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1.
Food Res Int ; 188: 114479, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823840

RESUMO

Freezing is a commonly used method for long-term storage of chicken wing products, of which disadvantages are mainly the product damage caused in the process. The aim of this study was to improve the freezing quality of chicken wings with a combination of phosphorus-free water retaining agent (WRA) and high-voltage electrostatic field (HVEF). The effect of WRA acting at different HVEF intensities (0, 1, 3, and 5 kV/cm) on the quality attributes of frozen chicken wings was investigated in 0, 7, 14, 21, 28 and 35 days of frozen storage. The results showed that WRA had functional properties of significantly improving the water holding capacity (WHC), color and texture properties, and fat stability of frozen chicken wing samples. The application of HVEF on this basis helped to promote the absorption of WRA and inhibit oxidative deterioration of chicken wing samples during frozen storage. Meanwhile, the combination of HVEF at 3 kV/cm was more prominent in terms of improvement in WHC, moisture content, color, protein secondary structure and microstructure integrity. This advantage had been consistently maintained with the extension of storage time. Overall, WRA combined with HVEF of 3 kV/cm can be used as an effective strategy to improve the freezing quality of chicken wing samples and has the potential to maintain the frozen chicken wing samples quality for a long time.


Assuntos
Galinhas , Congelamento , Eletricidade Estática , Água , Asas de Animais , Animais , Asas de Animais/química , Água/química , Conservação de Alimentos/métodos , Armazenamento de Alimentos/métodos , Fósforo/análise
2.
Food Res Int ; 188: 114399, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823854

RESUMO

In the context of replacing animal proteins in food matrices, rice proteins (RP) become promised because they come from an abundant plant source, are hypoallergenic, and have high digestibility and nutritional value. However, commercial protein isolates obtained by spray drying have low solubility and poor functionality, especially in their isoelectric point. One way to modify these properties is through interaction with polysaccharides, such as gum arabic (GA). Therefore, this work aims to evaluate the effects of pH and GA concentration on the interaction and emulsifying activity of RP:GA coacervates. First, the effects of pH (2.5 to 7.0) and GA concentrations (0.2 to 1.0 wt%, giving rise to RP:GA mass ratios of 1:0.2 to 1:1.0) in RP:GA blends were evaluated. The results demonstrated that biopolymers present opposite net charges at pH between 2.5 and 4.0. At pH 3.0, insoluble coacervates with complete charge neutralization were formed by electrostatic interactions, while at pH 5.0 it was observed that the presence of GA prevented the RP massive aggregation. Second, selected blends with 0.4 or 1.0 wt% of GA (RP:GA mass ratios of 1:0.4 or 1:1.0) at pH 3.0 or 5.0 were tested for their ability to stabilize oil-in-water emulsions. The emulsions were characterized for 21 days. It was observed that the GA increased the stability of RP emulsions, regardless of the pH and polysaccharide concentration. Taken together, our results show that it is possible to combine RP and GA to improve the emulsifying properties of these plant proteins at pH conditions close to their isoelectric point, expanding the possibility of implementation in food systems.


Assuntos
Emulsões , Goma Arábica , Oryza , Proteínas de Plantas , Polissacarídeos , Água , Goma Arábica/química , Emulsões/química , Concentração de Íons de Hidrogênio , Proteínas de Plantas/química , Oryza/química , Polissacarídeos/química , Água/química , Emulsificantes/química , Solubilidade
3.
Food Res Int ; 188: 114461, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823861

