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1.
Water Environ Res ; 96(8): e11110, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39155465

RESUMO

This study introduces draw solutions for application in forward osmosis (FO) processes, combining mono propylene glycol propyl ether (PGPE) with the cellulose derivative hydroxypropyl cellulose (HPC). A total of 16 unique single-solute and ternary organic draw solutions were prepared and evaluated, leading to the selection of three promising solutions for further investigation. Notably, eight of the initial organic draw solutions demonstrated osmotic pressures exceeding 2.4 MPa. The dynamic viscosities of all draw solutions exhibited a significant reduction with increasing temperature. Among the investigated solutions, the 0.25HPC-3.75PGPE demonstrated the most favorable FO performance, achieving average experimental water fluxes of 11.062 and 9.852 Lm-2 h-1 (LMH) against a 1 g/L NaCl brackish feed solution across two FO runs. PRACTITIONER POINTS: Hydroxypropyl cellulose (HPC, MW ~100,000) was mixed with propylene glycol propyl ether (PGPE) as draw solutes for FO processes. Seven combinations of HPC and PGPE produced osmolalities greater than 1000 mOsm/kg. 0.5HPC-7.5PGPE ternary draw solution achieved experimental water fluxes of 11.062 and 9.852 LMH against 1 g/L NaCl brackish feed solution. Leveraging the LCSTs of these ternary organic solutions holds promise for improved separation and regeneration processes.


Assuntos
Celulose , Osmose , Águas Salinas , Purificação da Água , Celulose/química , Celulose/análogos & derivados , Purificação da Água/métodos , Águas Salinas/química , Propilenoglicóis/química
2.
Chemosphere ; 363: 142899, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39029711

RESUMO

Anaerobically-treated palm oil mill effluent (POME) still has unacceptable properties for water recycling and reuse, with an unpleasant appearance due to the brownish color caused by tannins and phenolic compounds. This study proposes an approach for treating anaerobically-treated POME for water recycling by combining organic precipitation, electrocoagulation (EC), and ion-exchange resin, followed by reverse osmosis (RO) membrane filtration in series. The results indicated that the organic precipitation enhanced the efficiency of EC treatment in reducing the concentrations of tannins, color, and chemical oxygen demand (COD) of the anaerobically-treated POME effluent, with reductions of 95.73%, 96.31%, and 93.96% for tannin, color, and COD, respectively. Moreover, organic precipitation affected the effectiveness of Ca2+ and Mg2+ ion removal using ion exchange resin and RO membrane filtration. Without prior organic precipitation, the ion-exchange resin process required a longer contact time, and the RO membrane filtration treatment was hardly effective in removing total dissolved solids (TDS). The combined process gave a water quality that meets the criteria set by the Thailand Ministry of Industry for industrial boiler use (COD 88 mg/L, TDS <0.001 mg/L, water hardness <5 mg-CaCO3/L, and pH 6.9).


Assuntos
Filtração , Resinas de Troca Iônica , Osmose , Óleo de Palmeira , Eliminação de Resíduos Líquidos , Óleo de Palmeira/química , Filtração/métodos , Resinas de Troca Iônica/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Membranas Artificiais , Purificação da Água/métodos , Eletrocoagulação/métodos , Anaerobiose , Resíduos Industriais/análise , Análise da Demanda Biológica de Oxigênio , Taninos/química , Taninos/análise , Precipitação Química , Águas Residuárias/química
3.
Sci Total Environ ; 945: 174080, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38906281

RESUMO

Reverse osmosis (RO) plays a pivotal role in shale gas wastewater resource utilization. However, managing the reverse osmosis concentrate (ROC) characterized by high salinity and increased concentrations of organic matter is challenging. In this study, we aimed to elucidate the enhancement effects and mechanisms of pre-ozonation on organic matter removal efficacy in ROC using a biological activated carbon (BAC) system. Our findings revealed that during the stable operation phase, the ozonation (O3 and O3/granular activated carbon)-BAC system removes 43.6-72.2 % of dissolved organic carbon, achieving a 4-7 fold increase in efficiency compared with that in the BAC system alone. Through dynamic analysis of influent and effluent water quality, biofilm performance, and microbial community structure, succession, and function prediction, we elucidated the following primary enhancement mechanisms: 1) pre-ozonation significantly enhances the biodegradability of ROC by 4.5-6 times and diminishes the organic load on the BAC system; 2) pre-ozonation facilitates the selective enrichment of microbes capable of degrading organic compounds in the BAC system, thereby enhancing the biodegradation capacity and stability of the microbial community; and 3) pre-ozonation accelerates the regeneration rate of the granular activated carbon adsorption sites. Collectively, our findings provide valuable insights into treating ROC through pre-oxidation combined with biotreatment.


