Effects of biosurfactants on assays of PCB congeners in transgenic arabidopsis plants carrying a recombinant guinea pig AhR-mediated GUS reporter gene expression system

The transgenic Arabidopsis plants carrying a recombinant guinea pig (g) aryl hydrocarbon receptor (AhR)-mediated β-glucuronidase (GUS) reporter gene expression system were generated for assays of polychlorinated biphenyl (PCB) congeners. The selected transgenic Arabidopsis plant XgD2V11-6 exhibited a correlation between uptake of PCB126 and PCB126-induced GUS activity. Also, the plants showed induced GUS activity towards the supplemental indole 3-acetic acid (IAA). Thus, the GUS assay may reflect induction by both endogenous and exogenous AhR ligands. When biosurfactants, MEL-B, produced in the culture of yeast isolated from plants were used for assays of PCB congeners in the transgenic Arabidopsis plants, they showed marked PCB126 dose-dependent and toxic equivalency factor (TEF) dependent GUS activities. The effects of biosurfactants were clearer when the plants were cultivated on soils containing PCB congeners for 7 days as compared with on soils for 3 days as well as in the medium for 3 days. Threfore, it was estimated that biosurfactants form micellae with PCB congeners, which are easily uptaken by the plants in a mode of passive diffusion, transport into the aerial parts and then induce GUS activity.     

Fingerprinting of Gasoline and Coal Tar NAPL Volatile Hydrocarbons Dissolved in Groundwater

Accidental spills and chronic leaks of fuel oil or other hydrocarbon material (e.g., coal tar) often result in subsurface accumulation of nonaqueous phase liquid (NAPL), which can be a subsequent source of contamination in groundwater. Linking hydrocarbons in groundwater to a source NAPL has been difficult when using standard target analytes (e.g., BTEX) because of differences in partitioning properties of the analytes between the source NAPL and groundwater. Because aqueous solubility is predicted to be the controlling influence in the partitioning of hydrocarbons from NAPL to groundwater, a solubility-based approach to matching dissolved hydrocarbons in groundwater to their source NAPL has been developed and validated for two sites with commonly encountered types of NAPL contamination. Specifically, a gasoline LNAPL and a coal tar DNAPL from two separate sites (West Virginia and California) and groundwater interfaced with these NAPLs were analyzed for approximately 50 gasoline-range hydrocarbons consisting of paraffin, isoparaffin, (mono-) aromatic, naphthene, and olefin compounds (PIANO). Solubility characteristics of selected alkyl aromatic hydrocarbons from the PIANO analysis were used to identify a set of diagnostic hydrocarbons, expressed as hydrocarbon ratios, which were found to be useful in distinguishing the source(s) of hydrocarbons in groundwater. At the West Virginia site, the diagnostic ratios in a downgradient groundwater sample were similar to those of a gasoline NAPL at that site, indicating the source of hydrocarbons to the groundwater was the upgradient gasoline NAPL. The diagnostic ratios of the groundwater in contact with the gasoline NAPL and the remote groundwater were also similar, providing evidence that the diagnostic ratios were retained during transport in the aquifer. At the California site, diagnostic ratios in a cross-gradient groundwater sample differed from those of the coal tar NAPL at that site, indicating that the remote groundwater hydrocarbons did not originate from the coal tar contamination. Environmental factors such as selective degradation of specific isomers and various geological conditions (e.g., soil mineralogy, and organic content) may confound the application of this solubility-based fingerprinting approach. Thus, it is recommended that multiple diagnostic pairs be simultaneously evaluated when considering this fingerprinting approach for specific sites and product types.     

