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61.
Christos P. Papaneophytou Anastasia A. Pantazaki 《Journal of Polymers and the Environment》2011,19(4):876-886
A novel affinity chromatographic material, which is composed of silica matrix, coated with polyhydroxybutyrate (PHB) powder,
suitable for the purification of PHB depolymerases, was developed. The surface morphology of the PHB-silica coated particles
(silica-PHB composite particles) was examined by scanning electron microscopy and revealed a successful uniform coating of
silica particles with PHB. Moreover, the complex of these materials retained its homogeneity even after incubation at 80 °C
for 6 h, whereas the strong binding of PHB on silica surface was further verified by thermal gravimetric analysis and by PHB
extraction- from silica surface- experiments. This novel material was demonstrated to be suitable for both, the one-step on-batch
and on-column purification of Thermus thermophilus extracellular PHB depolymerase. The enzyme exhibited higher affinity against the composite of silica-PHB particles than PHB
powder, since the one-step purification-fold and the overall recovery of the enzyme were 2.8 and 4 times higher respectively,
in the first case. Reusability of the silica-PHB composites particles was examined by determining the recoveries of PHB depolymerase.
The enzyme recoveries were ranged from 30 to 35% for the first five uses, whereas for further uses recoveries gradually dropped
to 15–18% indicating that the particles could be used repeatedly for five times. This material could be also a suitable support
for lipases or other proteins that exhibit strong affinity to hydrophobic materials. 相似文献
62.
Passive sampling of selected endocrine disrupting compounds using polar organic chemical integrative samplers 总被引:3,自引:0,他引:3
Two types of polar organic chemical integrative samplers (pharmaceutical POCIS and pesticide POCIS) were examined for their sampling efficiency of selected endocrine disrupting compounds (EDCs). Laboratory-based calibration of POCISs was conducted by exposing them at high and low concentrations of 14 EDCs (4-alkyl-phenols, their ethoxylate oligomers, bisphenol A, selected estrogens and synthetic steroids) for different time periods. The kinetic studies showed an integrative uptake up to 28 days. The sampling rates for the individual compounds were obtained. The use of POCISs could result in an integrative approach to the quality status of the aquatic systems especially in the case of high variation of water concentrations of EDCs. The sampling efficiency of POCISs under various field conditions was assessed after their deployment in different aquatic environments. 相似文献
63.
Vinke Kira Martin Maria A. Adams Sophie Baarsch Florent Bondeau Alberte Coumou Dim Donner Reik V. Menon Arathy Perrette Mahé Rehfeld Kira Robinson Alexander Rocha Marcia Schaeffer Michiel Schwan Susanne Serdeczny Olivia Svirejeva-Hopkins Anastasia 《Regional Environmental Change》2017,17(6):1569-1583
Regional Environmental Change - This paper reviews the current knowledge of climatic risks and impacts in South Asia associated with anthropogenic warming levels of 1.5–4 °C... 相似文献
64.
Partitioning of endocrine disrupting compounds in inland waters and wastewaters discharged into the coastal area of Thessaloniki,Northern Greece 总被引:1,自引:0,他引:1
Anastasia Arditsoglou Dimitra Voutsa 《Environmental science and pollution research international》2010,17(3):529-538
Background, aim, and scope
In the Water Framework Directive 2000/60/EC, environmental objectives for the proper quality of inland, surface, transitional, coastal, and ground waters have been set. Member states are required to identify chemical pollutants of significance in the water bodies, to establish emission control measures, and to achieve quality standards. A specific category of pollutants are the compounds that may possess endocrine-related functions known as endocrine disrupting compounds (EDCs). This means that member states have the obligation to take action in order to prevent human exposure to these compounds via aquatic environment. The objective of this research was to study the occurrence and distribution of phenolic and steroid EDCs in inland waters and wastewaters discharged in the area of Thermaikos Gulf, Thessaloniki, Northern Greece. 相似文献65.
Nikolaou AD Golfinopoulos SK Lekkas TD Kostopoulou MN 《Environmental monitoring and assessment》2004,93(1-3):301-319
Chlorination is the most widely used technique for disinfection of drinking water. A consequence of chlorination is the formation of Disinfection By-Products (DBPs). The formation of DBPs in drinking water results from the reaction of chlorine with naturally occurring organic materials, principally humic and fulvic acids. This paper focuses on the effect of humic substances on the formation of twenty-four compounds belonging to different categories of DBPs. This investigation was conducted in two water treatment plants in Greece, Menidi and Galatsi, from July 1999 to April 2000. Humic substances were determined by the diethylaminoethyl (DEAE) method with subsequent UV measurement. The techniques used for the determination of DBPs were liquid-liquid extraction, gas chromatography and mass spectrometry. The concentrations of DBPs were generally low. Total trihalomethanes (TTHMs) ranged from 5.1 to 24.6 microg L(-1), and total haloacetic acids (HAAs) concentration ranged from 8.6 to 28.4 microg L(-1), while haloaketones (HKs) and chloral hydrate (CH) occurred below 1 microg L(-1). The content of humic substances was found to influence the formation of DBPs and especially TTHMs, trichloroacetic acid (TCA), dibromoacetic acid (DBA), CH, 1,1-dichloropropanone (1.1-DCP) and 1,1,1-trichloropropanone (1,1,1-TCP). Seasonal variation of TTHMs and HAAs generally followed that of humic substances content with peaks occurring in autumn and spring. The trends of 1,1-DCP, 1,1,1-TCP and CH formation seemed to be in contrast to TTHMs and HAAs. Trends of formation of individual compounds varied in some cases, probably due to influence of parameters other than humic substances content. Statistical analysis of the results showed that the concentrations of TTHMs, CH, 1,1-DCP, 1,1,1-TCP, TCA and DBA are strongly affected from humic substances content (at 0.01 confidence level). The opposite is true for dichloroacetic acid (DCA) concentration. Humic substances also vary to a statistically significant degree during different months, as well as the concentrations of TTHMs, CH, 1,1-DCP, 1,1,1-TCP, TCA and DCA. The variance of DBA was not statistically significant. Regarding the effect of sampling station, humic substances content showed no statistically significant difference between the two raw water sources studied. 相似文献