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1.
J Sci Food Agric ; 100(3): 926-935, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31523827

RESUMO

BACKGROUND: The effects were studied of different inoculation strategies for selected starters -yeasts and lactic acid bacteria (LAB) - used for the fermentation process of two Greek olive cultivars, Conservolea and Kalamàta. The LAB strains applied were Leuconostoc mesenteroides K T5-1 and L. plantarum A 135-5; the selected yeast strains were S. cerevisiae KI 30-16 and Debaryomyces hansenii A 15-44 for Kalamàta and Conservolea olives, respectively. RESULTS: Table olive fermentation processes were monitored by performing microbiological analyses, and by monitoring changes in pH, titratable acidity and salinity, sugar consumption, and the evolution of volatile compounds. Structural modifications occurring in phenolic compounds of brine were investigated during the fermentation using liquid chromatography / diode array detection / electrospray ion trap tandem mass spectrometry (LC/DAD/ESI-MSn ) and quantified by high-performance liquid chromatography (HPLC) using a diode array detector. Phenolic compounds in processed Kalamàta olive brines consisted of phenolic acids, verbascoside, caffeoyl-6-secologanoside, comselogoside, and the dialdehydic form of decarboxymethylelenolic acid linked to hydroxytyrosol, whereas oleoside and oleoside 11-methyl ester were identified only in Conservolea olive brines. CONCLUSION: Volatile profile and sensory evaluation revealed that the 'MIX' (co-inoculum of yeast and LAB strain) inoculation strategy led to the most aromatic and acceptable Kalamàta olives. For the Conservolea table olives, the 'YL' treatment gave the most aromatic and the overall most acceptable product. © 2019 Society of Chemical Industry.


Assuntos
Debaromyces/metabolismo , Microbiologia de Alimentos/métodos , Lactobacillales/metabolismo , Olea/química , Olea/microbiologia , Fenol/metabolismo , Saccharomyces cerevisiae/metabolismo , Fermentação , Frutas/química , Frutas/microbiologia , Humanos , Fenol/análise , Sais/análise , Sais/metabolismo , Paladar
2.
Chemosphere ; 239: 124696, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31726529

RESUMO

Brine disposal is a major drawback for seawater desalination. Membrane distillation (MD) is an emerging technology to treat a high saline water including brine disposal instead of reverse osmosis, multi-stage flash and multi-effect distillation. This study investigated a pilot scale of a spiral-wound air gap MD (AGMD) module and evaluated its efficiency. A pilot-scale AGMD module with design production capacity of 10 m3/d was operated. Experiments with varying flow velocity showed increasing trend of water vapor flux as flow velocity increases. The temperature is one of the significant points in maximizing water permeate vapor flux in MD. Increasing temperature from 65 °C to 75 °C in evaporator channel has increased flux from 0.59 to 1.15 L/m2/h. Under various conditions, specific thermal energy consumption (STEC) and gained output ratio (GOR) was used to analyze energy efficiency. The pilot plant showed high GOR value in spite of a limited heating and cooling source available at the site. The highest GOR achieved was 3.54 with STEC of 182.78 kWh/m3. This study provides an overview of operation experience and its data analysis related to temperature, concentration, flow rate and energy supply.


Assuntos
Destilação/métodos , Membranas Artificiais , Sais/análise , Purificação da Água/métodos , Destilação/instrumentação , Temperatura Alta , Osmose , Projetos Piloto , Água do Mar/química , Água/química
3.
Environ Monit Assess ; 192(1): 12, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811443

