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1.
Food Res Int ; 183: 114212, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760140

RESUMO

This study evaluated the effect of ultrasound treatment combined or not with heat treatment applied to lentil protein isolate (LPI) aiming to enhance its ability to stabilize high internal phase emulsions (HIPE). LPI dispersion (2%, w/w) was ultrasound-treated at 60% (UA) and 70% (UB) amplitude for 7 min; these samples were subjected to and then heat treatments at 70 °C (UAT70 and UBT70, respectively) or 80 °C (UAT80 and UBT80, respectively) for 20 min. HIPEs were produced with 25% untreated and treated LPI dispersions and 75% soybean oil using a rotor-stator (15,500 rpm/1 min). The LPI dispersions were evaluated for particle size, solubility, differential scanning calorimetry, electrophoresis, secondary structure estimation (circular dichroism and FT-IR), intrinsic fluorescence, surface hydrophobicity, and free sulfhydryl groups content. The HIPEs were evaluated for droplet size, morphology, rheology, centrifugal stability, and the Turbiscan test. Ultrasound treatment decreased LPI dispersions' particle size (∼80%) and increased solubility (∼90%). Intrinsic fluorescence and surface hydrophobicity confirmed LPI modification due to the exposure to hydrophobic patches. The combination of ultrasound and heat treatments resulted in a reduction in the free sulfhydryl group content of LPI. HIPEs produced with ultrasound-heat-treated LPI had a lower droplet size distribution mode, greater oil retention values in the HIPE structure (> 98%), lower Turbiscan stability index (< 2), and a firmer and more homogeneous appearance compared to HIPE produced with untreated LPI, indicating higher stability for the HIPEs stabilized by treated LPI. Therefore, combining ultrasound and heat treatments could be an effective method for the functional modification of lentil proteins, allowing their application as HIPE emulsifiers.


Assuntos
Emulsões , Temperatura Alta , Lens (Planta) , Tamanho da Partícula , Proteínas de Plantas , Lens (Planta)/química , Emulsões/química , Proteínas de Plantas/química , Solubilidade , Interações Hidrofóbicas e Hidrofílicas , Manipulação de Alimentos/métodos , Varredura Diferencial de Calorimetria , Espectroscopia de Infravermelho com Transformada de Fourier , Dicroísmo Circular , Reologia , Ultrassom/métodos , Sonicação/métodos
2.
J R Soc Interface ; 21(214): 20240046, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38774961

RESUMO

Many microorganisms propel themselves through complex media by deforming their flagella. The beat is thought to emerge from interactions between forces of the surrounding fluid, the passive elastic response from deformations of the flagellum and active forces from internal molecular motors. The beat varies in response to changes in the fluid rheology, including elasticity, but there are limited data on how systematic changes in elasticity alter the beat. This work analyses a related problem with fixed-strength driving force: the emergence of beating of an elastic planar filament driven by a follower force at the tip of a viscoelastic fluid. This analysis examines how the onset of oscillations depends on the strength of the force and viscoelastic parameters. Compared to a Newtonian fluid, it takes more force to induce the instability in viscoelastic fluids, and the frequency of the oscillation is higher. The linear analysis predicts that the frequency increases with the fluid relaxation time. Using numerical simulations, the model predictions are compared with experimental data on frequency changes in the bi-flagellated alga Chlamydomonas reinhardtii. The model shows the same trends in response to changes in both fluid viscosity and Deborah number and thus provides a possible mechanistic understanding of the experimental observations.


