紫外诱变黄孢原毛平革菌染料脱色研究

对黄孢原毛平革菌孢子悬浮液进行了紫外诱变，并将筛选出的优势菌ZWYB1与未经诱变的菌作对比实验，结果表明：诱变筛选得到的ZWYB1不仅可缩短对染料的脱色时间，提高对杂环类染料蕃红花红及高浓度染料400mg／L的孔雀石绿的脱色效果，而且诱变后的菌种具有一定的脱色能力稳定性。     

紫外诱变黄孢原毛平革菌染料脱色研究

对黄孢原毛平革菌孢子悬浮液进行了紫外诱变,并将筛选出的优势菌ZWYB1与未经诱变的菌作对比实验,结果表明:诱变筛选得到的ZWYB1不仅可缩短对染料的脱色时间,提高对杂环类染料蕃红花红及高浓度染料400 mg/L的孔雀石绿的脱色效果,而且诱变后的菌种具有一定的脱色能力稳定性.     

黄孢原毛平革菌降解磺胺甲噁唑的影响因素

采用摇瓶实验考察固定化培养黄孢原毛平革菌(Phanerochaete chrysosporium)对磺胺甲噁唑(SMX)的降解效果并对抗生素降解条件进行优化。结果表明,黄孢原毛平革菌在固定化培养后对SMX的降解能力有所提高,10 d后培养液中抗生素去除率达到了100%,而游离培养液中去除率为74%。固定化黄孢原毛平革菌降解磺胺甲噁唑的较优碳源和氮源分别是葡萄糖和酒石酸铵,初始pH范围在3.0~5.0之间、培养温度为30~40℃时较适宜。黄孢原毛平革菌对磺胺甲噁唑的降解受碳源种类影响较大,而在限氮条件下氮源的差异对其影响较小。     

Cellobiose dehydrogenase-dependent biodegradation of polyacrylate polymers by Phanerochaete chrysosporium

When Phanerochaete chrysosporium was cultured using conditions which promote the expression of cellobiose dehydrogenase (CDH), but not the ligninolytic peroxidases, the fungus effectively solubilized and mineralized an insoluble, crosslinked polyacrylate and an insoluble polyacrylate/polyacrylamide copolymer. Addition of iron to the cultures increased CDH activity in the cultures and the rate and extent of solubilization and mineralization of both polymers. Solubilization of both polymers was observed when incubated with purified CDH, ferric iron and hydrogen peroxide.     

Characterization of polycyclic aromatic hydrocarbons from the diesel engine by adding light cycle oil to premium diesel fuel

Diesel fuels governed by U.S. regulations are based on the index of the total aromatic contents. Three diesel fuels, containing various fractions of light cycle oil (LCO) and various sulfur, total polyaromatic, and total aromatic contents, were used in a heavy-duty diesel engine (HDDE) under transient cycle test to assess the feasibility of using current indices in managing the emissions of polycyclic aromatic hydrocarbons (PAHs) from HDDE. The mean sulfur content in LCO is 20.8 times as much as that of premium diesel fuel (PDF). The mean total polyaromatic content in LCO is 28.7 times as much as that of PDF, and the mean total aromatic content in LCO is 2.53 times as much as that of PDF. The total polyaromatic hydrocarbon emission factors in the exhaust from the diesel engine, as determined using PDF L3.5 (3.5% LCO and 96.5% PDF), L7.5 (7.5% LCO and 92.5% PDF), and L15 (15% LCO and 85% PDF) were 14.3, 25.8, 44, and 101 mg L(-1), respectively. The total benzo(a)pyrene equivalent (BaPeq) emission factors in the exhaust from PDF, L3.5, L7.5, and L15 were 0.0402, 0.121, 0.219, and 0.548 mg L(-1), respectively. Results indicated that using L3.5 instead of PDF will result in an 80.4% and a 201% increase of emission for total PAHs and total BaPeq, respectively. The relationships between the total polyaromatic hydrocarbon emission factor and the two emission control indices, including fuel polyaromatic content and fuel aromatic content, suggest that both indices could be used feasibly to regulate total PAH emissions. These results strongly suggest that LCO used in the traveling diesel vehicles significantly influences PAH emissions.     