RESUMO

A decline in surface water sources in Pakistan is continuously causing the over-extraction of groundwater resources which is in turn costing the saltwater intrusion in many areas of the country. The saltwater intrusion is a major problem in sustainable groundwater development. The application of electrical resistivity methods is one of the best known geophysical approaches in groundwater study. Considering the accuracy in extraction of freshwater resources, the use of resistivity methods is highly successful to delineate the fresh-saline aquifer boundary. An integrated geophysical study of VES and ERI methods was carried out through the analysis and interpretation of resistivity data using Schlumberger array. The main purpose of this investigation was to delineate the fresh/saline aquifer zones for exploitation and management of fresh water resources in the Upper Bari Doab, northeast Punjab, Pakistan. The results suggest that sudden drop in resistivity values caused by the solute salts indicates the saline aquifer, whereas high resistivity values above a specific range reveal the fresh water. However, the overlapping of fresh/saline aquifers caused by the formation resistivity was delineated through confident solutions of the D-Z parameters computed from the VES data. A four-layered unified model of the subsurface geologic formation was constrained by the calibration between formation resistivity and borehole lithologs. i.e., sand and gravel-sand containing fresh water, clay-sand with brackish water, and clay having saline water. The aquifer yield contained within the fresh/saline aquifers was measured by the hydraulic parameters. The fresh-saline interface demarcated by the resistivity methods was confirmed by the geochemical method and the local hydrogeological data. The proposed geophysical approach can delineate the fresh-saline boundary with 90% confidence in any homogeneous or heterogeneous aquifer system.


Assuntos
Monitoramento Ambiental/métodos , Geologia/métodos , Água Subterrânea/análise , Água Doce/análise , Água Subterrânea/normas , Paquistão , Sais/análise , Recursos Hídricos
4.
Environ Sci Pollut Res Int ; 26(14): 14171-14177, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30859441

RESUMO

The preparation of coal water slurry (CWS) using wastewater, which contains inorganic and organic components, is one method of wastewater utilization. In this study, the effect of inorganic salts on the viscosity of CWS was examined. The results show that monovalent salts (NaCl, KCl) decreased the viscosity of CWS. The viscosity of CWS was not affected by bivalent salts (CaCl2, MgCl2). However, CWS combined with trivalent salt (AlCl3) sharply increased the viscosity. The zeta potential of CWS with inorganic salts increased which can enhance the electric repulsion and beneficial to reduce the viscosity. The content of free water in CWS with trivalent salt decreased, and the freedom of the free water in CWS with trivalent salt decreased which were all bad to the viscosity and the adsorption of the dispersant on the particles. Compared with the surface polarity of the particles without inorganic salts, the surface polarity of the particles with divalent salts was similar to those without inorganic salts. Under the comprehensive influence, divalent salt has little effect on the viscosity of CWS.


Assuntos
Sais/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Adsorção , Carvão Mineral/análise , Cloreto de Potássio/análise , Cloreto de Sódio/análise , Viscosidade , Água
5.
Chemosphere ; 224: 487-493, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30831500

RESUMO

Tetracyclines belong to the group of the most applied antibiotics in veterinary medicine worldwide. Due to their incomplete absorption and/or metabolism in the animal gut, tetracyclines are frequently detected in manure samples. Within the matrix, an elimination of these compounds has been reported in several studies. However, only little information about potential transformation products of tetracyclines in manure and the environment is available. Therefore, the fate of tetracycline (TC) and chlortetracycline (CTC) was investigated in aqueous solutions and manure. Abiotic incubation of TC in phosphate buffer led to a remarkable red-brown coloring of the solution. Subsequent compound isolation and structure elucidation by MS/MS and NMR techniques revealed the formation of seco-cycline A, a compound formerly described as a fungal biotransformation product of TC. For CTC, two comparable products were identified which were derived from its isomeric form isoCTC. All transformation products showed no antimicrobial activity for concentrations up to 500 mg L-1. When TC and CTC were incubated in cow manure for 7 d, the above mentioned three transformation products were also formed in this complex matrix (up to 5.1 mg kg-1). Manure, soil and leachate samples from Lower Saxony revealed the presence of seco-cycline A in manure and soil, but not in water. To obtain a better insight in the fate of tetracyclines in environmental matrices, future analytical and ecotoxicological studies dealing with this subject should include the analysis especially of seco-cycline A.