Assuntos
Chlamydomonas reinhardtii , Elasticidade , Modelos Biológicos , Chlamydomonas reinhardtii/fisiologia , Viscosidade , Flagelos/fisiologia , Reologia
3.
Braz J Biol ; 84: e281236, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38775525

RESUMO

Munguba butter has bioactive compounds such as vitamin E and phytosterols, which has valued its application in the development of new products, with advantages in its use in emulsified formulations. Therefore, the objective was to develop and evaluate the stability of a nanoemulsion containing munguba butter as the oily phase. Munguba butter was extracted by the ultrasound assisted method and its HLB (hydrophilic-lipophilic balance) was determined. Next, formulations varying the concentration of butter from 1-40% were developed and classified into liquid or solid emulsion and phase separation. Liquid emulsions were evaluated for hydrodynamic particle diameter, polydispersity index (PDI), Zeta potential (ζ), rheological characterization, and stability assays. The butter had an HLB of 6.98. The NE 1.0% formulation was selected and demonstrated to be unstable at high temperatures (45 ± 2 °C) and remained stable at room temperature, refrigeration and light radiation for 90 days. Munguba butter, because it has high amounts of saturated fatty acids, hinders its application in the development of new products. However, the success in the development of the NE 1.0% formulation is noteworthy, remaining stable when exposed to refrigeration, room temperature and light radiation.


Assuntos
Emulsões , Emulsões/química , Vigna/química , Manteiga/análise , Tamanho da Partícula , Estabilidade de Medicamentos , Reologia
4.
Food Res Int ; 187: 114373, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763649

RESUMO

Effect of complexation of three medium-chain fatty acids (octanoic, decylic and lauric acid, OA, DA and LA, respectively) on structural characteristics, physicochemical properties and digestion behaviors of cassava starch (CS) was investigated. Current study indicated that LA was more easily to combine with CS (complex index 88.9%), followed by DA (80.9%), which was also consistent with their corresponding complexed lipids content. Following the investigation of morphology, short-range ordered structure, helical structure, crystalline/amorphous region and fractal dimension of the various complexes, all cassava starch-fatty acids complexes (CS-FAs) were characterized with a flaked morphology rather than a round morphology in native starch (control CS). X-ray diffraction demonstrated that all CS-FAs had a V-type crystalline structure, and nuclear magnetic resonance spectroscopy confirmed that the complexes made from different fatty acids displayed similar V6 or V7 type polymorphs. Interestingly, small-angle X-ray scattering analysis revealed that α value became greater following increased carbon chain length of fatty acids, indicating the formation of a more ordered fractal structure in the aggregates. Changes in rheological parameters G' and G'' indicated that starch complexed with fatty acids was more likely to form a gel network, but difference among three CS-FAs complexes was significant, which might be contributed to their corresponding hydrophobicity and hydrophilicity raised from individual fatty acids. Importantly, digestion indicated that CS-LA complexes had the lowest hydrolysis degree, followed by the greatest RS content, indicating the importance of chain length of fatty acids for manipulating the fine structure and functionality of the complexes.


Assuntos
Digestão , Ácidos Graxos , Ácidos Láuricos , Manihot , Amido , Difração de Raios X , Manihot/química , Amido/química , Ácidos Láuricos/química , Ácidos Graxos/química , Ácidos Decanoicos/química , Reologia , Caprilatos/química , Espectroscopia de Ressonância Magnética
5.
Food Res Int ; 187: 114425, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763673

RESUMO

In this study, composite gel was prepared from konjac glucomannan (KGM) and fibrin (FN). Composite gels with different concentration ratios were compared in terms of their mechanical properties, rheological properties, water retention, degradation rate, microstructure and biocompatibility. The results showed that the composite gels had better gel strength and other properties than non-composite gels. In particular, composite hydrogels with low Young's modulus formed when the KGM concentration was 0.8% and the FN concentration was 1.2%. The two components were cross linked through hydrogen-bond interaction, which formed a more stable gel structure with excellent water retention and in-vitro degradation rates, which were conducive to myogenic differentiation of ectomesenchymal stem cells (EMSCs). KGM-FN composite gel was applied to the preparation of cell-culture meat, which had similar texture properties and main nutrients to animal meat as well as higher content of dry base protein and dry base carbohydrate.


