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1.
Food Chem ; 462: 140991, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39208721

RESUMO

Shewanella baltica is a specific spoilage organism of golden pomfret. This study aims to explore the antibacterial mechanism of slightly acidic electrolysed water (SAEW) against S. baltica (strains ABa4, ABe2 and BBe1) in golden pomfret broths by metabolomics, proteomics and bioinformatics analyses. S. baltica was decreased by at least 3.94 log CFU/mL after SAEW treatment, and strain ABa4 had the highest resistance. Under SAEW stress, amino acids and organic acids in S. baltica decreased, and nucleotide related compounds degraded. Furthermore, 100 differentially expressed proteins (DEPs) were identified. Most DEPs of strains ABe2 and BBe1 were down-regulated, while some DEPs of strain ABa4 were up-regulated, especially those oxidative stress related proteins. These results suggest that the modes of SAEW against S. baltica can be traced to the inhibition of amino acid, carbon, nucleotide and sulphur metabolisms, and the loss of functional proteins for temperature regulation, translation, motility and protein folding.


Assuntos
Proteínas de Bactérias , Shewanella , Shewanella/metabolismo , Shewanella/química , Shewanella/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Água/metabolismo , Água/química , Eletrólise , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Antibacterianos/química , Concentração de Íons de Hidrogênio , Vigna/química , Vigna/microbiologia , Vigna/metabolismo
2.
Food Chem ; 462: 140994, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39208729

RESUMO

The quality of meat in prepared dishes deteriorates due to excessive protein denaturation resulting from precooking, freezing, and recooking. This study aimed to link the precooked state with chicken breast's recooked quality. Cooked Value (CV), based on protein denaturation kinetics, was established to indicate the doneness of meat during pre-heating. The effects of CVs after pre-heating on recooked qualities were investigated compared to fully pre-heated samples (control). Mild pre-heating reduced water migration and loss. While full pre-heating inhibited protein oxidation during freezing, intense oxidation during pre-heating led to higher oxidation levels. Surface hydrophobicity analysis revealed that mild pre-heating suppressed aggregation during recooking. These factors contributed to a better texture and microstructure of prepared meat with mild pre-heating. Finally, a potential mechanism of how pre-heating affects final qualities was depicted. This study underlines the need for finely controlling the industrial precooking process to regulate the quality of prepared meat.


Assuntos
Galinhas , Culinária , Temperatura Alta , Carne , Oxirredução , Desnaturação Proteica , Água , Animais , Cinética , Carne/análise , Água/química , Interações Hidrofóbicas e Hidrofílicas
3.
Food Chem ; 462: 141025, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39213966

RESUMO

This study aimed to assess the suitability of Chachafruto flour (CHF) as a stabilizing agent for an oil-in-water emulsion and its impact on the physicochemical properties of the emulsion after spray drying. Emulsions with varying CHF concentrations (2 %, 3 %, and 4 %) were prepared and compared to a control. The results from the creaming index and particle size (emulsion) analyses indicated that the highest emulsion stability was achieved with 4 %CHF, attributed to its protein content (20.5 %). The encapsulates exhibited spherical and rough surface morphologies but without holes on the surface. Low moisture content (MC < 5 %) and water activity (aw < 0.2) were associated with powder stability. The encapsulates added with CHF showed good reconstitution properties. FTIR confirmed the absence of chemical interactions during the encapsulation process, contributing to the stability. Furthermore, the addition of CHF improved the thermal stability of the encapsulates. This study represents the first investigation on the emulsifying potential of Chachafruto flour.


Assuntos
Cápsulas , Emulsões , Farinha , Tamanho da Partícula , Água , Emulsões/química , Farinha/análise , Cápsulas/química , Água/química , Secagem por Atomização , Óleos/química
4.
Food Chem ; 462: 141028, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39217743

RESUMO

High-moisture extrusion technique with the advantage of high efficiency and low energy consumption is a promising strategy for processing Antarctic krill meat. Consequently, this study aimed to prepare high-moisture textured Antarctic krill meat (HMTAKM) with a rich fiber structure at different water contents (53 %, 57 %, and 61 %) and to reveal the binding and distribution regularity of water molecules, which is closely related to the fiber structure of HMTAKM and has been less studied. The hydrogen-bond network results indicated the presence of at least two or more types of water molecules with different hydrogen bonds. Increasing the water content of HMTAKM promoted the formation of hydrogen bonds between the water molecules and protein molecules, leading to the transition of the ß-sheet to the α-helix. These findings offer a novel viable processing technique for Antarctic krill and a new understanding of the fiber formation of high-moisture textured proteins.