RESUMO

Myofibrillar proteins are crucial for gel formation in processed meat products such as sausages and meat patties. Freeze-thaw cycles can alter protein properties, impacting gel stability and product quality. This study aims to investigate the potential of thawed drip and its membrane-separated components as potential antifreeze agents to retard denaturation, oxidation and gel deterioration of myofibrillar proteins during freezing-thawing cycles of pork patties. The thawed drip and its membrane-separated components of > 10 kDa and < 10 kDa, along with deionized water, were added to minced pork at 10 % mass fraction and subjected to increasing freeze-thaw cycles. Results showed that the addition of thawed drip and its membrane separation components inhibited denaturation and structural changes of myofibrillar proteins, evidenced by reduced surface hydrophobicity and carbonyl content, increased free sulfhydryl groups, protein solubility and α-helix, as compared to the deionized water group. Correspondingly, improved gel properties including water-holding capacity, textural parameters and denser network structure were observed with the addition of thawed drip and its membrane separation components. Denaturation and oxidation of myofibrillar proteins were positively correlated with gel deterioration during freezing-thawing cycles. We here propose a role of thawed drip and its membrane separation components as cryoprotectants against myofibrillar protein gel deterioration during freeze-thawing cycles.


Assuntos
Congelamento , Géis , Proteínas Musculares , Miofibrilas , Animais , Géis/química , Suínos , Proteínas Musculares/química , Miofibrilas/química , Manipulação de Alimentos/métodos , Desnaturação Proteica , Produtos da Carne/análise , Interações Hidrofóbicas e Hidrofílicas , Solubilidade , Água/química , Oxirredução
4.
Food Res Int ; 188: 114493, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823876

RESUMO

In this paper, two emulsion systems with high and low solid fat contents were prepared from 20 % water phase and 80 % oil phase by adjusting the palm oil/palm stearin/soybean oil ratio. Different ultrasonic power and time were used for the pretreatment of emulsion with different solid fat content, and the application characteristics of ultrasonic in W/O emulsions were explored and evaluated. Directly using high-intensity ultrasound to prepare fatty emulsions would weaken the hardness and storage modulus G' of the samples. Although ultrasound reduced the size of fat crystals in emulsions, the interaction between water droplets and fat crystals needs to be considered. After ultrasonic treatment, water droplets were difficult to immobilize on the crystal surface and thus acted as an active filler to stabilize the emulsion together with the fat crystal network. In high solid fat emulsion systems, an increase in ultrasound power (from 100 W to 200 W) could more affect the crystallization behavior of fats than an increase in ultrasound duration (from 30 s to 60 s), and the distribution of crystals and droplets was more uniform. In the low solid fat emulsion system, the texture of the sample after ultrasonic treatment was softer, and the surface was more delicate and smoother. However, the higher ultrasonic intensity (200 W) was not conducive to the preparation of the spread. Although the ultrasound with excessive intensity promoted the formation of small crystals, it would also lead to the aggregation of small crystals. These small crystals cannot form a uniform crystal network, which increases the fluidity of emulsions.


Assuntos
Cristalização , Emulsões , Óleo de Palmeira , Tamanho da Partícula , Água , Emulsões/química , Água/química , Óleo de Palmeira/química , Óleo de Soja/química , Ondas Ultrassônicas , Ultrassom
5.
Food Res Int ; 188: 114503, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823881

RESUMO

The aim of this work was to investigate wheat gluten protein network structure throughout the deep-frying process and evaluate its contribution to frying-induced micro- and macrostructure development. Gluten polymerization, gluten-water interactions, and molecular mobility were assessed as a function of the deep-frying time (0 - 180 s) for gluten-water model systems of differing hydration levels (40 - 60 % moisture content). Results showed that gluten protein extractability decreased considerably upon deep frying (5 s) mainly due to glutenin polymerization by disulfide covalent cross-linking. Stronger gliadin and glutenin protein-protein interactions were attributed to the formation of covalent linkages and evaporation of water interacting with protein chains. Longer deep-frying (> 60 s) resulted in progressively lower protein extractabilities, mainly due to the loss in gliadin protein extractability, which was associated with gliadin co-polymerization with glutenin by thiol-disulfide exchange reactions. The mobility of gluten polymers was substantially reduced during deep-frying (based on the lower T2 relaxation time of the proton fraction representing the non-exchanging protons of gluten) and gluten proteins gradually transitioned from the rubbery to the glassy state (based on the increased area of said protons). The sample volume during deep-frying was strongly correlated to the reduced protein extractability (r = -0.792, p < 0.001) and T2 relaxation time of non-exchanging protons of gluten proteins (r = -0.866, p < 0.001) thus demonstrating that the extent of gluten structural expansion as a result of deep-frying is dictated both by the polymerization of proteins and the reduction in their molecular mobility.