Phanerochaete chrysosporium吸附载体的选择及染料降解研究

研究了游离细胞与载体吸附培养、不同载体材料对Phanerochaete chrysosporium进行连续染料脱色及产酶能力的影响。结果表明,P.chrysosporium可在载体上良好生长,甚至生长到载体内部。木屑、玉米芯、花生壳3种载体材料中,以木屑载体吸附培养物的持续脱色和产酶效果最佳,该培养物经三轮连续脱色后对染料RB5仍能达到最高95%的脱色率,并产生596 U/L锰依赖过氧化物酶（MnP）和1 326 U/L木质素过氧化物酶（LiP）,对染料的持续脱色和产酶能力明显优于游离细胞培养物。     

载体吸附培养黄孢原毛平革菌(Phanerochaete chrysosporium)和云芝(Trametes versicolor)对染料的脱色

比较研究了不同载体吸附培养的黄孢原毛平革菌(Phanerochaete chrysosporium)和云芝(Trametes versicolor)对染料连续脱色的效果。结果表明:(1)白腐真菌黄孢原毛平革菌和云芝分别在含有球形的木屑、玉米芯和花生壳载体的液体环境中振荡培养,菌体以膜状或团状形式大量附着生长在载体表面。(2)连续4轮脱色过程中,不论黄孢原毛平革菌还是云芝,都是木屑为载体的培养液的持续脱色和产酶能力最好,宜选择木屑为载体。其中,木屑为载体的黄孢原毛平革菌培养液经过2轮连续12d脱色后对活性黑RB5的最高脱色率仍能达到97%,在第3轮脱色中对活性红M-3BE的最终脱色率接近96%,并且能产生最高611U/L的锰依赖过氧化物酶(MnP)和1 477U/L的木质素过氧化物酶(LiP)。(3)在实际应用中应该将木屑为载体的黄孢原毛平革菌和云芝培养液都投加到含染料废水处理系统中,强化生物处理效果。     

三株白腐菌产锰过氧化物酶活性及其对多环芳烃的降解

比较研究了β-环糊精(β-CD)对3株黄孢原毛平革菌(Phanerochaete chrysosporium)CGMCC5.776、GIM3.383和GIM3.393产锰过氧化物酶(MnP)和降解多环芳烃(PAHs)的影响.结果表明:3株菌都能分泌出高活性的MnP,β-CD能显著提高MnP的活性.加入2.0 g/Lβ-CD的体系培养到第12天时.酶活性最高达到2 912.5 U/L;而且β-CD能显著提高PAHs的降解率,两者之间存在较好的相关性.加入1.0 g/L β-CD的体系对比不加β-CD的体系,PAHs的降解率提高了1～2倍.PAHs的降解同时受到MnP活性、PAHs表观溶解度和分子结构稳定性等因素的影响.     

Cellular and molecular damage of Phanerochaete chrysosporium by the oxidation hair dyes

Introduction

The toxic effect of the oxidation hair dyes on Phanerochaete chrysosporium was investigated by exposure of this fungus in a nitrogen-limited culture medium to various concentrations of the oxidation hair dyes.

Results

The results showed that both the size and the dry weight of the mycelial pellets of P. chrysosporium could be reduced when the concentration of the oxidation hair dyes was higher than 300?mg/L. By using the AFLP analysis and the UPGMA dendrogram, the DNA damage of P. chrysosporium by the oxidation hair dyes was also detected. Comparing with that in the control, the percent polymorphism under different concentrations of the oxidation hair dyes increased. In the meantime, the DNA similarity was decreased, which meant that the DNA damage was aggravated with an increase in the concentrations of the oxidation hair dyes.

Conclusion

Thus, as an environmental pollutant, the oxidation hair dyes have a toxic effect on P. chrysosporium at both cellular and molecular levels.     

Assessment of natural attenuation of volatile aromatic hydrocarbons in agricultural soil contaminated with diesel fuel

A diesel fuel spill was simulated on a 12-m(2) plot of agricultural land, at a concentration of 1 Lm(-2) of soil. The natural attenuation of Volatile Aromatic Hydrocarbons (VAHs) was monitored at different soil depths over a period of 50 days. The natural attenuation of VAHs in the surface layer would be attributed to two processes, namely: volatilisation (mainly linked to the boiling point of each VAH, with t(1/2) from 2 to 71 min for benzene and p-isopropyltoluene, respectively); and dissipation (related to the boiling point as well as the analyte-soil matrix interaction, with t(1/2) from 2 to 169 h for benzene and p-isopropyltoluene, respectively). As expected, in the deeper layers, dissipation prevails over volatilisation. 50 days after the spill, only two VAHs were detected in the surface layer, at concentrations of 5-20 ngg(-1), which had disappeared after 80 days of the spill.     

Characteristics in oxidative degradation by ozone for saturated hydrocarbons in soil contaminated with diesel fuel

Although alkanes are relatively less reactive to chemical oxidation compared to alkenes, the chemical oxidation of alkanes has not been adequately explored in the context of environmental remediation efforts. Laboratory-scale column experiments were therefore conducted with soil artificially contaminated by diesel fuel as a surrogate for alkanes of environmental relevance. Particular attention was paid to saturated hydrocarbons refractory to volatilization. Reaction conditions involve 1485mgkg(-1) of the initial concentration of diesel range organics (DRO) and a constant ozone concentration of 119+/-6mgl(-1) at the flow rate of 50mlmin(-1). The observed removal of DRO reached 94% over 14h of continuous ozone injection. Ozone oxidation demonstrated effective removal of non-volatile DRO in the range of C(12)-C(24). Each alkane compound displayed comparable degradation kinetics, suggesting virtually no selectivity of ozone reactions with alkanes in soil. A pseudo-first order kinetic model closely simulated the removal kinetics, yielding a reaction rate constant of 0.213 (+/-0.021)h(-1) and a half-life of 3.3 (+/-0.3)h under the experimental conditions used in this study. An estimate of ozone demand was 32mg of O(3) (mgDRO)(-1).     