Assuntos
Euphausiacea , Ligação de Hidrogênio , Água , Euphausiacea/química , Animais , Água/química , Água/metabolismo , Regiões Antárticas , Carne/análise , Manipulação de Alimentos
5.
Food Chem ; 462: 141012, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39217747

RESUMO

To investigate the variation and fractionation of stable isotopes from irrigation water to soil, grapes, and wine, δ2H, δ18O, and δ17O in different samples from 10 regions in China were determined using a water isotope analyser. The values were significantly different among regions according to the chemometric analysis. All isotopes were significantly and positively correlated with irrigation water-soil and grape-wine. A significant water isotopic fractionation effect was observed from the irrigation water to the soil, grapes, and wine. Stable isotope distribution characteristics correlated with longitude, latitude, altitude, temperature, precipitation, station pressure and wind speed. The linear discriminant analysis (LDA), random forest (RF), support vector machine (SVM), and feed-forward neural network (FNN) models 58.33-100 %, 80-100 %, 53.33-100 %, and 73.33-100 % accurate for distinguishing the geographical origins of all samples from training and test data, respectively. These findings provide a theoretical basis for authenticating the geographic origin of Chinese wines using stable isotope analysis.


Assuntos
Irrigação Agrícola , Isótopos de Oxigênio , Solo , Vitis , Vinho , Vinho/análise , Vitis/química , Vitis/classificação , Vitis/crescimento & desenvolvimento , Solo/química , Isótopos de Oxigênio/análise , China , Água/análise , Água/química , Deutério/análise , Análise Discriminante , Geografia , Fracionamento Químico
6.
Food Chem ; 462: 140987, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39217748

RESUMO

This study aimed to investigate the textural changes of cooked germinated brown rice (GBR) during freeze-thaw treatment and propose a strategy for enhancing its texture using magnetic field (MF). Seven freeze-thaw cycles exhibited more pronounced effects compared to 7 days of freezing, resulting in increases in GBR hardness by 85.59 %-164.36 % and decreases in stickiness by 10.34 %-43.55 %. Water loss, structural damage of GBR flour, and starch retrogradation contributed to the deterioration of texture. MF mitigated these effects by inhibiting the transformation of bound water into free water, reducing water loss by 0.39 %-0.57 %, and shortening the phase transition period by 2.0-21.5 min, thereby diminishing structural damage to GBR flour and hindering starch retrogradation. Following MF treatment (5 mT), GBR hardness decreased by 21.00 %, while stickiness increased by 45.71 %. This study elucidates the mechanisms through which MF enhances the texture, offering theoretical insights for the industrial production of high-quality frozen rice products.


Assuntos
Culinária , Congelamento , Germinação , Campos Magnéticos , Oryza , Oryza/química , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Farinha/análise , Amido/química , Amido/metabolismo , Água/química , Dureza , Manipulação de Alimentos , Sementes/química , Sementes/crescimento & desenvolvimento
7.
J Environ Sci (China) ; 149: 200-208, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181634

RESUMO

The acidity of atmospheric aerosols influences fundamental physicochemical processes that affect climate and human health. We recently developed a novel and facile water-probe-based method for directly measuring of the pH for micrometer-size droplets, providing a promising technique to better understand aerosol acidity in the atmosphere. The complex chemical composition of fine particles in the ambient air, however, poses certain challenges to using a water-probe for pH measurement, including interference from interactions between compositions and the influence of similar compositions on water structure. To explore the universality of our method, it was employed to measure the pH of ammonium, nitrate, carbonate, sulfate, and chloride particles. The pH of particles covering a broad range (0-14) were accurately determined, thereby demonstrating that our method can be generally applied, even to alkaline particles. Furthermore, a standard spectral library was developed by integrating the standard spectra of common hydrated ions extracted through the water-probe. The library can be employed to identify particle composition and overcome the spectral overlap problem resulting from similar effects. Using the spectral library, all ions were identified and their concentrations were determined, in turn allowing successful pH measurement of multicomponent (ammonium-sulfate-nitrate-chloride) particles. Insights into the synergistic effect of Cl-, NO3-, and NH4+ depletion obtained with our approach revealed the interplay between pH and volatile partitioning. Given the ubiquity of component partitioning and pH variation in particles, the water probe may provide a new perspective on the underlying mechanisms of aerosol aging and aerosol-cloud interaction.


