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1.
J Environ Manage ; 281: 111804, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33385910

ABSTRACT

Freshwater scarcity is a global concern, not just in countries with limited water resources, and wastewater reuse is becoming an essential necessity. Beer is the fifth-most widely consumed beverage in the world and breweries are a major industrial water consumer. Within this study, the long-term performance of a modular pilot scale plant reusing brewery wastewater was investigated. The system consisted of a flotation device, a membrane bioreactor (MBR), an ultrafiltration (UF) and a reverse osmosis (RO) system. The system was fed with wastewater from the effluent of a full-scale anaerobic reactor. The combination of flotation device and MBR removed chemical oxygen demand (COD) by 93.6%. The subsequent UF and RO removed remaining organic load and inorganic components and process water was produced, whereby drinking water quality was achieved. A yield of 63% was reached with the pilot plant. Based on the results, a base case cost estimate was carried out for a full-scale application, taking into account the actual hydraulic load of the brewery. In order to predict the uncertainties of cost-sensitive factors, the specific costs for sludge disposal, electrical energy, freshwater supply and wastewater disposal as well as membrane lifespan and yield of the RO unit were expressed by probability distributions. Using the Monte Carlo method with 75,000 iterations, the probability distributions for the costs and economic viability of reusing brewery wastewater were calculated. The estimate found that reusing brewery wastewater can be economically viable in 77.2% of simulated cases showing the strongest dependency on costs for wastewater disposal.


Subject(s)
Wastewater , Water Purification , Bioreactors , Cost-Benefit Analysis , Membranes, Artificial , Osmosis , Waste Disposal, Fluid
2.
J Anal Methods Chem ; 2016: 7201740, 2016.
Article in English | MEDLINE | ID: mdl-26949562

ABSTRACT

The main aim of this study was to enrich glycyrrhizic acid ammonium salt known as one of the main compounds of licorice roots (Glycyrrhiza glabra L.) by isoelectric focused adsorptive bubble separation technique with different foaming agents. In the experiments, four bubble separation parameters were used with ß-lactoglobulin, albumin bovine, and starch (soluble) preferred as foaming agents and without additives. The enrichment of glycyrrhizic acid ammonium salt into the foam was influenced by different additive substances. The results showed that highest enrichment values were obtained from ß-lactoglobulin as much as 368.3 times. The lowest enrichment values (5.9 times) were determined for the application without additive. After enrichment, each experiment of glycyrrhizic acid ammonium salt confirmed that these substances could be quantitatively enriched into the collection vessel with isoelectric focused adsorptive bubble separation technique. The transfer of glycyrrhizic acid ammonium salt into the foam from standard solution in the presence of additive was more efficient than aqueous licorice extract.

3.
Appl Biochem Biotechnol ; 170(7): 1589-601, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23709288

ABSTRACT

Foam fractionation is a promising method for separation and concentration of biochemicals. It is simple, easily scalable, inexpensive, and environment friendly. Foam fractionation thus represents an alternative to the traditional methods used for immunoglobulin enrichment. However, little, if any, literature exists documenting the utilization of foam fractionation in the enrichment of immunoglobulins. Milk were utilized as an immunoglobulin source to serve as examples of a real system in this study. The investigation examined the effects of varying five different process parameters: the initial pH value, the initial concentration of immunoglobulin, the nitrogen flow rate, the column height, and the foaming time. Experimental results demonstrated that immunoglobulin could effectively be enriched from milk by foam fractionation. The maximum enrichment ratio with pretreatment (using pH 4.6 precipitation) was 6.30 along with a more than 92 % recovery for IgG and an enrichment ratio of 5.1 with 85 % recovery for IgM.


