31 stran : barevné ilustrace ; 21 cm
Studie, která se zaměřila na chemickou analýzu vody kontaminované pesticidy a léčivy v Evropě.
- MeSH
- chemické látky znečišťující vodu analýza MeSH
- chemické znečištění vody analýza MeSH
- nežádoucí účinky léčiv MeSH
- pesticidy analýza toxicita MeSH
- voda analýza MeSH
- Publikační typ
- práce podpořená grantem MeSH
- Geografické názvy
- Evropa MeSH
- Konspekt
- Znečištění a poškození životního prostředí
- NLK Obory
- environmentální vědy
- NLK Publikační typ
- studie
- brožury
Předložený příspěvek demonstruje výskyt bakterií rodu Ralstonia v různých výrobnících čištěné vody (Aqua purificata) i v případech, kdy celkové počty aerobních mikroorganismů splňují požadavky Českého lékopisu a zároveň ukazuje na možné rozdíly ve způsobech detekce aerobních organotrofních mikroorganismů (různá média, různý typ inokulace apod.). Výskyt bakterií rodu Ralstonia je v čištěné vodě běžný, a přestože tento typ vody nemusí být sterilní, při využití v řadě případů (věk cílové skupiny pacientů, rizikové diagnózy, podání na porušenou kůži či na sliznici) by neměl obsahovat potenciálně patogenní mikroorganismy.
The study focuses on the occurrence of bacteria of the genus Ralstonia in various apparatuses producing of purified water (Aqua purificata) even in cases where the total numbers of aerobic microorganisms meet the requirements of the Czech Pharmacopoeia and also shows possible differences in detection methods of aerobic organotrophic microorganisms (media, inoculation). The presence of Ralstonia is common in purified water, and although this type of water may not be sterile, it should not contain potentially pathogenic microorganisms when used in specific cases (age of patient, riskful diagnosis, application to damaged skin or mucosa).
- MeSH
- mikrobiologie vody MeSH
- Ralstonia * izolace a purifikace patogenita MeSH
- sterilizace MeSH
- voda * analýza MeSH
- Publikační typ
- práce podpořená grantem MeSH
A miniaturized extraction/preconcentration method based on an aqueous biphasic system (μ-ABS) was developed with reagents commonly used as food additives: cholinium chloride (ChCl) as main extraction phase, K2HPO4 as salting-out agent, and water as the main component (being the sample for analyses). With the aim of obtaining high enrichment factors, miniaturization, and adequate analytical performance, a point in the biphasic region with the lowest amount of ChCl was selected, corresponding to 1.55% (w/w) of ChCl, 59.5% (w/w) of K2HPO4, and 38.95% (w/w) of water. The green μ-ABS (attending to its main elements and performance mode) was used in combination with high-performance liquid chromatography with diode-array detection (HPLC-DAD) for the determination of 9 personal care products in wastewater samples. The μ-ABS-HPLC-DAD method showed high enrichment factors (up to 100), and quantitative extraction efficiencies for those compounds containing OH groups in their structure, which can undergo hydrogen bonding with ChCl. Thus, limits of quantification down to 0.8 µg·L-1 and extraction efficiencies between 66.4 and 108% (concentration levels of 1.3 and 13 µg·L-1) were reached for the group of parabens and the UV-filter benzophenone-3. The method is characterized by the use of non-harmful reagents and the absence of organic solvents in the entire sample preparation procedure, while being simple, low-cost, easily compatible with HPLC, and highly efficient.
- MeSH
- chemické látky znečišťující vodu analýza MeSH
- chloridy analýza MeSH
- fosfáty analýza MeSH
- kosmetické přípravky analýza MeSH
- miniaturizace * MeSH
- odpadní voda chemie MeSH
- reprodukovatelnost výsledků MeSH
- rozpouštědla chemie MeSH
- voda analýza MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Publikační typ
- časopisecké články MeSH
Cíl: Cílem práce je ověřit účinek několika biocidů využívaných v ČR pro zabezpečení teplé vody proti výskytu legionel. Do pokusu byly zařazeny jednoznačně chemicky definované látky (chlornan sodný, oxid chloričitý, chloritany a chlorečnany) a pak směsné přípravky (DUOZON, SANOSIL). Metody: Pro experimenty byl jako základní testovací materiál použit přírodní izolát Legionella pneumophila, sg 1, zachycený při běžném vyšetřování vzorků teplé vody. Sbírkové kmeny jsou pro tyto pokusy nevhodné, protože pasážemi na pevných půdách ztrácejí některé vlastnosti. Testovací kmen byl ve vodném roztoku (ve vodovodní vodě) a v příslušném ředění vystaven vybraným koncentracím biocidů po dobu 60 minut, aby bylo možno stanovit nejnižší účinné koncentrace, při kterých planktonní formy legionel hynou. Počet legionel ve vzorcích před a po expozici byl stanoven podle ČSN EN ISO 11731. Koncentrace biocidů byla měřena na počátku každého pokusu. Výsledky: Podle výsledků pokusů jsou testované biocidy srovnány podle nejnižší účinné koncentrace, v pořadí: 1. oxid chloričitý (0,2 mg/l), 2. chlornan sodný a DUOZON (0,7 mg/l jako Cl), 3. SANOSIL (100 mg/l), 4. chloritan sodný (600 mg/l), 5. chlorečnan sodný (1000 mg/l). Závěr: Testované biocidy prodávané na českém trhu prokázaly v laboratorním pokusu způsobilost ničit legionely. Pokusem byly stanoveny nejnižší koncentrace, které ještě poskytují účinnou prevenci legionel v teplé vodě.
