融合酵母对重金属Cr的富集机理

研究了1株高效融合酵母对Cr的富集机理及其微观结构变化.研究结果表明,融合酵母对Cr6+的还原、吸附过程伴随着溶液H+离子的消耗.菌体表面的络合基团主要有氨基、羟基、磷酸基等,其中磷酸基团对吸附的影响最大,该基团屏蔽后总Cr去除率及Cr6+还原率分别降低了70%和46%;吸附过程趋向于将表面络合的Cr运输至细胞内并和细胞内物质形成更稳定的结合态,该过程可在吸附90min内达到平衡;Cr在细胞表面的吸附及还原作用会改变细胞微观结构,使细胞通透性增强.

Mechanism of Chromium Accumulation by Fused Yeast

The mechanism of chromium accumulation and microstructure transformation of the fused yeast were studied in this paper. The result showed that the process of Cr6+ reduction and adsorption was accompanied by the H+ consumption. The main adsorptive groups on the strain surface included amino, hydroxyl, phosphate group and amide, among which phosphate group played vital role in the chromium accumulation. The removal rate of chromium and reduction rate of hexavalent chromium declined 70% and 46%, respectively, when phosphate group was masked. During the adsorption process the chromium ions complexed on the surface of fused yeast was transported into the cell wall and combined with inclusion to form steady species and this took 90 min to reach the equilibrium. The biosorption and reduction of Cr on the cell surface would alter microstructure of cell surface, reduce cell membrane potential and increase cell membrane permeability.