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1.
Water Res ; 168: 115146, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31627136

RESUMO

An energy recovery technique using a high-current bi-directional dc-dc converter for membrane capacitive de-ionization (mCDI) of brackish waters is described and it's performance assessed in a pilot-scale prototype. The energy recovery system is shown to reduce the energy consumption of the pilot-scale mCDI unit, powered by photovoltaics and with battery storage, by between 30 and 40%. Use of a stopped flow process also enables water recovery of up to 87%. The contributions to energy consumption in the system are quantified with the insights gained from this analysis enabling the selection of an optimum voltage range for desorption termination that maximizes the daily recovered energy. The experimental results demonstrate that energy usage by the mCDI process of lower than 0.4 kWh/m3 is achievable with almost 40% of the energy supplied by the batteries recovered.


Assuntos
Purificação da Água , Adsorção , Eletrodos , Membranas Artificiais , Águas Salinas , Cloreto de Sódio
2.
Water Res ; 168: 115186, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655437

RESUMO

Flow-electrode capacitive deionization (FCDI) is an attractive variant of CDI with distinct advantages over fixed electrode CDI including the capability for seawater desalination, high flow efficiency and easy management of the electrodes. Challenges exist however in increasing treatment capacity with this attempted here through use of a membrane stack configuration. By comparison of standardised metrics (in particular, average salt removal rate (ASRR), energy normalized removed salt (ENRS) and productivity), results show that that an FCDI system with two pairs of ion exchange membranes had the highest efficiency in desalting a brackish influent (1000 mg L-1) to potable levels (∼150 mg L-1) at higher ASRR and ENRS. Further increase in the number of membrane pairs resulted in a decrease in current efficiency, likely as a result of the dominance of electrodialysis. Results of this study provide proof of concept that (semi-)continuous desalination can be achieved in FCDI at high energy efficiency (13.8%-20.2%) and productivity (> 100 L m-2 h-1) and, importantly, provide insight into possible approaches to scaling up FCDI such that energy-efficient water desalination can be achieved.


Assuntos
Purificação da Água , Adsorção , Eletrodos , Troca Iônica , Cloreto de Sódio
3.
Food Chem ; 303: 125401, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466031

RESUMO

Salt addition and thermal pretreatment were used to improve the freeze-thaw stability of Pickering emulsion gels (PEGs) stabilized by compound proteins. Thermal pretreatment with the presence of salt could promote the formation of gel-like structure and alter the interactions between the emulsion droplets of PEGs, sequentially increase the resistance of the PEGs to water separation, creaming, and oiling-off during freeze-thaw cycles (freeze at -20 °C for 22 h and thawing at 37 °C for 2 h), especially at higher salt levels (200 and 500 mM). Microstructures indicated that the presence of high salt concentration and heat pretreatment could help to maintain the gel-like structures of PEGs during freeze-thaw cycles. Overall, our results showed that novel viscoelastic food materials with good freeze-thaw stability can be produced by controlling the electrostatic interactions between the emulsion droplets and the gelation of emulsion gels. These materials may be useful for application in frozen food products.


Assuntos
Fixadores/química , Géis/química , Emulsões/química , Congelamento , Temperatura Alta , Óleos/química , Concentração Osmolar , Cloreto de Sódio/análise , Água/química
4.
Niger J Clin Pract ; 22(10): 1328-1334, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31607720

RESUMO

Objective: The aim of the this study was to evaluate the effect of honey on the healing of tooth extraction wounds in children 4‒9 years of age. Subjects and Methods: In the present randomized clinical trial, 51 patients, 4‒9 years of age were selected randomly. All the subjects required extraction of one deciduous molar tooth. The subjects were randomly assigned to two groups. In group 1, after extraction of the tooth, the dentist used a cotton swab applicator to place a layer of honey on a piece of gauze moistened with normal saline solution (NSS) and placed it on the socket. In group 2, honey was not used; rather, NSS was applied. On days 3 and 7 after tooth extraction, the wound sizes were measured. Results: In both groups, the wound sizes decreased significantly on the third day compared with baseline and on the seventh day compared with the third day (P < 0.05). On the third and seventh days after tooth extraction, wound sizes in the honey group were significantly lower than those in the NSS group (P < 0.05). Conclusion: Honey resulted in a decrease in wound sizes and faster healing after extraction of teeth in children. Therefore, use of honey can be recommended after minor surgeries in the oral cavity.