Assuntos
Fibrina , Hidrogéis , Mananas , Reologia , Mananas/química , Hidrogéis/química , Fibrina/química , Animais , Alicerces Teciduais/química , Células-Tronco Mesenquimais , Carne , Diferenciação Celular , Módulo de Elasticidade , Técnicas de Cultura de Células
6.
Food Res Int ; 187: 114418, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763668

RESUMO

Interest in exploring alternative starch sources like finger millet is rising due to wide starch applications. However, native starch often lacks desired qualities, including rheological properties. Modification is thus necessary for specific end uses. Plasma treatment as a greener and sustainable method for starch modification was therefore, studied for its ability to impact rheological properties of finger millet starch (FMS). Considerable changes in the rheological properties on FMS was noted, a significant decrease and increase (p < 0.05) in the peak viscosity (from 3.35 to 0.553 Pa.s) and paste clarity respectively was observed, indicating occurrence of depolymerization. However, intermediate plasma-treated samples (200 V) observed a decrease in paste clarity attributed to aggregate formation and cross-linking. Cross-linking was also confirmed by findings of frequency sweep where a continuous decrease in G' values of plasma treated FMS gel was interrupted by sudden increase. Despite depolymerization causing alteration of rheological behaviour such as decrease in shear thinning properties, gel strength observed a contradictory increase. This was attributed to incorporation of functional group and absence of shear responsible for network formation giving higher gel strength to FMS gels. This is elaborated in detail in the study. The study thus concluded that cold plasma significantly impacted all the rheological properties of the FMS and hence can prove to be beneficial for modification of starch rheological parameters.


Assuntos
Eleusine , Géis , Gases em Plasma , Reologia , Amido , Amido/química , Gases em Plasma/química , Viscosidade , Eleusine/química , Géis/química , Pressão Atmosférica , Manipulação de Alimentos/métodos
7.
Food Res Int ; 187: 114432, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763680

RESUMO

Probiotics are subjected to various edible coatings, especially proteins and polysaccharides, which serve as the predominant wall materials, with ultrasound, a sustainable green technology. Herein, sodium caseinate, inulin, and soy protein isolate composites were produced using multi-frequency ultrasound and utilized to encapsulateLactiplantibacillus plantarumto enhance its storage, thermal, and gastrointestinal viability. The physicochemical analyses revealed that the composites with 5 % soy protein isolate treated with ultrasound at 50 kHz exhibited enough repulsion forces to maintain stability, pH resistance, and the ability to encapsulate larger particles and possessed the highest encapsulation efficiency (95.95 %). The structural analyses showed changes in the composite structure at CC, CH, CO, and amino acid residual levels. Rheology, texture, and water-holding capacity demonstrated the production of soft hydrogels with mild chewing and gummy properties, carried the microcapsules without coagulation or sedimentation. Moreover, the viability attributes ofL. plantarumevinced superior encapsulation, protecting them for at least eight weeks and against heat (63 °C), reactive oxidative species (H2O2), and GI conditions.


Assuntos
Carboximetilcelulose Sódica , Caseínas , Hidrogéis , Inulina , Probióticos , Proteínas de Soja , Proteínas de Soja/química , Hidrogéis/química , Caseínas/química , Carboximetilcelulose Sódica/química , Inulina/química , Inulina/farmacologia , Lactobacillus plantarum/metabolismo , Reologia , Concentração de Íons de Hidrogênio , Viabilidade Microbiana , Cápsulas
8.
Food Res Int ; 187: 114430, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763679