Assuntos
Aerossóis , Monitoramento Ambiental , Análise Espectral Raman , Água , Concentração de Íons de Hidrogênio , Análise Espectral Raman/métodos , Água/química , Monitoramento Ambiental/métodos , Aerossóis/análise , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/química , Atmosfera/química , Material Particulado/análise
8.
J Environ Sci (China) ; 148: 57-68, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095190

RESUMO

The expandable graphite (EG) modified TiO2 nanocomposites were prepared by the high shear method using the TiO2 nanoparticles (NPs) and EG as precursors, in which the amount of EG doped in TiO2 was 10 wt.%. Followed by the impregnation method, adjusting the pH of the solution to 10, and using the electrostatic adsorption to achieve spatial confinement, the Pt elements were mainly distributed on the exposed TiO2, thus generating the Pt/10EG-TiO2-10 catalyst. The best CO oxidation activity with the excellent resistance to H2O and SO2 was obtained over the Pt/10EG-TiO2-10 catalyst: CO conversion after 36 hr of the reaction was ca. 85% under the harsh condition of 10 vol.% H2O and 100 ppm SO2 at a high gaseous hourly space velocity (GHSV) of 400,000 hr-1. Physicochemical properties of the catalysts were characterized by various techniques. The results showed that the electrostatic adsorption, which riveted the Pt elements mainly on the exposed TiO2 of the support surface, reduced the dispersion of Pt NPs on EG and achieved the effective dispersion of Pt NPs, hence significantly improving CO oxidation activity over the Pt/10EG-TiO2-10 catalyst. The 10 wt.% EG doped in TiO2 caused the TiO2 support to form a more hydrophobic surface, which reduced the adsorption of H2O and SO2 on the catalyst, greatly inhibited deposition of the TiOSO4 and formation of the PtSO4 species as well as suppressed the oxidation of SO2, thus resulting in an improvement in the resistance to H2O and SO2 of the Pt/10EG-TiO2-10 catalyst.


Assuntos
Grafite , Oxirredução , Platina , Dióxido de Enxofre , Titânio , Titânio/química , Grafite/química , Dióxido de Enxofre/química , Platina/química , Catálise , Monóxido de Carbono/química , Água/química , Poluentes Atmosféricos/química , Modelos Químicos
9.
J Acoust Soc Am ; 156(4): 2077-2087, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352249

RESUMO

Small vessels (<10 m) radiate underwater noise in sensitive coastal environments, but there is insufficient knowledge of their noise radiation. Through detailed measurements of seven small boats and a jet ski in a shallow water environment on the Swedish west coast, this study presents results on the speed dependence of small vessel underwater noise, its sources, and its directivity. For vessels with planing hulls, broadband source levels increase with speed until planing is attained. When planing, source level dependence on speed is weak. A detailed noise source analysis of one vessel showed that at low speed, tonals from the engine dominate the noise radiation, whereas at higher speeds, propeller tonals and broadband noise dominate. Noise radiation into different horizontal angles shows little angle dependence, and noise levels relative to the closest point of approach show a similar pattern across all investigated vessels. Received noise levels at approximately 100 m range are not high enough to cause hearing impairment in marine animals, but fast-moving small vessels may cause behavioural reactions or stress responses across several marine animal groups.