Assuntos
Apiterapia/métodos , Mel , Extração Dentária , Alvéolo Dental , Cicatrização/efeitos dos fármacos , Administração Tópica , Bandagens , Criança , Pré-Escolar , Assistência Odontológica , Feminino , Humanos , Masculino , Cloreto de Sódio/uso terapêutico , Alvéolo Dental/efeitos dos fármacos , Alvéolo Dental/patologia , Resultado do Tratamento
5.
Zhonghua Zhong Liu Za Zhi ; 41(10): 771-774, 2019 Oct 23.
Artigo em Chinês | MEDLINE | ID: mdl-31648500

RESUMO

Objective: To compare the efficiency of saline irrigation, antibiotics irrigation and high-concentration antibiotics perfusion with tube drainage in the treatment of infectious effusion. Methods: Clinical and sonographic features of abdominal and pelvic infectious effusion of 64 patients with malignant tumor collected from September 2013 to September 2017 were retrospectively analyzed. The changes of effusion size and temperature, catheterization time were evaluated in saline irrigation group and antibiotics irrigation group. The catheterization time was compared between antibiotics irrigation group and high-concentration antibiotics perfusion group. Results: The effective rates of the saline irrigation group and the antibiotics irrigation group were 68.6% and 86.8%, respectively, and the times of catheterization were 11.9±8.4 days and 7.8±4.8 days, respectively, with significantly statistical difference (both P<0.05). However, the effective rates of the antibiotics irrigation group and the high concentration antibiotic perfusion group were 86.8% and 100.0%, respectively (P=0.067), while the times of catheterization were 7.8±4.8 days and 3.6±3.1 days, respectively (P<0.001). Conclusion: The antibiotic irrigation with tube drainage, especially the high concentration perfusion is more effective than saline in the treatment of abdominal and pelvic infection effusion.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/terapia , Drenagem , Infecção Pélvica/terapia , Cloreto de Sódio/uso terapêutico , Irrigação Terapêutica , Infecções Bacterianas/complicações , Humanos , Infecção Pélvica/microbiologia , Complicações Pós-Operatórias/terapia , Período Pós-Operatório , Estudos Retrospectivos , Resultado do Tratamento
6.
Microbiol Res ; 229: 126331, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31521945

RESUMO

The uses of halotolerant bacteria isolated from naturally saline habitats have the potential to be useful crop protection agents for plants in stressful conditions. These beneficial microbes generate several plant growth regulators and bioactive molecules, which enhance plant protection from adversities, such as plant pathogens, salts and metals stresses. In this study, 15 halotolerant bacterial strains endowed with important antimicrobial activities were isolated from Sfax solar saltern (Tunisia). All of these strains were characterized by biochemical and molecular tools aiming to investigate their in-vitro and in-vivo antifungal potentialities, plant growth promotion capabilities and metal tolerance abilities under saline stress condition. The 16S rRNA gene sequencing showed that the isolated strains were affiliated to different phylum and three species were described for the first time as plant growth promoting strains (Idiomarina zobelli FMH6v, Nesterenkonia halotolerans FMH10 and Halomonas janggokensis FMH54). The tested strains exhibited several potentialities: to tolerate high salt and heavy metal concentrations, to produce biosurfactants, exopolysaccharides and extracellular hydrolytic enzymes, to form biofilms and to liberate plant promoting substances. Eight strains were able to protect tomatoes fruits from the proliferation of the fungal disease caused by Botrytis cinerea and six strains improved plant vigor indexes. Principal component analysis showed an important correlation between in-vitro and in-vivo potentialities and two strains Bacillus velezensis FMH2 and Bacillus subtilis subsp. spizizenii FMH45 were statistically considered as the most effective strains in protecting plants from fungal pathogens attack and promoting the growth of tomatoes seedlings under saline and multi heavy-metals stress conditions.