Assuntos
Antibacterianos/metabolismo , Bactérias/efeitos dos fármacos , Clortetraciclina/metabolismo , Esterco/análise , Sais/análise , Tetraciclina/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Antibacterianos/análise , Bovinos , Clortetraciclina/análise , Solo/química , Tetraciclina/análise , Poluentes Químicos da Água/análise
6.
Isotopes Environ Health Stud ; 55(1): 41-55, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30618268

RESUMO

The routine methods for stable oxygen and hydrogen isotope analysis of water involve water-CO2 gas equilibration and water reduction on hot metal (e.g. Zn, Cr, U) and subsequent mass spectrometric analysis of the evolved gases of CO2 and H2 for 18O/16O and 2H/1H ratios, respectively. Precise determination of the isotopic composition of water in brines with application of these standard methods is still problematic and technically often impossible due to detrimental influence of dissolved salts. The new method of brine desalination presented in this study overcomes the problem of the isotope salt effects encountered during the application of the routine techniques for the determination of the isotopic composition of high saline waters. The procedure combines two technical steps: (i) the chemical precipitation of Mg and Ca ions as insoluble non-hydroscopic fluorides, and (ii) the vacuum distillation of water from solution-precipitate mixture. The application of simple vacuum distillation allows full extraction of water and dehydration of remaining salts in a temperature range from 300 to 350 °C without hydrogen and oxygen isotope fractionation. The precision and accuracy of δ18O and δ2H determination of saline waters and brines with prior application of AgF desalination procedure is comparable with that usually obtained for fresh waters.


Assuntos
Deutério/análise , Fluoretos/química , Isótopos de Oxigênio/análise , Sais/análise , Água do Mar/análise , Compostos de Prata/química , Purificação da Água/métodos , Cálcio/química , Precipitação Química , Magnésio/química , Salinidade
7.
Se Pu ; 37(2): 227-232, 2019 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-30693733

RESUMO

A method for the determination of propionic acid and its salts in food by gas chromatography (GC) was developed. Degrease extraction and direct extraction were established for food containing oil and non-oil, respectively. In this study, the effects of different pH values on the solubility and recovery of propionic acid were investigated. The effects of purification conditions, pH values, extraction agent types, and extraction times were studied. After hydrochloric acid solution was added, the pH levels of sample solutions were all found to be less than 2. The sample solutions were degreased with 5 mL n-hexane and extracted twice with 5 mL ethyl acetate. The analytes were detected by GC. The analytes were separated on an HP-INNOWAX chromatographic column and detected by fame ionization detector (FID). The recoveries of degrease extraction were 87.5%-97.6% and relative standard deviation were 3.09%-6.86% (n=6). The recoveries of direct extraction were 90.1%-102.1% and the relative standard deviations were 3.32%-6.33% (n=6). The two methods showed good linearities in the range of 2-1000 mg/L (correlation coefficient is 0.9998). The limit of detection was 0.003 g/kg and the limit of quantification was 0.01 g/kg. The proposed method is accurate, fast, simple, easy, sensitive, and is suitable for the rapid determination of propionic acid and its salts in different food. The proposed method provides a new way for the determination of propionic acid in food.


Assuntos
Análise de Alimentos , Propionatos/análise , Sais/análise , Cromatografia Gasosa
8.
J Food Sci ; 84(1): 121-126, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30548261

RESUMO

Staphylococcus aureus food poisoning, which is still a serious health problem worldwide, is caused by the intoxication of staphylococcal enterotoxin (SE). Among many types of SE, staphylococcal enterotoxin type A (SEA) is known to be the most responsible for S. aureus food poisoning worldwide. Several researchers have reported the modeling of growth/no growth boundaries for S. aureus with a logistic regression model. In this study, the boundaries of SEA production and S. aureus growth in broth were first performed with the logistic regression model, to evaluate the effects of environmental factors of temperature and salt. Consequently, the boundaries of SEA production and growth of S. aureus in temperature and salt concentration could be produced with the model in shaking and stationary cultures. The area where S. aureus cells would grow, but not produce SEA could be shown between the boundaries of SEA production and growth. Internal and external validations showed that the model could well describe and predict experimental results. Further, the maximum concentrations of SEA and cell population under various conditions of temperature and salt concentration were also compared between the shaking and stationary cultures. These results obtained in this study would become useful information in food industry to prevent S. aureus food poisoning outbreaks. PRACTICAL APPLICATION: Production/no production of staphylococcal enterotoxin A at various temperatures and salt concentrations in shaking and stationary cultures could be estimated well with a logistic regression model. Growth/no growth of staphylococcal cells under the same conditions was also well estimated with the model. The area where S. aureus cells would grow, but not produce SEA could be shown with the model. This present analysis would provide useful information in food industry to prevent staphylococcal food poisoning outbreaks.