Assuntos
Culinária , Gliadina , Glutens , Temperatura Alta , Triticum , Glutens/química , Triticum/química , Culinária/métodos , Gliadina/química , Polimerização , Água/química
6.
Carbohydr Polym ; 339: 122235, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823906

RESUMO

This study explored the physicochemical properties and structural characteristics of Agrocybe cylindracea polysaccharides at four developmental stages, as well as their dynamic evolution during maturation. Results showed that the polysaccharides from A. cylindracea water extract exhibited similar structural characteristics across all four maturity stages, despite a significant reduction in yields. Four water-soluble heteroglycans, including one high molecular weight (ACPM-Et50-I) and three low molecular weight (ACPM-Et50-II, ACPM-Et60, ACPM-Et80), were isolated from A. cylindracea at each maturity stage. ACPM-Et50-I was identified as branched heterogalactans, while ACPM-Et60 and ACPM-Et80 were branched heteroglucans. However, ACPM-Et50-II was characterized as a branched glucuronofucogalactoglucan at the tide-turning stage but a glucuronofucoglucogalactan at the pileus expansion stage due to the increase of its α-(1 â†’ 6)-D-Galp. In general, although the structural skeletons of most A. cylindracea heteroglycans were similar during maturation as shown by their highly consistent glycosyl linkages, there were still differences in the distribution of some heteroglucans. This work has for the first time reported a glucuronofucogalactoglucan in A. cylindracea and its dynamic evolution during maturation, which may facilitate the potential application of A. cylindracea in food and biomedicine industries.


Assuntos
Agrocybe , Água , Água/química , Agrocybe/química , Glucanos/química , Polissacarídeos/química , Peso Molecular
7.
PLoS One ; 19(6): e0303900, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38843120

RESUMO

BACKGROUND: Candesartan cilexetil (CC) is a selective angiotensin II receptor antagonist widely used to treat hypertension. CC is a substrate of P-glycoprotein (P-gp), causing its efflux to the intestinal lumen. It is also practically insoluble in water and has low oral bioavailability (14%). Thus, the current study aims to improve the in vitro dissolution of CC by developing solid dispersion systems (SDSs) and corroborating the in vitro results using a simulated pharmacokinetics study. METHODS: The SDSs were prepared using polyvinyl pyrrolidone (PVP) as a water-soluble polymer, Eudragit E100 (EE100) as a pH-dependent soluble carrier, and a combination of these two polymers. The saturation solubility and the dissolution rate studies of the prepared systems in three dissolution media were performed. The optimized system SE-EE5 was selected for further investigations, including DSC, XRD, FTIR, FESEM, DLS, TSEM, IVIVC convolution study, and stability studies. RESULTS: The solubility of CC significantly increased by a factor of 27,037.344 when formulated as a solid dispersion matrix using EE100 at a ratio of 1:5 (w/w) drug to polymer (SE-EE5 SD), compared to the solubility of the pure drug. The mechanism of solubility and dissolution rate enhancement of CC by the optimized SDS was found to be via the conversion of the crystalline CC into the amorphous form as well as nanoparticles formation upon dissolution at a pH below 5. The instrumental analysis tests showed good compatibility between CC and EE100 and there was no chemical interaction between the drug and the polymer. Moreover, the stability tests confirmed that the optimized system was stable after three months of storage at 25°C. CONCLUSION: The utilization of the solid dispersion technique employing EE 100 polymer as a matrix demonstrates significant success in enhancing the solubility, dissolution, and subsequently, the bioavailability of water-insoluble drugs like CC.