Assuntos
Carvão Vegetal , Osmose , Ozônio , Eliminação de Resíduos Líquidos , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Carvão Vegetal/química , Biodegradação Ambiental , Poluentes Químicos da Água/análise , Gás Natural
4.
Water Res ; 260: 121937, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878313

RESUMO

Reverse osmosis (RO) system has been increasingly applied for circulating cooling water (CCW) reclamation. Plasticizers, which may be dissolved into CCW system in plastic manufacturing industry, cannot be completely removed by the pretreatment prior to RO system, possibly leading to severe membrane biofouling. Deciphering the characteristics and mechanisms of RO membrane biofouling in the presence of trace plasticizers are of paramount importance to the development of effective fouling control strategies. Herein, we demonstrate that exposure to a low concentration (1 - 10 µg/L) of three typical plasticizers (Dibutyl phthalate (DBP), Tributyl phosphate (TBP) and 2,2,4-Trimethylpentane-1,3-diol (TMPD)) detected in pretreated real CCW promoted Escherichia coli biofilm formation. DBP, TBP and TMPD showed the highest stimulation at 5 or 10 µg/L with biomass increasing by 55.7 ± 8.2 %, 35.9 ± 9.5 % and 32.2 ± 14.7 % respectively, relative to the unexposed control. Accordingly, the bacteria upon exposure to trace plasticizers showed enhanced adenosine triphosphate (ATP) activity, stimulated extracellular polymeric substances (EPS) excretion and suppressed intracellular reactive oxygen species (ROS) induction, causing by upregulation of related genes. Long-term study further showed that the RO membranes flowing by the pretreated real CCW in a polypropylene plant exhibited a severer biofouling behavior than exposed control, and DBP and TBP parts played a key role in stimulation effects on bacterial proliferation. Overall, we demonstrate that RO membrane exposure to trace plasticizers in pretreated CCW can upregulate molecular processes and physiologic responses that accelerate membrane biofouling, which provides important implications for biofouling control strategies in membrane-based CCW treatment systems.


Assuntos
Biofilmes , Incrustação Biológica , Escherichia coli , Membranas Artificiais , Osmose , Plastificantes , Purificação da Água , Escherichia coli/efeitos dos fármacos , Biofilmes/efeitos dos fármacos
5.
Environ Sci Pollut Res Int ; 31(27): 39454-39480, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38822176

RESUMO

The forward osmosis (FO) process has recently gained significant interest in treating wastewater, brackish/seawater and concentrating feedstocks for various operations, including desalination. The study investigates the effect of different synthesis conditions of the polyamide-based thin-film composite (TFC) FO membranes on the membranes' final performance. Taguchi statistical analyses were used to fabricate and optimize the polyamide TFC FO membrane. The process parameters as factors were the amount of polyethersulfone (PES), polyethylene glycol 400 (PEG-400), polyvinyl pyrrolidone (PVP), m-phenylenediamine (MPD), and trimesoyl chloride (TMC), and TMC reaction-time (RT). The Taguchi method was adopted to investigate the optimal conditions and the significance of individual factors using an L16 (45) orthogonal array. Another Taguchi analysis (Taguchi 2) was adopted to investigate the influence of other important parameters like optimal conditions for MPD, TMC, and TMC reaction-time factors using an L9 (33) orthogonal array. Confirmation tests validated a maximum water flux of 46.4 ± 2.32 L/m2·h with a specific combination of control factors for membrane synthesis: PES/PEG/PVP/MPD/TMC/TMC RT-16/7/0.5/1/0.05/30. These tests demonstrated a high-water flux of 7.05 ± 0.35 L/m2·h when exposed to industrial wastewater (secondary effluent) as the feed solution (FS) and fertilizer as the draw solution (DS) in the FO process. The R2 values were more than 90%. The experimental validation confirmed the models' predictive ability with different FSs, including industrial wastewater.


Assuntos
Membranas Artificiais , Nylons , Osmose , Águas Residuárias , Purificação da Água , Águas Residuárias/química , Nylons/química , Purificação da Água/métodos , Eliminação de Resíduos Líquidos/métodos , Polímeros/química
6.
Chemosphere ; 356: 141960, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38604517

RESUMO

Pesticides are used in agriculture to protect crops from pathogens, insects, fungi and weeds, but the release of pesticides into surface/groundwater by agriculture runoff and rain has raised serious concerns not only for the environment but also for human health. This study aimed to investigate the impact of surface properties on the performance of seven distinct membrane types utilized in nanofiltration (NF), reverse osmosis (RO) and forward osmosis (FO) processes in eliminating multiple pesticides from spiked water. Out of the membranes tested, two are self-fabricated RO membranes while the rest are commercially available membranes. Our results revealed that the self-fabricated RO membranes performed better than other commercial membranes (e.g., SW30XLE, NF270, Duracid and FO) in rejecting the targeted pesticides by achieving at least 99% rejections regardless of the size of pesticides and their log Kow value. Despite the marginally lower water flux exhibited by the self-fabricated membrane compared to the commercial BW30 membrane, its exceptional ability to reject both mono- and divalent salts renders it more apt for treating water sources containing not only pesticides but also various dissolved ions. The enhanced performance of the self-fabricated RO membrane is mainly attributed to the presence of a hydrophilic interlayer (between the polyamide layer and substrate) and the incorporation of hydrophilic nanosheets in tuning its surface characteristics. The findings of the work provide insight into the importance of membrane surface modification for the application of not only the desalination process but also for the removal of contaminants of emerging concern.