Assuntos
Bactérias/isolamento & purificação , Fenômenos Fisiológicos Bacterianos , Lycopersicon esculentum/microbiologia , Água do Mar/microbiologia , Cloreto de Sódio/metabolismo , Bactérias/classificação , Bactérias/genética , Botrytis/fisiologia , Lycopersicon esculentum/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Salinidade , Água do Mar/química , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Cloreto de Sódio/análise , Estresse Fisiológico , Tunísia
7.
Forensic Sci Int ; 302: 109936, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31493923

RESUMO

Stomach content is a matrix often applied in post-mortem cases. It is especially important in oral intoxication cases. The main advantages are the usually high concentration of analytes and the lack of biotransformation process. Still, even with extensive sample preparation, the final extract is not always suitable for analysis. The aim of this study was to develop an alternative method using QuEChERS for the extraction of drugs and pesticides from postmortem stomach content. Sample preparation started acetonitrile with 1% of acetic acid and QuEChERS salts. Later, the initial extract was cleaned-up using the EMR-Lipid sorbent. Residual water was withdrawn with MgSO4/NaCl in the third step and a final step with MgSO4. Vigorous shaken and centrifugation was performed after each step. The final supernatant was evaporated, re-suspended, and injected into GC-MS in full scan mode. This approach was successfully applied to stomach content, resulting in clean extracts, with low lipid levels. The method was able to detected target drugs and pesticides (cocaine, tramadol, diazepam, amytriptiline, phenobarbital, prochloraz, diazinon, heptachlor, permethrin, malathion and carbaryl) at the limit of detection of 0.1 mg/g or 0.1 mg/L. Recovery was over 70% for the majority of analytes, precision and accuracy was within acceptable range. The method was also applied to real forensic cases and carbofuran, terbuphos and fluoxetine was detected likewise. This work demonstrates that this method can provide an effective clean-up in high lipids samples such as stomach content, and can be used to analyze of pesticides and drugs in forensic cases.


Assuntos
Toxicologia Forense/métodos , Conteúdo Gastrointestinal/química , Ácido Acético , Acetonitrilos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Sulfato de Magnésio , Entorpecentes/análise , Praguicidas/análise , Preparações Farmacêuticas/análise , Acetato de Sódio , Cloreto de Sódio
8.
Cell Physiol Biochem ; 53(4): 638-647, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31556253

RESUMO

BACKGROUND/AIMS: Prolonged hyperosmotic shrinkage evokes expression of osmoprotective genes via nuclear factor NFAT5-mediated pathway and activates Na+ influx via hypertonicity-induced cation channels (HICC). In human umbilical vein endothelial cells (HUVEC) elevation of intracellular sodium concentration ([Na+]i) triggers transcription of dozens of early response genes (ERG). This study examined the role of monovalent cations in the expression of Na+i-sensitive ERGs in iso- and hyperosmotically shrunken HUVEC. METHODS: Cell volume was measured by 3D reconstruction of cell shape and as 14C-urea available space. Intracellular Na+ and K+ content was measured by flame atomic absorption spectrometry. ERG transcription was estimated by RT-PCR. RESULTS: Elevation of medium osmolality by 150 mM mannitol or cell transfer from hypo- to isosmotic medium decreased cell volume by 40-50%. Hyperosmotic medium increased [Na+]i by 2-fold whereas isosmotic shrinkage had no impact on this parameter. Hyperosmotic but not isosmotic shrinkage increased up-to 5-fold the content of EGR1, FOS, ATF3, ZFP36 and JUN mRNAs. Expression of these ERGs triggered by hyperosmotic shrinkage and Na+,K+-ATPase inhibition by 0.1 µM ouabain exhibited positive correlation (R2=0.9383, p=0.0005). Isosmotic substitution of NaCl by N-methyl-D-glucamine abolished an increment of [Na+]i and ERG expression triggered by mannitol addition. CONCLUSION: Augmented expression of ERGs in hyperosmotically shrunken HUVEC is mediated by elevation of [Na+]i.


Assuntos
Tamanho Celular , Sódio/metabolismo , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Meglumina/farmacologia , Ouabaína/farmacologia , Potássio/metabolismo , Cloreto de Sódio/farmacologia , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/metabolismo , Tristetraprolina/genética , Tristetraprolina/metabolismo
9.
Biochem Med (Zagreb) ; 29(3): 031001, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31379463

