草酸青霉Penicillium oxalicum菌体吸附活性染料的性能及微观过程

研究了草酸青霉(Penicillium oxalicum)在模拟染料废水中以边生长边吸附的方式对活性翠蓝KN-G, M-GB, K-GL，活性黑K-BR、活性艳蓝M-BR、活性红紫K-3R和活性深蓝K-R 7种水溶性活性染料的脱色性能及吸附过程. 结果显示，生长菌体对7种活性染料具有良好的脱色性能，染料初始浓度为200 mg/L时，平均脱色率可达93.0%；染料初始浓度为400 mg/L时，活性翠蓝KN-G和M-GB的脱色率仍达到了99.7%和99.9%. 上清液的紫外光谱图及染料分子中铜离子浓度的检测结果表明，染料通过吸附方式从废水中去除. 通过SEM, TEM观察发现，生长菌体在吸附过程中，菌丝发生肿胀膨大，细胞壁发生结构重组，厚度增加10~15倍. 细胞壁的结构变化是生长菌体吸附染料的重要机制，为染料吸附提供位点和进入细胞内部的通道.

Decolorization Ability and Microcosmic Biosorption Process of Reactive Dyes with Fungus Penicillium oxalicum

The decolorization ability and adsorption process of seven water-soluble reactive dyes, namely Reactive Turquoise Blue KN-G, Reactive Black K-BR, Reactive Turquoise M-GB, Reactive Brilliant Blue M-BR, Reactive Violet K-3R, Reactive Dark Blue K-R and Reactive Turquoise Blue K-GL, with Penicillium oxalicum were studied when the strain was growing in the simulative dye wastewater. It was found from adsorption experiments that the growing Penicillium oxalicum possessed excellent adsorption ability to the reactive dyes. At lower initial dye concentration (200 mg/L), the average decolorization rate of seven dyes reached 93.0%, at higher initial dye concentration (400 mg/L), the decolorization rates of Reactive Turquoise Blue KN-G and Reactive Turquoise M-GB were 99.7% and 99.9% respectively. Spectrophotometric analysis of supernatants and tracing of Cu2+ (which is contained in the dye molecules) concentration in the supernatants indicated that the decolorization of dyes by Penicillium oxalicum biomass involved an adsorption process. Scanning electron microscope (SEM) and transmission electron microscope (TEM) images illustrated that the hyphae of the fungus swelled, the structure of the cell wall was reconstituted and the thickness of the cell wall increased about 10~15 folds. The cell wall played an important role in dye biosorption by growing fungus. It not only offered the major biosorption sites for the dyes, but also provided routeway for the dye molecules to enter the cells.