Assuntos
Filtração , Membranas Artificiais , Osmose , Praguicidas , Poluentes Químicos da Água , Purificação da Água , Praguicidas/análise , Praguicidas/química , Praguicidas/isolamento & purificação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Purificação da Água/métodos , Filtração/métodos , Interações Hidrofóbicas e Hidrofílicas
7.
Environ Sci Pollut Res Int ; 31(21): 31123-31134, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38627346

RESUMO

Electrochemical desalination is an effective method for recovering salts from reverse osmosis (RO) brine. However, traditional technologies like bipolar membrane technology often face challenges related to membrane blockage. To overcome this issue, a preparative vertical-flow electrophoresis (PVFE) system was used for the first time to treat RO brine of petrochemical wastewater. In order to optimize the PVFE operation and maximize acids and bases production while minimizing energy consumption, the response surface method was employed. The independent variables selected were the electric field intensity (E) and flow rate (v), while the dependent variables were the acid-base concentration and energy consumption (EC) for acid-base production. Using the central composite design methodology, the operation parameters were optimized to be E = 154.311 V/m and v = 0.83 mL/min. Under these conditions, the base concentrations of the produced bases and acids reached 3183.06 and 2231.63 mg/L, respectively. The corresponding base EC and acid EC were calculated to be 12.57 and 11.62 kW·h/kg. In terms of the acid-base concentration and energy consumption during the PVFE process, the electric field intensity was found to have a greater influence than the flow rate. These findings provide a practical and targeted solution for recycling waste salt resources from RO brine.


Assuntos
Osmose , Águas Residuárias , Águas Residuárias/química , Eletroforese , Eliminação de Resíduos Líquidos/métodos , Sais
8.
Dev Cell ; 59(12): 1553-1570.e7, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38574732

RESUMO

Cells remodel their cytoskeletal networks to adapt to their environment. Here, we analyze the mechanisms utilized by the cell to tailor its microtubule landscape in response to changes in osmolarity that alter macromolecular crowding. By integrating live-cell imaging, ex vivo enzymatic assays, and in vitro reconstitution, we probe the impact of cytoplasmic density on microtubule-associated proteins (MAPs) and tubulin posttranslational modifications (PTMs). We find that human epithelial cells respond to fluctuations in cytoplasmic density by modulating microtubule acetylation, detyrosination, or MAP7 association without differentially affecting polyglutamylation, tyrosination, or MAP4 association. These MAP-PTM combinations alter intracellular cargo transport, enabling the cell to respond to osmotic challenges. We further dissect the molecular mechanisms governing tubulin PTM specification and find that MAP7 promotes acetylation and inhibits detyrosination. Our data identify MAP7 in modulating the tubulin code, resulting in microtubule cytoskeleton remodeling and alteration of intracellular transport as an integrated mechanism of cellular adaptation.


Assuntos
Proteínas Associadas aos Microtúbulos , Microtúbulos , Processamento de Proteína Pós-Traducional , Tubulina (Proteína) , Humanos , Tubulina (Proteína)/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Acetilação , Adaptação Fisiológica , Transporte Biológico , Citoesqueleto/metabolismo , Osmose , Células Epiteliais/metabolismo
9.
Environ Sci Pollut Res Int ; 31(16): 24584-24598, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38448772

RESUMO

Thin-film nanocomposite (TFN) forward osmosis (FO) membranes have attracted significant attention due to their potential for solving global water scarcity problems. In this study, we investigate the impact of titanium oxide (TiO2) and titanium oxide/reduced graphene (TiO2/rGO) additions on the performance of TFN-FO membranes, specifically focusing on water flux and reverse salt diffusion. Membranes with varying concentrations of TiO2 and TiO2/rGO were fabricated as interfacial polymerizing M-phenylenediamine (MPD) and benzenetricarbonyl tricholoride (TMC) monomers with TiO2 and its reduced graphene composites (TiO2/rGO). The TMC solution was supplemented with TiO2 and its reduced graphene composites (TiO2/rGO) to enhance FO performance and reverse solute flux. All MPD/TMC polyamide membranes are characterized using various techniques such as scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle measurements. The results demonstrate that incorporating TiO2/rGO into the membrane thin layer improves water flux and reduces reverse salt diffusion. In contrast to the TFC membrane (10.24 L m-2h-1 and 6.53 g/m2 h), higher water flux and higher reverse solute flux were detected in the case of TiO2and TiO2/rGO-merged TFC skin membranes (18.81 and 24.52 L m-2h-1 and 2.74 and 2.15 g/m2 h, respectively). The effects of TiO2 and TiO2/rGO stacking on the skin membrane and the performance of TiO2 and TiO2/rGO skin membranes have been thoroughly studied. Additionally, being investigated is the impact of draw solution concentration.