Assuntos
Benzimidazóis , Compostos de Bifenilo , Polímeros , Solubilidade , Tetrazóis , Benzimidazóis/química , Benzimidazóis/farmacocinética , Tetrazóis/química , Tetrazóis/farmacocinética , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacocinética , Polímeros/química , Polímeros/farmacocinética , Povidona/química , Água/química , Concentração de Íons de Hidrogênio , Disponibilidade Biológica , Estabilidade de Medicamentos , Liberação Controlada de Fármacos , Acrilatos
8.
PLoS One ; 19(6): e0303210, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38843174

RESUMO

Cellular metabolic activity can be detected by tetrazolium-based colorimetric assays, which rely on dehydrogenase enzymes from living cells to reduce tetrazolium compounds into colored formazan products. Although these methods have been used in different fields of microbiology, their application to the detection of bacteria with plastic-degrading activity has not been well documented. Here, we report a microplate-adapted method for the detection of bacteria metabolically active on the commercial polyester polyurethane (PU) Impranil®DLN using the tetrazolium salt 2,3-bis [2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide (XTT). Bacterial cells that are active on PU reduce XTT to a water-soluble orange dye, which can be quantitatively measured using a microplate reader. We used the Pseudomonas putida KT2440 strain as a study model. Its metabolic activity on Impranil detected by our novel method was further verified by Fourier-transform infrared spectroscopy (FTIR) analyses. Measurements of the absorbance of reduced XTT at 470 nm in microplate wells were not affected by the colloidal properties of Impranil or cell density. In summary, we provide here an easy and high-throughput method for screening bacteria active on PU that can be adapted to other plastic substrates.


Assuntos
Poliuretanos , Pseudomonas putida , Sais de Tetrazólio , Poliuretanos/química , Pseudomonas putida/metabolismo , Sais de Tetrazólio/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Água/química , Colorimetria/métodos
9.
Eur Phys J E Soft Matter ; 47(6): 37, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829453

RESUMO

In this study, we demonstrate the fabrication of polymersomes, protein-blended polymersomes, and polymeric microcapsules using droplet microfluidics. Polymersomes with uniform, single bilayers and controlled diameters are assembled from water-in-oil-in-water double-emulsion droplets. This technique relies on adjusting the interfacial energies of the droplet to completely separate the polymer-stabilized inner core from the oil shell. Protein-blended polymersomes are prepared by dissolving protein in the inner and outer phases of polymer-stabilized droplets. Cell-sized polymeric microcapsules are assembled by size reduction in the inner core through osmosis followed by evaporation of the middle phase. All methods are developed and validated using the same glass-capillary microfluidic apparatus. This integrative approach not only demonstrates the versatility of our setup, but also holds significant promise for standardizing and customizing the production of polymer-based artificial cells.


Assuntos
Células Artificiais , Polímeros , Células Artificiais/química , Polímeros/química , Polímeros/síntese química , Emulsões/química , Cápsulas/química , Microfluídica/métodos , Água/química , Técnicas Analíticas Microfluídicas , Proteínas/química
10.
Amino Acids ; 56(1): 40, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847939

RESUMO

Pelodiscus sinensis meat is a nutritional food and tonic with angiotensin-converting enzyme (ACE) inhibitory activities. To identify the bioactive substances responsible, several bioinformatics methods were integrated to enable a virtual screening for bioactive peptides in proteins identified within a water-soluble protein fraction of Pelodiscus sinensis meat by Shotgun proteomics. The peptides were generated from the identified proteins by in silico proteolysis using six proteases. A comparison of the numbers of proteins suitable for digestion with each enzyme and the iBAQ (intensity-based absolute quantification) values for these proteins revealed that bromelain and papain were the most suitable proteases for this sample. Next, the water solubility, toxicity, and ADMET (absorption/distribution/metabolism/excretion/toxicity) properties of these peptides were evaluated in silico. Finally, a novel ACE inhibitory peptide IEWEF with an IC50 value of 41.33 µM was identified. The activity of the synthesized peptide was verified in vitro, and it was shown to be a non-competitive ACE inhibitor. Molecular docking revealed that IEWEF could tightly bind to C-ACE, and N-ACE with energies less than 0 kJ mol-1, and the peptide IEWEF can form hydrogen bonds with C-ACE and N-ACE respectively. These results provide evidence that bioactive peptides in the water-soluble protein fraction account for (at least) some of the ACE inhibitory activities observed in Pelodiscus sinensis meat. Furthermore, our research provides a workflow for the efficient identification of novel ACE inhibitory peptides from complex protein mixtures.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Simulação de Acoplamento Molecular , Peptídeos , Hidrolisados de Proteína , Solubilidade , Inibidores da Enzima Conversora de Angiotensina/química , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Animais , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/metabolismo , Água/química , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Papaína/metabolismo , Papaína/antagonistas & inibidores , Papaína/química , Proteínas de Peixes/química , Proteínas de Peixes/metabolismo
11.
Food Res Int ; 186: 114400, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729703