Assuntos
Acústica , Movimento (Física) , Ruído dos Transportes , Navios , Ruído dos Transportes/efeitos adversos , Espectrografia do Som , Fatores de Tempo , Água , Ruído/efeitos adversos , Oceanos e Mares , Processamento de Sinais Assistido por Computador , Suécia , Animais
10.
Ecol Lett ; 27(9): e14508, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39354903

RESUMO

A self-reinforcing positive feedback is regarded as a critical process for maintaining alternative stable states (ASS); however, identification of ASS and quantification of positive feedbacks remain elusive in natural ecosystems. Here, we used large-scale field surveys to search for ASS and a positive feedback mechanism under a wide range of habitats on the Tibetan Plateau. Using multiple methods, we proved that three stable states exist that accompany alpine marsh degradation. Positive feedbacks between changing soil moisture and plant community composition forced the ecosystem into another stable state, and the alteration of water use efficiency (WUE) of the component species contributed to this shift. This study provides the first empirical evidence that positive feedback loops maintain ASS in the alpine marsh ecosystem on the Tibetan Plateau. Our research revealed the powerful driving role of plants in transitions between states, which may support the conservation and restoration of global alpine marsh ecosystems.


Assuntos
Solo , Áreas Alagadas , Solo/química , Tibet , Água , Plantas , Ecossistema
11.
Sci Rep ; 14(1): 22968, 2024 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-39362921

RESUMO

The absorption of terahertz (THz) radiation by water molecules facilitates its application to several biomedical applications such as cancer detection. Therefore, it is critical for the THz technologies to be characterised with water content in a sample. In this paper, we analyse gelatine phantoms in the THz frequency range, with continuously varying hydration levels as they dry over time. Water molecules in close proximity to the protein molecule, termed 'bound water', feature properties different from the 'free water' molecules at larger distances. We find that a common model for predicting electromagnetic properties of phantoms and tissue samples, which assumes that only the free water varies with hydration while the bound water remains constant, does not agree well with measured results. To gain insight into this behaviour, we simultaneously measured the phantom in Raman spectroscopy, which shows a continuously varying concentration of bound water with hydration level. It follows from this investigation, that the permittivity contributions of neither the biomolecules nor water are expected to be linear with water density. This means that the often used, simple effective medium model will not be accurate for many biological tissues or phantoms.


Assuntos
Imagens de Fantasmas , Análise Espectral Raman , Água , Água/química , Análise Espectral Raman/métodos , Radiação Terahertz
12.
BMC Plant Biol ; 24(1): 924, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39363295

RESUMO

BACKGROUND: Peace lily (Spathiphyllum wallisii Regel) is an ornamental indoor plant with promising cut flower market, as well as antiviral, pharmacological and ecological potentials. Water deficiency can have sound effects on the growth performance and aesthetic quality of such plant. The aim of this study was to investigate the consequences of zeolite, biochar, and zeo-char loaded nano-nitrogen application on the growth performance and biochemical components of peace lily under water shortage conditions. An experiment was conducted over two consecutive seasons (2021-2022) at the experimental nursery of Ornamental Horticulture Department, Faculty of Agriculture, Cairo University, Giza, Egypt. Soil amendments; zeolite, biochar, and zeo-char loaded nano-nitrogen were prepared and applied to soil before cultivation. RESULTS: Our results revealed that the new combination treatment (zeo-char loaded nano-N) had an exceeding significant effect on most of the studied parameters. Vegetative traits such as plant height (35.7 and 35.9%), leaf number per plant (73.3 and 52.6%), leaf area (40.2 and 36.4%), stem diameter (28.7 and 27.1%), root number (100 and 43.5%) and length (105.7 and 101.9%) per plant, and fresh weight of leaves (23.2 and 21.6%) were significantly higher than control (commercially recommended dose of NPK) with the application of zeo-char loaded nano-N during the two growing seasons, respectively. Similar significant increments were obtained for some macro- (N, P, K, Mg, Ca) and micro- (Fe, Zn, Mn) elements with the same treatment relative to control. Chlorophyll (18.4%) and total carotenoids (82.9 and 32.6%), total carbohydrates (53.3 and 37.4%), phenolics (54.4 and 86.9%), flavonoids (31.7% and 41.8%) and tannins (69.2 and 50%), in addition to the phytohormone gibberellic acid (GA3) followed the same trend with the application of zeo-char loaded nano-N, increasing significantly over control. Leaf histological parameters and anatomical structure were enhanced with the new combination treatment in comparison with control. Antioxidant enzymes (catalase and peroxidase), proline and abscisic acid (ABA) exhibited significant declines with zeo-char loaded nano-N treatment relative to control. CONCLUSION: These findings suggest that incorporating soil amendments with nano- nutrients could provide a promising approach towards improving growth performance and quality of ornamental, medicinal and aromatic species under water deficiency conditions.