Assuntos
Grafite , Nanocompostos , Titânio , Água , Membranas Artificiais , Osmose , Cloreto de Sódio , Cloreto de Sódio na Dieta
10.
Water Res ; 249: 120866, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101050

RESUMO

Reverse Osmosis (RO) membrane filtration is a very common process for treating a wide range of groundwater types including produced water from coal seam gas (coalbed methane) wells. Mineral scaling limits water recovery for RO membranes and costs money in terms of treatment and downtime. Silica scaling can be particularly troublesome as it is often irreversible. Mitigating silica scaling requires an understanding of its occurrence, speciation mechanism and its interdependency with other operation factors. This study uses a range of techniques to show that silica colloids form during later stages of an RO process with very high recovery. This happens at silica concentrations above the solubility that would normally indicate high risk of silica scale. However, instead of scale, colloids preferentially formed which means the process can operate at high recoveries with RO performance maintained by regular cleaning cycles. The concentration of the colloidal silica through the RO stages was measured through the difference in total and dissolved silica. Once the existence was established with this technique, the particles were trapped and their size, morphology and composition were investigated with Scanning Electron Microscopy (SEM) in conjunction with Energy Dispersive X-Ray Spectroscopy (EDS). This revealed the particles to be predominantly silica with limited other elements involved.


Assuntos
Purificação da Água , Água , Água/química , Dióxido de Silício/química , Purificação da Água/métodos , Osmose , Filtração/métodos , Coloides , Carvão Mineral , Membranas Artificiais
11.
Environ Pollut ; 343: 123271, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38160769

RESUMO

In order to utilize waste heat such as exhaust steam and hot air passing through air preheater in the waste incineration plant to heat air used for evaporating leachate concentrate (LC) by gas-liquid contact evaporation technology, hot air of 600 °C, 450 °C and 250 °C was used to evaporate LC in a laboratory-scale evaporator to obtain purified condensate used for supplying water for circulating cooling water system. The influence of pH, hot air temperature and evaporation rate on COD and NH3-N in condensate were investigated to identify the optimum operation of this technology. The results showed that COD concentration in condensate obviously decreased with increase in hot air temperature. Higher hot air temperature led to higher initial evaporation temperature, and evaporation rate of water was significantly greater than that of small molecular organic matter with lower boiling point than water with increasing hot air temperature. Reduction in contents of phenol, ketone and benzene was responsible for COD decreasing in condensate. COD in condensate decreased with increase in pH, as the amount of volatile organic matter such as fatty acids escaped from LC to condensate decreased. The pH had little influence on the DOM in condensate according to EEM spectra analysis. Evaporation rate had little influence on COD in the condensate water. NH3-N concentrations in condensate in all experimental groups were far away from the limit value (10 mg/L) in the water quality standard. Under the premise of meeting water quality standard, the lowest temperature (450 °C) of hot air was selected to save energy and use lower grade waste heat. Therefore, the optimum condition was 450 °C of hot air, pH = 7 of LC and CF = 10. At this condition, molecular weight of DOM in the condensate was smaller and humification degree and aromaticity of DOM were lower according to UV-visible absorption spectrum analysis.


Assuntos
Incineração , Poluentes Químicos da Água , Filtração , Reatores Biológicos , Temperatura Alta , Osmose , Poluentes Químicos da Água/análise
12.
Bioresour Technol ; 394: 130215, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38122995

RESUMO

The treatment of reverse osmosis concentrate generated from urban industrial sewage for resource recovery has been hot. In this research, a biofilm reactor was constructed by combining sycamore deciduous biochar, shell powder, and polyurethane sponge loaded with Zobellella denitrificans sp. LX16. For ammonia nitrogen (NH4+-N), calcium (Ca2+), chemical oxygen demand (COD), cadmium (Cd2+), and tetracycline (TC), the removal efficiencies were 98.69 %, 83.95 %, 97.26 %, 98.34 %, and 69.12 % at a hydraulic retention time (HRT) of 4 h, pH of 7.0, and influent salinity, Ca2+, and TC concentrations of 1.0, 180.0, and 3.0 mg/L, respectively. The biofilm reactor packing has a three-dimensional structure to ensure good loading of microorganisms while promoting electron transfer and metabolic activity of microorganisms and increasing the pollutant tolerance and removal efficiency. The reactor provides a practical reference for the sedimentation of reverse osmosis concentrate to remove Cd2+ and TC by microbial induced calcium precipitation (MICP).


Assuntos
Carvão Vegetal , Compostos Heterocíclicos , Águas Residuárias , Cádmio , Eliminação de Resíduos Líquidos/métodos , Cálcio , Poliuretanos , Pós , Desnitrificação , Tetraciclina , Antibacterianos , Biofilmes , Osmose , Reatores Biológicos , Nitrogênio/metabolismo , Nitrificação
13.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 57(3): e166205, 2020. tab, graf
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1122181

