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1.
Polymers (Basel) ; 16(17)2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39274114

RESUMEN

In the 19th century, the weighting of silk with metal salts, such as tin, was a common practice to enhance certain properties of silk fabrics and compensate for the weight loss incurred during the degumming process. This technique induces both physical and chemical modifications to the fibres, contributing to their long-term degradation, which requires thorough investigation. This study aims to examine the structural changes in silk fibres caused by the accumulation of metal salts from the tin-weighting process, using mock-up samples prepared through successive loading with weighting agents using a traditional tin-phosphate treatment method. Unweighted and tin-weighted silk samples were compared using scanning electron (SEM) micrographs, which presented the dispersed nanoparticles on the fibres, while through energy-dispersive X-ray spectroscopy (EDS) elemental mapping, the presence and uniform distribution of the weighting agents were confirmed. Fourier-transform infrared spectroscopy (FTIR) analysis revealed structural changes in tin-weighted silk samples compared to untreated ones, including shifts in amide bands, altered water/hydroxyl and skeletal stretching regions, and increased skeletal band intensities suggesting modifications in hydrogen bonding, ß-sheet content, and structural disorder without significantly impacting the overall crystallinity index. X-ray diffraction (XRD) analysis of both pristine and tin-weighted silk samples revealed significant alterations, predominantly in the amorphous regions of the silk upon weighting. These structural changes were further examined using small-angle X-ray scattering (SAXS) and small- and wide-angle X-ray scattering (SWAXS), which provided detailed insights into modifications occurring at the nanometre scale. The analyses suggested disruptions in ß-sheet crystals and intermolecular packing, especially in the amorphous regions, with increasing amounts of tin-weighting. Contact angle analysis (CA) revealed that the tin-phosphate-weighting process significantly impacted silk surface properties, transforming it from moderately hydrophobic to highly hydrophilic. These changes indicate that the incorporation of tin-phosphate nanoparticles on and within silk fibres could restrict the flexibility of polymer chains, impacting the physical properties and potentially the degradation behaviour of silk textiles. By studying these structural changes, we aim to deepen our understanding of how tin-weighting impacts silk fibre structure, contributing valuable insights into the longevity, conservation, and preservation strategies of silk textiles in the context of cultural heritage.

2.
Food Chem ; 463(Pt 1): 141042, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39241412

RESUMEN

Textured vegetable proteins (TVP) are an alternative to meet the increasing demand for non-animal food. This study aimed to develop a TVP from mixtures with 45 % pea protein isolate (PPI) enriched with amaranth (AF) and oat (OF) flours using high-moisture extrusion technology (HME) varying the moisture (50-70 %) and the temperature in the second heating zone of the extruder (110-140 °C). After extrusion, all samples demonstrated higher values of water absorption capacity (WAC) than non-extruded mixtures. Mixture of AF:OF:PPI (40:15:45 %) extruded at 60 % moisture and 135 °C showed promising functional properties with WAC and WSI values of 3.2 ± 0.2 g H2O/g and 24.89 ± 2.31 %, respectively, and oil absorption capacity (OAC) of 1.3 g oil/g. The extrusion process altered the thermal and structural properties of proteins promoting a desirable fibrous structure. This confirms the feasibility of using HME to develop TVP based on PPI, AF, and OF.

3.
Beyoglu Eye J ; 9(3): 120-127, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39239624

RESUMEN

Objectives: To evaluate the long-term structural changes of the anterior chamber (AC) angle following gonioscopy-assisted transluminal trabeculotomy (GATT). Methods: The AC angle of 10 eyes that underwent GATT at least 6 years previously was assessed for structural changes. A detailed gonioscopy was performed to determine the state of the cleft and the position of the trabecular flap. An anterior segment optical coherence tomography (AS-OCT) examination was performed on the corresponding areas on gonioscopy. Results: The typical finding of the angle following GATT was an open cleft with a visible trabecular flap. However, the gonioscopy of our patients revealed three different cleft appearances: open, closed, and segmentally open cleft. In the long-term, the trabecular flap re-approximated the incision site in some areas resulting in the appearance of a closed cleft on gonioscopy. On AS-OCT the cleft was identified when the lumen of Schlemm's canal was connected to the AC, while the position of the flap differed. The cleft was observed as open in median 4.0 (IQR: 2.8-6.0) clock hours. The cleft was found open mostly in the superior quadrants of the angle (nine eyes). No correlation was found between the extent of open cleft and the percentage of IOP reduction. Conclusion: AS-OCT, when used in conjunction with gonioscopy, was found helpful to evaluate the structural changes following GATT. As observed in the study, the cleft tended to close in some areas. It was found preserved mostly in the superior half of the angle in the long term.