Assuntos
Enterotoxinas/biossíntese , Sais/análise , Staphylococcus aureus/crescimento & desenvolvimento , Temperatura , Contagem de Colônia Microbiana , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Viabilidade Microbiana , Reprodutibilidade dos Testes , Intoxicação Alimentar Estafilocócica/prevenção & controle
9.
Environ Sci Pollut Res Int ; 26(30): 30575-30583, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29273979

RESUMO

The impacts of biofouling on the retention of pharmaceutically active compounds (PhACs) by a commercially available nanofiltration membrane (NF 270) were systematically studied. Biofouling was achieved through inoculating live and dead Pseudomonas aeruginosa into artificial wastewater. In comparison to a clean membrane, an increase in PhAC rejection during biofouling with live cells was observed. However, the rejection behaviors presented more complex changes during biofouling with dead cells: PhAC rejection was below the clean membrane in the early biofouling stage; however, in the later stage, PhAC rejection was above the clean membrane. In addition, PhAC rejection behaviors present the similar tendency as salt rejection under both biofouling conditions. In addition, solute rejections were much lower for biofouling with dead cells than those for biofouling with live cells. Combined with biofilm characterization under both biofouling conditions, we could conclude that biofilm enhanced osmotic pressure (BEOP) due to higher cell counts and biofilm thickness led to a decrease in PhAC retention, especially for the dead cells. In addition, more dominant steric exclusion in the later stage of biofouling due to higher extracellular polymeric substances (EPS) concentration on the membrane surface resulted in an increase in PhAC retention.


Assuntos
Incrustação Biológica , Filtração/instrumentação , Preparações Farmacêuticas/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/instrumentação , Biofilmes/crescimento & desenvolvimento , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Preparações Farmacêuticas/análise , Pseudomonas aeruginosa/fisiologia , Sais/análise , Sais/isolamento & purificação , Águas Residuárias/química , Águas Residuárias/microbiologia , Poluentes Químicos da Água/análise
10.
Acta Sci Pol Technol Aliment ; 17(4): 347-358, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30558391

RESUMO

BACKGROUND: Chlorella vulgaris alga is one of the most important additives for enhancing the nutritional content of conventional foods, hence positively affecting human health. This alga is known as a rich source of protein, fatty acids, fiber, essential vitamins and minerals. Also, it contains antioxidants, omega 3, antivi- ral and anticancer properties. The aim of this research is increasing the nutritional and potential therapeutic value of processed cheese by using Chlorella vulgaris alga, taking advantage of its high nutritional and health value. METHODS: The ingredients in the processed cheese blends were mature cheddar cheese, Ras cheese, butter, skimmed milk powder, Emulsifying salts (K-2394, S9s & S4), Chlorella vulgaris (in freeze- dried and slurry forms). Chemical, rheological and sensory evaluation properties were evaluated in processed cheese analogue (PCA) treatments when fresh and after three months of cold storage at 5–7°C. PCA treat- ments were enriched with 2%, 4% and 6% dried Chlorella vulgaris powder in the cheese blends and 4% Chlorella vulgaris slurry. RESULTS: The incorporation of alga into processed cheese led to an increase in their functional characteristics. The results of sensory evaluation of PCA samples demonstrated that 2% of alga addition was the best treat- ment, followed by 4%, but that the level of 6% was unacceptable to consumers. The studied alga enhanced the cheese analog with the high levels of selenium, zinc, iron, magnesium and potassium. Antioxidant activity in the cheese enhanced with Chlorella vulgaris was higher than the control sample. To improve some proper- ties of PCA, other emulsifying salts (S9S and S4) were tested and the alga was added in the form of slurry with value of 4% into the cheese blend. Both S9S and S4 emulsifying salts were good and the S4 was the best for oiling off and meltability. Also, when using the slurry of Chlorella vulgaris, the granular texture of the cheese analog completely disappeared. CONCLUSIONS: The results showed that the alga indeed increased nutrition values and health benefits to the processed cheese, making it a substantial functional food. Therefore, we recommend supporting the manu- facture of the processed cheese analogue with the addition of 2% Chlorella vulgaris alga in soft powder form and 4% Chlorella vulgaris alga in slurry form at the end of the processing.