RESUMO

In freshwater fish with external fertilization, sperm sampling can be contaminated with urine, which triggers motility and gives rise to decreased fertilization success. The maintenance of freshwater fish in hyperosmotic conditions may reduce urine production and improve sperm quality. Thus, the aim of this work was to verify if acute exposure to various NaCl concentrations improves sperm quality in the yellowtail tetra Astyanax altiparanae. Spermiation was induced using a single dose of carp pituitary gland (5 mg kg-1) and the males were maintained at various NaCl concentrations: NaCl 0.00% (control), NaCl 0.45% (hypoosmotic), NaCl 0.9% (isosmotic) and NaCl 1.0% (hyperosmotic) for 6 h at 26 °C. Sperm was collected and verified for activation by urine and motility traits. At 0.00%, 0.45%, and 0.90%, the sperm was motile just after sampling, indicating activation by urine. Surprisingly, at hyperosmotic conditions, no activation was observed. Other sperm and motility parameters did not show any statistical differences, including sperm viability (P = 0.7083), concentration (P = 0.9030), total motility (P = 0.6149), VCL (curvilinear velocity; P = 0.1216), VAP (average path velocity; P = 0.1231) and VSL (straight-line velocity; P = 0.1340). Our results indicate that acute maintenance at hyperosmotic conditions eliminates sperm activation by urine and maintains sperm quality. Such a new procedure is interesting for both basic and applied sciences, including reproductive practice in fish.(AU)


Em peixes de água doce com fertilização externa, a amostragem de espermatozoides pode ser contaminada pela urina, o que desencadeia motilidade e gera menor sucesso na fertilização. A manutenção de peixes de água doce em condições hiperosmóticas pode reduzir a produção de urina e melhorar a qualidade do esperma. Assim, o presente trabalho foi delineado para verificar se a exposição aguda a várias concentrações de NaCl melhora a qualidade do esperma no tetra-amarelo Astyanax altiparanae. A espermiação foi induzida usando uma dose única de hipófise da carpa (5 mg kg-1) e os machos foram mantidos em várias concentrações de NaCl: NaCl 0,00% (controle), NaCl 0,45% (hipoosmótico), NaCl 0,9% (isosmótico) e NaCl 1,0% (hiperosmótico) por seis horas a 26 °C. O esperma foi colhido e verificado quanto à ativação por urina e traços de motilidade. Em 0,00%, 0,45%, 0,90% os espermatozóides eram móveis logo após a amostragem, indicando ativação pela urina. Surpreendentemente, em condições hiperosmóticas, nenhuma ativação foi observada. Outros parâmetros espermáticos e de motilidade não mostraram diferenças estatísticas, incluindo viabilidade espermática (P = 0,7083), concentração (P = 0,9030), motilidade total (P = 0,6149), VCL (Velocidade Curvilinear; P = 0,1216), VMD (Velocidade Média de Deslocamento; P = 0,1230) e VLR (Velocidade em linha Reta; P = 0,1340). Nossos resultados indicam que a manutenção aguda em condições hiperosmóticas elimina a ativação do esperma pela urina e mantém a qualidade do esperma. Esse novo procedimento é interessante para as ciências básicas e aplicadas, incluindo a prática reprodutiva em peixes.(AU)


Assuntos
Animais , Osmose , Salinidade , Análise do Sêmen/métodos , Análise do Sêmen/veterinária , Characidae/fisiologia , Motilidade dos Espermatozoides
14.
Electron. j. biotechnol ; 39: 67-73, may. 2019. graf, tab
Artigo em Inglês | LILACS | ID: biblio-1052039

RESUMO

BACKGROUND: The supplementation of betaine, an osmoprotective compatible solute, in the cultivation media has been widely used to protect bacterial cells. To explore the effects of betaine addition on industrial fermentation, Escherichia coli THRD, an L-threonine producer, was used to examine the production of L-threonine with betaine supplementation and the underlying mechanism through which betaine functions was investigated. RESULTS: Betaine supplementation in the medium of E. coli THRD significantly improved L-threonine fermentation parameters. The transcription of zwf and corresponding enzyme activity of glucose-6-phosphate dehydrogenase were significantly promoted by betaine addition, which contributed to an enhanced expression of zwf that provided more nicotinamide adenine dinucleotide phosphate (NADPH) for L-threonine synthesis. In addition, as a result of the betaine addition, the betaine-stimulated expression of enhanced green fluorescent protein (eGFP) under the zwf promoter within a plasmid-based cassette proved to be a transcription-level response of zwf. Finally, the promoter of the phosphoenolpyruvate carboxylase gene ppc in THRD was replaced with that of zwf, while L-threonine fermentation of the new strain was promoted by betaine addition. Conclusions: We reveal a novel mode of betaine that facilitates the microbial production of useful compounds. Betaine supplementation upregulates the expression of zwf and increases the NADPH synthesis, which may be beneficial for the cell growth and thereby promote the production of L-threonine. This finding might be useful for the production of NADPH-dependent amino acids and derivatives in E. coli THRD or other E. coli strains.


Assuntos
Treonina/metabolismo , Betaína/metabolismo , Escherichia coli/metabolismo , Osmose , Via de Pentose Fosfato , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Escherichia coli/enzimologia , Fermentação , Glucosefosfato Desidrogenase/metabolismo , NADP
15.
Acta amaz ; 44(1): 153-156, 2014. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455168

RESUMO

The important chemical and food properties conferred to P. angulata make it necessary to conduct studies in seed conservation. This study evaluated the effect of priming of P. angulata seed for varying periods and storage conditions. Lots of seeds were stored in a refrigerator and in ambient conditions for up to 24 months. Some of these seeds were primed before or after storage. The results show that there was variation in moisture content. The germination rate and germination rate index remained high in ambient conditions when primed up to 24 months.