4.
Ital J Pediatr ; 50(1): 189, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39300569

RESUMEN

BACKGROUND: Neurocognitive disorders frequently occur in patients with cyanotic congenital heart disease (CCHD) because of the hemodynamic abnormalities induced by preoperative cardiac structural changes. We aimed to evaluate subcortical nuclei volume changes and cognition in postoperative tetralogy of Fallot (TOF) children, and analyze their relationship with preoperative cardiac structural changes. METHODS: This case-control study involved thirty-six children with repaired TOF and twenty-nine healthy controls (HCs). We utilized three-dimensional (3D) T1-weighted high-resolution structural images alongside the Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition (WPPSI-IV) to evaluate the cognitive differences between the TOF and HC group. RESULTS: We observed notable differences in subcortical nuclei volume between the TOF and HC group, specifically in the left amygdala nucleus (LAM, TOF: 1292.60 ± 155.57; HC: 1436.27 ± 140.62, p < 0.001), left thalamus proper nucleus (LTHA, TOF: 6771.54 ± 666.03; HC: 7435.36 ± 532.84, p < 0.001), and right thalamus proper nucleus (RTHA, TOF: 6514.61 ± 715.23; HC: 7162.94 ± 554.60, p < 0.001). Furthermore, a diminished integrity of LAM ( ß:-19.828, 95% CI: -36.462, -3.193), which showed an inverse relationship with the size of the preoperative ventricular septal defect (VSD), correlated with lower working memory indices in children with TOF. CONCLUSIONS: Our findings indicate that subcortical nuclei structural injuries possibly potentially stemming from cardiac anatomical abnormalities, are associated with impaired working memory in preschool-aged children with TOF. The LAM in particular may serve as a potential biomarker for neurocognitive deficits in TOF, offering predictive value for future neurodevelopmental outcomes, and shedding light on the neurophysiological mechanisms of these cognitive impairments.


Asunto(s)
Tetralogía de Fallot , Humanos , Tetralogía de Fallot/cirugía , Preescolar , Femenino , Masculino , Estudios Transversales , Estudios de Casos y Controles , Imagen por Resonancia Magnética , Cognición/fisiología , Procedimientos Quirúrgicos Cardíacos , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/patología
5.
Artículo en Inglés | MEDLINE | ID: mdl-39298018

RESUMEN

The incidence of diabetic cardiomyopathy (DCM) significantly increases in postmenopausal women, suggesting protective roles of estrogen. Excessive endoplasmic reticulum (ER) stress alters myocardial structure, which plays a crucial role in DCM. The G protein-coupled estrogen receptor (GPER) has been demonstrated to have cardioprotective effects, but it remains unclear whether these effects involve the amelioration of structural changes induced by ER stress. The objective of this study was to determine whether GPER can prevent cardiac structural changes by attenuating ER stress. Female ovariectomized (OVX) rats were divided into three groups: OVX, OVX + T2D, and OVX + T2D + G1. T2D was induced by a high-fat diet, and streptozotocin and G1, a GPER agonist, were administered for 6 weeks. Finally, histological changes of the myocardium were examined and the expression of sarcoplasmic reticulum calcium ATPase (SERCA2α), GRP78 as an ER stress marker, and apoptotic signalings were determined by Western blot. We observed that the induction of T2D resulted in an increased cardiac weight index, left ventricular wall thickness, and myocyte diameter. However, GPER activation reversed these changes. T2D increased cardiac protein levels of GRP78, caspase-12, and Bax, while decreasing levels of SERCA2α and Bcl-2. Nevertheless, GPER activation reduced the expression of GRP78 in OVX + T2D rats. Furthermore, GPER activation significantly reduced cardiac caspase-12 and Bax levels and increased SERCA2α and Bcl-2 expression. In conclusion, our data suggest that GPER activation ameliorates DCM by inhibiting ER stress-induced cardiac structural changes. These findings provide a new potential target for therapeutic intervention and drug discovery specifically tailored for postmenopausal diabetic women.