RESUMO

Oleogels have been explored as fat substitutes due to their healthier composition compared to trans and saturated fats, also presenting interesting technological perspectives. The aim of this study was to investigate the compositional perspective of multicomponent oleogels. Structuring ability of lecithin (LEC) (20 or 90 wt% of phosphatidylcholine - PC) combined with glycerol monostearate (GMS), sorbitan monostearate (SMS) or sucrose monostearate (SAC) in sunflower oil was evaluated from oleogels properties. The thermal and rheological properties, microstructure and stability of the oleogels were affected by the difference in the chemical composition of LEC and the ratio between LEC and different surfactants. Interestingly, low-phosphatidylcholine LEC (L20) performed better, although systems formed with reduced amounts of LEC tended to be softer (LEC-GMS) and present high oil holding capacity (LEC-SMS). The mixtures of LEC and monostearate-based surfactants showed different behaviors, depending on the surfactant polar head. In LEC-GMS systems, LEC hindered the self-assembly of GMS in sunflower oil, compromising mechanical properties and increasing oil release. When combined with SMS, LEC acted as a crystal habit modifier of SMS, forming a more homogeneous microstructure and producing stronger oleogels with greater oil binding capacity. However, above the threshold concentration, LEC prevented SMS self-assembly, resulting in a weaker gel. A positive interaction was found in LEC-SAC formulations in specific ratios, since SAC cannot act as a single oleogelator. Results show the impact of solubility balance played by LEC and fatty-acid derivatives surfactant when combined and used as oleogelators. This knowledge can contribute to a rational perspective in the preparation and modulation of the properties of edible oleogels.


Assuntos
Lecitinas , Compostos Orgânicos , Reologia , Óleo de Girassol , Tensoativos , Lecitinas/química , Compostos Orgânicos/química , Óleo de Girassol/química , Tensoativos/química , Hexoses/química , Substitutos da Gordura/química , Glicerídeos/química , Sacarose/química
9.
Carbohydr Polym ; 338: 122213, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38763715

RESUMO

The present research studies the impact of apparent amylose content (AAC) on the quality of fortified rice kernels (FRK), a health food designed to combat iron deficiency anemia by fortifying with iron, folic acid, and vitamin B12. Five FRK formulations with varying AAC (0.46-23.89 %) were prepared, and AAC influence on the extruder-system parameter and physicochemical, cooking, and textural properties of FRK was investigated. The torque, die-pressure, length, redness, and cooking time increased with an increase in AAC and were in the range of 12.55-22.81 Nm, 58.31-88.96 bar, 4.58-5.09 mm, 0.35-1.15, and 6.1-11.2 min, respectively. The other parameters, such as the breadth, whiteness index, and cooking loss decreased with an increase in AAC. Except for cohesiveness, all other textural properties of cooked FRK increased with an increase in AAC. These correlations of the FRK properties with AAC were confirmed through multivariate analysis. SEM, XRD, FTIR, and rheology supported the observed AAC trends in FRK properties. SEM showed a reduction in pores and cracks with an increase in AAC. The XRD and FTIR showed an increase in crystallinity with an increase in AAC due to better gelatinization leading to rapid retrogradation. This leads to better physical, cooking, and textural properties of FRK.


Assuntos
Amilose , Culinária , Oryza , Oryza/química , Amilose/análise , Amilose/química , Alimentos Fortificados/análise , Reologia
10.
Carbohydr Polym ; 338: 122172, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38763719

RESUMO

Polysaccharide-based hydrogels are promising for many biomedical applications including drug delivery, wound healing, and tissue engineering. We illustrate herein self-healing, injectable, fast-gelling hydrogels prepared from multi-reducing end polysaccharides, recently introduced by the Edgar group. Simple condensation of reducing ends from multi-reducing end alginate (M-Alg) with amines from polyethylene imine (PEI) in water affords a dynamic, hydrophilic polysaccharide network. Trace amounts of acetic acid can accelerate the gelation time from hours to seconds. The fast-gelation behavior is driven by rapid Schiff base formation and strong ionic interactions induced by acetic acid. A cantilever rheometer enables real-time monitoring of changes in viscoelastic properties during hydrogel formation. The reversible nature of these crosslinks (imine bonds, ionic interactions) provides a hydrogel with low toxicity in cell studies as well as self-healing and injectable properties. Therefore, the self-healing, injectable, and fast-gelling M-Alg/PEI hydrogel holds substantial promise for biomedical, agricultural, controlled release, and other applications.


