Trametes sp.SQ01和Chaetomium sp.R01混合培养对四种染料的脱色

利用本实验室新构建的白腐菌Trametes sp.SQ01和毛壳菌Chaetomium sp.R01混合培养体系,对刚果红、酸性红、橙黄G和溴酚蓝4种染料进行了脱色研究.结果表明,SQ01与R01混合培养所产生的锰过氧化物酶(MnP)酶活比菌株SQ01单独培养时提高了约5.5倍.菌株R01的接种量、接种时间对混合培养中...     

酿酒酵母吸附Pb(Ⅱ)的表面特性研究

为深入探讨酿酒酵母与Pb(II)的相互作用机理,本文利用表面显微分析技术（SEM-EDS、TEM-EDS、AFM）研究了酿酒酵母细胞吸附重金属离子Pb(II)前后的细胞表面特性变化。研究结果表明,酿酒酵母细胞与Pb(II)作用后,细胞表面除吸附Pb(II)外,同时产生大量更高浓度的含Pb(II)沉淀,导致Pb(II)从溶液中被去除。酵母与Pb(II)反应前,酵母细胞表面可检测到的主要元素包括C、O、N、P、S、K、Mg;酵母与Pb(II)作用后,细胞表面始终保持C、O、P吸收峰,而N、K、Mg、S吸收峰随反应条件不同而减弱、消失或增强。P作为细胞表面组分可能与Pb(II)结合。酵母与Pb(II)作用过程中,重金属离子促进酵母细胞释放细胞内含物。原子力显微镜（AFM）证实,云母片表面对酵母吸附Pb(II)后细胞的铺展变形作用明显增大。     

Biosorption of cesium（Ⅰ） from aqueous solution by a novel exopolymers secreted from Pseudomonas fluorescens C-2： Equilibrium and kinetic studies

The biosorption characteristics of Cs(I) ions from aqueous solution using exopolymers (PFC02) produced from Pseudomonas fluorescens C-2 were investigated as a function of pH, biosorbent dosage, contact time and initial concentration. pH played a major role in the adsorption process, and the optimum pH for the removal of Cs(I) was 8.0. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherm of the Cs(I) ions by PFC02. The Lagergren first-order, pseudo second-order kinetic and intraparticle diffusion models were used to test the kinetic data. Langmuir model and D-R model fitted the equilibrium data better than the Freundlich isotherm. The monolayer adsorption capacities of PFC02 as obtained from Langmuir isotherm at 25°C was found to be 32.63 mg/g. From the D-R isotherm model, the mean free energy was calculated as 26.73 kJ/mol, indicating that the biosorption of cesium was chemisorption. The biosorption process was rapid, and the kinetic rates were best fitted to the pseudo second-order model, which indicated the biosorption process operated through chemisorption mechanism. FT-IR analysis of PFC02 showed the possible functional groups responsible for cesium adsorption were hydroxyl, carboxyl, carbonyl and sulphonate groups. SEM analysis showed the porous structure of the material while EDX analysis confirmed the adsorption of Cs(I) on PFC02. Cesium adsorbed onto the PFC02 could be desorbed efficiently using 1 mol/L HNO3, and the enrichment factor was 50.0. Furthermore, PFC02 could be reused five times with only about 8.25% regeneration loss. The developed method was successfully utilized for the removal of Cs(I) ions from aqueous solution.     

改性磁性纳米颗粒固定内生菌Bacillus nealsonii吸附废水中Cd2+的特性研究

从重金属超累积植物龙葵体内提取内生菌Bacillus nealsonii,采用二氧化硅改性纳米Fe_3O_4颗粒与海藻酸钠将其包埋交联进行固定化,制得一种新型球状生物吸附剂,并应用于废水中Cd~(2+)的吸附处理.同时,通过正交实验研究了该球状生物吸附剂的最佳制备条件和吸附处理条件,并采用扫描电镜等表征手段与构建吸附动力学考察了其吸附特征.结果表明,球状生物吸附剂的最佳制备条件为:改性纳米Fe3O4颗粒质量分数为0.1%,海藻酸钠质量分数为8.0%,菌液接种量为0.4%,交联时间为2 h;其最佳吸附处理条件为p H=6、吸附时间12 h、吸附剂用量(干重)2.5 g·L-1,在Cd~(2+)初始浓度为50 mg·L-1时的吸附率可达96%以上.研究发现,球状生物吸附剂的内外部结构孔隙率较大,有利于促进Cd~(2+)的吸附.该吸附过程遵循准二级反应动力学,以化学吸附为主,符合Freundlich等温吸附模型,最大单分子吸附量可达13.02 mg·g-1.解吸实验结果表明,该吸附剂具有较好的可重复利用性.     