Subject(s)
Chemical Fractionation/methods , Immunoglobulin G/isolation & purification , Immunoglobulin M/isolation & purification , Milk/chemistry , Models, Chemical , Nitrogen/chemistry , Animals , Cattle , Computer Simulation , Gases/chemistry , Hydrogen-Ion Concentration , Immunoglobulin G/chemistry , Immunoglobulin M/chemistry
4.
J Pharm Biomed Anal ; 75: 220-9, 2013 Mar 05.
Article in English | MEDLINE | ID: mdl-23277154

ABSTRACT

Butterbur (Petasites) is an ancient plant which has been used for medical and edible purposes with its spasmolytic agents. However, toxic alkaloid content of the plant limits its direct usage. The paper covers the pyrrolizidine alkaloids (PAs) and butterbur themes in detail in order to display the outline of alkaloid-free plant extract production for medical and edible purposes. The toxic PAs and medicinal constituents of the plant are described with emphasis on analytics, physiological effects and published patent data on alkaloid free extract production. The analytics is based on several commonly used analytical methods including liquid chromatography-mass spectrometry, gas chromatography-mass spectrometry and enzyme linked immunoassay analysis of PAs and N-oxides based on published literature data of butterbur. The analyses of major medicinal constituents of butterbur are given and the physiological effects of these compounds have been discussed to attract attention to the importance of alkaloid-free extract production. The concentration distributions of the medicinal constituents and toxic PAs in different parts of the plant and the outcomes of the published patent data provide comprehensive information for proper plant raw-material selection and production of alkaloid-free butterbur extracts. The review is intended to guide researchers interested in medical plant extracts by providing comprehensive data on the medical plant butterbur and its chemical constituents.


Subject(s)
Carcinogens/analysis , Dietary Supplements , Petasites/chemistry , Plant Extracts/chemistry , Pyrrolizidine Alkaloids/analysis , Analgesics, Non-Narcotic/analysis , Analgesics, Non-Narcotic/chemistry , Analgesics, Non-Narcotic/isolation & purification , Analgesics, Non-Narcotic/therapeutic use , Animals , Anti-Inflammatory Agents, Non-Steroidal/analysis , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/isolation & purification , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Carcinogens/metabolism , Carcinogens/toxicity , Chemical and Drug Induced Liver Injury/prevention & control , Ethnopharmacology , Humans , Parasympatholytics/analysis , Parasympatholytics/chemistry , Parasympatholytics/isolation & purification , Parasympatholytics/therapeutic use , Petasites/growth & development , Petasites/metabolism , Phytotherapy , Plant Extracts/isolation & purification , Plant Leaves/chemistry , Plant Leaves/growth & development , Plant Leaves/metabolism , Pyrrolizidine Alkaloids/metabolism , Pyrrolizidine Alkaloids/toxicity , Rhizome/chemistry , Rhizome/growth & development , Rhizome/metabolism , Sesquiterpenes/analysis , Sesquiterpenes/metabolism , Sesquiterpenes/therapeutic use , Stereoisomerism
5.
J Environ Sci Health B ; 45(7): 666-75, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20818520

ABSTRACT

Cobalt and silver are toxic for cells, but mechanisms of this toxicity are largely unknown. Analysis of Corynebacterium glutamicum proteome from cells grown in control and cobalt or silver enriched media was performed by two dimensional gel electrophoresis (2DE) followed by mass spectrometry. Our results indicate that the cell adapted to cobalt stress by inducing five defense mechanisms: Scavenging of free radicals, promotion of the generation of energy, reparation of DNA, reparation and biogenesis of Fe-S cluster proteins and supporting and reparation of cell wall. In response to the detoxification of Ag+ many proteins were up-regulated, which involved reparation of damaged DNA, minimizing the toxic effect of reactive oxygen species (ROS) and energy generation. Overexpression of proteins involved in cell wall biosynthesis (1,4-alpha-glucan branching enzyme and nucleoside-diphosphate-sugar epimerase) upon cobalt stress and induction of proteins involved in energy metabolism (2-methylcitrate dehydratase and 1, 2-methylcitrate synthase) upon silver demonstrate the potential of these enzymes as biomarkers of sub-lethal Ag+ and Co toxicity.