Assuntos
Alginatos , Hidrogéis , Polissacarídeos , Alginatos/química , Hidrogéis/química , Hidrogéis/síntese química , Hidrogéis/farmacologia , Polissacarídeos/química , Polietilenoimina/química , Humanos , Reologia , Animais , Bases de Schiff/química , Injeções , Camundongos
11.
ACS Biomater Sci Eng ; 10(5): 3343-3354, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38695560

RESUMO

Moldable tissue-sealant hydrogels were developed herein by combining the yield stress fluidity of a Carbomer and in situ cross-linking of 3-arm PEG-thiol (PEG-SH) and 4-arm PEG-acrylate (PEG-AC). The Carbomer was mixed with each PEG oligomer to form two aqueous precursors: Carbomer/PEG-SH and Carbomer/PEG-AC. The two hydrogel precursors exhibited sufficient yield stress (>100 Pa) to prevent dripping from their placement on the tissue surface. Moreover, these hydrogel precursors exhibited rapid restructuring when the shear strain was repeatedly changed. These rheological properties contribute to the moldability of these hydrogel precursors. After mixing these two precursors, they were converted from yield-stress fluids to chemically cross-linked hydrogels, Carbomer/PEG hydrogel, via thiol-Michael addition. The gelation time was 5.0 and 11.2 min at 37 and 25 °C, respectively. In addition, the Carbomer/PEG hydrogels exhibited higher cellular viability than the pure Carbomer. They also showed stable adhesiveness and burst pressure resistance to various tissues, such as the skin, stomach, colon, and cecum of pigs. The hydrogels showed excellent tissue sealing in a cecum ligation and puncture model in mice and improved the survival rate due to their tissue adhesiveness and biocompatibility. The Carbomer/PEG hydrogel is a potential biocompatible tissue sealant that surgeons can mold. It was revealed that the combination of in situ cross-linkable PEG oligomers and yield stress fluid such as Carbomer is effective for developing the moldable tissue sealant without dripping of its hydrogel precursors.


Assuntos
Hidrogéis , Polietilenoglicóis , Compostos de Sulfidrila , Hidrogéis/química , Hidrogéis/farmacologia , Polietilenoglicóis/química , Animais , Camundongos , Compostos de Sulfidrila/química , Adesivos Teciduais/química , Adesivos Teciduais/farmacologia , Suínos , Reagentes de Ligações Cruzadas/química , Reologia , Humanos , Resinas Acrílicas
12.
Int J Mol Sci ; 25(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731902

RESUMO

Investigation of chiroptical polymers in the solution phase is paramount for designing supramolecular architectures for photonic or biomedical devices. This work is devoted to the case study of poly(propylene oxide) (PPO) optical activity in several solvents: benzonitrile, carbon disulfide, chloroform, ethyl acetate, and p-dioxane. To attain information on the interactions in these systems, rheological testing was undertaken, showing distinct variations of the rheological parameters as a function of the solvent type. These aspects are also reflected in the refractive index dispersive behavior, from which linear and non-linear optical properties are extracted. To determine the circular birefringence and specific rotation of the PPO solutions, the alternative method of the channeled spectra was employed. The spectral data were correlated with the molecular modeling of the PPO structural unit in the selected solvents. Density functional theory (DFT) computational data indicated that the torsional potential energy-related to the O1-C2-C3-O4 dihedral angle from the polymer repeating unit-was hindered in solvation environments characterized by high polarity and the ability to interact via hydrogen bonding. This was in agreement with the optical characterization of the samples, which indicated a lower circular birefringence and specific rotation for the solutions of PPO in ethyl acetate and p-dioxane. Also, the shape of optical rotatory dispersion curves was slightly modified for PPO in these solvents compared with the other ones.


Assuntos
Solventes , Solventes/química , Propilenoglicóis/química , Polipropilenos/química , Polímeros/química , Modelos Moleculares , Rotação , Ligação de Hidrogênio , Reologia
13.
Carbohydr Polym ; 337: 122187, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710543

RESUMO

The effects of different electron beam irradiation doses (2, 4, 8 KGy) and various types of fatty acids (lauric acid, stearic acid, and oleic acid) on the formation, structure, physicochemical properties, and digestibility of starch-lipid complex were investigated. The complexing index of the complexes was higher than 85 %, indicating that the three fatty acids could easily form complexes with starch. With the increase of electron beam irradiation dose, the complexing index increased first and then decreased. The highest complexing index was lauric acid (97.12 %), stearic acid (96.80 %), and oleic acid (97.51 %) at 2 KGy radiation dose, respectively. Moreover, the microstructure, crystal structure, thermal stability, rheological properties, and starch solubility were analyzed. In vitro digestibility tests showed that adding fatty acids could reduce the content of hydrolyzed starch, among which the resistant starch content of the starch-oleic acid complex was the highest (54.26 %). The lower dose of electron beam irradiation could decrease the digestibility of starch and increase the content of resistant starch.