固定化铜绿假单胞菌吸附Cu~(2+)的特性

首次利用聚丙烯酰胺与壳聚糖形成的互融聚合物网络凝胶固定非活性的铜绿假单胞菌,并研究了这种新型的固定化微生物颗粒对Cu2+的吸附特性。该固定化微生物吸附剂表现出较好的吸附性能,对Cu2+的吸附很迅速,在40min内吸附基本达到平衡。对吸附动力学及平衡的研究表明,Cu2+在固定化微生物吸附剂上的吸附过程符合准二级动力学方程,吸附平衡符合Langmuir模型。     

青霉菌GX2对蒽醌染料的吸附作用

GX2生长菌体对 4种蒽醌染料均表现出优良的吸附性能 ,但由于染料分子的结构不同 ,吸附速率和吸附率也表现出一定的差异 .染料对菌体的生长具有一定的抑制作用 ,但即使在很高的染料浓度下 ,GX2生长菌体仍表现出很强的吸附性能 .对 250mg/L活性艳蓝KN-R的吸附率高达 100% ,对 400mg/LKN R的吸附率也可达91.4% .在 0～2%范围内 ,随着盐度 (NaCl)的增加 ,菌体干重增加 ;颗粒状菌团的直径却随之减小 ,比表面积增大 ,对GX2生长菌体的染料吸附表现出较为明显的促进作用 .碳源浓度通过影响菌体的生长而影响染料吸附 ,当培养基中的葡萄糖浓度大于 2.5g/L时 ,即可使浓度为 120mg/L的活性艳蓝KN R溶液完全脱色 .生长菌体具有比静止活体和死体更好的吸附性能 .     

重金属离子的生物吸附容量与离子性质之间的关系

利用金属离子毒性评价和预测领域中的QSAR方法,探讨了重金属离子性质对生物吸附容量的影响．选用啤酒工业废弃的酿酒酵母为生物吸附剂,进行了10种金属离子Ag^＋,Cs^＋,Zn^＋,Pb^2＋,Ni^2＋,Cu^2＋,CO^2＋,Sr^2＋,Cd^2＋,Cr^3＋的生物吸附实验．选用22种参数来表征金属离子的物理化学性质,建立了金属的离子特性与生物吸附容量之间的关系．利用Langmuir方程计算得到酵母吸附金属离子的理论最大吸附量qmax,由大到小排序为Pb^2＋〉Ag^＋〉Cr^3＋〉Cu^2＋〉Zn^2＋〉Cd^2＋〉Co^2＋〉Sr^2＋〉Ni^2＋〉Cs^＋．离子性质与吸附量之间的线性拟合分析结果表明,共价指数Xm^2r与qmax具有良好的线性关系,共价指数越高,离子吸附量越大,金属离子与吸附剂表面官能团共价结合所占比重越大,键结合越牢固．对金属离子进行分类（按价态或离子的软硬性质）可以改善拟合效果．极化力Z^2／r、水解常数｜lgKOH｜、电离势,尸等多种物化性质与不含软离子的离子之间的理论最大吸附量也表现出良好的线性关系．     

Screening of wood rotting fungi potentially useful for the degradation of organic pollutants

Many papers have shown that white rot fungi can degrade aromatic pollutants under laboratory conditions, but few report field scale trials. Here we report the first steps in the development of a remediation system for Greek conditions. A review of the available organochlorine compound pollution information in Greece is presented. White rot fungi isolated from sites in Greece have been screened for growth rate and ligninolytic activity, using decolourisation of the dye Poly R-478 as an indicator of enzyme activity. Use of white rot fungi under field conditions in Greece will require bioaugmentation to be effective at high temperatures and low water activity for much of the year. The most potent strains have been selected under a range of conditions and have been challenged with priority pollutants to determine their degradative ability under laboratory conditions and subsequently ex situ in soil.     

Remediation of Persistent Organic Pollutants Using a Novel Two-Phase Soil Washing Biosorption Process

A two-phase soil washing biosorption process was developed for the remediation of p,p-DDT-contaminated soil. The process involved desorption of contaminants from soil using dilute primary alcohols (40% 1-propanol) followed by contaminant removal from cosolvent solutions using fungal biosorption. Bench scale remediation studies were preformed to simulate ex situ (recycling experiment) or in situ (soil column study) treatment strategies. Both systems were effective at cleaning the soil to below Australian regulatory p,p-DDT levels. After 50–80 hours of soil washing, over 93% of p,p-DDT was removed from the soil(990 mg kg^-1 to <65 mg kg^-1) using either of these methods.p,p-DDT was removed from the cosolvent phase by sorption onto the fungal biomass. This resulted in only low levels of p,p-DDT remaining in the cosolvent solution(<1.5 mg l^-1). The application of both treatment strategies resulted in the rapid clean up of p,p-DDT-contaminated soil and the potential to recycle cosolvent solutions. The ability to recycle cosolvent solutions provides a mechanism for cost reductions of the remediation strategy.     

Biosorption of cadmium(Ⅱ) and lead(Ⅱ) ions from aqueous solutions onto dried activated sludge

The removal of heavy-metal ions from aqueous solutions by using dried activated sludge has been investigated in batch systems. Effect of solution pH, initial metal ion concentration, and temperature were determined. The results of the kinetic studies showed that the uptake processes of the two metal ions(Cd(Ⅱ) and Pb(Ⅱ)) followed the pseudo-second-order rate expression. The equilibrium data fitted very well to both the Langmuir and Freundlich adsorption models. The FT-IR analysis showed that the main mechanism of Cd(Ⅱ) and Pb(Ⅱ) biosorption onto dried activated sludge was their binding with amide I group.