RESUMO

Introduction: Phlebotomy is an error-prone process in which mistakes are difficult to reveal. This case report describes the effect on laboratory results originating from a blood sample collected in close proximity to an intravenous catheter. Materials and methods: A 69-year-old male patient was referred to the Emergency department where pneumonia was suspected. Phlebotomy was performed to collect blood samples to assess electrolytes, renal function, liver function, infection and haematological parameters. Results: The laboratory analysis showed reduced potassium and calcium concentrations. To prevent life-threatening cardiac failure the clinician decided to correct those electrolytes. Remarkably, the electrocardiogram showed no abnormalities corresponding to hypokalaemia and hypocalcaemia. This observation, in combination with an overall increase in laboratory parameters with the exception of sodium and chloride, led to the suspicion of a preanalytical error. Retrospectively, an intravenous catheter was inserted in close proximity of the puncture place but no continuous infusion was started prior to phlebotomy. However, the intravenous catheter was flushed with sodium chloride. Since potential other causes were excluded, the flushing of the intravenous catheter with sodium chloride prior to phlebotomy was the most probable cause for the deviating laboratory results and subsequently for the unnecessary potassium and calcium suppletion. Conclusion: This case underlines the importance of caution in the interpretation of laboratory results obtained from specimens that are collected in the proximity of an intravenous catheter, even in the absence of continuous infusion.


Assuntos
Cateteres , Flebotomia/métodos , Idoso , Cálcio/sangue , Eletrocardiografia , Serviço Hospitalar de Emergência , Insuficiência Cardíaca/diagnóstico , Humanos , Masculino , Potássio/sangue , Fase Pré-Analítica , Cloreto de Sódio/química
10.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2549-2557, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418177

RESUMO

We measured soil water and salt distribution characteristics at 0-40 cm soil depth in a silvopastoral system of Fraxinus chinensis and Robinia pseudoacacia mixed forest × Medicago sativa, which is located in Land Use Scientific Observation Field Base of Ministry of Land and Resource in Wudi, Shandong Province, China. The moving split-window technique was used to analyze the internal-system edge effect. The results showed that both soil water and salt contents in this system heterogeneously distributed in the horizontal direction. The variation of soil water was greater and that of soil salt contents was the smaller when closer to the soil surface. With the mixed forest tree row as the boundary line, the contents of soil water and salt on both sides showed similar change trend. With the decreases of distance to the tree row, soil water content reduced first and then increased but the salt contents had a stable fluctuation at 0-10 cm soil layer. Soil water content showed a trend of decrease-flat-decrease but the salt contents first enhanced and then reduced at 10-20 cm soil layer, respectively. At the deeper soil layer (20-40 cm), the water content fluctuated stably but the salt content continued increasing. Both the contents of soil water and salt in the vertical direction increased significantly with soil depth. Except HCO3- and K+, there was a similar change trend between ions and total salt content in the soil of silvopastoral system, and the correlation between these ions and total salt content was Na+>Cl->SO42->Mg2+>Ca2+. Based on the technique of moving split-window, the edge effect zone of soil water in the silvopastoral system was 2.5 m from the east side of the tree row to 2 m from the west side. Soil salinity in the silvopastoral system was mainly affected by the tree row within the range of 1.0 m, and by both of the tree row and M. sativa within the range of 1.0-3.0 m.


Assuntos
Ecossistema , Rios , Solo/química , China , Salinidade , Cloreto de Sódio , Água
11.
Microbiol Res ; 228: 126307, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422229

RESUMO

Bacterial plasmids carry genes that code for additional traits such as osmoregulation, CO2 fixation, antibiotic and heavy metal resistance, root nodulation and nitrogen fixation. The main objective of the current study was to identify plasmid-conferring osmoregulatory genes in bacteria isolated from rhizospheric and non-rhizospheric soils of halophytes (Salsola stocksii and Atriplex amnicola). More than 55% of halophilic bacteria from the rhizosphere and 70% from non-rhizospheric soils were able to grow at 3 M salt concentrations. All the strains showed optimum growth at 1.5-3.0 M NaCl. Bacterial strains from the Salsola rhizosphere showed maximum (31%) plasmid elimination during curing experiments as compared to bacterial strains from the Atriplex rhizosphere and non-rhizospheric soils. Two plasmid cured strains Bacillus HL2HP6 and Oceanobacillus HL2RP7 lost their ability to grow in halophilic medium, but they grew well on LB medium. The plasmid cured strains also showed a change in sensitivity to specific antibiotics. These plasmids were isolated and transformed into E. coli strains and growth response of wild-type and transformed E. coli strains was compared at 1.5-4 M NaCl concentrations. Chromosomal DNA and plasmids from Bacillus filamentosus HL2HP6 were sequenced by using high throughput sequencing approach. Results of functional analysis of plasmid sequences showed different proteins and enzymes involved in osmoregulation of bacteria, such as trehalose, ectoine synthetase, porins, proline, alanine, inorganic ion transporters, dehydrogenases and peptidases. Our results suggested that plasmid conferring osmoregulatory genes play a vital role to maintain internal osmotic balance of bacterial cells and these genes can be used to develop salt tolerant transgenic crops.