Subject(s)
Cobalt/pharmacology , Corynebacterium glutamicum/drug effects , Corynebacterium glutamicum/physiology , Environmental Monitoring/methods , Proteome/metabolism , Silver/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Corynebacterium glutamicum/chemistry , Corynebacterium glutamicum/genetics , Gene Expression Regulation, Bacterial/drug effects , Proteome/chemistry , Proteome/genetics , Stress, Physiological/drug effects
6.
Appl Biochem Biotechnol ; 162(6): 1547-57, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20229282

ABSTRACT

Tweezing adsorptive bubble separation (TABS) was used as a method for the enrichment of matrix metalloproteinases (92-kDa type IV, gelatinase B (MMP-9)) and carboxypeptidase A (CPA) from dilute aqueous solutions. The method is based on the chelation of metalloenzymes applying 2-(carbamoylmethyl-(carboxymethyl)amino)acetic acid (ADA) coupled with an octyl part to form a surface active unit. MMP-9 could be enriched with an enrichment ratio of 12.0 and a recovery of 87.3%, and CPA could be enriched 18.8-fold and with 95.3% recovery. Both enzymes were enriched without significant losses of enzymatic activity. To verify that the enzymes were tweezed by ADA-C8 without abstraction of the zinc ions from the active center, TABS trials were additionally conducted with zinc ions in complex with ADA-C8, which revealed only negligible enrichment ratios of the enzymes (2.2 for MMP-9 and 0.2 for CPA). The results obtained impressively demonstrate that zinc-containing proteases can be enriched selectively and efficiently by TABS.


Subject(s)
Carboxypeptidases A/isolation & purification , Chemistry Techniques, Analytical/methods , Matrix Metalloproteinase 9/isolation & purification , Carboxypeptidases A/analysis , Matrix Metalloproteinase 9/analysis
7.
Environ Int ; 35(8): 1125-35, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19664822

ABSTRACT

Polybrominated diphenyl ethers (PBDE) are used as flame retardants in a wide variety of products. As part of the Integrated Exposure Assessment Survey (INES), this study aimed to characterize the exposure of an adult German population using duplicate diet samples, which were collected daily over seven consecutive days, and indoor air and house dust measurements. Our study population consisted of 27 female and 23 male healthy subjects, aged 14-60 years, all of whom resided in 34 homes in southern Bavaria. In these 34 residences the air was sampled using glass fiber filters and polyurethane foams and the dust was collected from used vacuum cleaner bags. The median (95th percentile) daily dietary intake of six Tetra- to HeptaBDE congeners was 1.2 ng/kg b.w. (3.3 ng/kg b.w.) or 67.8 ng/day (208 ng/day) (calculated from the 7-day median values of each study subject). Concentrations in indoor air and dust (cumulative Tri- to DecaBDE congener readings) ranged from 8.2 to 477 pg/m(3) (median: 37.8 pg/m(3)) and 36.6 to 1580 ng/g (median: 386 ng/g), respectively. For some congeners, we identified a significant correlation between air and dust levels. The median (95th percentile) blood concentration of total Tetra- to HexaBDE congener readings was 5.6 (13.2)ng/g lipid. No significant sex differences were observed, but higher blood concentrations were found in younger participants. Using a simplified toxicokinetic model to predict the body burden from exposure doses led to results that were of the same order of magnitude as the measured blood concentrations. Based on these measurements and given our exposure assumptions, we estimated for the total tetra- to heptabrominated congener count an average (high) comprehensive total daily intake of 1.2 ng/kg b.w. (2.5 ng/kg b.w.). Overall, our results suggest that dietary exposure is the dominant intake pathway at least in our study population, responsible for 97% (average intake) and 95% (high intake) of the total intake of an adult population.


