摘要
通过溶液培养小球藻Pb2+暴露实验分析小球藻对Pb的富集以及亚细胞分布情况。结果表明:小球藻对Pb的富集总量随暴露浓度、暴露时间的增加而增加。运用差速离心法研究了小球藻中Pb在亚细胞中的分布,热力学实验与动力学实验的细胞分布结果均表明含细胞壁等残渣部分(组分I)中Pb的浓度远高于含细胞核、叶绿体、线粒体等细胞器膜系统(组分II)和可溶蛋白等细胞溶质部分(组分III)中Pb的浓度。采用动力学模型与等温线方程对实验数据进行拟合,结果表明小球藻对于Pb2+的生物吸附过程适宜用Elovich方程和二级吸附速率方程来描述,生物吸附平衡可用Langmiur等温式和Freundlich等温式来描述,小球藻对于Pb2+的生物吸附为非均相的扩散过程。
Through solution culture the exposure of Chlorella pyrenoidosa to Pb2＋ was carried to investigate the adsorption and the subcellular fractionation of Pb in Chlorella.Results showed that the total absorption capacity increased with the increase of both exposure concentration and exposure time.The differential centrifugation technique was used to analyze the subcellular fractionation of Pb in Chlorella.The subcellular fractionation of Pb in thermodynamic experiments and kinetic experiments showed that： Pb content of the residues containing the cell wall,ect（fraction I） was higher than that of the organelle membrane system containing nucleus,chloroplast,mitochondria,ect（fraction II） and the cytosolic fraction containing protein,ect;（fraction III）.All the data were fitted using several models.The biosorption kinetics data could be fitted using Elovich equation and second-order kinetics equation.The biosorption equilibrium could be described well using Langmiur and Freundlich adsorption isotherms.Biosorption of Pb2＋ by Chlorella was a process of unsymmetrical phase diffusion.
出处
《环境科技》
2010年第6期1-3,7,共4页
Environmental Science and Technology
基金
国家自然科学基金(90913012)
973计划(2009CB421601)
关键词
吸附
亚细胞分布
铅离子
小球藻
Adsorption
Subcellular fractionation
Pb2＋
Chlorella