Assuntos
Queijo/microbiologia , Chlorella vulgaris/metabolismo , Animais , Antioxidantes/análise , Bovinos , Ácidos Graxos/análise , Análise de Alimentos , Manipulação de Alimentos , Microbiologia de Alimentos , Qualidade dos Alimentos , Leite/química , Leite/microbiologia , Proteínas do Leite/análise , Valor Nutritivo , Sais/análise , Oligoelementos/análise
11.
Artigo em Inglês | MEDLINE | ID: mdl-30509904

RESUMO

Humans are globally increasing the salt concentration of freshwaters (i.e. freshwater salinization), leading to significant effects at the population, community and ecosystem level. The present theme issue focuses on priority research questions and delivers results that contribute to shaping the future research agenda on freshwater salinization as well as fostering our capacity to manage salinization. The issue is structured along five topics: (i) the estimation of future salinity and evaluation of the relative contribution of the different drivers; (ii) the physiological responses of organisms to alterations in ion concentrations with a specific focus on the osmophysiology of freshwater insects and the responses of different organisims to seawater intrusion; (iii) the impact of salinization on ecosystem functioning, also considering the connections between riparian and stream ecosystems; (iv) the role of context in moderating the response to salinization. The contributions scrutinise the role of additional stressors, biotic interactions, the identify of the ions and their ratios, as well as of the biogeographic and evolutionary context; and (v) the public discourse on salinization and recommendations for management and regulation. In this paper we introduce the general background of salinization, outline research gaps and report key findings from the contributions to this theme issue.This article is part of the theme issue 'Salt in freshwaters: causes, ecological consequences and future prospects'.


Assuntos
Ecossistema , Água Doce/química , Salinidade , Sais/análise , Poluentes Químicos da Água/análise , Sais/efeitos adversos , Poluentes Químicos da Água/efeitos adversos
12.
Artigo em Inglês | MEDLINE | ID: mdl-30509906

RESUMO

Salinization of surface waters is a global environmental issue that can pose a regional risk to freshwater organisms, potentially leading to high environmental and economic costs. Global environmental change including climate and land use change can increase the transport of ions into surface waters. We fit both multiple linear regression (LR) and random forest (RF) models on a large spatial dataset to predict Ca2+ (266 sites), Mg2+ (266 sites), and [Formula: see text] (357 sites) ion concentrations as well as electrical conductivity (EC-a proxy for total dissolved solids with 410 sites) in German running water bodies. Predictions in both types of models were driven by the major factors controlling salinity including geologic and soil properties, climate, vegetation and topography. The predictive power of the two types of models was very similar, with RF explaining 71-76% of the spatial variation in ion concentrations and LR explaining 70-75% of the variance. Mean squared errors for predictions were all smaller than 0.06. The factors most strongly associated with stream ion concentrations varied among models but rock chemistry and climate were the most dominant. The RF model was subsequently used to forecast the changes in EC that were likely to occur for the period of 2070 to 2100 in response to just climate change-i.e. no additional effects of other anthropogenic activities. The future forecasting shows approximately 10% and 15% increases in mean EC for representative concentration pathways 2.6 and 8.5 (RCP2.6 and RCP8.5) scenarios, respectively.This article is part of the theme issue 'Salt in freshwaters: causes, ecological consequences and future prospects'.


Assuntos
Mudança Climática , Íons/análise , Rios/química , Sais/análise , Monitoramento Ambiental , Água Doce , Alemanha
13.
Artigo em Inglês | MEDLINE | ID: mdl-30509909