Subject(s)
Air Pollutants/analysis , Air Pollution, Indoor/analysis , Dust/analysis , Environmental Exposure/analysis , Flame Retardants/analysis , Halogenated Diphenyl Ethers/analysis , Adolescent , Adult , Air Pollutants/blood , Body Burden , Diet , Environmental Monitoring , Female , Food Analysis , Germany , Halogenated Diphenyl Ethers/blood , Humans , Male , Middle Aged , Young Adult
8.
J Agric Food Chem ; 57(2): 341-7, 2009 Jan 28.
Article in English | MEDLINE | ID: mdl-19113873

ABSTRACT

Bark from Pinus brutia was extracted with supercritical fluid extraction (SFE), using CO(2), at various extraction conditions both at laboratory and at pilot scale. Optimized parameters were 200 bar, 60 degrees C, and 3% ethanol at a solvent/feed ratio of 30. Additionally, the pine bark was sonicated (1 h at 50 degrees C) by different solvents (n-hexane, dichloromethane, ethyl acetate, and ethanol) to investigate the correlation between the different extraction setups and to obtain information on SFE up-scaling possibilities. Analyzed by HPLC, 7.2% of (-)-catechin was extractable at laboratory scale, and 58.4% (800 bar) and 47.8% (200 bar), both with modifiers, at pilot scale. By sonication with ethanol, 46.8% of (-)-catechin and almost 100% of (-)-epicatechin and (-)-catechin gallate were extracted. Ethyl acetate extract revealed high correlations with the laboratory scale SFE (r = 0.98) and also pilot scale SFE runs at 200 (r = 0.99) and 800 bar (r = 0.98) without modifiers.


Subject(s)
Chromatography, Supercritical Fluid/methods , Organic Chemicals/chemistry , Pinus/chemistry , Plant Bark/chemistry , Solvents/chemistry , Acetates , Carbon Dioxide/chemistry , Chromatography, High Pressure Liquid , Plant Extracts/chemistry
9.
Proteomics ; 8(23-24): 4976-86, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18972541

ABSTRACT

Cadmium and mercury are well-known toxic heavy metals, but the basis of their toxicity is not well understood. In this study, we analyzed the cellular response of Corynebacterium glutamicum to sublethal concentrations of cadmium and mercury ions using 2-DE and MS. Mercury induced the over-expression of 13 C. glutamicum proteins, whereas 35 proteins were induced, and 8 proteins were repressed, respectively, under cadmium stress. The principal response to these metals was protection against oxidative stress, as demonstrated by upregulation of, e.g., Mn/Zn superoxide dismutase. Thioredoxin and oxidoreductase responded most strongly to cadmium and mercury. The increased level of heat-shock proteins, enzymes involved in energy metabolism, as well as in lipoic acid and terpenoid biosynthesis after the treatment of cells with cadmium was also registered. Identification of these proteins and their mapping into specific cellular processes enable a global understanding of the way in which C. glutamicum adapts to heavy-metal stress and may help to gain deeper insight into the toxic mechanism of these metals.


Subject(s)
Cadmium/toxicity , Corynebacterium glutamicum/drug effects , Mercury/toxicity , Proteome/analysis , Bacterial Proteins/analysis , Corynebacterium glutamicum/cytology , Corynebacterium glutamicum/growth & development , Electrophoresis, Gel, Two-Dimensional
10.
J Sep Sci ; 31(12): 2310-7, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18615831

ABSTRACT

Alkyl-substituted insulin molecules are depository preparations used in the treatment of diabetes. The isolation and purification of these active compounds is performed on the hand of several complicated separation steps. In this work, nonmodified and new synthesized alpha,beta-unsaturated bovine insulins-(C12)(n) were selectively isolated from aqueous solution using tweezing adsorptive bubble separation (TABS) with BSA, which enabled reversible binding with the unpolar side chains of bovine insulin and its derivates. The bovine insulin/serum albumin complex could be efficiently transferred into the foam phase at pH 8 with an enrichment factor of 2.6 and a recovery of 89.7%. Experiments with alkylated alpha,beta-unsaturated bovine insulins-(C12)(n) performed at pH 9 enriched even quantitatively the complex under equal experimental conditions, accompanied with an enrichment factor of 3.3. Additionally performed radio immunoassay tests revealed that the immunological activity of alpha,beta-unsaturated bovine insulins-(C12)(n) remained unchanged after foaming.