6.
Cephalalgia ; 44(9): 3331024241266951, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39238475

RESUMEN

BACKGROUND: Recent studies suggested that persons with migraine might be at higher risk of structural brain changes, including cerebral small vessel disease and atrophy. However, findings in the literature are inconsistent, with variations observed in the direction, magnitude, and population characteristics of reported effects, and large-scale population-based evidence remains scarce. Hence, we investigated the association of migraine with structural brain changes in a middle-aged and elderly population. METHODS: Within the population-based Rotterdam Study, lifetime history of migraine was assessed using a validated questionnaire between 2006 and 2011. Magnetic resonance imaging of the brain was performed in 4920 participants (median age 61.7 [IQR 45.5, 97.5] years, 55.4% female) to assess imaging markers of cerebral small vessel disease and brain atrophy. We used linear and logistic regression models to examine the cross-sectional association of migraine with brain volumes (total grey and white matter volumes in mL) and cerebral small vessel disease markers (white matter hyperintensity volume in mL, presence of lacunes and cerebral microbleeds). Adjustments were made for age, sex, intracranial volume and cardiovascular variables. Analyses were also stratified by sex and presence of aura. RESULTS: The lifetime prevalence of migraine was 15.3% (752/4920). In multivariable adjusted regression models, we found no statistically significant differences between participants with and without migraine in terms of total brain volume (mean difference [MD]: 2.21 mL, 95% confidence interval [CI]: -0.38 ; 4.81), grey matter volume (MD: 0.38 mL, 95% CI: -1.98 ; 2.74), white matter volume (MD: 2.19 mL, 95% CI: -0.56 ; 4.93), log white matter hyperintensity volume (MD: -0.04 mL, 95% CI: -0.10 ; 0.02), presence of lacunes (odds ratio [OR]: 0.82, 95% CI: 0.58-1.15), and presence of cerebral microbleeds (OR: 0.95, 95% CI: 0.76-1.18). CONCLUSION: In this study, we found that middle-aged and elderly participants with migraine were not more likely to have structural brain changes on magnetic resonance imaging.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Trastornos Migrañosos , Humanos , Femenino , Masculino , Trastornos Migrañosos/epidemiología , Trastornos Migrañosos/patología , Trastornos Migrañosos/diagnóstico por imagen , Persona de Mediana Edad , Anciano , Encéfalo/patología , Encéfalo/diagnóstico por imagen , Enfermedades de los Pequeños Vasos Cerebrales/epidemiología , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Enfermedades de los Pequeños Vasos Cerebrales/patología , Países Bajos/epidemiología , Estudios Transversales , Atrofia/patología , Anciano de 80 o más Años , Estudios de Cohortes , Estudios Prospectivos
7.
Meat Sci ; 217: 109616, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39089087

RESUMEN

Fat greatly impacts the overall texture and flavor of pork belly. Twice-cooked pork bellies (TPB), typically boiled and sliced before "back to pot" being stir-fried, is a classic Sichuan cuisine among stir-fried dishes. In this study, the effects of substituting conventional pan-frying (PCV) with superheated steam (SHS) technology on the sensory, texture, microstructure and flavor of the fat layers were investigated. SHS was used as an alternative to boiling (120 °C for 15, 20, 25, and 30 min), and "back to pot" stir-frying was also by SHS. TPB precooked for 25 min (P25) with SHS performed better quality characteristics than PCV, with less collagen fiber disruption and lipid droplet area, resulting in a lower hardness and higher shear force. Besides, the low-oxygen environment of SHS retarded the lipid peroxidation, showing a significantly lower MDA content than PCV. Differently, PCV exhibited more grassy and fatty flavors, while P25 exhibited a unique aroma of fruity and creamy due to its higher UFA/SFA ratios in the pre-cooking stage. Overall, the sensory scores of P25 were comparable to those of PCV (with no significant difference), revealing that SHS is expected to be applied to the industrial production of stir-fried dishes.


Asunto(s)
Culinaria , Carne de Cerdo , Vapor , Culinaria/métodos , Calor , Peroxidación de Lípido , Carne de Cerdo/análisis , Gusto
8.
Ultrason Sonochem ; 110: 107044, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39186917

RESUMEN

Protein hydrolysates have attracted much attention for their high biological activity and are a crucial product form for the utilization of foxtail millet bran by-products. In this study, changes in the structure, functionality, activity and peptide profile of foxtail millet bran protein hydrolysates (FMBPHs) at different ultrasound powers (0 - 600 W) were investigated. The results showed that ultrasound promoted the transformation of α-helix and ß-sheet to random coils and ß-turn, and the exposure of hydrophobic groups and sulfhydryl groups in FMBPHs. The average particle size of the samples decreased, and the absolute value of the ζ-potential increased significantly. Simultaneously, smaller porous particles and loose fragments appeared on the surface of FMBPHs when the ultrasonic power was increased to 450 W. Additionally, 450 W ultrasound treatment improved solubility, foaming properties, emulsifying properties, thermal stability of FMBPHs. The DPPH, ABTS and hydroxyl radical scavenging ability (IC50, 2.65, 1.06 and 3.02 mg/mL), Fe2+ chelating activity (IC50, 2.62 mg/mL), and reducing power of the samples were also enhanced. The peptidomics results demonstrated that ultrasonication increased the number of active peptides in the hydrolysate, and the relative abundance of 17 active peptides was obviously elevated at 450 W. Peptide map analysis showed that ultrasound-induced structural modifications affected the peptide profiles of Ubiquitin-like domain-containing protein, Cupin type-1 domain-containing protein, 40S ribosomal protein S19, and Oleosin 1, showing changes in the abundance of certain peptides, which may be related to changes in the characterization of FMBPHs.