RESUMO

Human activities have globally increased and altered the ion concentration of freshwater ecosystems. The proliferation of potash mines in Germany (especially intense in the early 1900s) constitutes a good example of it. The effluents and runoff coming from potash mines led to extreme salt concentrations (e.g. 72 g l-1 of total salt content, approx. 149 mS cm-1) in surrounding rivers and streams, causing ecosystem degradation (e.g. massive algal blooms and fish kills). This promoted scientific research that was mostly published in German, thereby being neglected by the wide scientific community. Here, the findings of the German literature on freshwater salinization are discussed in the light of current knowledge. German studies revealed that at similar ion concentrations potassium (K+) can be the most toxic ion to freshwater organisms, whereas calcium (Ca2+) could have a toxicity ameliorating effect. Also, they showed that salinization could lead to biodiversity loss, major shifts in the composition of aquatic communities (e.g. dominance of salt-tolerant algae, proliferation of invasive species) and alter organic matter processing. The biological degradation caused by freshwater salinization related to potash mining has important management implications, e.g. it could prevent many European rivers and streams from reaching the good ecological status demanded by the Water Framework Directive. Within this context, German publications show several examples of salinity thresholds and biological indices that could be useful to monitor and regulate salinization (i.e. developing legally enforced salinity and ion-specific standards). They also provide potential management techniques (i.e. brine collection and disposal) and some estimates of the economic costs of freshwater salinization. Overall, the German literature on freshwater salinization provides internationally relevant information that has rarely been cited by the English literature. We suggest that the global editorial and scientific community should take action to make important findings published in non-English literature more widely available.This article is part of the theme issue 'Salt in freshwaters: causes, ecological consequences and future prospects'.


Assuntos
Água Doce/análise , Salinidade , Sais/análise , Poluentes Químicos da Água/análise , Misturas Complexas , Alemanha , Mineração , Rios/química
14.
Environ Monit Assess ; 190(12): 716, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30421243

RESUMO

Microorganisms have great potential to control environmental pollution, particularly industrial sources of water pollution. Currently, leather industry is regarded as the most polluting and suffering from negative impacts due to the pollution it adds to the environment. Chromium, one of the hazardous pollutants discharged from tanneries, is highly toxic and carcinogenic in nature. Effective treatment of tannery effluent is a dire need of the era as a part of environmental management. Among all the wastewater treatment technologies, bioremediation is the most effective and environment-friendly tool to manage the water pollution. The present study evaluated the potential of 11 previously isolated bacterial strains, tolerant to high concentrations of salts and Cr for the bioremediation of tannery effluent. Among all the tested strains, Enterobacter sp. HU38, Microbacterium arborescens HU33, and Pantoea stewartii ASI11 were found most effective in reducing biological oxygen demand (BOD), chemical oxygen demand (COD), total dissolved solids (TDS), total suspended solids (TSS), and chromium (Cr) 70, 63, 57, 87, and 54%, respectively, of tannery effluent and proliferated well under highly toxic conditions, at 9 days of incubation. The pollutant removal efficacy of these bacterial strains can be improved by extending the incubation period or by increasing the amount of inoculum.


Assuntos
Biodegradação Ambiental , Resíduos Industriais/análise , Curtume , Poluentes Químicos da Água/análise , Carcinógenos/análise , Cromo/análise , Monitoramento Ambiental/métodos , Indústrias , Sais/análise , Águas Residuárias/análise , Poluição da Água/análise
15.
Food Chem ; 267: 75-82, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29934192

RESUMO

To update the current situation on salt, fat and fatty acid composition of processed foods, a study including a wide range of different food categories was conducted in Portugal. Different validated analytical techniques were used, and a PCA and correlation analysis were conducted to establish a trend between the different components in each food category. The highest salt content was found in snacks, fast-food, sauces and ready-to-eat meals, while the saturated fatty acids were higher (p < .05) in bakery products, cookies, biscuits and wafers, and snacks. The highest levels of trans fatty acids were found in the fast-food group, followed by the snacks, potato and potato-products and bakery products. A significant positive correlation (p < .05) was found between salt and fat content in ready-to-eat meals and in the potato and potato-products. The PCA analysis identified total fat, low trans fatty acids and high salt content as distinctive characteristics of some food categories.


Assuntos
Análise de Alimentos , Ácidos Graxos Trans/análise , Pão/análise , Cromatografia Gasosa , Fast Foods/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Análise de Componente Principal , Sais/análise
16.
Environ Pollut ; 239: 722-732, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29723822