Assuntos
Carvão Vegetal , Nitrogênio , Zeolitas , Zeolitas/química , Zeolitas/farmacologia , Carvão Vegetal/química , Carvão Vegetal/farmacologia , Nitrogênio/metabolismo , Água , Solo/química , Fertilizantes/análise , Egito
13.
Postepy Biochem ; 70(3): 420-423, 2024 09 30.
Artigo em Polonês | MEDLINE | ID: mdl-39365571

RESUMO

How cells sense water is of fundamental importance in biology. Hygrosensation has been demonstrated in specialized sensory cells that sense extracellular moisture. Even in microorganisms, osmosensors do not sense water per se. Water-sensing mechanisms would have been necessary for organisms to migrate and survive in water-poor conditions and to evolve into multicellular organisms. Due to the potential ability of water molecules to bind to gas-binding sites in the heme-based sensing domains of gasoreceptors, I suggest that some of them could have a parallel role as protein aquareceptors. Just as gasoreceptors function in almost every cell, aquareceptors must also function in almost every cell. I think that aquareceptors must be present in the cell membrane, cytoplasm, and every organelle. I also wonder if hemoglobin could also be considered a putative aquareceptor.


Assuntos
Heme , Heme/metabolismo , Água/metabolismo , Humanos , Animais , Hemoglobinas/metabolismo
14.
Nat Commun ; 15(1): 8517, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39353937

RESUMO

Oil-in-water emulsion is a system with extensive applications in foods, cosmetics and coating industries, and it could also be designed into an artificial lipid droplet in recent works. However, the insights into the biophysical dynamic behaviors of such artificial lipid droplets are lacking. Here, we reveal an enzymatic reaction triggered endocytosis-like behavior in the oil-in-water emulsion lipid droplets. A thermodynamically favored recruitment of lipases onto the membrane of the droplets is demonstrated. We confirm that the hydrolysis of tributyrin by lipases can decrease the interfacial tension and increase the compressive force on the membrane, which are the two main driving forces for triggering the endocytosis-like behavior. The endocytosis-like behavior induced various emerging functionalities of the lipid droplets, including proteins, DNA or inorganic particles being efficiently sequestered into the oil droplet with reversible release as well as enhanced cascade enzymatic reaction. Overall, our studies are expected to open up a way to functionalize oil-in-water emulsions capable of life-inspired behaviors and tackle emerging challenges in bottom-up synthetic biology, revealing the unknown dynamic behaviors of lipid droplets in living organisms.


Assuntos
Emulsões , Endocitose , Lipase , Gotículas Lipídicas , Óleos , Triglicerídeos , Água , Emulsões/química , Lipase/metabolismo , Lipase/química , Água/química , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Triglicerídeos/química , Triglicerídeos/metabolismo , Óleos/química , Hidrólise
15.
PLoS One ; 19(10): e0310172, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39352922

RESUMO

Red bed composite polymers composed of weathered red bed soil, adhesive materials, and water-retaining materials have been applied as a new type of material for environmental restoration. However, the promotion and application of this material has been limited by a lack of understanding of its action mechanism in environmental restoration. The objective of this study is to innovatively propose a water‒soil-air‒plant mutual feedback mechanism based on this material. Therefore, water‒soil-air‒plant mutual feedback tests were conducted in this study under 3 initial water contents and 10 red bed composite polymers ratios. Key parameters, namely, water content, soil conductivity, pH, temperature, O2 and CO2 contents, pigeon pea (Cajanus cajan) germination number and plant height were monitored and analyzed. As the results, a mutual feedback mechanism driving water retention, soil consolidation, air retention, and plant rooting was revealed under the application of red bed composite polymers. And, suitable environments and optimal compositions for this material are proposed. The study results provide a theoretical basis for the large-scale application of red bed composite polymers.