RESUMO

Since hydrothermal treatments can enhance resistant starch (RS) content in rice and provide health benefits when consumed, a less laborious and non-destructive method to determine RS content is needed. Terahertz (THz) spectroscopy is hypothesized as a suitable method to quantify RS content in rice after hydrothermal treatment with its sensitivity for the intermolecular forces increase in the formation of RS. In this study, we first used the traditional in vitro hydrolysis method to determine the content of RS in rice. Then, the potential of starch absorbance peaks to quantify RS content after three commonly used hydrothermal methods, soaking, mild heat-moisture treatment, and parboiling, was investigated. The second derivative intensities of the peak at 9.0, 10.5, 12.1, and 13.1 THz were confirmed as being correlated with RS content and showed the high accuracy to predict RS content in samples (R2 > 0.96). Our results indicate the RS content of hydrothermally treated rice can be accurately quantified using these peaks.


Assuntos
Temperatura Alta , Oryza , Amido , Espectroscopia Terahertz , Oryza/química , Amido/análise , Espectroscopia Terahertz/métodos , Hidrólise , Amido Resistente/análise , Manipulação de Alimentos/métodos , Água/química
12.
Food Res Int ; 186: 114320, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729710

RESUMO

High-moisture extrusion (HME) is widely used to produce meat analogues. During HME the plant-based materials experience thermal and mechanical stresses. It is complicated to separate their effects on the final products because these effects are interrelated. In this study we hypothesize that the intensity of the thermal treatment can explain a large part of the physicochemical changes that occur during extrusion. For this reason, near-infrared (NIR) spectroscopy was used as a novel method to quantify the thermal process intensity during HME. High-temperature shear cell (HTSC) processing was used to create a partial least squares (PLS) regression curve for processing temperature under controlled processing conditions (root mean standard error of cross-validation (RMSECV) = 4.00 °C, coefficient of determination of cross-validation (R2CV) = 0.97). This PLS regression model was then applied to HME extrudates produced at different screw speeds (200-1200 rpm) and barrel temperatures (100-160 °C) with two different screw profiles to calculate the equivalent shear cell temperature as a measure for thermal process intensity. This equivalent shear cell temperature reflects the effects of changes in local temperature conditions, residence time and thermal stresses. Furthermore, it can be related to the degree of texturization of the extrudates. This information can be used to gain new insights into the effect of various process parameters during HME on the thermal process intensity and extrudate quality.


Assuntos
Manipulação de Alimentos , Temperatura Alta , Proteínas de Soja , Espectroscopia de Luz Próxima ao Infravermelho , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Manipulação de Alimentos/métodos , Proteínas de Soja/química , Proteínas de Soja/análise , Análise dos Mínimos Quadrados , Água/química
13.
Food Res Int ; 186: 114374, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729731