Objective: The objective of the paper was to verify the effects of several biocides used in the Czech Republic for prevention of legionella in hot water systems. Selected biocides were tested (sodium hypochlorite, chlorine dioxide, chlorites and chlorates) as well as compounds (DUOZON, SANOSIL). Method: A natural strain of Legionella pneumophila, sg 1, isolated during regular testing of warm water samples was used for testing. Because control strains lose some of their properties in storage they are inappropriate for this type of testing. The testing strain was exposed to varying concentrations of biocides in tap water for a 60 minute period to determine the lowest possible concentration at which legionella plankton forms were destroyed. Legionella counts prior to and after exposure were determined according to CSN EN ISO 11731. Biocide concentrations were measured at the start of each test. Results: Tested biocides were compared according to their lowest effective concentrations: 1) chlorine dioxide (0.2 mg/l), 2) sodium hypochlorite and DUOZON (0.7 mg/l as Cl), 3) SANOSIL (100 mg/l), 4) trisodium phosphate (600 mg/l) and, 5) sodium chlorate (1,000 mg/l). Conclusion: The tested biocides commercially available in CR were at constant dosing adequately effective as prevention against legionella in warm water.
Although pharmaceuticals are frequently studied contaminants, their fate in the environment is still not completely clear. During a one year study, a complex approach including water, sediment and fish sampling was used to describe the behaviour of pharmaceuticals and their metabolites (PTMs) in the environment. Eighteen pharmaceuticals and seven of their metabolites were determined in a pond used for the tertiary treatment of wastewater effluent. A liquid chromatography-tandem mass spectrometry method was applied to determine the PTMs concentrations in all matrices. Seasonal variations in concentrations were evaluated. The partitioning of contaminants between pond compartments was estimated by means of solid water distribution coefficients (Kd) and bioaccumulation factors (BAF) for the livers of fish. Kd values were almost stable throughout the year, which may be a sign of the continuous transport of PTMs between water and sediment under the experimental conditions. Almost all of the studied compounds, with exception of sertraline (BAF of 6200), were found to not be bioaccumulative in fish livers. The pond removal efficiency was calculated for all PTMs, and favourable conditions for natural pharmaceutical removal were proposed. Further aspects regarding fish pharmaceutical exposure need to be studied.
- MeSH
- chromatografie kapalinová MeSH
- geologické sedimenty analýza MeSH
- léčivé přípravky MeSH
- odpadní voda analýza MeSH
- roční období MeSH
- ryby metabolismus MeSH
- voda analýza MeSH
- vodní organismy MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The proposed HPLC method using solely or nearly 100% aqueous mobile buffer as mobile phase offers fast determination of dissociation constant for compounds in relatively wide range of lipophilicity (log P from -2.26 to 2.26). The dissociation constant value for simpler chemical compounds can be determined via only 8 chromatographic runs. The number of needed chromatographic separations depends on the structural complexity of the tested compound. Moreover, the proposed method does not require a measurement of Yasuda-Shedlovsky extrapolation that includes several pKa determinations in solutions with different methanol content which speeds up considerably the procedure. The methodology is suitable for evaluation of large series of drug candidates, which can be present as complex mixtures and in small amounts.
