Decolourization of textile dyes by the white‐rot fungi Phanerochaete chrysosporium and Pleurotus ostreatus

BACKGROUND: The ability of the fungi Pleurotus ostreatus and Phanerochaete chrysosporium to decolourize and detoxify 11 (mono‐, dis‐, poly‐ azo, and anthraquinonic type) dyes, widely used across the textile and leather industries, was tested. RESULTS: Different substrate specificities were revealed between P. ostreatus and P. chrysosporium in decolourization experiments. The latter fungus provided almost complete decolourization of the tested azo dyes up to 600 ppm and dis‐azo dyes up to 1000 ppm, and 80% decolourization of the tris‐azo dye DBU1L38 at 1000 ppm, after 6 days. P. ostreatus provided almost total decolourization of the anthraquinone type dye ABU62 (1000 ppm) after just 1 day. P. ostreatus also showed the ability to decolourize the tested dis‐azo and tris‐azo dyes, giving the best performances against the dis‐azo DBU1U1 (600 ppm) dye, which was 100% decolourized after 6 days. Laccases proved to be the main enzymatic activities acting in P. ostreatus decolourization. CONCLUSION: The potential of the fungi P. ostreatus and P. chrysosporium as efficient bio‐systems for decolourization and detoxification of several toxic industrial dyes was demonstrated. The role of laccases in the decolourization of dis‐azo dyes by P. ostreatus was demonstrated for the first time. Copyright © 2008 Society of Chemical Industry     

黄孢原毛平革菌产酶的简化结构动力学模型

In order to understand the behavior of ligninolytic enzyme production by white rot fungi Phanerochaete chrysosporium, study on time courses and a mathematical model for the production of lignin peroxidase (LiP) and manganese peroxidase (MnP) of the fungi was undertaken. Based on the Monod-Jacob operon model, the ligninolytic enzyme would be synthesized in the absence of a related repressor. The repressor is assumed to be active in the presence of ammonia nitrogen, and as combined as co-repressor, it causes the inhibition of enzyme synthesis. The model can explain the mechanism of extracellular ligninolytic enzyme production by white rot fungi. The results,as predicted by the model, correspond closely to those observed in experimental studies. In addition, some light is also shed on unmeasured variables, such as the concentrations of repressor and mRNA that are related to the enzyme synthesis.     

碳/氮源调控下白腐真菌处理复配染料废水

利用自行分离、紫外诱变的一株白腐真菌12^#诱1。研究了碳／氮源调控下白腐真菌生物膜反应器处理复配染料废水的出水特性（色度、pH值、氨氮和总氮浓度）变化情况，初步分析了这些指标变化的内在关系。研究结果表明：在较低的碳源浓度为极限氮条件下该反应器对复配染料废水具有很好的脱色降解效果：氮源浓度及类型对处理出水特性有重要影响。     

Decolourisation of Orange II by a Wood-Rotting Fungus

The decolourisation of Orange II by a wood-rotting fungus has been studied. It was found that Fungus F29 could effectively decolourise Orange II especially when grown as pelleted mycelia under agitated conditions. Many factors affecting the decolourisation process in nitrogen-limited media (NLM) were studied, including: concentration of glucose, NH₄⁺, Mn(II) and veratryl alcohol; initial pH; amount of mycelium; mycelial age; Orange II concentration; temperature. Results showed that the media containing Orange II at 1000 mg dm⁻³ (or higher) could be decolourised by 98% of the initial colour (A_{480 nm}) in 2 days, in most conditions tested, and that the mycelia could be repeatedly reused. © 1997 SCI.     

Removal of polycyclic aromatic hydrocarbons from soil using surfactant and the white rot fungus Phanerochaete chrysosporium