Assuntos
Bactérias/genética , Osmorregulação/genética , Plasmídeos/genética , Plasmídeos/isolamento & purificação , Rizosfera , Tolerância ao Sal/genética , Plantas Tolerantes a Sal/microbiologia , Alanina/metabolismo , Diamino Aminoácidos/metabolismo , Antibacterianos/farmacologia , Atriplex/microbiologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Transferência Genética Horizontal , Oxirredutases , Peptídeo Hidrolases , Filogenia , Porinas/metabolismo , Prolina/metabolismo , Cloreto de Sódio , Solo , Microbiologia do Solo , Trealose/metabolismo
12.
Microbiol Res ; 228: 126299, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422231

RESUMO

Wastewaters from textile dyeing industries represent an ecological concern, notably due to the known toxicity of azo dyes to the local microbiome and human health. Although physicochemical approaches are the rule for the treatment of industrial effluents, biological strategies such as enzyme-mediated dye destaining is a promising alternative. Notwithstanding a broad range of microorganisms, including fungi, algae, yeast, and bacteria, display dye-destaining properties, most of the literature has focused in ligninolytic fungi, leaving other classes of organisms somehow ignored. In this study, six endophytic strains isolated from Maytenus ilicifolia were studied for their destaining activity. The phylogenetic and morphological analysis allowed the identification of strain LGMF1504 as Neopestalotiopsis sp. LGMF1504 that decolorized several commercial dyes as the result of a mycelium-associated laccase. The enzyme expression was modulated by carbon and nitrogen content in the culture medium, it was weakly affected by the presence of aromatic compounds and metal ions while some common laccase mediators improved the destaining activity onto dye substrates. The best culture condition observed for laccase activity was a basic culture medium containing 5 g L-1 starch and 15 g L-1 ammonium tartrate. The laccase activity showed low substrate specificity and almost unaltered performance in a wide range of pH values and NaCl concentrations, suggesting the potential of Neopestalotiopsis sp. LGMF1504 for biodegradation approaches.


Assuntos
Corantes/metabolismo , Endófitos/metabolismo , Lacase/metabolismo , Micélio/metabolismo , Compostos Azo/toxicidade , Biodegradação Ambiental , Carbono , Corantes/toxicidade , DNA Fúngico , Endófitos/classificação , Endófitos/isolamento & purificação , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Fungos/metabolismo , Concentração de Íons de Hidrogênio , Metais , Tipagem de Sequências Multilocus , Nitrogênio , Filogenia , Cloreto de Sódio/análise , Indústria Têxtil , Águas Residuárias
13.
J Sci Food Agric ; 99(15): 6973-6980, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31414485

RESUMO

BACKGROUND: Plants activate defense mechanisms to cope with adverse environmental conditions, leading to the accumulation and / or depletion of general and specialized metabolites. In this study, a multiplatform untargeted metabolomics strategy was employed to evaluate metabolic changes in strawberry fruit of cv. Camarosa grown under osmotic stress conditions. Liquid chromatography-mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) data from strawberries grown under two water-deficit conditions, irrigated at 95% crop evapotranspiration (ETc) and 85% ETc, and one excess salt condition with a 80 mmol L-1 NaCl solution, were analyzed to determine treatment effects on fruit metabolism. RESULTS: Multivariate principal component analysis, orthogonal projections to latent structures - discriminant analysis (OPLS-DA), and univariate statistical analyses were applied to the data set. While multivariate analyses showed group separation by treatment, T-tests and fold change revealed 12 metabolites differentially accumulated in strawberries from different treatments - among them phenolic compounds, glycerophospholipids, phytosterols, carbohydrates, and an aromatic amino acid. CONCLUSION: Untargeted metabolomic analysis allowed for the annotation of compounds differentially accumulated in strawberry fruit from plants grown under osmotic stress and non-stressed plants. The metabolic disturbance in plants under stress involved metabolites associated with the inhibition of reactive oxygen species and cell-wall and membrane lipid biosynthesis, which might serve as osmotic stress biomarkers. © 2019 Society of Chemical Industry.