RESUMO

As a crucial component of the fungal cell membranes, ergosterol has been demonstrated to possess surface activity attributed to its hydrophobic region and polar group. However, further investigation is required to explore its emulsification behavior upon migration to the oil-water interface. Therefore, this study was conducted to analyze the interface properties of ergosterol as a stabilizer for water in oil (W/O) emulsion. Moreover, the emulsion prepared under the optimal conditions was utilized to load the water-soluble bioactive substance with the chlorogenic acid as the model molecules. Our results showed that the contact angle of ergosterol was 117.017°, and its dynamic interfacial tension was obviously lower than that of a pure water-oil system. When the ratio of water to oil was 4: 6, and the content of ergosterol was 3.5 % (ergosterol/oil phase, w/w), the W/O emulsion had smaller particle size (438 nm), higher apparent viscosity, and better stability. Meanwhile, the stability of loaded chlorogenic acid was improved under unfavorable conditions (pH 1.2, 90 °C, ultraviolet irradiation, and oxidation), which were 73.87 %, 59.53 %, 62.53 %, and 69.73 %, respectively. Additionally, the bioaccessibility of chlorogenic acid (38.75 %) and ergosterol (33.69 %), and the scavenging rates of the emulsion on DPPH radicals (81.00 %) and hydroxyl radicals (82.30 %) were also enhanced. Therefore, a novel W/O Pickering emulsion was prepared in this work using ergosterol as an emulsifier solely, which has great potential for application in oil-based food and nutraceutical formulations.


Assuntos
Ácido Clorogênico , Emulsificantes , Emulsões , Ergosterol , Tamanho da Partícula , Água , Ergosterol/química , Emulsões/química , Emulsificantes/química , Água/química , Ácido Clorogênico/química , Viscosidade , Antioxidantes/química , Óleos/química , Concentração de Íons de Hidrogênio
14.
J Chem Phys ; 160(18)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38726933

RESUMO

We investigate how electronic excitations and subsequent dissipative dynamics in the water soluble chlorophyll-binding protein (WSCP) are connected to features in two-dimensional (2D) electronic spectra, thereby comparing results from our theoretical approach with experimental data from the literature. Our calculations rely on third-order response functions, which we derived from a second-order cumulant expansion of the dissipative dynamics involving the partial ordering prescription, assuming a fast vibrational relaxation in the potential energy surfaces of excitons. Depending on whether the WSCP complex containing a tetrameric arrangement of pigments composed of two dimers with weak excitonic coupling between them binds the chlorophyll variant Chl a or Chl b, the resulting linear absorption and circular dichroism spectra and particularly the 2D spectra exhibit substantial differences in line shapes. These differences between Chl a WSCP and Chl b WSCP cannot be explained by the slightly modified excitonic couplings within the two variants. In the case of Chl a WSCP, the assumption of equivalent dimer subunits facilitates a reproduction of substantial features from the experiment by the calculations. In contrast, for Chl b WSCP, we have to assume that the sample, in addition to Chl b dimers, contains a small but distinct fraction of chemically modified Chl b pigments. The existence of such Chl b derivates has been proposed by Pieper et al. [J. Phys. Chem. B 115, 4042 (2011)] based on low-temperature absorption and hole-burning spectroscopy. Here, we provide independent evidence.


Assuntos
Proteínas de Ligação à Clorofila , Clorofila , Água , Clorofila/química , Água/química , Proteínas de Ligação à Clorofila/química , Análise Espectral/métodos , Solubilidade , Dicroísmo Circular
15.
Environ Microbiol ; 26(5): e16627, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38733112

RESUMO

Soil structure and aggregation are crucial for soil functionality, particularly under drought conditions. Saprobic soil fungi, known for their resilience in low moisture conditions, are recognized for their influence on soil aggregate dynamics. In this study, we explored the potential of fungal amendments to enhance soil aggregation and hydrological properties across different moisture regimes. We used a selection of 29 fungal isolates, recovered from soils treated under drought conditions and varying in colony density and growth rate, for single-strain inoculation into sterilized soil microcosms under either low or high moisture (≤-0.96 and -0.03 MPa, respectively). After 8 weeks, we assessed soil aggregate formation and stability, along with soil properties such as soil water content, water hydrophobicity, sorptivity, total fungal biomass and water potential. Our findings indicate that fungal inoculation altered soil hydrological properties and improved soil aggregation, with effects varying based on the fungal strains and soil moisture levels. We found a positive correlation between fungal biomass and enhanced soil aggregate formation and stabilization, achieved by connecting soil particles via hyphae and modifying soil aggregate sorptivity. The improvement in soil water potential was observed only when the initial moisture level was not critical for fungal activity. Overall, our results highlight the potential of using fungal inoculation to improve the structure of agricultural soil under drought conditions, thereby introducing new possibilities for soil management in the context of climate change.