The bioremediation of soil contaminated with polycyclic aromatic hydrocarbons (PAH) is often limited by a low bioavailability of the contaminants. Non‐ionic surfactants, such as Tween 80, when above their critical micelle concentration (CMC), can efficiently enhance the bioavailability of PAHs in contaminated soil by increasing solubility and dissolution rates. However, disposing of this micelle‐contaminated spent washwater can be a major problem. The aim of this study was to combine surfactant soil washing techniques using Tween 80 with the versatile lignin‐degrading system of the white rot fungus, Phanerochaete chrysosporium, to bioremediate PAH‐contaminated soil. Approximately 85% (w/w) of a total of nine PAHs in an aged (1 month) contaminated soil (total PAH concentration = 403.61 µg g⁻¹) could be solubilized in a 2.5% (w/v) Tween 80 solution at a soil/water ratio of 1:10. The washwater was then catabolized by a 3‐day‐old culture of P chrysosporium under a stationary condition. The disappearance of most PAHs tested (molecular weight ≥ 178) correlated well with their ionization potentials and 66.4% (w/w) of the total PAHs in washwater with 2.5% (w/v) Tween 80 was catabolized after 11 days of culture. The catabolism was enhanced to 86% (w/w) using a lower concentration of 0.5% (w/v) Tween 80. The initial oxidation rate of total PAHs based on the first 4 days of culture remained almost constant at approximately 1.88 µg cm⁻³day⁻¹ when the Tween 80 concentration in washwater was increased from 0.5% to 2.5% (w/v). The combination of soil washing and white rot fungus catabolization of PAH using 2.5% (w/v) Tween 80 eliminated the total PAH concentration in the contaminated soil by 56.4% (w/w) after 11 days. The results suggest that PAH‐contaminated soil may be cleansed by using a combination of surfactant soil washing and white rot fungus catabolism. © 2000 Society of Chemical Industry     

Effect of non‐ionic surfactants on elimination of polycyclic aromatic hydrocarbons (PAHs) in soil‐slurry by Phanerochaete chrysosporium

Surfactants can enhance bioremediation of soil contaminated with polycyclic aromatic hydrocarbons (PAHs) by increasing their bioavailability. The objective of this study was to evaluate the effect of non‐ionic polyoxyethylene (POE) surfactants on the elimination of nine PAHs in contaminated soil by the white rot fungus Phanerochaete chrysosporium. PAHs in both liquid and solid phases were extracted and then assayed using GC–MS. Fungal biomass concentration and the activity of extracellular ligninolytic enzymes were used to determine the toxicity of POE surfactants. Results indicated that 0.5% (w/v) of surfactant Tween 80 was not toxic to fungal growth and had little impact on extracellular ligninolytic enzyme synthesis. About 80% of low ring PAHs (ie acenaphthene and fluorene) could be efficiently catabolized by P chrysosporium without surfactants, while catabolism of others (ie phenanthrene, fluoranthene, pyrene, chrysene, benzo(a)pyrene, dibenz(ah)anthracene and benzo(ghi)perylene) was less than 30% over a 8‐day culture period. Elimination of four‐to six‐ring PAHs in contaminated soil was enhanced in P chrysosporium cultures with 0.4% (w/v) Tween 80 by 15–33% compared with those in cultures without Tween 80, while no obvious effect was observed in the elimination of three‐ring PAHs over the culture period. Investigations on PAH concentrations in aqueous phase during the culture period showed that Tween 80 increased PAH aqueous concentrations and the PAH oxidation rate in aqueous was rapid. Enhancement of soil PAH elimination in the presence of Tween 80 was due to the increased PAH bioavailability. © 2001 Society of Chemical Industry     

Comparing Different Designs and Scales of Bubble Columns for Their Effectiveness in Treating Kraft Pulp Mill Effluents

The experimental results obtained in three different types of ozone contactors were analyzed to study the effects of the ozone contactor design, configuration, operating conditions, and scale-up on the: (1) ozonation process induced reduction efficiencies of color, AOX, COD, and TOC from biologically treated Kraft pulp mill effluents; (2) the increase in biodegradability of this type of wastewater; and (3) the dynamics of the ozone gas absorption process. The three types of ozone contactors included: (1) an extra-coarse-bubble diffuser ozone contactor; (2) an impinging-jet ozone contactor; and (3) a fine-bubble diffuser ozone contactor. Similar treatment levels were achieved in those ozone contactors although the impinging-jet bubble column was more effective in treating Kraft pulp mill effluents due to its smaller reactor volume and lower off-gas ozone concentrations. Consequently, the operating costs of an ozonation process and ozone off-gas destruction facilities will be greatly reduced when using the impinging-jet bubble column design for treating Kraft pulp mill effluents.     