As importantes propriedades alimentícias e químicas atribuídas a P. angulata fazem dela uma espécie de grande valor para estudos de conservação de sementes. Este trabalho objetivou avaliar o efeito do pré-condicionamento osmótico de sementes de P. angulata submetidas a diferentes condições e períodos de armazenamento. Lotes de sementes foram armazenados em condições de ambiente e refrigerador até 24 meses. Parte dessas sementes foram osmocondicionadas antes ou após o armazenamento. Os resultados apresentados mostram que houve variação no teor de umidade. As sementes mantiveram taxas de germinação e índice de velocidade de germinação elevadas em ambiente quando osmocondicionadas até 24 meses.


Assuntos
Germinação , Longevidade , Physalis , Osmose , Sementes/crescimento & desenvolvimento
16.
Gastroenterol. latinoam ; 24(supl.1): S20-S24, 2013. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-763714

RESUMO

Constipation should be defined by symptoms, and is refractory to fiber in about 40 percent of the cases. About 50 percent of these cases caused by a defecatory disorder, usually dyssynergic defecation, which is defined as inadequate relaxation of the pelvic floor during straining. In this cases, biofeedback therapy produces an adequate relief in about 80 percent. It is suggested that ano-rectal manometry with balloon expulsion test should be the first approach in cases of fiber-refractory constipation. In cases of normal ano-rectal test, an evaluation of colonic transit time is suggested. In cases of slow transit constipation, treatment responses are much lower. Osmotic laxatives, especially polyethilenglicol, are recommended in all types of constipation. There are new laxatives, like lubiprostone and linaclotide, and new prokinetics, like prucalopride, that are already available in different countries, that show a reasonable good response profile.


La constipación debe ser definida por síntomas, y es refractaria al uso de fibra en alrededor de 4 por ciento de los casos. En alrededor de 50 por ciento existe un defecto expulsivo, casi siempre defecación disinérgica, la que es definida por una relajación inadecuada del piso pelviano al momento de pujar. Se recomienda un estudio de manometría ano-rectal con test de expulsión del balón como primera opción en estos casos. En los casos de disinergia, la terapia con biofeedback tiene una eficacia del alrededor de 80 por ciento, beneficio que se mantiene a largo plazo. En casos de manometría ano-rectal normal, se sugiere evaluar un tiempo de transito colónico, pues la respuesta de los casos con tránsito lento es bastante menor. En todos los casos de constipación se recomienda el uso de laxantes osmóticos tipo polietilenglicol. Existen nuevos laxantes, como lubiprostona y linaclotide, y nuevos procinéticos como prucalopride, que ya están disponibles en diversos países del mundo, que tienen una eficacia razonable en estos casos.


Assuntos
Humanos , Constipação Intestinal/terapia , Retroalimentação Fisiológica , Laxantes/uso terapêutico , Polietilenoglicóis/uso terapêutico , Constipação Intestinal/diagnóstico , Constipação Intestinal/fisiopatologia , Manometria/métodos , Osmose
17.
Arch. latinoam. nutr ; 62(4): 363-369, dic. 2012. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-714890

RESUMO

Las frutas son consideradas fuentes de compuestos antioxidantes, cuyas propiedades pudieran desmejorar debido al procesamiento. El objetivo de esta investigación fue determinar el efecto del escaldado y la deshidratación osmótica sobre el contenido de polifenoles totales, taninos y la capacidad antioxidante de la ciruela criolla (Prunus domestica) en sus variedades amarilla y roja. La concentración de los polifenoles totales se determinó mediante el método Folin-Ciocalteu, los taninos por el método de la vanilina y la capacidad antioxidante por la eficiencia antirradical (EA) y el método de poder reductor férrico (FRP). El contenido de polifenoles totales y los taninos fueron mayores en la ciruela roja que en la amarilla. En las dos variedades, el mayor contenido de polifenoles se encontró en la pulpa, mientras que los taninos se encontraron en mayor proporción en las cáscaras. La ciruela roja presentó mayor capacidad antioxidante, siendo la EA baja y de cinética lenta para las dos variedades. Se observó una correlación lineal entre los polifenoles y los taninos con la eficiencia antirradical, sin embargo, con el poder reductor no hubo correlación. El escaldado incrementó el contenido de polifenoles, mientras que los taninos y la EA disminuyeron, el poder reductor no se vio afectado por los tratamientos. Para la deshidratación osmótica se obtuvo una disminución significativa de los taninos y la eficiencia antirradical, mientras que los polifenoles y el poder reductor no se vieron afectados por el procesamiento. Se recomienda el escaldado como alternativa de consumo y conservación en la ciruela criolla.


