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表面活性剂对土壤中多环芳烃生物有效性影响的研究进展 总被引:9,自引:5,他引:9
表面活性剂能够改变多环节烃(Polycyclic aromatic hydrocarbons,PAHs)在土壤中的溶解度、吸附/解吸平衡和与土壤微生物的相互作用,从而改变PAHs的生物有效性,表面活性剂主要通过降低土壤-水之间的界面张力,增加PAHs的溶解度、促进PAHs的运输等方式来加强PAHs的生物有效性,但由于表面活性剂本身对微生物的毒害作用或无毒的表面活性剂优先作为微生物的生长基质,可能会对PAHs的生物有效性起到抑制作用,另外,表面活性剂对土壤中不同形态的PAHs生物有效性的影响不同,表面活性剂、PAHs和土壤微生物的类型浓度以及土壤的物理化学条件等都对PAHs的生物有效性有影响。 相似文献
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表面活性剂TW-80对土壤中多环芳烃生物降解的影响 总被引:41,自引:3,他引:38
以表面活性剂TW80为供试物,进行了为期150d的实验研究,并分别在30、60和150d间隔采样监测PAHs降解率。结果表明,30d后,土壤中PAHs的降解率达90%,比对照提高约30%.60d后,浓度为10000mg·kg-1表面活性剂的土壤和对照中,PAHs降解率从65.1%和60%迅速提高到93.8%和79.2%.其它处理中,PAHs的平均降解率仅比30d的结果提高4%.150d后,所有处理中PAHs的降解率均达到90%以上。可以认为,表面活性剂能提高PAHs的生物可利用性,加快PAHs的降解速率,从而减少污染暴露时间。但表面活性剂浓度过高可抑制微生物活性。研究还发现,TW80土壤中含有优势真菌。经鉴定为常见青霉、蠕形青霉、淡紫青霉和顶孢头孢霉。它们是土壤PAHs迅速降解的动因. 相似文献
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污染土壤中多环芳烃的共代谢降解过程 总被引:22,自引:0,他引:22
1 前 言多环芳烃是一类普遍存在于环境中的重要有机污染物 ,因其致癌性、致畸性、致突变性而被认为是危险物质。由于其水溶性低 ,辛醇 水分配系数高 ,因此 ,该类化合物易于从水中分配到生物体内、沉积层中。土壤成为多环芳烃的重要载体 ,多环芳烃污染土壤的生物修复也因此倍受关注。多环芳烃在土壤中有较高的稳定性 ,其苯环数与其生物可降解性明显呈负相关关系。很少有能直接降解高环数多环芳烃的微生物。研究表明 ,高分子量的多环芳烃的生物降解一般均以共代谢方式开始[1 3] 。共代谢作用可以提高微生物降解多环芳烃的效率 ,改变微生物碳… 相似文献
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多环芳烃厌氧生物降解研究进展 总被引:1,自引:1,他引:1
多环芳烃(PAHs)是环境中广泛分布的一类持久性有机污染物,对生态环境和公众健康具有极大危害。微生物降解是环境中去除多环芳烃污染的有效途径,近年来PAHs厌氧生物降解研究逐渐取代好氧降解成为人们关注的重点。本文从PAHs厌氧生物降解的研究背景出发,从不同厌氧还原反应体系、厌氧降解微生物、PAHs厌氧生物转化途径等方面阐述了PAHs厌氧生物降解的研究概况,归纳了对PAHs厌氧生物降解有积极作用的影响因素,提出了PAHs厌氧降解研究目前存在的问题,并对该领域未来研究方向作了简述和展望。希望为多环芳烃厌氧生物降解与环境修复研究与实践提供参考。 相似文献
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Effects of enrichment with phthalate on polycyclic aromatic hydrocarbon biodegradation in contaminated soil 总被引:1,自引:0,他引:1
The effect of enrichment with phthalate on the biodegradation of polycyclic aromatic hydrocarbons (PAH) was tested with bioreactor-treated and untreated contaminated soil from a former manufactured gas plant (MGP) site. Soil samples that had been treated in a bioreactor and enriched with phthalate mineralized (14)C-labeled phenanthrene and pyrene to a greater extent than unenriched samples over a 22.5-h incubation, but did not stimulate benzo[a]pyrene mineralization. In contrast to the positive effects on (14)C-labeled phenanthrene and pyrene, no significant differences were found in the extent of biodegradation of native PAH when untreated contaminated soil was incubated with and without phthalate amendment. Denaturing-gradient gel electrophoresis (DGGE) profiles of bacterial 16S rRNA genes from unenriched and phthalate-enriched soil samples were substantially different, and clonal sequences matched to prominent DGGE bands revealed that beta-Proteobacteria related to Ralstonia were most highly enriched by phthalate addition. Quantitative real-time PCR analyses confirmed that, of previously determined PAH-degraders in the bioreactor, only Ralstonia-type organisms increased in response to enrichment, accounting for 89% of the additional bacterial 16S rRNA genes resulting from phthalate enrichment. These findings indicate that phthalate amendment of this particular PAH-contaminated soil did not significantly enrich for organisms associated with high molecular weight PAH degradation or have any significant effect on overall degradation of native PAH in the soil. 相似文献