Screening of white rot fungi for the treatment of olive mill waste-waters

Several white rot fungi were evaluated for their ability to decolorize olive mill waste-waters (OMW). Among these, Phanerochaete chrysosporium showed the highest potential for the biological depollution of OMW. Approximately 65% of the color and 73% of the chemical oxygen demand (COD) were removed by P. chrysosporium strain HD. Phlebia radiata, Dichomitus squalens, Polyporus frondosus and Coriolus versicolor could also decolorize the OMW but to a lesser extent. The different abilities of these white rot fungi to decolorize OMW correlated with their rates of depolymerization of high molecular weight aromatics and the degradation of the low molecular weight aromatic compounds. Fourteen strains of P. chrysosporium were compared on the basis of their lignin peroxidase (LiP) production, OMW decolorization and residual material dry weight. High lignin peroxidase producer strains, such as strains HD and BKM-F-1767, showed the highest rates of OMW decolorization, P. chrysosporium strains 79–36 and FP 104297 (low LiP producer strains) did not exhibit any decolorization activity.     

Removal of Ethylenediaminetetraacetic acid (EDTA) from Pulp Mill Effluents by Ozonation

Ozone application was investigated for its effectiveness in the removal of ethylenediaminetetraacetic acid (EDTA) from bleaching effluent. The objectives were to compare the efficiency of ozone reaction on Na-EDTA solution with pure Fe³⁺-EDTA complex and EDTA complexes in bleaching effluent, and to test if changing pH and addition of hydrogen peroxide (H₂O₂) increases the removal of EDTA. Small ozone doses destroyed high proportions of Na-EDTA. This effect was diminished when EDTA formed complexes with other metal ions. It was shown that EDTA present in bleaching effluent was more easily oxidizable than in pure Fe³⁺-EDTA solution. Variation of initial pH value had no significant influence on the removal of Na-EDTA. Addition of hydrogen peroxide did not increase degradation of EDTA in bleaching effluent.     

白腐真菌处理难生物降解的有机废水研究

作者概述了白腐真菌的特性和降解机理,同时利用白腐真菌生化降解两种生物难降解的有机废水。实验结果表明,白腐真菌对生物难降解的ＴＮＴ炸药废水和分散染料废水有着良好的降解性能,显示广阔的应用前景。     

白腐真菌对染料的脱色降解及应用前景

通过对国内外文献的追踪,并结合实际研究结果,综合论述了白腐真菌对染料脱色降解的基本原 理、主要规律,以及各种染料和染料工业废水的生物降解性:总结展望了利用白腐真菌技术在染料工业废 水治理的实践中,所需解决的问题和应用的前景.     

白腐真菌处理硝基苯化合物的机理初探

以白腐真菌锰过氧化物酶(MnP)为主导酶处理硝基苯化合物,并研究了其独特的降解机理.通过测定不同浓度硝基苯溶液的吸光度,确定了硝基苯溶液标准曲线.用莫诺特(Monod)方程对实验数据进行模拟,应用Lineweaver-Burk法进行数学回归分析.结果表明:白腐真菌处理硝基苯化合物符合Monod提出的一级不可逆动力学模型,通过数学处理的方法确定其动力学特征参数vm=0.8325 mg·L-1·min-1、kc=0.7525 mg·L-1.     

用紫外吸光度监测纸厂废水与悬浊固体对吸光度的影响

<正> 紫外吸光度是监测水质总有机污染的最新指标。由于该法具有仪器结构简单、操作快速方便、成本低廉、能连续监测废水中有机物浓度的相对变化等优点,近年来国外对此问题的研究日益增多。为了利用紫外吸光度进行水质的自动监测,各国已陆续研制了一些监测仪,并试用于地面水(河流、湖泊、海水等)、工业废水、生活污水等的监测工作。试验证明在254纤米(nm)的吸光度值与溶解于水中的有机物含量成正比关系。我们曾测定了苏州河水的A_(253.7)(253.7纤米的吸     

Oxi-Bioremediation of Hazardous Biosludge from Integrated Pulp and Paper Mill

The present study establishes the feasibility of decomposition of hazardous biosludge from an integrated pulp and paper mill with ozone and subsequent biodegradation of disintegrated biomass in the activated sludge process (ASP). The 16.0 ± 0.5% solubization of mixed liquor volatile suspended solids and 22.6 ± 2.3% dechlorination of AOX compounds of biosludge were observed at an ozone dosage of 43–47 mg O₃/g dry solid. More than 90% PCDD and PCDF compounds were degraded. The recycling of disintegrated sludge to ASP did not affect the performance of the process in terms of reduction in total organic carbon, CODs, color and AOX. The proliferation of filamentous organisms was controlled by ozone treatment of sludge. The biomass yield was only 0.06 g with ozone treatment, whereas the same was 0.31 g/g of CODs removal in control reactor.     