Effect of processing on the antioxidant capacity of the plum (Prunus domestica). Fruits are considered sources of antioxidant compounds whose properties could impair due to processing. The objective of this work was to determine the effect of blanching and osmotic dehydration on the total polyphenols content, tannins and antioxidant capacity of plums (Prunus domestica) in yellow and red varieties. The total phenolic content in plums was determined according to the Folin-Ciocalteu assay and tannins were determined by vanillin assay. The antiradical efficiency (AE) and ferric reducing power (FRP) were used to estimate the total antioxidant capacity. The content of total polyphenols and tannins were higher in the red plum. The content of polyphenols in the pulp was higher that the peel while for tannins the opposite was observed in both varieties. The red plum had higher antioxidant capacity. The AE was low and slow kinetics for the two varieties. There was a linear correlation between polyphenols and tannins with antiradical efficiency; however, there was no correlation with the reducing power. The total polyphenols content was increased with blanching, while the tannins and the AE decreased, ferric reducing power is unaffected. For osmotic dehydration, the tannins and the AE were decreased, while the total polyphenols content and ferric reducing power are unaffected.It is recommended the blanched as an alternative to consumption and conservation in the plum.


Assuntos
Antioxidantes/análise , Manipulação de Alimentos/métodos , Frutas/química , Fenóis/análise , Prunus/química , Taninos/análise , Dessecação/métodos , Osmose
18.
Electron. j. biotechnol ; 14(3): 3-3, May 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-602980

RESUMO

Increasing scarcity of irrigation water is a major threat to sustainable production of cotton (Gossypium hirsutum L.). Identifying genomic regions contributing to abiotic stress tolerance will help develop cotton cultivars suitable for water-limited regions through molecular marker-assisted breeding. A molecular mapping F2 population was derived from an intraspecific cross of the drought sensitive G. hirsutum cv. FH-901 and drought tolerant G. hirsutum cv. RH-510. Field data were recorded on physiological traits (osmotic potential and osmotic adjustment); yield and its component traits (seedcotton yield, number of bolls/plant and boll weight); and plant architecture traits (plant height and number of nodes per plant) for F2, F2:3 and F2:4 generations under well-watered versus water-limited growth conditions. The two parents were surveyed for polymorphism using 6500 SSR primer pairs. Joinmap3.0 software was used to construct linkage map with 64 polymorphic markers and it resulted into 35 markers mapped on 12 linkage groups. QTL analysis was performed by composite interval mapping (CIM) using QTL Cartographer2.5 software. In total, 7 QTLs (osmotic potential 2, osmotic adjustment 1, seedcotton yield 1, number of bolls/plant 1, boll weight 1 and plant height 1) were identified. There were three QTLs (qtlOP-2, qtlOA-1, and qtlPH-1) detected only in water-limited conditions. Two QTLs (qtlSC-1 and qtlBW-1) were detected for relative values. Two QTLs (qtlOP-1 and qtlBN-1) were detected for well-watered treatment. Significant QTLs detected in this study can be employed in MAS for molecular breeding programs aiming at developing drought tolerant cotton cultivars.


Assuntos
Secas , Gossypium/fisiologia , Gossypium/genética , Locos de Características Quantitativas , Adaptação Fisiológica , DNA de Plantas/genética , Variação Genética , Gossypium/crescimento & desenvolvimento , Mapeamento Cromossômico/métodos , Osmose , Polimorfismo Genético , Software
19.
Braz. dent. j ; 22(5): 355-358, 2011. tab
Artigo em Inglês | LILACS | ID: lil-601833

RESUMO

The aim of this study was to evaluate in vitro fluoride (F) release from 4 restorative materials (3M ESPE): Ketak Molar Easymix [KME - conventional glass ionomer cement (GIC)]; Rely-X luting 2 [RL2 - resin-modified GIC (RMGIC)]; Vitremer (VIT- RMGIC); and Filtek Z250 [Z250 - negative control]. Disc-shaped specimens were fabricated according to the manufacturer’s instructions and placed into 10 mL of reverse osmosis water at 37°C until the analyses were done using a liquid membrane for selective F ion electrode (Orion 710). F release was evaluated every 6 h in the first day and thereafter daily during 28 days (d). The results were analyzed statistically by two-way ANOVA and Tukey’s test (α=0.05). Mean F release and standard deviation values (in ppm) were: KME: 6 h- 0.34 ± 0.04; 24 h- 1.22 ± 0.30; 7 d- 0.29 ± 0.09; 14 d- 0.20 ± 0.04; 28 d- 0.16 ± 0.01; RL2: 6 h- 2.46 ± 0.48; 24 h-12.33 ± 2.93; 7 d- 1.37 ± 0.38; 14 d- 0.80 ± 0.13; 28 d- 0.80 ± 0.21; VIT: 6 h- 0.98 ± 0.35; 24 h- 4.35 ± 1.22; 7 d- 0.66 ± 0.23; 14 d- 0.40 ± 0.07; 28 d- 0.39 ± 0.08; Z250: 6 h- 0.029 ± 0.001; 24 h- 0.024 ± 0.009; 7 d- 0.023 ± 0.004; 14 d- 0.025 ± 0.001; 28 d- 0.028 ± 0.001. RL2 RMGIC released more F than the other materials in all periods. The greatest release of F occurred in the first 24 h.