Assuntos
Elétrons , Ácidos Graxos , Solubilidade , Amido , Amido/química , Ácidos Graxos/química , Ácidos Láuricos/química , Reologia , Hidrólise , Ácido Oleico/química , Lipídeos/química
14.
J Biomed Mater Res B Appl Biomater ; 112(5): e35405, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38701384

RESUMO

The structure and handling properties of a P407 hydrogel-based bone substitute material (BSM) might be affected by different poloxamer P407 and silicon dioxide (SiO2) concentrations. The study aimed to compare the mechanical properties and biological parameters (bone remodeling, BSM degradation) of a hydroxyapatite: silica (HA)-based BSM with various P407 hydrogels in vitro and in an in vivo rat model. Rheological analyses for mechanical properties were performed on one BSM with an SiO2-enriched hydrogel (SPH25) as well on two BSMs with unaltered hydrogels in different gel concentrations (PH25 and PH30). Furthermore, the solubility of all BSMs were tested. In addition, 30 male Wistar rats underwent surgical creation of a well-defined bone defect in the tibia. Defects were filled randomly with PH30 (n = 15) or SPH25 (n = 15). Animals were sacrificed after 12 (n = 5 each), 21 (n = 5 each), and 63 days (n = 5 each). Histological evaluation and histomorphometrical quantification of new bone formation (NB;%), residual BSM (rBSM;%), and soft tissue (ST;%) was conducted. Rheological tests showed an increased viscosity and lower solubility of SPH when compared with the other hydrogels. Histomorphometric analyses in cancellous bone showed a decrease of ST in PH30 (p = .003) and an increase of NB (PH30: p = .001; SPH: p = .014) over time. A comparison of both BSMs revealed no significant differences. The addition of SiO2 to a P407 hydrogel-based hydroxyapatite BSM improves its mechanical stability (viscosity, solubility) while showing similar in vivo healing properties compared to PH30. Additionally, the SiO2-enrichment allows a reduction of poloxamer ratio in the hydrogel without impairing the material properties.


Assuntos
Substitutos Ósseos , Durapatita , Hidrogéis , Poloxâmero , Ratos Wistar , Dióxido de Silício , Animais , Masculino , Poloxâmero/química , Poloxâmero/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Durapatita/química , Durapatita/farmacologia , Dióxido de Silício/química , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Ratos , Teste de Materiais , Reologia , Tíbia/metabolismo
15.
PLoS One ; 19(5): e0303199, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38723048

RESUMO

This paper presents an optimized preparation process for external ointment using the Definitive Screening Design (DSD) method. The ointment is a Traditional Chinese Medicine (TCM) formula developed by Professor WYH, a renowned TCM practitioner in Jiangsu Province, China, known for its proven clinical efficacy. In this study, a stepwise regression model was employed to analyze the relationship between key process factors (such as mixing speed and time) and rheological parameters. Machine learning techniques, including Monte Carlo simulation, decision tree analysis, and Gaussian process, were used for parameter optimization. Through rigorous experimentation and verification, we have successfully identified the optimal preparation process for WYH ointment. The optimized parameters included drug ratio of 24.5%, mixing time of 8 min, mixing speed of 1175 rpm, petroleum dosage of 79 g, liquid paraffin dosage of 6.7 g. The final ointment formulation was prepared using method B. This research not only contributes to the optimization of the WYH ointment preparation process but also provides valuable insights and practical guidance for designing the preparation processes of other TCM ointments. This advanced DSD method enhances the screening approach for identifying the best preparation process, thereby improving the scientific rigor and quality of TCM ointment preparation processes.