Subject(s)
Chemistry Techniques, Analytical/methods , Insulin/chemistry , Insulin/isolation & purification , Adsorption , Alkylation , Animals , Cattle , Chemistry Techniques, Analytical/instrumentation , Equipment Design , Hydrogen-Ion Concentration , Insulin/chemical synthesis , Insulin/immunology , Luminescent Measurements , Molecular Structure , Serum Albumin, Bovine/isolation & purification
11.
Food Chem Toxicol ; 46(7): 2320-5, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18433970

ABSTRACT

Toxaphene is a chlorinated pesticide consisting of more than 200 congeners that are mainly chlorobornanes and chlorocamphenes. As the congeners exhibit different stability properties in the environment, only between 20 and 30 compounds can be observed in, e.g., fish, which are represented by technical toxaphene as a mixture. In human body, the congeners Parlar #26, #40, #41, #44, #50, and #62 are detected frequently. Three of them, #26, #50, and #62, pose a potential risk to human health due to their persistent characteristic. By using experimental results of a European Union study (MATT, 2000. Investigation into the Monitoring, Analysis and Toxicity of Toxaphene in Marine Foodstuffs, European Union, Brussels, Final report, FAIR CT PL.96.3131. Investigation into the Monitoring, Analysis and Toxicity of Toxaphene in Marine Foodstuffs), a reference dose related to tumor promotion was calculated for these representative persistent toxaphene congeners. In Germany, the sum of the congeners #26, #50, and #62 is defined as the official standard for toxaphene residues in food. In this work, different fish samples obtained from German markets were studied regarding their contamination with toxaphene congeners, presented either in sum, or as single constitutes. The obtained data were used to define the acceptable total concentration of the sum of Parlar #26, #50, and #62 with regard to prevention of tumor promotion in human. The results showed that the currently existing permissible level of the sum of these congeners (0.1 mg/kg) is higher than the acceptable concentration in fish samples determined by this work and calculated at ca. 0.090 mg/kg. It is therefore recommended to improve the permissible level of toxaphene in German food samples.


Subject(s)
Carcinogens/analysis , Food Contamination/analysis , Insecticides/analysis , Seafood/analysis , Toxaphene/analysis , Animals , Carcinogens/toxicity , Fishes/metabolism , Germany , Humans , No-Observed-Adverse-Effect Level , Pesticide Residues/analysis , Risk Assessment , Toxaphene/analogs & derivatives , Toxaphene/toxicity
12.
Chemosphere ; 72(1): 87-94, 2008 May.
Article in English | MEDLINE | ID: mdl-18328530

ABSTRACT

The aim of this study was to determine a new spectrum of substances that will be selected for future breast milk monitoring in Bavaria, Germany. Up to now, the analysis of breast milk in Bavaria was limited to selected organochlorine pesticides (OCP) and polychlorinated biphenyls (PCB). Information on background levels of toxicologically interesting substances, such as dioxins and dioxin-like polychlorinated biphenyls (dl-PCB) or on flame retardants, such as polybrominated diphenyl ethers (PBDE) are very limited or not available for Bavaria. We present here levels on OCP, some nitro musks, indicator PCB, polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and dl-PCB concentrations in breast milk collected at 12 weeks post-partum of 43 primiparous mothers living in Bavaria. The average concentrations of PCDD, PCDF and dl-PCB were 4.98, 4.93 and 9.92 pg WHO-TEQ g(-1) lipid, respectively. The mean contribution of PCDD, PCDF, non-ortho and mono-ortho PCB to the total WHO-TEQ is consistently about 25% each. Furthermore the concentration on PBDE in breast milk at two sampling points, 12 weeks and 16 weeks after delivery, were determined. Overall, 19 PBDE congeners were analysed, however the level of 12 PBDE congeners were below the limit of detection. BDE-153 and BDE-47 were the predominant congeners accounting for about 66% of the total PBDE. The means of the total concentrations of PBDE (five congeners) at the first and second sampling point were 1.90 and 2.03 ng g(-1) lipid, respectively. Based on our results the overall concentrations of the analysed substances in milk samples from Bavaria are consistent with the levels of breast milk samples of other European countries reflecting the low background body burden of these compounds.