RESUMO

Wetlands in the Prairie Pothole Region (PPR) of North America support macroinvertebrate communities that are integral to local food webs and important to breeding waterfowl. Macroinvertebrates in PPR wetlands are primarily generalists and well adapted to within and among year changes in water permanence and salinity. The Williston Basin, a major source of U.S. energy production, underlies the southwest portion of the PPR. Development of oil and gas results in the coproduction of large volumes of highly saline, sodium chloride dominated water (brine) and the introduction of brine can alter wetland salinity. To assess potential effects of brine contamination on macroinvertebrate communities, 155 PPR wetlands spanning a range of hydroperiods and salinities were sampled between 2014 and 2016. Brine contamination was documented in 34 wetlands with contaminated wetlands having significantly higher chloride concentrations, specific conductance and percent dominant taxa, and significantly lower taxonomic richness, Shannon diversity, and Pielou evenness scores compared to uncontaminated wetlands. Non-metric multidimensional scaling found significant correlations between several water quality parameters and macroinvertebrate communities. Chloride concentration and specific conductance, which can be elevated in naturally saline wetlands, but are also associated with brine contamination, had the strongest correlations. Five wetland groups were identified from cluster analysis with many of the highly contaminated wetlands located in a single cluster. Low or moderately contaminated wetlands were distributed among the remaining clusters and had macroinvertebrate communities similar to uncontaminated wetlands. While aggregate changes in macroinvertebrate community structure were observed with brine contamination, systematic changes were not evident, likely due to the strong and potentially confounding influence of hydroperiod and natural salinity. Therefore, despite the observed negative response of macroinvertebrate communities to brine contamination, macroinvertebrate community structure alone is likely not the most sensitive indicator of brine contamination in PPR wetlands.


Assuntos
Monitoramento Ambiental/métodos , Pradaria , Invertebrados/classificação , Sais/análise , Áreas Alagadas , Animais , Biodiversidade , América do Norte , Indústria de Petróleo e Gás , Salinidade
17.
Environ Monit Assess ; 190(5): 313, 2018 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-29705878

RESUMO

A comprehensive comparative validation for two different types of dissolved oxygen (DO) analyzers, amperometric and optical, is presented on two representative commercial DO analyzers. A number of performance characteristics were evaluated including drift, intermediate precision, accuracy of temperature compensation, accuracy of reading (under different measurement conditions), linearity, flow dependence of the reading, repeatability (reading stability), and matrix effects of dissolved salts. The matrix effects on readings in real samples were evaluated by analyzing the dependence of the reading on salt concentration (at saturation concentration of DO). The analyzers were also assessed in DO measurements of a number of natural waters. The uncertainty contributions of the main influencing parameters were estimated under different experimental conditions. It was found that the uncertainties of results for both analyzers are quite similar but the contributions of the uncertainty sources are different. Our results imply that the optical analyzer might not be as robust as is commonly assumed; however, it has better reading stability, lower stirring speed dependence, and typically requires less maintenance. On the other hand, the amperometric analyzer has a faster response and wider linear range. Both analyzers seem to have issues with the accuracy of temperature compensation. The approach described in this work will be useful to practitioners carrying out DO measurements for ensuring reliability of their measurements.


Assuntos
Monitoramento Ambiental/métodos , Oxigênio/análise , Monitoramento Ambiental/instrumentação , Reprodutibilidade dos Testes , Sais/análise
18.
J Pharm Sci ; 107(7): 1870-1878, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29499276

RESUMO

The present study reports a high-throughput screening method for the salt formation of amine-containing active pharmaceutical ingredients (APIs) based on fluorescence measurements. A free form amine API was alkynylated by a solid-vapor reaction using propargyl bromide, and a fluorescent compound was produced by a subsequent reaction using 9-azidomethylanthracene. In contrast, salts were inert to propargyl bromide; thus, no fluorescence was observed. Samples for salt screening were prepared by grinding haloperidol with various counter acids, and these mixtures were derivatized in a 96-well microplate to determine whether the salt formation had occurred between haloperidol and the counter acids. Samples that turned into fluorescent and nonfluorescent were confirmed to be free form and salt form, respectively, using powder X-ray diffraction and Raman spectroscopy. In conclusion, our method adequately functions as an indicator of the salt formation of amine APIs. Further, this method allows for the rapid evaluation of the salt formation of APIs using 96-well microplates without the need for special reagents or techniques; thus, it is valuable for the discovery of an optimal salt form of newly developed amine APIs in the pharmaceutical industry.