Assuntos
Fungos , Microbiologia do Solo , Solo , Água , Solo/química , Fungos/crescimento & desenvolvimento , Água/química , Biomassa , Secas
16.
Sci Adv ; 10(19): eade9520, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38718112

RESUMO

Fast collective motions are widely present in biomolecules, but their functional relevance remains unclear. Herein, we reveal that fast collective motions of backbone are critical to the water transfer of aquaporin Z (AqpZ) by using solid-state nuclear magnetic resonance (ssNMR) spectroscopy and molecular dynamics (MD) simulations. A total of 212 residue site-specific dipolar order parameters and 158 15N spin relaxation rates of the backbone are measured by combining the 13C- and 1H-detected multidimensional ssNMR spectra. Analysis of these experimental data by theoretic models suggests that the small-amplitude (~10°) collective motions of the transmembrane α helices on the nanosecond-to-microsecond timescales are dominant for the dynamics of AqpZ. The MD simulations demonstrate that these collective motions are critical to the water transfer efficiency of AqpZ by facilitating the opening of the channel and accelerating the water-residue hydrogen bonds renewing in the selectivity filter region.


Assuntos
Aquaporinas , Simulação de Dinâmica Molecular , Água , Água/química , Aquaporinas/química , Aquaporinas/metabolismo , Conformação Proteica em alfa-Hélice , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Ressonância Magnética Nuclear Biomolecular , Proteínas de Escherichia coli
17.
Luminescence ; 39(5): e4743, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38692854

RESUMO

A unique luminescent lanthanide metal-organic framework (LnMOF)-based fluorescence detection platform was utilized to achieve sensitive detection of vomitoxin (VT) and oxytetracycline hydrochloride (OTC-HCL) without the use of antibodies or biomolecular modifications. The sensor had a fluorescence quenching constant of 9.74 × 106 M-1 and a low detection limit of 0.68 nM for vomitoxin. Notably, this is the first example of a Tb-MOF sensor for fluorescence detection of vomitoxin. We further investigated its response to two mycotoxins, aflatoxin B1 and ochratoxin A, and found that their Stern-Volmer fluorescence quenching constants were lower than those of VT. In addition, the fluorescence sensor realized sensitive detection of OTC-HCL with a detection limit of 0.039 µM. In conclusion, the method has great potential as a sensitive and simple technique to detect VT and OTC-HCL in water.


Assuntos
Estruturas Metalorgânicas , Oxitetraciclina , Térbio , Oxitetraciclina/análise , Oxitetraciclina/química , Térbio/química , Estruturas Metalorgânicas/química , Espectrometria de Fluorescência , Corantes Fluorescentes/química , Limite de Detecção , Água/química , Fluorescência , Poluentes Químicos da Água/análise
18.
PLoS One ; 19(5): e0303096, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38713656