Subject(s)
Fatty Acids, Monounsaturated/analysis , Hydrocarbons, Chlorinated/analysis , Milk, Human/chemistry , Polybrominated Biphenyls/analysis , Environmental Exposure , Ethers , Germany , Humans
13.
Chemosphere ; 69(1): 25-31, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17568655

ABSTRACT

The herbicide 2,4-dichlorophenoxy acetic acid (2,4-D) induces a wide spectrum of toxic responses in living organisms. In this study, we analyzed the stress-induced responses of Corynebacterium glutamicum cells on protein level upon treatment with 2,4-D. For this, growing C. glutamicum cells were exposed to sublethal concentrations of 2,4-D, and changes of the gene expression profiles in comparison to non-exposed organisms were analyzed by two-dimensional gel electrophoresis and mass spectrometry. 2,4-D induced the over-expression of at least six C. glutamicum proteins, four of which could be identified by MALDI-TOF-MS. One protein (Cg2521; long-chain acyl-CoA synthetase) was related to the energy metabolism, and two proteins were involved in cell envelope synthesis (Cg2410; glutamine-dependent amidotransferase, and Cg1672; glycosyltransferase). The last induced protein was the ABC type transport system (Cg2695, ATPase component). The newly observed proteins, except for the ABC transport system, were not in general stress-related proteins, but were specifically expressed upon 2,4-D exposure and, therefore, can be used as respective biomarkers. Moreover, since these proteins seem to play a pivotal role in the adaptation of the cell to 2,4-D, they may help to gain deeper insight into the damage mechanisms of 2,4-D induced in the living cell.


Subject(s)
2,4-Dichlorophenoxyacetic Acid/toxicity , Bacterial Proteins/metabolism , Corynebacterium glutamicum/drug effects , Herbicides/toxicity , Adaptation, Physiological , Corynebacterium glutamicum/growth & development , Corynebacterium glutamicum/metabolism , Proteome
14.
Anal Chem ; 77(19): 6113-7, 2005 Oct 01.
Article in English | MEDLINE | ID: mdl-16194067

ABSTRACT

A novelly developed tweezing-adsorptive bubble separation (ABS) method for the enrichment of metalloenzymes (laccase C and horseradish peroxidase) is introduced. The method is based on the chelation of the enzymes' active center and can also be applied for analysis. N-(2-acetamido)iminodiacetic acid served as a chelator and was synthesized with an octyl unit to become ADA-C8. Laccase was enriched 13.3-fold (66.31% recovery) and HPOX 17.8-fold (85.34%) without a significant loss of enzymatic activity. To prove that the entire enzyme is tweezed at the active center, ABS trials were done using ADA-C8 already complexed with Cu2+ and Fe3+. As only marginal enrichment occurred (ER laccase, 0.17; ER HPOX, 0.44), no chelating effect was concluded. It was determined how the chelation toward the active center was directed by applying other chelators such as EDTA, NTA, N,N-dimethylaminoglycine, oxalic acid, malonic acid, adipinic acid, and tripropylamine, which are similar in structure to ADA-C8. The results concluded that the chelation is 3-fold coordinated on the type 1 copper center of laccase, whereas that of HPOX only 1-fold at Fe3+ and additionally at the cationic amino acid arginine, which is also located at the active center. Tweezing-ABS has been proven to selectively and effectively enrich metalloenzymes.