Assuntos
Fragaria/química , Frutas/metabolismo , Cromatografia Líquida , Fragaria/crescimento & desenvolvimento , Fragaria/metabolismo , Frutas/química , Frutas/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Metabolômica , Pressão Osmótica , Cloreto de Sódio/análise , Cloreto de Sódio/metabolismo , Espectrometria de Massas em Tandem , Água/análise , Água/metabolismo
14.
Int J Food Microbiol ; 308: 108303, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31437694

RESUMO

Environmental conditions during ripening of dry-cured meat products favour growth of fungal population on their surface. Some of these moulds can produce mycotoxins. Paprika is one of the ingredients usually used in the formulation of raw-cured sausages, and its addition could influence the growth and production of mycotoxins of the moulds present in these products. In this work the effect of Spanish smoked paprika "Pimentón de la Vera" on growth of Aspergillus parasiticus and Penicillium nordicum and production of aflatoxins B1 (AFB1), G1 (AFG1) and ochratoxin A (OTA) respectively, was evaluated. Moulds were grown in a culture medium made from lyophilized fresh pork meat added with 4% salt and different concentrations of Spanish smoked paprika (1, 2 and 3%) at several water activity values (0.98, 0.94 and 0.87) and temperature (20-25 °C), to simulate conditions usually found during ripening of dry-cured meat products. Mould growth was evaluated by measuring the diameter of the colony every 24 h, and the production of mycotoxins by UHPLC-MS/MS every 2 days, during 10 days of incubation. Addition of paprika favours growth of the two mould species tested. However, the synthesis of mycotoxins was reduced at 0.94 and 0.98 aw when at least a 2% of paprika was added. Therefore, the addition of Spanish smoked paprika at 2-3% in the formulations may help to minimize AFs and OTA production in dry-cured meat products such as loins or "chorizo" sausages.


Assuntos
Aflatoxina B1/biossíntese , Aspergillus/crescimento & desenvolvimento , Capsicum/química , Produtos da Carne/microbiologia , Ocratoxinas/biossíntese , Penicillium/crescimento & desenvolvimento , Animais , Aspergillus/metabolismo , Microbiologia de Alimentos , Penicillium/metabolismo , Fumaça , Cloreto de Sódio/análise , Suínos , Espectrometria de Massas em Tandem , Temperatura Ambiente , Água
15.
Int J Food Microbiol ; 308: 108308, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31466020

RESUMO

Cattle are a reservoir for enterohemorrhagic Escherichia coli (EHEC), and ground beef is a major vehicle for human infection with EHEC. Heat resistance of E. coli, including EHEC, is impacted by NaCl and other additives. This study aimed to evaluate the effect of NaCl and other additives on the heat resistance of E. coli in beef patties. E. coli AW1.7ΔpHR1(pLHR) with the locus of heat resistance (LHR), E. coli AW1.7ΔpHR1(pRK767) without LHR, or a 5-strain cocktail of EHEC were inoculated (107-108 CFU/g) into ground beef (15% fat) with NaCl (0-3%), marinade, carvacrol (0.1%), potassium lactate (3%) or chitosan (0.1%) following different protocols. Patties were grilled immediately, or stored in sterile bags for two days at 4 °C prior to grilling to a core temperature of 71 °C. Cell counts of LHR-positive E. coli AW1.7ΔpHR1(pLHR) were higher than that of the isogenic LHR-negative E. coli AW1.7ΔpHR1(pRK767) by >3 log10 (CFU/g) after cooking. Addition of 3% NaCl increased survival of E. coli AW1.7ΔpHR1(pRK767) and the EHEC cocktail while cell counts of the heat resistant strains were not changed. A protective effect of NaCl was not observed with E. coli AW1.7ΔpHR1(pRK767) or EHEC if cells of E. coli were cooled to 4 °C prior to mixing with cold meat and NaCl, indicating that the response of E. coli to osmotic shock contributes to this effect. Chitosan enhanced the thermal destruction of LHR-positive E. coli AW1.7ΔpHR1(pLHR) in ground beef stored at 4 °C for 2 days, while marinade, carvacrol, or potassium lactate had no such effect, indicating that chitosan can be characterized as an effective hurdle concept to reduce the potential risk of LHR-positive pathogen to meat safety.