O objetivo deste estudo foi avaliar, in vitro, a liberação de flúor (F) de 4 materiais restauradores (3M-ESPE): KME cimento de ionômero de vidro convencional (CIV) (Ketak Molar Easymix); RX2- GIC modificado por resina (RMGIC) (Rely-X luting 2); VIT-RMGIC (Vitremer); -resina composta Z250 (controle negativo) (Filtek Z250). As amostras foram confeccionadas de acordo com as instruções do fabricante e colocadas em 10 mL de água destilada 37°C até as leituras, que foram feitas utilizando um eletrodo de íon seletivo de fluoreto de membrana líquida (Orion 710). A liberação de flúor foi avaliada a cada 6 h no primeiro dia e, diariamente durante 28 dias (d). Os resultados foram analisados estatisticamente usando ANOVA a dois critérios e teste de Tukey. A média e desvio padrão de liberação de F, valores (em ppm) foram: KME: 6 h- 0,34 ± 0,04; 24 h- 1,22 ± 0,30; 7 d- 0,29 ± 0,09; 14 d- 0,20 ± 0,04; 28 d- 0,16 ± 0,01; RL2: 6 h- 2,46 ± 0,48; 24 h- 12,33 ± 2,93; 7 d- 1,37 ± 0,38; 14 d- 0,80 ± 0,13; 28 d- 0,80 ± 0,21; VIT: 6 h- 0,98 ± 0,35; 24 h- 4,35 ± 1,22; 7 d- 0,66 ± 0,23; 14 d- 0,40 ± 0,07; 28 d- 0,39 ± 0,08; Z250: 6 h- 0,029 ± 0,001; 24 h- 0,024 ± 0,009; 7 d- 0,023 ± 0,004; 14 d- 0,025 ± 0,001; 28 d- 0,028 ± 0,001. Concluiu-se que RL2 liberou mais F do que os outros materiais em todos os períodos. A maior liberação de F ocorreu nas primeiras 24 h.


Assuntos
Humanos , Cariostáticos/química , Materiais Dentários/química , Fluoretos/química , Resinas Compostas/química , Difusão , Cimentos de Ionômeros de Vidro/química , Eletrodos Seletivos de Íons , Teste de Materiais , Osmose , Potenciometria/instrumentação , Cimentos de Resina/química , Temperatura , Fatores de Tempo , Água/química
20.
Vitae (Medellín) ; 17(2): 121-127, mayo-ago. 2010.
Artigo em Espanhol | LILACS | ID: lil-557507

RESUMO

La liofilización es una alternativa de interés como método de conservación de alimentos, la cual permite prolongar el tiempo de vida útil manteniendo significativamente las propiedades físicas y fisicoquímicas relacionadas con su calidad. El objetivo de este trabajo fue evaluar el efecto de la liofilización y la osmoliofilización sobre las cinéticas de congelación y de secado, la actividad de agua, el volumen, la porosidad y la capacidad de rehidratación en rodajas de pitahaya amarilla (Selenicereus megalanthus). Como pretratamiento osmótico a la liofilización (osmoliofilización), las rodajas se sumergieron en una solución de sacarosa con 55 ºBrix a 25ºC; se congelaron a -35°C, la sublimación se llevó a presión de vacío de 8 Pa y el secado se realizó desde -35 hasta 35°C. Los resultados de los tratamientos evidenciaron, al final del proceso, diferencias significativas en la porosidad, volumen y capacidad de rehidratación (que fueron mayores para el tratamiento liofilizado), mientras que la cinética de secado y la actividad de agua no presentaron diferencias significativas. El tratamiento de liofilización fue adecuado para la conservación de rodajas de pitahaya amarilla, ya que permitió reducir la actividad de agua por debajo de 0,4; conservó significativamente el volumen y presentó alta capacidad de rehidratación.


Freeze-drying is an interesting alternative as a food preservation method allowing to extend the shelf life and significantly preserving physical and physicochemical properties related to quality. The objective of this study was to evaluate the effect of freeze-drying and osmo-freeze-drying on the kinetics of freezing and drying, water activity, volume, porosity and rehydration capacity of sliced yellow pitahaya (Selenicereus megalanthus). As osmotic pretreatment to freeze-drying (osmo-freeze-drying), slices were immersed in a sucrose solution at 55°Brix. The slices were frozen at -35°C. The sublimation was carried at vacuum pressure of 8 Pa and drying was carried out from -35 to 35°C. The results of these treatments at the end of the process showed significant differences in porosity, volume and rehydration capacity (being higher for freeze-drying treatment), while the kinetics of drying and water activity were not significant. The freeze drying treatment was suitable for the preservation of sliced yellow pitahaya, because it helped to decrease water activity below 0.4, preserved and showed significant volumes of high rehydration capacity.


Assuntos
Cactaceae , Conservação de Alimentos , Desidratação , Liofilização , Osmose
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