Procedures for the extraction-spectrophotometric determination of tris(2-chloroethyl)amine, an alkylating agent known as a drug as well as a chemical warfare agent (nitrogen mustard HN-3), with 7 acid-base indicators of a triphenylmethane lactone type, phthaleins, were developed. Representatives of phthaleins without an oxygen bridge (thymolphthalein, o-cresolphthalein, naphtholphthalein) and with an oxygen bridge (fluorescein, 2',7'-dichlorofluorescein, eosin B and eosin Y) were used. The methods were based on the formation of ion pair complexes. Chloroform was used as a non-polar solvent for an extraction. The conditions to determine were optimized for the optimal pH of the buffer and the concentration of a phthalein as a reagent. The dependence on the reaction time in a water phase and the stoichiometry of extraction products were studied. The detection limits and the limits of the determination of separate procedures and conditional extraction constants were determined. Comparison with the spectrophotometric method of the group determination of alkyl halides and acyl halides using alkaline ethanol-water solution of thymolphthalein, the so-called T-135 agent, was conducted. While studying the selectivity, the possible interference of bis(2-chloroethyl)sulphide and 3 nitrogen mustards in the proposed procedures were verified. Copyright © 2016 John Wiley & Sons, Ltd.
- MeSH
- alkylační látky analýza izolace a purifikace MeSH
- chemické bojové látky analýza izolace a purifikace MeSH
- fenolftaleiny chemie MeSH
- koncentrace vodíkových iontů MeSH
- limita detekce MeSH
- pufry MeSH
- sloučeniny dusíkatého yperitu analýza izolace a purifikace MeSH
- spektrofotometrie metody MeSH
- voda analýza MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
BACKGROUND: Chickpea (Cicer arietinum L.) is a widely cropped pulse and an important source of proteins for humans. In Mediterranean regions it is predicted that drought will reduce soil moisture and become a major issue in agricultural practice. Nitrogen (N)-fixing bacteria and arbuscular mycorrhizal (AM) fungi have the potential to improve plant growth and drought tolerance. The aim of the study was to assess the effects of N-fixing bacteria and AM fungi on the growth, grain yield and protein content of chickpea under water deficit. RESULTS: Plants inoculated with Mesorhizobium mediterraneum or Rhizophagus irregularis without water deficit and inoculated with M. mediterraneum under moderate water deficit had significant increases in biomass. Inoculation with microbial symbionts brought no benefits to chickpea under severe water deficit. However, under moderate water deficit grain crude protein was increased by 13%, 17% and 22% in plants inoculated with M. mediterraneum, R. irregularis and M. mediterraneum + R. irregularis, respectively. CONCLUSION: Inoculation with N-fixing bacteria and AM fungi has the potential to benefit agricultural production of chickpea under water deficit conditions and to contribute to increased grain protein content. © 2017 Society of Chemical Industry.
- MeSH
- Bacteria růst a vývoj MeSH
- Cicer chemie růst a vývoj metabolismus mikrobiologie MeSH
- dusík metabolismus MeSH
- fyziologie bakterií * MeSH
- houby růst a vývoj fyziologie MeSH
- mykorhiza fyziologie MeSH
- očkovadla agrotechnická fyziologie MeSH
- rostlinné proteiny analýza metabolismus MeSH
- symbióza MeSH
- voda analýza metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
An advanced optical biosensor was developed based on the enzymatic reaction with halogenated aliphatic hydrocarbons that is accompanied by the fluorescence change of pH indicator. The device is applicable for the detection of halogenated contaminants in water samples with pH ranging from 4 to 10 and temperature ranging from 5 to 60°C. Main advantages of the developed biosensor are small size (60×30×190mm(3)) and portability, which together with short measurement time of 1min belong to crucial attributes of analytical technique useful for routine environmental monitoring. The biosensor was successfully applied for the detection of several important halogenated pollutants under laboratory conditions, e.g., 1,2-dichloroethane, 1,2,3-trichloropropane and γ-hexachlorocyclohexane, with the limits of detection of 2.7, 1.4 and 12.1mgL(-1), respectively. The continuous monitoring was demonstrated by repetitive injection of halogenated compound into measurement solution. Consequently, field trials under environmental settings were performed. The presence of 1,2-dichloroethane (10mgL(-1)) was proved unambiguously on one of three potentially contaminated sites in Czech Republic, and the same contaminant was monitored on contaminated locality in Serbia. Equipped by Global Positioning System, the biosensor was used for creation of a precise map of contamination. Concentrations determined by biosensor and by gas chromatograph coupled with mass spectrometer exhibited the correlation coefficient of 0.92, providing a good confidence for the routine use of the biosensor system in both field screening and monitoring.
- MeSH
- Bacteria enzymologie MeSH
- biosenzitivní techniky přístrojové vybavení MeSH
- chemické látky znečišťující vodu analýza metabolismus MeSH
- chlorované uhlovodíky analýza metabolismus MeSH
- fluorescence MeSH
- fluorescenční spektrometrie přístrojové vybavení MeSH
- hydrolasy metabolismus MeSH
- monitorování životního prostředí přístrojové vybavení MeSH
- voda analýza MeSH
- Publikační typ
- časopisecké články MeSH
