Lei W, Chua H, Lo W H, Yu P H, Zhao Y G, Wong P K
Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Hong Kong.
Appl Biochem Biotechnol. 2000 Spring;84-86:1113-26. doi: 10.1385/abab:84-86:1-9:1113.
The sorption and desorption of copper (II) (Cu[II]) ions from the wastewater by magnetite-immobilized cells of Pseudomonas putida 5-x with acidic pretreatment were studied. Pretreating cells with 0.6 N HCl was found to enhance greatly the adsorption capacity of biomass up to 85.6 mg/g and had no significant effect on the loss of P. putida 5-x cells during biosorbent pretreatment. The biosorption capacity to Cu2+ of magnetite-immobilized cells of P. putida 5-x harvested during various growth phases was also investigated. The experimental results illustrated that the adsorption capacity to Cu2+ of P. putida 5-x cultured in sulfate-limiting medium reached maximum during the late stationary growth phase or early death phase, and reached minimum during the log growth phase. The mechanism of copper sequestering by this type of biomass was studied via transmission electron microscopy. A degradation of the peptidoglycan layer of the cell wall was observed in the acidic pretreatment, but no further degradation appeared after the adsorption-desorption cycle. Cu(II) accumulated mostly on the surface of the cell walls and was effectively desorbed by the acidic treatment during the desorption process.
研究了经酸性预处理的恶臭假单胞菌5-x的磁铁矿固定化细胞对废水中铜（II）（Cu[II]）离子的吸附和解吸。发现用0.6 N HCl预处理细胞可极大地提高生物质的吸附容量，最高可达85.6 mg/g，且对生物吸附剂预处理过程中恶臭假单胞菌5-x细胞的损失无显著影响。还研究了在不同生长阶段收获的恶臭假单胞菌5-x的磁铁矿固定化细胞对Cu2+的生物吸附容量。实验结果表明，在硫酸盐限制培养基中培养的恶臭假单胞菌5-x对Cu2+的吸附容量在稳定后期或死亡初期达到最大值，在对数生长期达到最小值。通过透射电子显微镜研究了这种生物质固定铜的机制。在酸性预处理中观察到细胞壁肽聚糖层的降解，但在吸附-解吸循环后未出现进一步降解。Cu（II）主要积累在细胞壁表面，在解吸过程中通过酸性处理可有效解吸。