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土壤,植物样品中多环芳烃(PAHs)分析方法研究 总被引:59,自引:5,他引:59
土壤、植物和籽实样品分别用四氢呋喃、甲醇、乙酸乙酯以超声技术提取。提取液经旋转浓缩蒸发仪浓缩,经硅胶柱净化后,由高效液相色谱(HPLC)分离,萤光检测分析。对于土壤、植物和籽实样品,其方法回收率根据各个PAH化合物的理化性质不同分别为45.68-93.42、77.59-108.13和79.11-98.96%,结果表明,二氯甲烷、四氢呋喃适合作为土壤样品的提取剂;甲醇、乙酸乙酯分别适合于植物和籽实样 相似文献
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Biodegradation of polycyclic aromatic hydrocarbons (PAHs) by Cladosporium sphaerospermum isolated from an aged PAH contaminated soil 总被引:7,自引:0,他引:7
The ability of a Deuteromycete fungus, Cladosporium sphaerospermum, previously isolated from soil of an aged gas manufacturing plant, to degrade polycyclic aromatic hydrocarbons was investigated. This strain was able to degrade PAHs in non-sterile soils (average 23%), including high molecular weight PAHs, after 4 weeks of incubation. In a microcosm experiment, PAH depletion was clearly correlated to fungal establishment. In liquid culture, this strain degraded rapidly benzo(a)pyrene during its early exponential phase of growth (18% after 4 days of incubation). Among extracellular ligninolytic enzyme activities tested, only laccase activity was detected in liquid culture in the absence or in presence of benzo(a)pyrene. C. sphaerospermum might be a potential candidate for an effective bioremediation of aged PAH-contaminated soils. 相似文献
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With the focus on alternative microbes for soil-bioremediation, 18 species of litter-decomposing basidiomycetous fungi were
screened for their ability to grow on different lignocellulosic substrates including straw, flax and pine bark as well as
to produce ligninolytic enzymes, namely laccase and manganese peroxidase. Following characteristics have been chosen as criteria
for the strain selection: (i) the ability to grow at least on one of the mentioned materials, (ii) production of either of
the ligninolytic enzymes and (iii) the ability to invade non-sterile soil. As the result, eight species were selected for
a bioremediation experiment with an artificially contaminated soil (total polycyclic aromatic hydrocarbon (PAH) concentration
250 mg/kg soil). Up to 70%, 86% and 84% of benzo(a)anthracene, benzo(a)pyrene, and dibenzo(a,h)anthracene, respectively, were
removed in presence of fungi while the indigenous microorganisms converted merely up to 29%, 26% and 43% of these compounds
in 30 days. Low molecular-mass PAHs studied were easily degraded by soil microbes and only anthracene degradation was enhanced
by the fungi as well. The agaric basidiomycetes Stropharia rugosoannulata and Stropharia coronilla were the most efficient PAH degraders among the litter-decomposing species used. 相似文献
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B. T. Ashok S. Saxena K. P. Singh J. Musarrat 《World journal of microbiology & biotechnology》1995,11(6):691-692