Influence of diesel fuel on seed germination

The use of plant-based systems to remediate contaminated soils has become an area of intense scientific study in recent years and it is apparent that plants which grow well in contaminated soils need to be identified and screened for use in phytoremediation technologies. This study investigated the effect of diesel fuel on germination of selected plant species. Germination response varied greatly with plant species and was species specific, as members of the same plant family showed differential sensitivity to diesel fuel contamination. Differences were also seen within plant subspecies. At relatively low levels of diesel fuel contamination, delayed seed emergence and reduced percentage germination was observed for the majority of plant species investigated. Results suggest the volatile fraction of diesel fuel played an influential role in delaying seed emergence and reducing percentage germination. In addition, the remaining diesel fuel in the soil added to this inhibitory effect on germination by physically impeding water and oxygen transfer between the seed and the surrounding soil environment, thus hindering the germination response.     

Tripolyphosphate-assisted electro-Fenton process for coking wastewater treatment at neutral pH

Environmental Science and Pollution Research - The first application of a novel electro-Fenton (EF) for coking wastewater (CW) treatment at the original pH (6.80) by using tripolyphosphate (TPP)...     

黄孢原毛平革菌降解比布列希猩红的水处理反应器的设计和比较

以染料比布列希猩红为降解对象,采用细胞固定化技术,建立6种黄孢原毛平革菌的水处理反应器工作体系。研究表明,海藻酸钙小球-生物流化床、不锈钢网片反应器、以海绵和泡沫为载体的池形反应器（反应器Ⅰ和Ⅱ）及以裹夹生物海绵的钢丝网为载体的池形反应器（反应器Ⅲ和Ⅳ）等不同类型的反应器均具有较好的处理效果;15—16d内,染料脱色降解率可达95％左右。相比较而言,反应器Ⅳ具有操作简单、反应启动快、处理水量大和节能低耗等优点。     

Bioaccumulation of aluminium in the freshwater snail Lymnaea stagnalis at neutral pH

This study examined the accumulation of aluminium (Al) by the freshwater snail Lymnaea stagnalis at neutral pH, when most Al would be predicted to be in an insoluble form (Al(OH)(3)). Snails were exposed to a range of Al concentrations (38-285 microg l(-1)) for 30 days, followed by 20 days in clean water. Aluminium was measured using atomic absorption spectroscopy. Significant accumulation of Al occurred in the whole soft tissues, gut, digestive gland and kidney at the latest by day 10. High concentration factors were observed, ranging from 4.5 x 10(3) in the whole soft tissues to 6.3 x 10(4) in the kidney, corresponding to actual concentrations of 800 to 7500 microg g(-1), respectively. Proportionality between environmental (water) and tissue concentrations of Al was observed in the gut but not in the other tissues. Following transfer to clean water, rapid loss of Al from the whole soft tissues and gut was seen over the first 10 days. Loss of Al from the digestive gland was much less as a proportion of the total, with approximately 90% of the Al remaining in the tissue. In contrast, significant loss of Al from the kidney occurred between days 20 and 30, even in the continued presence of Al; little further loss occurred following transfer to clean water. Aluminium is clearly available to the snail at neutral pH, the most likely route of entry being the gut. This could facilitate entry of the metal into the food chain. The possible roles of the digestive gland and kidney in the handling of Al are discussed.     

Effect of humic substances on the Fenton treatment of wastewater at acidic and neutral pH

This paper describes results of treatability studies of the effect of humic substances (humate, HS, at the concentration 500-5000 mg l-1) on the Fenton (Fe2+/H2O2) treatment of industrial wastewater at pH 3.5 and 7.0. Without humate, the removal of all contaminants was significantly higher at pH 3.5 than at pH 7. At pH 7.0, the removal of all compounds in the presence of HS (3000 mg l-1) was comparable to that at pH 3.5 without HS. At pH 3.5, humate had no effect on the removal of arsenic, thiocyanate and cyanide, but the removal of all organic compounds (phenol, 2,4-dimethylphenol, benzene, toluene, o-xylene, m- & p-xylene and dichloromethane) was significantly inhibited. Mechanisms of the processes are discussed. It is suggested that, in the presence of HS, acidification of the treated wastewater may not only be unnecessary but it can even hinder the degradation of organic pollutants.     