Assuntos
Aprendizado de Máquina , Pomadas , Reologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/administração & dosagem , Medicina Tradicional Chinesa , Composição de Medicamentos/métodos , Dodecilsulfato de Sódio/química , Método de Monte Carlo
16.
Sci Rep ; 14(1): 11454, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769105

RESUMO

This study focuses on pectin covalently linked in cell walls from two sources, apples and carrots, that was extracted using diluted alkali, and it describes changes in the rheological properties of diluted alkali-soluble pectin (DASP) due to enzymatic treatment. Given DASP's richness of rhamnogalacturonan I (RG-I), RG-I acetyl esterase (RGAE), rhamnogalacturonan endolyase (RGL), and arabinofuranosidase (ABF) were employed in various combinations for targeted degradation of RG-I pectin chains. Enzymatic degradations were followed by structural studies of pectin molecules using atomic force microscopy (AFM) as well as measurements of rheological and spectral properties. AFM imaging revealed a significant increase in the length of branched molecules after incubation with ABF, suggesting that arabinose side chains limit RG-I aggregation. Structural modifications were confirmed by changes in the intensity of bands in the pectin fingerprint and anomeric region on Fourier transform infrared spectra. ABF treatment led to a decrease in the stability of pectic gels, while the simultaneous use of ABF, RGAE, and RGL enzymes did not increase the degree of aggregation compared to the control sample. These findings suggest that the association of pectin chains within the DASP fraction may rely significantly on intermolecular interactions. Two mechanisms are proposed, which involve side chains as short-range attachment points or an extended linear homogalacturonan conformation favoring inter-chain interactions over self-association.


Assuntos
Pectinas , Reologia , Pectinas/química , Pectinas/metabolismo , Microscopia de Força Atômica , Álcalis/química , Glicosídeo Hidrolases/metabolismo , Glicosídeo Hidrolases/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Daucus carota/química , Polissacarídeo-Liases/metabolismo , Polissacarídeo-Liases/química , Parede Celular/química , Parede Celular/metabolismo
17.
J Microencapsul ; 41(4): 296-311, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38709162

RESUMO

AIMS: To construct the microemulsion delivery system (ME) loading ATSO and NA and study their physicochemical characteristics to enhance their stability and water solubility. METHODS: By plotting ternary phase diagrams, the composition and proportions of the MEs were determined. The physicochemical characteristics and stability of MEs were evaluated by mean diameter, polydispersity index (PDI), pH, electrical conductivity, transmission electron microscopy (TEM), rheological behaviour measurement, and phase inversion temperature (PIT). RESULTS: The MEs was composed with EL-40 as a surfactant and specifically with the addition of ethanol as a cosurfactant in NA-loaded ME. The mean diameters of ATSO-loaded ME and NA-loaded ME were 39.65 ± 0.24 nm and 32.90 ± 2.65 nm, and PDI were 0.49 ± 0.01 and 0.28 ± 0.14, respectively. The TEM confirmed the spherical and smooth morphology of MEs. The rheological results indicated that MEs are dilatant fluids with the advantages of low viscosity, high fluidity, and tolerance to temperature fluctuations. The mean diameter and PDI of MEs showed no significant change after storage at 25 °C for 28 days and centrifugation. CONCLUSION: The prepared microemulsions could expand the application prospects of ATSO and NA products in cosmetics, medicine, foods and other fields.