Assuntos
Polímeros , Solo , Água , Solo/química , Água/química , Polímeros/química , Ar , Temperatura , Concentração de Íons de Hidrogênio , Germinação , Recuperação e Remediação Ambiental/métodos , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análise
16.
Nat Commun ; 15(1): 8487, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353935

RESUMO

Though conceptually attractive, the use of water-soluble prodrug technology to enhance oral bioavailability of highly insoluble small molecule therapeutics has not been widely adopted. In large part, this is due to the rapid enzymatic or chemical hydrolysis of prodrugs within the gastrointestinal tract, resulting in drug precipitation and no overall improvement in oral bioavailability relative to standard formulation strategies. We reasoned that an optimal water-soluble prodrug could be attained if the rate of prodrug hydrolysis were reduced to favor drug absorption rather than drug precipitation. In doing so, the rate of hydrolysis provides a pharmacokinetic control point for drug delivery. Herein, we report the discovery of a water-soluble promoiety (Sol-moiety) technology to optimize the oral bioavailability of highly insoluble small molecule therapeutics, possessing various functional groups, without the need for sophisticated, often toxic, lipid or organic solvent-based formulations. The power of the technology is demonstrated with marked pharmacokinetic improvement of the commercial drugs enzalutamide, vemurafenib, and paclitaxel. This led to a successful efficacy study of a water-soluble orally administered prodrug of paclitaxel in a mouse pancreatic tumor model.


Assuntos
Disponibilidade Biológica , Pró-Fármacos , Solubilidade , Água , Pró-Fármacos/farmacocinética , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química , Animais , Administração Oral , Camundongos , Água/química , Humanos , Paclitaxel/farmacocinética , Paclitaxel/administração & dosagem , Hidrólise , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Feminino
17.
F1000Res ; 13: 168, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39386085

RESUMO

Background: There are a variety of published standard methods and water chemistry recommendations for zebrafish ( Danio rerio) husbandry, but empirical evidence for their justification is often lacking, as is information on some variables that have important biological effects on fish. Importantly, these different recommendations could contribute to variability in results and fish welfare between or within institutions. Methods: Here we document the current range of water chemistry used by various research institutions around the world and report initial findings on their effects on the development and growth of zebrafish. Over 40 institutes responded to a survey that revealed a large variation in water chemistry used for zebrafish husbandry including differences in the set-points and acceptable ranges for temperature, pH and conductivity. In subsequent experiments, zebrafish ( D. rerio, WIK) embryos/larvae exposed to a large range of salt concentrations (50µM to 10mM Na + or 30 - 2500 µS/cm) and CO 2 levels (400 - 8,000 µatm). Results: Larvae exposed to the lowest salt concentration (5 µM Na + or < 30µS/cm) had a slower response to touch and their swim bladders were not inflated. Larvae exposed to 5-100 µM Na + were 5 % shorter in total body length than those exposed to higher salt concentrations (>100 µM Na +). Zebrafish embryo/larvae exposed to intermediate pCO 2 values (~2000 µatm) were 1 to 3.5% longer than those exposed to either ambient (400 µatm) or higher (4000 µatm) pCO 2, but pCO 2 did not affect developmental endpoints up to 4 dpf. Conclusions: Overall, we highlight the magnitude of variation in water chemistry used within zebrafish research and provide some empirical evidence to show that not all of these water conditions might be optimal for developing zebrafish and reproducibility of research, although further research is necessary to determine longer-term effects of water chemistry on older larvae, juveniles and adults.


Assuntos
Água , Peixe-Zebra , Peixe-Zebra/embriologia , Peixe-Zebra/crescimento & desenvolvimento , Animais , Água/química , Larva/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Temperatura , Concentração de Íons de Hidrogênio , Criação de Animais Domésticos/métodos
18.
Funct Plant Biol ; 512024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39388429

RESUMO

Drought-induced stress represents one of the most economically detrimental natural phenomena impacting grapevine (Vitis vinifera ) development, yield, and fruit characteristics. Also, auxin is one of the most important plant growth regulators that can reduce damage caused by stress in plants. In this study, the impact of exogenously sprayed auxin (0, 50, and 200mgL-1 ) on growth, biochemical, and anatomical parameters was investigated in two grapevine varieties (cvs. 'Rashe' and 'Fakhri') under water deficit. According to our findings, water deficit led to a notable decrease in growth, protein content, and anatomical parameters; but significantly enhanced electrolyte leakage. Grapevines exposed to water deficit exhibited substantial increases in total phenolic compounds and antioxidant activity. Applying 50mgL-1 napthalene acetic acid (NAA) reduced the effects of water deficit in both grapevine cultivars by decreasing electrolyte leakage (15% in 'Rashe' and 20% in 'Fakhri'), and accumulating protein content (22% 'Rashe' and 32% 'Fakhri'), total phenolic compounds (33%'Rashe' and 40% 'Fakhri'), and antioxidant capacity (11% 'Rashe' and 39% 'Fakhri'); anantomical parameters were also improved. However, application of 200mgL-1 NAA had adverse effects on growth and biochemical traits of grapevines, with a more pronounced impact on root growth and anatomical parameters compared to other NAA concentrations. In conclusion, the application of 50mgL-1 NAA enhanced grapevine growth, enabling them to better thrive under water deficit.