Assuntos
Quitosana/farmacologia , Escherichia coli Êntero-Hemorrágica/efeitos dos fármacos , Produtos da Carne/microbiologia , Carne/microbiologia , Cloreto de Sódio/farmacologia , Animais , Bovinos , Contagem de Colônia Microbiana , Culinária/métodos , Escherichia coli Êntero-Hemorrágica/fisiologia , Temperatura Alta , Humanos , Monoterpenos/farmacologia
16.
J Food Sci ; 84(9): 2499-2506, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31393020

RESUMO

As many of the maternal and child health complications result from folic acid, iron, and iodine deficiencies; it makes sense to combat these simultaneously. We have developed cost-effective technology to deliver these three micronutrients simultaneously through salt. Our goal was to retain at least 70% of the micronutrients during 6 months of storage. The fortified salt was formulated by spraying a solution that contained 2% iodine and 0.5% or 1% folic acid onto salt and adding encapsulated ferrous fumarate. The formulated triple fortified salt contained 1,000 ppm iron, 50 ppm iodine, and 12.5 or 25 ppm folic acid. The spray solution and the salt were stored for 2 and 6 months respectively at 25, 35, and 45 °C 60 to 70% relative humidity. Even at 45 °C, over 70% of both iodine and folic acid were retained in the salt. The best formulation based on the color of the salt and stability of iodine and folic acid contained 12.5 ppm folic acid, 50 ppm iodine, and 1,000 ppm iron. These results indicate that iron, iodine, and folic acid can be simultaneously delivered to a vulnerable population through salt using the technology described. Also, the quality control of the process can be developed around pteroic acid that was detected as a primary degradation product of folic acid. PRACTICAL APPLICATION: The technology developed is already transferred to India for industrial scale up. When fully operational, the technology will simultaneously solve iron, iodine, and folic acid deficiencies in vulnerable populations at a very low cost.


Assuntos
Composição de Medicamentos/métodos , Compostos Ferrosos/química , Ácido Fólico/química , Iodo/química , Cloreto de Sódio/química , Composição de Medicamentos/economia , Estabilidade de Medicamentos , Alimentos Fortificados/análise , Alimentos Fortificados/economia , Índia , Micronutrientes/química
17.
Water Res ; 165: 114995, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31450221

RESUMO

Deionization devices that use intercalation reactions to reversibly store and release cations from solution show promise for energy-efficient desalination of alternative water resources. Intercalation materials often display low electronic conductivity that results in increased energy consumption during desalination. Accordingly, we performed experiments to quantify the impact of the size and mass fraction of conductive additives and insulative active particles on the effective electronic conductivity, ionic conductivity, and hydraulic permeability of porous electrodes. We find that Ketjen black conductive additives with nodules <50 nm in diameter produce superior electronic conductivity at lower mass fractions than the larger carbon blacks commonly used in capacitive deionization. Hydraulic permeability and effective ionic conductivity depend weakly on carbon black content and size, though smaller active particles decrease hydraulic permeability. Based on these results we analyzed the energy consumption and salt removal rate of different electrode formulations by constructing an electrochemical Ashby plot predicting the variation of desalination performance with electrode transport properties. Optimized electrodes containing insulative Prussian blue analogue (PBA) particles were then fabricated and used in an experimental cation intercalation desalination (CID) cell with symmetric electrodes. For 100 mM NaCl influent energy consumption varied from 7 to 33 kJ/mol when current density increased from 1 to 8 mA/cm2, approaching ten-fold increased salt removal rate at similar energy consumption levels to past CID demonstrations. Complementary numerical and analytical modeling indicates that further improvements in energy consumption and salt removal rate are attainable by enhancing transport in solution and within PBA agglomerates.


Assuntos
Purificação da Água , Condutividade Elétrica , Eletrodos , Porosidade , Cloreto de Sódio
18.
J Microbiol ; 57(9): 717-724, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31452042

RESUMO

Salterns are hypersaline extreme environments with unique physicochemical properties such as a salinity gradient. Although the investigation of microbiota in salterns has focused on archaea and bacteria, diverse fungi also thrive in the brine and soil of salterns. Fungi isolated from salterns are represented by black yeasts (Hortaea werneckii, Phaeotheca triangularis, Aureobasidium pullulans, and Trimmatostroma salinum), Cladosporium, Aspergillus, and Penicillium species. Most studies on saltern-derived fungi gave attention to black yeasts and their physiological characteristics, including growth under various culture conditions. Since then, biochemical and molecular tools have been employed to explore adaptation of these fungi to salt stress. Genome databases of several fungi in salterns are now publicly available and being used to elucidate salt tolerance mechanisms and discover the target genes for agricultural and industrial applications. Notably, the number of enzymes and novel metabolites known to be produced by diverse saltern-derived fungi has increased significantly. Therefore, fungi in salterns are not only interesting and important subjects to study fungal biodiversity and adaptive mechanisms in extreme environments, but also valuable bioresources with potential for biotechnological applications.