响应面法优化聚丙烯酸/腐殖酸/累托石吸附剂的制备条件

以累托石、丙烯酸及腐殖酸为原料制备出能同时吸附重金属和多环芳烃的吸附剂聚丙烯酸/腐殖酸/累托石,采用响应面试验设计法优化吸附剂的制备条件。利用Design Expert软件,建立了预测吸附剂对Cd2+、菲吸附量的二次回归模型,对回归模型进行了方差分析,并确定了吸附剂的最佳制备条件。结果表明,二次回归模型能较好地模拟Cd2+、菲的吸附量与影响因子丙烯酸中和度、引发剂量和交联剂量之间的关系。各因子对Cd2+吸附量的影响次序为:交联剂量>引发剂量>丙烯酸中和度;对菲吸附量的影响次序为引发剂量>交联剂量>丙烯酸中和度。吸附剂的最佳制备条件为:累托石、丙烯酸和腐殖酸三者的质量比为65∶30∶5,丙烯酸中和度、引发剂量和交联剂量分别为75.16%、2.57%和0.44%。在此优化条件下制备的吸附剂对Cd2+和菲的吸附量分别为170.19 mg/g和7.36 mg/g。     

微生物法处理海上钻井废钻井液

微生物法适用于海上钻井含油废弃物的处理。通过多次对菌株采集、分离、纯化和培养驯化,选育得到了3株对石油烃类有很好降解效果的石油类降解菌;确定了石油类降解菌适宜的生化处理条件:最佳生长及原油降解温度为50℃、最佳生长及原油降解酸碱性环境为pH=6.0、最佳菌株接种量2%、最佳原油初始浓度为500mg/L。处理后的含油废弃钻井液含油量基本稳定在2mg/L以下,降解率达98%以上。     

绿色油田建设中存在的问题及对策探讨

文章分析了石油开发对环境的影响,提出了绿色油田建设的必要性与重要性。通过对国内外绿色油田建设现状的调研与对比,总结出目前我国建设绿色油田的瓶颈,提出了建议与对策,并展望了建设绿色油田的前景。     

Rural development and ecological management of endogenous resources: the case of mountain olive groves in Los Pedroches comarca (Spain)

In this paper, we explore the dissemination potential of organic farming in Andalucía, using the case of Olivarera de los Pedroches, a small farmer cooperative. This will be done in the search for an agroecological strategy in the olive tree organic agricultural sector. A comparative analysis of organic and conventional olive oil production is made: both in economic terms, and regarding employment creation, taking into account its environmental benefits. This will permit us to shed light on certain elements necessary in the design of rural policies linked to this economic sector, and in the family farming social stratum. After a brief analysis of the Andalucían inequality structure in rural areas—both historically and at present times—this work presents the following issues: (i) a systematic characterization of European olive cultivation, with special reference to the Spanish and Andalucían situations; (ii) an exploration of the socio-economic impact of the case study within the context of the major actors involved, and their relations in terms of its reproducibility, taking into account their relationships with institutional and policy arrangements. Organic agriculture in Spain has developed slowly since 1995—the year in which aid towards this type of production began to be established—and, at present, begins to show an exponential increase. Many farmers began the transition to ecological handling of olive groves. Consequently, the organic management of the olive groves and the sale of organic olive oil can be a stimulus to farmers to increase their profits. Hence, it can be a fundamental pillar on which to establish rural development in areas with a high level of importance concerning this crop. In this work, data clearly show that, in spite of high costs, organic olive farming has advantages over conventional agriculture in terms of incomes and employment. Copyright © 2001 John Wiley & Sons, Ltd.     

Bio-Ethanol Production from Non-Food Parts of Cassava (<Emphasis Type="Italic">Manihot esculenta</Emphasis> Crantz)

Global climate issues and a looming energy crisis put agriculture under pressure in Sub-Saharan Africa. Climate adaptation measures must entail sustainable development benefits, and growing crops for food as well as energy may be a solution, removing people from hunger and poverty without compromising the environment. The present study investigated the feasibility of using non-food parts of cassava for energy production and the promising results revealed that at least 28% of peels and stems comprise dry matter, and 10 g feedstock yields >8.5 g sugar, which in turn produced >60% ethanol, with pH ≈ 2.85, 74-84% light transmittance and a conductivity of 368 mV, indicating a potential use of cassava feedstock for ethanol production. Thus, harnessing cassava for food as well as ethanol production is deemed feasible. Such a system would, however, require supportive policies to acquire a balance between food security and fuel.     