Six polycyclic aromatic hydrocarbons [naphthalene, anthracene, phenanthrene, pyrene, chrysene and benzo(a)-pyrene] were detected in soil receiving effluents from an oil refinery. Biodegradation studies revealed a time-dependent disappearance of these polycyclic aromatic hydrocarbons when they were added to soil samples: naphthalene disappeared completely in 60 days, whereas phenanthrene, anthracene, pyrene, chrysene and benzo(a)pyrene decreased by 87%, 34%, 21%, 5% and 40%, respectively, in 120 days.B.T. Ashok and J. Musarrat were and S. Saxena is with the Interdisciplinary Biotechnology Unit, A.M.U., Aligarh-202002, Uttar Pradesh, India. K.P. Singh is with the Environmental Chemistry Section, Industrial Toxicology Research Centre, M.G. Road, Lucknow-226001, Uttar Pradesh, India. B.T. Ashok is now with the Department of Biochemistry, J.N. Medical College, A.M.U., Aligarh-202002, Uttar Pradesh, India. J. Musarrat is now with the Department of Radiology and Blochemistry Program. The Ohio State University, Columbus, OH 43210, USA. 相似文献
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多环芳烃类化合物在土壤上的吸附 总被引:31,自引:0,他引:31
研究了几种多环芳烃化合物在土壤上的吸附行为.通过一个连续投药-取样试验装置,在没有任何其它有机试剂干扰的情况下,测定了荧蒽与菲在土壤上的吸附量.研究表明,这两种多环芳烃化合物在土壤上的吸附量与土壤有机质含量之间呈显著相关.对多环芳烃化合物的分子结构及理化特性,如辛醇-水分配系数、溶解度等参数与LogKoc关系的研究发现多环芳烃化合物的LogKoc与化合物的水溶性、辛酸-水分配系数以及分子结构中的苯环数线性相关. 相似文献
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The objectives of this work were to isolate the microorganisms responsible for a previously observed degradation of polycyclic
aromatic hydrocarbons (PAH) in soil and to test a method for cleaning a PAH-contaminated soil. An efficient PAH degrader was
isolated from an agricultural soil and designated as Mycobacterium LP1. In liquid culture, it degraded phenanthrene (58%), pyrene (24%), anthracene (21%) and benzo(a)pyrene (10%) present in mixture (initial concentration 50 μg ml−1 each) and phenanthrene (92%) and pyrene (94%) as sole carbon sources after 14 days of incubation at 30°C. In soil, Mycobacterium LP1 mineralised 14C-phenanthrene (45%) and 14C-pyrene (65%) after 10 days. The good ability of this Mycobacterium was combined with the benzo(a)pyrene oxidation effect obtained by 1% w/w rapeseed oil in a sequential treatment of a PAH-spiked soil (total PAH concentration
200 mg kg−1). The first step was incubation with the bacterium for 12 days and the second step was the addition of the rapeseed oil after
this time and a further incubation of 22 days. Phenanthrene (99%), pyrene (95%) and anthracene (99%) were mainly degraded
in the first 12 days and a total of 85% of benzo(a)pyrene was transformed during the whole process. The feasibility of the method is discussed. 相似文献
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污灌土壤中多环芳烃(PAHs)的积累与动态变化研究 总被引:43,自引:5,他引:43
对污灌土壤中 1 4种多环芳烃的分析表明 ,各灌区土壤中 PAHs的积累一般以渠首最高 ,渠中次之 ,渠尾含量与对照相当 .但在沈抚石油灌区上、中和下游土壤中均有PAHs的积累 .此外 ,水稻生长期污灌可明显增加土壤中 PAHs的总量 ,各单一污染物的增、减趋势有所不同 . 相似文献
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非流体介质中多环芳烃污染的微生物固定化修复技术 总被引:9,自引:2,他引:9
非流体介质中多环芳烃(PAHs)污染的修复是目前环境工作者所面临的艰巨而紧迫的任务.由于非流体介质环境的特殊性,常规修复方法难以高效地发挥作用,传统微生物修复技术采用的游离微生物也存在许多弊端.而微生物固定化能大幅度地提高参加反应的微生物浓度,避免优势菌受土著菌的恶性竞争,增强微生物的耐环境冲击性.微生物固定化技术在一定程度上克服了传统工艺的不足,因而广泛应用于流体介质(废水等)和半流体介质(泥浆等)环境污染的修复.在概述固定化微生物技术的特点和分析国内外研究进展的基础上,指出将该技术应用于非流体介质中PAHs污染的原位修复领域的可行性,并论述了需要解决的关键科学问题,提出了利用微生物固定化技术修复非流体介质中PAHs污染的未来研究课题. 相似文献
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植物法生物修复PAHs和矿物油污染土壤的调控研究 总被引:62,自引:7,他引:62
选择苜蓿草为供试植物,以污染物含量水平、专性细菌和真菌及有机肥为调控因子,进行了植物法生物修复多环芳烃(PAHs)和矿物油污染土壤的调控研究。结果表明,PAHs和矿物油的降解率与有机肥含量呈正相关,增加有机肥5%,可提高矿物油降解率17.6%~25.6%,PAHs降解率9%.在植物存在条件下,土壤微生物降解功能增强。多环芳烃总量的平均降解率比无植物对照土壤提高2.0%~4.7%.投加特性降解真菌可不同程度地提高土壤PAHs总量和矿物油的降解率。真菌对萤蒽、芘和苯(a)蒽/(艹屈)的降解有明显促进作用。而细菌能明显提高苊稀/芴、蒽和苯(a)萤蒽/苯(k)萤蒽的降解率。 相似文献