Assuntos
Antioxidantes , Ácidos Indolacéticos , Reguladores de Crescimento de Plantas , Vitis , Vitis/efeitos dos fármacos , Vitis/crescimento & desenvolvimento , Vitis/anatomia & histologia , Ácidos Indolacéticos/metabolismo , Ácidos Indolacéticos/farmacologia , Antioxidantes/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Água/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Secas , Proteínas de Plantas/metabolismo , Fenóis
19.
Physiol Plant ; 176(5): e14565, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39389922

RESUMO

Drought is a major environmental stress factor that negatively affects rice growth and yield. From a forward genetic perspective, we selected a drought-insensitive TILLING line (ditl4) from a gamma-ray-induced core mutant population (M10). Under drought conditions, ditl4 exhibited greater fresh weight, survival rate, chlorophyll, proline, and soluble sugar contents, and lower H2O2 and MDA levels than wild-type (WT). In addition, the activities of antioxidant enzymes, such as superoxide dismutase, catalase, and peroxidase, were higher in ditl4 than in the WT. In the relative water loss assay, dilt4 showed significantly decreased leaf curling and water loss compared to WT. Also, the ratio of "closed" stomata aperture was increased in ditl4 under drought stress, suggesting reduced transpiration to prevent water loss. The ditl4 mutant showed decreased stomatal conductance, transpiration, and CO2 assimilation and increased water use efficiency due to the low density of stomata. Whole-genome resequencing analysis of dilt4 identified a single nucleotide polymorphism (SNP) in OsDIRH2 (LOC_Os11g39640), annotated as a RING-H2 type E3 ligase, resulting in a premature stop codon. CRISPR/Cas9-mediated knock-out mutants (OsDIRH2a and OsDIRH2b) enhanced drought tolerance by lowering stomatal density compared to empty vector control plants. These findings suggested that ditl4 with low stomatal density would be useful as a genetic resource for a drought-tolerant breeding program to improve water-use efficiency.


Assuntos
Secas , Mutação , Oryza , Proteínas de Plantas , Estômatos de Plantas , Ubiquitina-Proteína Ligases , Oryza/genética , Oryza/fisiologia , Oryza/enzimologia , Estômatos de Plantas/fisiologia , Estômatos de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Água/metabolismo , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Clorofila/metabolismo , Resistência à Seca
20.
J Phys Chem Lett ; 15(40): 10190-10197, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39352724

RESUMO

Total-internal-reflection tip-enhanced Raman spectroscopy (TIR-TERS) imaging of amyloid-ß (Aß1-42-L34T) fibrils is performed with nanoscale spatial resolution in water, using TERS tips fabricated by bipolar electrodeposition. Ideal experimental parameters are corroborated by both theoretical simulations and TIR-TERS measurements. TIR-TERS imaging reveals the predominant parallel ß-sheet secondary structure of Aß1-42-L34T fibrils as well as the nanoscale spatial distribution of tyrosine, histidine, and phenylalanine aromatic amino acids. Their proportion in TERS spectra can be qualitatively explained by the combined effect of their localization in the Aß1-42-L34T fibril structure and their molecular orientation with respect to the excitation laser light polarization. Conclusions drawn from the TERS experiments in water corroborate and significantly enrich our previous study in ambient air, thus confirming that hydration has only a marginal impact on the structure of such amyloid fibrils. This first TIR-TERS study in liquid opens fascinating perspectives for future applications in biology.


Assuntos
Peptídeos beta-Amiloides , Amiloide , Análise Espectral Raman , Água , Análise Espectral Raman/métodos , Água/química , Peptídeos beta-Amiloides/química , Amiloide/química , Fragmentos de Peptídeos/química
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