The structure of the fire fighting foam surfactant Forafac®1157 and its biological and photolytic transformation products

For several decades, perfluorooctane sulfonate (PFOS) has widely been used as a fluorinated surfactant in aqueous film forming foams used as hydrocarbon fuel fire extinguishers. Due to concerns regarding its environmental persistence and toxicological effects, PFOS has recently been replaced by novel fluorinated surfactants such as Forafac®1157, developed by the DuPont company. The major component of Forafac®1157 is a 6:2 fluorotelomer sulfonamide alkylbetaine (6:2 FTAB), and a link between the trade name and the exact chemical structure is presented here to the scientific community for the first time. In the present work, the structure of the 6:2 FTAB was elucidated by ¹H, ¹³C and ¹⁹F nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry. Moreover, its major metabolites from blue mussel (Mytilus edulis) and turbot (Scophthalmus maximus) and its photolytic transformation products were identified. Contrary to what has earlier been observed for PFOS, the 6:2 FTAB was extensively metabolized by blue mussel and turbot exposed to Forafac®1157. The major metabolite was a deacetylated betaine species, from which mono- and di-demethylated metabolites also were formed. Another abundant metabolite was the 6:2 fluorotelomer sulfonamide. In another experiment, Forafac®1157 was subjected to UV-light induced photolysis. The experimental conditions aimed to simulate Arctic conditions and the deacetylated species was again the primary transformation product of 6:2 FTAB. A 6:2 fluorotelomer sulfonamide was also formed along with a non-identified transformation product. The environmental presence of most of the metabolites and transformation products was qualitatively demonstrated by analysis of soil samples taken in close proximity to an airport fire training facility.     

Dioxin-like activity in environmental and human samples from Greenland and Denmark

Dioxins and dioxin-like (DL) compounds are some of the most toxic chemicals being highly persistent in the environment. The toxicological effects of dioxins are mediated via the aryl hydrocarbon receptor (AhR). Compounds of diverse structure and lipophility can bind and activate AhR. The AhR transactivation bioassay is utilized in an array of projects to study the AhR-mediated activities of individual chemicals and mixtures and for epidemiological purposes.This review summarizes a series of studies regarding the DL-activity of single compounds and complex compound mixtures in the environment and humans.We found that some pesticides, plasticizers and phytoestrogens can activate the AhR, and the combined effect of compounds with no or weak AhR potency cannot be ignored.The significant DL-activity in the wastewater effluent indicates the treatment is not sufficient to prevent contamination of surface waters with dioxins. Our results from human studies suggest that the serum DL-activity reflect the complex mixture of persistent organic pollutants (POPs). Greenlandic Inuit had lower serum DL-activity level compared to Europeans, probably due to long distance from the dioxin sources and UV degradation of the high potent dioxin and/or the inhibitory effect of the high level of non-DL POPs. Selective bioaccumulation of PCBs in the food chain may contribute to the negative correlation between serum POPs and DL-activity observed in Greenlandic Inuit.Hence the AhR transactivation bioassay provides a cost-effective and integrated screening tool for measurement of the DL-activity in human, environmental and commercial samples.     

壬基酚降解菌产酶条件的优化

通过单因素试验和正交试验确定了实验室保藏的壬基酚降解菌株沙雷氏菌(Serratiasp.LJ)的最佳产酶条件:以壬基酚、硫酸铵为碳源、氮源,培养基初始pH为6.8,培养温度为30℃,种子活化时间为24h,接种量为3%(体积分数)。在此条件下培养72h后,最高酶活力为1.314IU/mL,是优化前的1.77倍。