• 关键词：烟曲霉  胞外聚合物  Pb²⁺  吸附

• 基金项目：广州市环保局科技项目(穗计006)

• 熊芬
• 1. 华南理工大学环境科学与工程学院, 广州 510006; 2. 工业聚集区污染控制与生态修复教育部重点实验室, 广州 510006

• 胡勇有
• 1. 华南理工大学环境科学与工程学院, 广州 510006; 2. 工业聚集区污染控制与生态修复教育部重点实验室, 广州 510006

• 银玉容
• 1. 华南理工大学环境科学与工程学院, 广州 510006; 2. 工业聚集区污染控制与生态修复教育部重点实验室, 广州 510006

• 摘要：采用阳离子交换树脂(CER)法提取了烟曲霉胞外聚合物(EPS),并分析了其生物化学成分.同时,考察了烟曲霉EPS对重金属离子Pb²⁺的去除效果,探讨了其生物吸附机理和动力学特性.结果表明,CER法提取的烟曲霉EPS多糖含量较高,对细胞破坏程度较小.烟曲霉EPS吸附Pb²⁺的平衡时间约为3h,最佳吸附pH为6.5,吸附平衡时Pb²⁺去除率为73.48%.烟曲霉EPS对Pb²⁺的吸附平衡均能较好地用Langmuir模型和Freundlich模型来描述,而且更适用Langmuir模型,最大吸附量qm为32.22mg·g^-1.烟曲霉EPS的FTIR分析结果表明,多聚糖中的羟基、羧基和C—O—C等是与Pb²⁺发生了作用的基团,而其中蛋白质的作用不明显.

• Abstract：CER extraction was used to extract extracellular polymeric substances from Aspergillus fumigatus.The biochemical composition of the EPS was determined.The adsorption of Pb²⁺ by the EPS was investigated and the equilibrium and the mechanism of biosorption of Pb²⁺ by EPS are discussed.The results showed that the CER process extracted high amounts of the EPS carbohydrate with hardly any cell lysis.The biosorption equilibrium time was about 3 hours.At pH 6.5,the lead removal efficiency could reach 73.48%.Both the Langmuir isotherm and Freundlich isotherm models could describe the biosorption equilibrium well,but the Langmuir isotherm fit better.The maximum uptake capacity of lead was estimated to be 32.22 mg·g^-1 EPS.Analysis of FTIR spectra demonstrated that hydroxyl,carboxyl and C—O—C groups of the polysaccharide were the main functional groups in the reaction between Pb²⁺,and the binding capacity of protein to Pb²⁺ was weak.

• Key words：aspergillus fumigatus  extracellular polymeric substances(EPS)  Pb²⁺  biosorption

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