三种白腐菌对木质纤维素降解规律的初步研究

以接种量1%、接种龄7天为基准,在天然培养基及室温条件下,探讨了三种白腐菌对稻草秸秆中木质纤维素的降解动力学特性。结果表明,对木质素的降解速率桦褐孔(Inonotus sp)最高,红平菇(Pleurotus djamor)次之,白韧(Trametes sp)最低;对纤维素的降解速率与此正好相反。三菌株对木质纤维素的降解呈现一定的选择性,其中桦褐孔(Inonotus sp)对木质素的选择性降解优势最明显,选择系数达到2.99。     

Properties,Physiological Functions and Involvement of Basidiomycetous Alcohol Oxidase in Wood Degradation

Extensive research efforts have been devoted to describing yeast alcohol oxidase (AO) and its promoter region, which is vastly applied in studies of heterologous gene expression. However, little is known about basidiomycetous AO and its physiological role in wood degradation. This review describes several alcohol oxidases from both white and brown rot fungi, highlighting their physicochemical and kinetic properties. Moreover, the review presents a detailed analysis of available AO-encoding gene promoter regions in basidiomycetous fungi with a discussion of the manipulations of culture conditions in relation to the modification of alcohol oxidase gene expression and changes in enzyme production. The analysis of reactions catalyzed by lignin-modifying enzymes (LME) and certain lignin auxiliary enzymes (LDA) elucidated the possible involvement of alcohol oxidase in the degradation of derivatives of this polymer. Combined data on lignin degradation pathways suggest that basidiomycetous AO is important in secondary reactions during lignin decomposition by wood degrading fungi. With numerous alcoholic substrates, the enzyme is probably engaged in a variety of catalytic reactions leading to the detoxification of compounds produced in lignin degradation processes and their utilization as a carbon source by fungal mycelium.     

固定化白腐真菌降解焦化废水的动力学研究

采用木屑固定化白腐真菌并对焦化废水进行处理,有机物降解的宏观动力学符合一级反应动力学,动力学模式为lnS=-Kt＋lnS0。在15~30℃范围内反应速率常数K随温度升高不断增大,在30~40℃范围内反应速率常数K随温度升高不断降低,在30℃时反应速率常数最大K=0.0265 h-1。     

The Wood Preservative Potentials of Valonia,Chestnut, Tara and Sulphited Oak Tannins

This study investigated antifungal properties of four different tannins as potential environmentally friendly wood preservatives. Scots pine wood samples were impregnated with 3, 5, 10, and 15% valonia, chestnut, tara, and sulphited oak tannins, and then were exposed to brown rot fungi Coniophora puteana and Postia placenta, and white rot fungi Trametes versicolor and Pleurotus ostreatus attack to determine the best tannin type and the optimum concentration level for sufficient decay resistance. Leaching test was conducted in order to evaluate any loss in effectiveness in decay resistance due to possibility of tannin leaching. Tannins were found efficacious in suppressing brown rot fungi attacks when no leaching prior the decay test was used, however, they seemed to be ineffective against white rot fungi attacks. The lowest weight losses were obtained with valonia and chestnut tannins both for brown and white rot fungi probable related with their high ellagic tannin content.     

白腐真菌-电化学法处理黄姜废水的研究

采用单因素寻优方法考察了黄姜废水的初始浓度、pH值以及白腐真菌培养时间对降解黄姜废水的影响。结果表明,将黄姜废水稀释5倍,调节pH值到4.5,待菌种液体培养2天后加入,处理效果显著：CODCr去除率达到85%,糖分去除率达到90%以上。后续处理采用铁碳微电解法,CODCr和色度去除率都有进一步的提高。     

Fenton试剂深度处理造纸厂二级生化出水

利用Fenton试剂处理某造纸厂二级生化出水,确定出准确可行的COD测定方法。研究结果表明,在pH=5,n(H2O2)∶n(FeSO4)=2∶1,3%双氧水的投加量为2 mL/L水样,反应60 min的条件下,处理出水的COD含量降至50 mg/L以下,达到GB18918-2002国家一级A排放标准。