Assuntos
Emulsões , Óleos de Plantas , Reologia , Emulsões/química , Óleos de Plantas/química , Acer/química , Ácidos Graxos/química , Sementes/química , Tensoativos/química , Estabilidade de Medicamentos , Viscosidade
18.
Sci Adv ; 10(19): eadl1586, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38718128

RESUMO

Viscoelastic transformation of tissue drives aberrant cellular functions and is an early biomarker of disease pathogenesis. Tissues scale a range of viscoelastic moduli, from biofluids to bone. Moreover, viscoelastic behavior is governed by the frequency at which tissue is probed, yielding distinct viscous and elastic responses modulated over a wide frequency band. Existing tools do not quantify wideband viscoelastic spectra in tissues, leaving a vast knowledge gap. We present wideband laser speckle rheological microscopy (WB-SHEAR) that reveals elastic and viscous response over sub-megahertz frequencies previously not investigated in tissue. WB-SHEAR uses an optical, noncontact approach to quantify wideband viscoelastic spectra in specimens spanning a range of moduli from low-viscosity fibrin to highly elastic bone. Via laser scanning, micromechanical imaging is enabled to access wideband viscoelastic spectra in heterogeneous tumor specimens with high spatial resolution (25 micrometers). The ability to interrogate the viscoelastic landscape of diverse biospecimens could transform our understanding of mechanobiological processes in various diseases.


Assuntos
Elasticidade , Reologia , Viscosidade , Reologia/métodos , Humanos , Animais , Lasers , Microscopia/métodos
19.
Anim Sci J ; 95(1): e13950, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38712489

RESUMO

The utilization of polyphenol-modified starch in ruminants has not undergone extensive exploration. This study aimed to investigate the impact of the complex formed between starch and Melastoma candidum D. Don fruit extract on physicochemical properties, phenol release kinetics in various buffers simulating the gastrointestinal tract, methane production, and post-rumen digestibility. The interaction between starch and M. candidum D. Don fruit extract significantly (p < 0.001) increased resistant starch and particle size diameter. The maximum phenolic release from complex between starch and M. candidum D. Don fruit extract, due to gastrointestinal tract-simulated buffers, ranged from 22.96 to 34.60 mg/100 mg tannic acid equivalent. However, rumen and abomasum-simulated buffers released more phenolic content, whereas the intestine-simulated buffer showed higher antioxidant activity (ferric ion-reducing antioxidant power). Furthermore, complex between starch and M. candidum D. Don fruit extract significantly decreased dry matter rumen digestibility (p < 0.001) and maximum methane gas production (p < 0.001).


Assuntos
Antioxidantes , Fenômenos Químicos , Digestão , Fermentação , Melastomataceae , Extratos Vegetais , Rúmen , Amido , Rúmen/metabolismo , Animais , Amido/metabolismo , Antioxidantes/metabolismo , Melastomataceae/química , Melastomataceae/metabolismo , Reologia , Metano/metabolismo , Frutas/química , Técnicas In Vitro , Fenóis/metabolismo , Fenóis/análise , Tamanho da Partícula , Polifenóis/metabolismo
20.
Int J Biol Macromol ; 265(Pt 2): 131159, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38565484

RESUMO

A goal of this study is to explore the difference in rheological properties of xanthan gum (XG)-based mixtures with gum arabic (GA) or GA-based emulsion (GAE). The stability of GAE was improved by thickening with XG. The intrinsic viscosity of all mixtures decreased as GA concentration increased, implying an XG conformational transition from the disordered to the ordered form. All mixtures except for an XG-GA mixture at 6.0 % GA attained a higher consistency index value than XG alone, indicating synergistic interactions between the components. At a high GA concentration (>3.0 %), the XG-GAE mixture showed higher relative apparent viscosity values than the XG-GA mixture. All mixtures except for an XG-GA mixture at 6.0 % GA showed higher elastic modulus and lower viscous modulus values than XG alone. Consequently, all mixtures showed lower tan δ values (0.26-0.30) than XG alone (0.31). Moreover, with a high GA concentration (>1.5 %), the XG-GAE mixtures achieved lower relative tan δ values than XG-GA mixture. These results indicate that XG formed a higher weak gel-like network with GAE than GA. Overall, the findings demonstrate that the interaction between XG and GA is influenced by conformational changes in the latter in both aqueous and emulsion systems.


Assuntos
Goma Arábica , Gomas Vegetais , Emulsões , Polissacarídeos Bacterianos , Viscosidade , Reologia/métodos
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