Assuntos
Aminas/química , Preparações Farmacêuticas/química , Sais/análise , Espectrometria de Fluorescência/métodos , Difração de Pó , Espectrometria de Fluorescência/economia , Análise Espectral Raman , Difração de Raios X
19.
Environ Toxicol Chem ; 37(5): 1330-1339, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29297606

RESUMO

Field and laboratory studies have shown that mayflies (Ephemeroptera) tend to be relatively sensitive to elevated major ion concentrations, but little is known about how ionic composition influences these responses. The present study evaluated the acute toxicity of major ion salts to the mayfly Neocloeon triangulifer over a range of background water quality conditions. The mayfly was particularly sensitive to Na2 SO4 , with the median lethal concentration (LC50) of 1338 mg SO4 /L being lower than LC50s reported for 7 other species at that hardness. Increasing hardness of the dilution water from 30 to 150 mg/L (as CaCO3 ) resulted in doubling of LC50s for sodium salts, and an approximately 1.5-fold increase in LC50 for MgSO4 . Potassium salt toxicity was not strongly influenced by hardness, consistent with findings for other species. When hardness was held constant but the Ca to Mg ratio was manipulated, the ameliorative effect on Na2 SO4 and NaCl did not appear as strong as when hardness was varied; but for MgSO4 the amelioration relative to Ca activity was similar between the 2 experiments. The toxicity of K salts to N. triangulifer was similar to Na salts on a millimolar basis, which contrasts with several other species for which K salts have been much more toxic. In addition, the toxicity of KCl to N. triangulifer was not notably affected by Na concentration, as has been shown for Ceriodaphnia dubia. Finally, plotting LC50s in terms of ion activity (Cl, SO4 , Na, Mg, or K) over the range of Ca activities in dilution water resulted in significant positive relationships, with comparable slopes to those previously observed for C. dubia over the same range of Ca activities. Environ Toxicol Chem 2018;37:1330-1339. © 2018 SETAC.


Assuntos
Ephemeroptera/efeitos dos fármacos , Íons/toxicidade , Testes de Toxicidade Aguda , Água/química , Animais , Cálcio/análise , Cladóceros/efeitos dos fármacos , Água Doce , Dureza , Dose Letal Mediana , Magnésio/análise , Potássio/análise , Sais/análise , Sódio/análise , Poluentes Químicos da Água/toxicidade
20.
J Appl Microbiol ; 124(1): 197-208, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29091336

RESUMO

AIMS: Accumulation of carbon dioxide (CO2 ) in cucumber fermentations is known to cause hollow cavities inside whole fruits or bloaters, conducive to economic losses for the pickling industry. This study focused on evaluating the use of a malic acid decarboxylase (MDC)-deficient starter culture to minimize CO2 production and the resulting bloater index in sodium chloride-free cucumber fermentations brined with CaCl2 . METHODS AND RESULTS: Attempts to isolate autochthonous MDC-deficient starter cultures from commercial fermentations, using the MD medium for screening, were unsuccessful. The utilization of allochthonous MDC-deficient starter cultures resulted in incomplete utilization of sugars and delayed fermentations. Acidified fermentations were considered, to suppress the indigenous microbiota and favour proliferation of the allochthonous MDC-deficient Lactobacillus plantarum starter cultures. Inoculation of acidified fermentations with L. plantarum alone or in combination with Lactobacillus brevis minimally improved the conversion of sugars. However, inoculation of the pure allochthonous MDC-deficient starter culture to 107 CFU per ml in acidified fermentations resulted in a reduced bloater index as compared to wild fermentations and those inoculated with the mixed starter culture. CONCLUSIONS: Although use of an allochthonous MDC-deficient starter culture reduces bloater index in acidified cucumber fermentations brined with CaCl2 , an incomplete conversion of sugars is observed. SIGNIFICANCE AND IMPACT OF THE STUDY: Economical losses due to the incidence of bloaters in commercial cucumber fermentations brined with CaCl2 may be reduced utilizing a starter culture to high cell density.


Assuntos
Proteínas de Bactérias/metabolismo , Dióxido de Carbono/análise , Carboxiliases/metabolismo , Cucumis sativus/microbiologia , Lactobacillus plantarum/enzimologia , Malatos/metabolismo , Cloreto de Sódio/análise , Proteínas de Bactérias/genética , Dióxido de Carbono/metabolismo , Carboxiliases/genética , Fermentação , Microbiologia de Alimentos , Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo , Sais/análise
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