Subject(s)
Horseradish Peroxidase/isolation & purification , Laccase/isolation & purification , Metalloproteins/isolation & purification , Absorption , Binding Sites , Chelating Agents/chemistry , Chelating Agents/metabolism , Horseradish Peroxidase/chemistry , Horseradish Peroxidase/metabolism , Laccase/chemistry , Laccase/metabolism , Metalloproteins/metabolism , Models, Molecular , Protein Structure, Tertiary
15.
J Nat Prod ; 68(9): 1386-9, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16180819

ABSTRACT

Biologically active compounds from several useful plants were enriched using foam fractionation, a separatory method belonging to the adsorptive bubble separation (ABS). Nonpolar humulones (1-6) from Pilsener beer, curcuminoids (7-9) from turmeric, and carotenoids (16 and 17) from carrot juice were enriched fast and quantitatively, depending on the process parameters, whereas more polar compounds such as catechins from green tea (11, 12, 14, and 15) and naringin (18) and hesperidin (19) from orange and grapefruit juices could not be enriched.


Subject(s)
Chemical Fractionation/methods , Plant Extracts/analysis , Carotenoids/analysis , Chromatography, High Pressure Liquid , Citrus/chemistry , Curcuma/chemistry , Curcumin/analogs & derivatives , Curcumin/analysis , Cyclohexenes , Daucus carota/chemistry , Flavanones/analysis , Hesperidin/analysis , Molecular Structure , Tea/chemistry , Terpenes/analysis , Water/chemistry
16.
J Agric Food Chem ; 53(18): 7156-64, 2005 Sep 07.
Article in English | MEDLINE | ID: mdl-16131124

ABSTRACT

A total of 22 chiral toxaphene congeners were analyzed in organ tissues and eggs of laying hens after they had been fed with food spiked with technical toxaphene. For the analysis, multidimensional high-resolution gas chromatography using a chiral column coated with randomly silylated heptakis(O-tert-butyldimethylsilyl)-beta-cyclodextrin, electron capture detection, and valveless "live column switching" technique was applied. The analytical results were additionally confirmed with mass spectral data, recorded in electron-capture negative ionization mode with selected-ion monitoring mass spectrometry. During both the feeding period of the laying hens with toxaphene-contaminated food (38 weeks, accumulation phase) and the following subsiding period without toxaphenes (another 14 weeks, decontamination phase), organs (liver, kidney, skin/fat), blood, meat, and eggs of the hens served as model matrices for toxaphene uptake. The enantiomeric ratios (ERs) of congeners 26, 31, 32, 40, 41, 42(a+b), 44, 50, and 62--known as the most important components of technical toxaphene occurring in the environment--could be analytically determined. Significant differences were observed with respect to their initial racemic ratios. On the basis of their chemical structures, the metabolic pathways of some congeners could be explained. Astonishingly, some of the toxaphenes applied as racemates could merely be found as single enantiomers at the end of the feeding program, for example, congener 32 in blood and meat samples or congener 44, especially in organ tissues, which showed ERs of zero or infinity. The findings of this study impressively emphasize that it is essential to isolate and analyze individual toxaphene enantiomers in food and biota tissues to be capable of evaluating their toxicity and metabolization more specifically.


Subject(s)
Chickens , Chromatography, Gas/methods , Eggs/analysis , Insecticides/chemistry , Toxaphene/chemistry , Animal Feed , Animals , Female , Food Contamination/analysis , Meat/analysis , Oviposition , Stereoisomerism , Toxaphene/administration & dosage
17.
Int J Food Sci Nutr ; 56(3): 223-9, 2005 May.
Article in English | MEDLINE | ID: mdl-16009637

ABSTRACT

The feasibility of foam fractionation, as an alternative to other more commonly used methods, to effectively separate total whey proteins and single fractions has been studied. The investigation focused on the effects of different process parameters such as the pH value, the initial protein concentration, the flow rate and the addition of sodium dodecyl sulfate concentration as a surfactant. Whey proteins could be almost completely enriched into the foam fraction at pH values between 2 and 3; only traces of them remained in the residual whey solution. Albumin bovine, beta-lactoglobulin and alpha-lactalbumin from whey solutions in the presence of sodium dodecyl sulfate could be transferred into the foam fraction with enrichment ratios of up to 30 and with recovery rates between 64.5% and 99.8%. The results demonstrate that enriching whey proteins using foam fractionation can be quantitative and effective according to process parameters.