RESUMO

Fast-growing poplar plantations are considered a great benefit to timber production, but water availability is a key factor limiting their growth and development, especially in arid and semi-arid ecosystems. Super-absorbent polymers facilitate more water retention in soil after rain or irrigation, and they are able to release water gradually during plant growth. This study aimed to examine the effects of reduced irrigation (60% and 30% of conventional border irrigation) co-applied with super-absorbent polymers (0, 40 kg/ha) on root exudates, enzyme activities, microbial functional diversity in rhizosphere soil, and volume increments in poplar (Populus euramericana cv. 'Neva'). The results showed that 60% border irrigation co-applied with super-absorbent polymers significantly increased the content of organic acids, amino acids and total sugars in the root exudates, and the activities of invertase, urease, dehydrogenase, and catalase in the rhizosphere soil in comparison to conventional border irrigation without super-absorbent polymers. Meanwhile, this treatment also enhanced the average well-color development, Shannon index, and McIntosh index, but decreased the Simpson index. Additionally, the average volume growth rate and relative water content of leaves reached their maximum using 60% irrigation with super-absorbent polymers, which was significantly higher than other treatments. However, using 30% irrigation with super-absorbent polymers, had a smaller effect on rhizosphere soil and volume growth than 60% irrigation with super-absorbent polymers. Therefore, using an appropriate water-saving irrigation measure (60% conventional border irrigation with super-absorbent polymers) can help to improve enzyme activities and microbial diversity in the rhizosphere soil while promoting the growth of poplar trees.


Assuntos
Irrigação Agrícola , Polímeros , Populus , Rizosfera , Microbiologia do Solo , Populus/crescimento & desenvolvimento , Populus/microbiologia , Irrigação Agrícola/métodos , Polímeros/química , Raízes de Plantas/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Solo/química , Água/química
19.
Water Sci Technol ; 89(9): 2512-2522, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38747964

RESUMO

This manuscript presents a novel approach for developing an environmentally friendly and effective oil-water separation membrane. Achieving a superhydrophobic (SH) coating on textile fabric (TF) involved a two-step process. Initially, the surface roughness was enhanced by applying bio-zinc oxide (ZnO) nanoparticles obtained from Thymbra spicata L. Subsequently, the roughened surface was modified with stearic acid, a material known for its low surface energy. The bio-ZnO nanoparticles exhibit a circular morphology with an average size of 21 nm. The coating demonstrated remarkable mechanical stability, maintaining SH properties even after an abrasion length of 300 mm. Chemical stability studies revealed that the prepared membrane retained SH properties within a pH range of 5-11, which ensures robust performance. Absorption capacity measurements showcased different capacities for n-hexane (Hex), corn oil (C.O), and silicone oil (S.O), with consistent performance over 10 absorption-desorption cycles. High oil-water separation efficiencies were achieved for hexane, C.O, and S.O, emphasizing the coating's versatility. Flux rate measurements demonstrated that oil passed through the membrane efficiently, with the highest flux observed for Hex. The prepared SH membrane has superior mechanical and chemical stability and high separation efficiencies, which positions it as a promising candidate for diverse industrial applications.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Óxido de Zinco , Óxido de Zinco/química , Água/química , Óleos/química
20.
Molecules ; 29(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38731509

RESUMO

The aim of this study was to develop microcapsules containing juniper or black pepper essential oils, using a combination of faba bean protein and chia seed polysaccharides (in ratios of 1:1, 1:2, 2:1). By synergizing these two polymers, our goal was to enhance the efficiency of essential oil microencapsulation, opening up various applications in the food industry. Additionally, we aimed to investigate the influence of different polymer mixing ratios on the properties of the resulting microcapsules and the course of the complex coacervation process. To dissolve the essential oils and limit their evaporation, soybean and rapeseed oils were used. The powders resulting from the freeze-drying of coacervates underwent testing to assess microencapsulation efficiency (65.64-87.85%), density, flowability, water content, solubility, and hygroscopicity. Additionally, FT-IR and DSC analyses were conducted. FT-IR analysis confirmed the interactions between the components of the microcapsules, and these interactions were reflected in their high thermal resistance, especially at a protein-to-polysaccharide ratio of 2:1 (177.2 °C). The water content in the obtained powders was low (3.72-7.65%), but it contributed to their hygroscopicity (40.40-76.98%).


Assuntos
Cápsulas , Composição de Medicamentos , Óleos Voláteis , Proteínas de Plantas , Polissacarídeos , Salvia , Sementes , Vicia faba , Polissacarídeos/química , Sementes/química , Vicia faba/química , Composição de Medicamentos/métodos , Óleos Voláteis/química , Proteínas de Plantas/química , Salvia/química , Cápsulas/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
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