Study of the degradation of dyes by MnP of Phanerochaete chrysosporium produced in a fixed-bed bioreactor

The production of ligninolytic enzymes by the fungus Phanerochaete chrysosporium in a fixed-bed tubular bioreactor, filled with cubes of nylon sponge, operating in semi-solid-state conditions, was studied. Maximum individual manganese-dependent peroxidase (MnP) and lignin peroxidase (LiP) activities of 1293 and 225 U/l were detected.The in vitro decolourisation of two structurally different dyes (Poly R-478, crystal violet) by the extracellular liquid obtained in the above-mentioned bioreactor was monitored in order to determine its degrading capability. The concentration of some compounds (sodium malonate, manganese sulphate) from the reaction mixture was optimised in order to maximise the decolourisation levels. A percentage of Poly R-478 decolourisation of 24% after 15 min of dye incubation was achieved.On the other hand, a methodology for a long treatment of these dyes based on the continuous addition of MnP enzyme and H(2)O(2) was developed. Moreover, this enzymatic treatment was compared with a photochemical decolourisation process. The former allowed to maintain the degradation rate almost constant for a long time, resulting in a decolourisation percentage of 70% and 30% for crystal violet and Poly R-478, respectively, after 2 h of treatment. As for the latter, it was not able to degrade Poly R-478, whereas crystal violet reached a degradation of 40% in 2 h.     

Benzo[a]pyrene removal from soil by Phanerochaete chrysosporium grown on sugarcane bagasse and pine sawdust

The capacity of Phanerochaete chrysosporium grown on soil with added sugarcane baggase (BP) and pine sawdust (PS) to remove benzo(a)pyrene (BaP) was studied. A half factorial two-level experiment 2(4-1) was designed to determine the effect of: type of lignocellulosic material (BP and PS) for fungus growth, age of fungus (5 and 10d), amount of lignocellulosic material (10% and 15% w/w) and soil moisture content (water holding capacity of 45% and 56% w/w). Inoculum obtained at different ages showed that the capacity of P. chrysosporium to remove BaP depends on the lignocellulosic used and on inoculum age. Abiotic BaP removal was affected significantly (p<0.05) by inoculum age, type of lignocellulosic added and soil moisture content. The removal of BaP by lignocellulosic material was more effective by young inocula (71.97 mg BaP kg(-1) dry soil), with high percentage of added lignocellulosic (71.57 mg BaP kg(-1) dry soil) and at low soil moisture content (73.07 mg BaP kg(-1) dry soil). When fungus was grown on BP, maximum BaP removal rate was obtained at 5d of incubation (10.85 mg BaP d(-1)l(-1) and 50.12 mg BaP kg(-1) dry soil), while in PS maximum BaP removal was obtained at 10d of incubation (12.06 mg BaP d(-1)l(-1) and 39.94 mg BaP kg(-1) dry soil).     

Mycelial growth and solid-state fermentation of lignocellulosic waste by white-rot fungus Phanerochaete chrysosporium under lead stress

Lignocellulosic biomass is an abundant renewable resource difficult to degrade. Its bioconversion plays important roles in carbon cycles in nature, which may be influenced by heavy metals in environment. Mycelial growth and the degradation of lignocellulosic waste by lignin-degrading fungus Phanerochaete chrysosporium under lead stress were studied. It was shown that P. chrysosporium could grow in liquid media with 400 mg L?1 Pb(II), and mycelial dry weight was reduced by 54% compared to the control. Yellow mycelia in irregular short-strip shape formed in Pb-containing media, whereas the control showed ivory-white regular mycelial pellets. Two possible responses to Pb stress were: dense hyphae, and secretion from mycelia to resist Pb. During solid-state fermentation of straw, fungal colonization capability under Pb stress was positively correlated with the removal efficiency of soluble-exchangeable Pb when its content was higher than 8.2 mg kg?1 dry mass. Carboxymethyl cellulase activity and cellulose degradation were inhibited at different Pb concentrations, whereas low Pb concentrations increased xylanase and ligninolytic enzyme activities and the hemicellulose and lignin degradation. Cluster analyses indicated that Pb had similar effects on the different microbial indexes related to lignin and hemicellulose degradation. The present findings will advance the understandings of lignocellulose degradation by fungi under Pb pollution, which could provide useful references for developing metal-polluted waste biotreatment technology.     

燃油催化微粒捕集器在柴油机排气后处理中的应用研究

分析探讨了柴油机排气颗粒物的组成及危害,介绍了一种燃油催化微粒捕集器的结构及原理,结合发动机台架试验数据分析了该微粒捕集器对柴油机排气颗粒物的改善效果,同时研究了该微粒捕集器的强制再生过程以及对柴油机动力性和燃油经济性的影响.试验结果表明,该微粒捕集器具有较大的应用前景.