment of chlorine dioxide （0.5 mg L^-1, 0.8 mg L-^-1） was observed by transmission electron microscope. Contents of chlorophyll a, proteins and DNA in the treated P. globosa were lower than those in controls. In the present of chlorine dioxide over 2.0 mg L^-1, chlorophyll a, proteins, DNA in content and cysteine, tyrosine, lysine in relative percentage remarkably decreased, whereas histidine, valine and phenylalanine in relative percentage increased. The leakage rate of DNA was in the range of 13%-18% after treated with chlorine dioxide of 2.5-16.0 mg L^-1 for 3 min. We observed that the substance damaged the cell membranes, causing the leakage of cellular content. These results suggested that chlorine dioxide might deform chlorophyll a and proteins in P. globosa by single molecular diffusion, damage the cell membrane system by lipid peroxidation, and eventually led to the death of cells.