Assuntos
Fungos/fisiologia , Sais/química , Cloreto de Sódio/metabolismo , Solo/química , Adaptação Fisiológica , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Tolerância ao Sal
19.
J Vet Sci ; 20(4): e38, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31364323

RESUMO

Use of a saline chaser has been reported to allow reduction of contrast dose and artifacts during computed tomography (CT) examination in humans. This study assesses the extent of contrast dose by using a saline chaser in abdominal CT scans of normal dogs. Five beagles underwent abdominal CT scans. Three protocols were applied: 600 mg I/kg iohexol without saline chaser (protocol 1), 30% lower dose of iohexol (420 mg I/kg) followed by a 10 mL saline chaser (protocol 2), and 40% lower dose of iohexol (360 mg I/kg) followed by a 10 mL saline chaser (protocol 3). Attenuation values were obtained from aorta, portal vein, and liver parenchyma. The maximum enhancement values (MEVs) in protocol 2 were significantly higher than those in protocols 1 and 3 in the aorta; no difference was seen in the portal vein in all protocols. The liver parenchymal MEVs in protocols 1 and 2 were significantly higher than those obtained in protocol 3. In this study, the use of a saline chaser and a reduced dose of contrast material did not affect vessel enhancement. In conclusion, use of a saline chaser for abdominal CT of dogs is recommended because it allows a 30% reduction of contrast dose without decreasing vascular and hepatic parenchymal enhancement.


Assuntos
Meios de Contraste/análise , Iohexol/análise , Radiografia Abdominal/veterinária , Cloreto de Sódio/administração & dosagem , Tomografia Computadorizada por Raios X/veterinária , Animais , Meios de Contraste/administração & dosagem , Cães , Iohexol/administração & dosagem , Radiografia Abdominal/métodos , Cloreto de Sódio/análise , Tomografia Computadorizada por Raios X/métodos
20.
Lett Appl Microbiol ; 69(4): 230-236, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31381169

RESUMO

This study evaluated the survival responses of Listeria monocytogenes strains (individually and mixed) in a soft lactic cheese following acid and salt stress exposures. The Weibull and log-linear with tail models were used to predict the survival responses of the pathogen in the cheese stored at 4°C for 15 days. Both models showed a good prediction accuracy for stressed L. monocytogenes cells (Af = 1·00) and higher prediction errors (Af = 1·12-1·14) for nonstressed cells. The inactivation rates (δ (d) and kmax (d-1 )) were significantly lower (P < 0·05) for cells subjected to stress exposure indicating the enhanced tolerance to food stress. However, while enhanced tolerance appeared to be the main effect of stress pre-exposure, in one susceptible strain (69), stress exposure led to higher rates of inactivation. When introduced into the food as mixed strains, one strain out-lived others and remained as the sole survivor. Such strains that perhaps have a predilection for the food environment can provide more cautious estimates of kinetic parameters for predicting L. monocytogenes responses in foods especially if their stress-hardened tolerant cells are used. SIGNIFICANCE AND IMPACT OF THE STUDY: The ability to predict the growth and survival of Listeria monocytogenes in contaminated RTE foods is essential for listeriosis risk assessment. The results of this study provided valuable information on the kinetic parameters of survival of some L. monocytogenes strains found within the South African food environment. In addition to showing differences in the survival responses among strains, the study also showed the importance of the pre-contamination state of the cells in influencing survival kinetics.


Assuntos
Queijo/microbiologia , Ácido Láctico/farmacologia , Listeria monocytogenes/crescimento & desenvolvimento , Listeriose/epidemiologia , Cloreto de Sódio/farmacologia , Queijo/análise , Microbiologia de Alimentos , Medição de Risco , Tolerância ao Sal/fisiologia , África do Sul/epidemiologia
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