Subject(s)
Food Handling/methods , Milk Proteins/isolation & purification , Chemical Fractionation/methods , Hydrogen-Ion Concentration , Lactalbumin/isolation & purification , Lactoglobulins/isolation & purification , Sodium Dodecyl Sulfate , Surface-Active Agents , Whey Proteins
18.
Lipids ; 40(3): 323-7, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15957260

ABSTRACT

Active lipases were isolated from the culture supernatant of the basidiomycetous fungus Pleurotus sapidus by foam fractionation. The pH value, the gas flow, and the foaming period were systematically varied to optimize the transport of the enzymes into the foam phase. On a 70-mL scale, a maximum recovery of hydrolytic activity of 95% was obtained at pH 7.0 and 60 mL N2 min(-1) after 50 min. The procedure, with minor modifications, was also applicable to native pellet cultures of P. sapidus. The same recovery of 95% was achieved, with purification and enrichment factors of 11.6 and 28.0, respectively.


Subject(s)
Lipase/metabolism , Pleurotus/enzymology , Extracellular Space/enzymology , Fungal Proteins/isolation & purification , Fungal Proteins/metabolism , Kinetics , Lipase/isolation & purification
19.
Environ Sci Technol ; 39(6): 1736-40, 2005 Mar 15.
Article in English | MEDLINE | ID: mdl-15819232

ABSTRACT

The irradiation of 2,2,3-exo,5-endo,6-exo,8,9,9,10,10-decachlorobornane in n-hexane at 254 nm leads to a spontaneous Cl2 elimination as the major reaction pathway. This results finally in the main product 2,5-endo,6-exo,8,9,9,10,10-octachlorobornene-2, of which the structure could be elucidated with the help of X-ray, 1H and 13C NMR, IR, and MS. Temperature-dependent 1H NMR spectroscopic investigations have shown that the -CHCl2 groups located at C1 and C7 are able to rotate slowly under normal circumstances. If such measurements, however, are exerted at low temperatures (-10 to -60 degrees C), so can be seen that two rotamers are formed due to the hindrance of the free rotation about the bonds C1-C10, C7-C8, and C7-C9, which for the first time could be revealed for a toxaphene compound. Furthermore, as all 1H NMR chlorobornane spectra known so far show only sharp and clear signals, it can be assumed that chlorobornane compounds as main toxaphene components have fixed bonds, which requires to indicate chlorine atoms within the tentacles such as "a", "b", and "c" for characterizing the correct position. Those fixed tentacles are probably the reason that many toxaphene congeners remain very stable in environmental compartments, and particularly the biotic and abiotic transformation may strongly be hindered by the inflexibility of the tentacles.


Subject(s)
Bridged Bicyclo Compounds/chemistry , Insecticides/chemistry , Toxaphene/chemistry , Isomerism , Magnetic Resonance Spectroscopy , Molecular Structure , Temperature
20.
Chemosphere ; 58(3): 253-62, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15581928

ABSTRACT

Top layer sediment samples from the Czech Republic were analyzed to obtain the preliminary information about contamination of the region by chlorinated paraffins. Sediment samples from three locations with different industrial discharges were taken over the period of 2 years. The analysis was performed by short-column gas chromatography-electron capture negative ion mass spectrometry (SCGC/ECNI-MS). Short chain chlorinated paraffin sediment concentrations varied between 24.00 and 45.78 ng g(-1) (dry weight, d.w.) in the Kosetice area, 16.30-180.75 ng g(-1) (dry weight) in the Zlín area and 4.58-21.57 ng g(-1) dry weight in the Beroun area. Highly chlorinated undecanes prevailed in the samples. On the basis of these results, more detailed studies should be conducted to determine the magnitude and extent of chlorinated paraffin contamination in these regions.


Subject(s)
Paraffin/analysis , Soil Pollutants/analysis , Czech Republic , Environmental Monitoring , Gas Chromatography-Mass Spectrometry , Geologic Sediments/chemistry , Paraffin/chemistry
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