Asunto(s)
Proteínas de Plantas , Hidrolisados de Proteína , Setaria (Planta) , Setaria (Planta)/química , Hidrolisados de Proteína/química , Proteínas de Plantas/química , Ondas Ultrasónicas , Péptidos/química , Solubilidad , Hidrólisis , Antioxidantes/química , Proteómica/métodos
9.
J Environ Manage ; 367: 121958, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39094413

RESUMEN

One of the main current focuses of global economies and decision-makers is the efficiency of energy utilization in cryptocurrency mining and trading, along with the reduction of associated carbon emissions. Understanding the pattern of Bitcoin's energy consumption and its bubble frequency can greatly enhance policy analysis and decision-making for energy efficiency and carbon emission reduction. This research aims to assess the validity of the random walk hypothesis for Bitcoin's electricity consumption and carbon footprint. We employed both traditional methods (ADF and KPSS) and recently proposed unit root techniques that account for structural breaks and non-linearity in the data series. Our analysis covers daily data from July 2010 to December 2021. The empirical results revealed that traditional unit root techniques did not confirm the stationarity of both bitcoin's electricity consumption and carbon footprint. However, novel structural break (SB) and linearity tests conducted enabled us to discover five SB episodes between 2012 and 2020 and non-linearity of the variables, which informed our application of the newly developed non-linear unit root tests with structural breaks. With the new methods, the results indicated stationarity after accommodating the SB and non-linearity. Furthermore, based on Phillips and Shi (2019)'s test, we identified certain bubble episodes in the bitcoin energy and carbon variables between 2013 and 2021. The major drivers of the bubbles in bitcoin energy consumption and carbon footprint are variables relating to the bitcoin and financial markets activities and risks, including the global economic and political risks. The study's conclusion based on the above findings informs several policy implications drawn for energy and environmental management including the encouragement of green investments in cryptocurrency mining and trading.


Asunto(s)
Huella de Carbono , Electricidad , Carbono
10.
Brain Res ; 1844: 149150, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39127119

RESUMEN

Olfactory dysfunction is a common non-motor symptom of Parkinson's disease(PD) and may hold valuable insights into the disease's underlying pathophysiology. This study aimed to investigate cortical morphometry alterations in PD patients with severe hyposmia(PD-SH) and mild hyposmia(PD-MH) using surface-based morphometry(SBM) methods. Participants included 36 PD-SH patients, 38 PD-MH patients, and 40 healthy controls(HCs). SBM analysis revealed distinct patterns of cortical alterations in PD-SH and PD-MH patients. PD-MH patients exhibited reduced cortical thickness in the right supramarginal gyrus, while PD-SH patients showed widespread cortical thinning in regions including the bilateral pericalcarine cortex, bilateral lingual gyrus, left inferior parietal cortex, left lateral occipital cortex, right pars triangularis, right cuneus, and right superior parietal cortex. Moreover, PD-SH patients displayed reduced cortical thickness in the right precuneus compared to PD-MH patients. Fractal dimension analysis indicated increased cortical complexity in PD-MH patients' right superior temporal cortex and right supramarginal gyrus, as well as decreased complexity in the bilateral postcentral cortex, left superior parietal cortex, and right precentral cortex. Similarly, cortical gyrification index and cortical sulcal depth exhibited heterogeneous patterns of changes in PD-SH and PD-MH patients compared to HCs. These findings underscore the multifaceted nature of olfactory impairment in PD, with distinct patterns of cortical morphometry alterations associated with different degrees of hyposmia. The observed discrepancies in brain regions showing alterations reflect the complexity of PD's pathophysiology. These insights contribute to a deeper understanding of olfactory dysfunction in PD and provide potential avenues for early diagnosis and targeted interventions.


Asunto(s)
Anosmia , Corteza Cerebral , Imagen por Resonancia Magnética , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/patología , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico por imagen , Masculino , Femenino , Persona de Mediana Edad , Anciano , Corteza Cerebral/patología , Corteza Cerebral/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Anosmia/patología , Trastornos del Olfato/patología , Trastornos del Olfato/etiología , Trastornos del Olfato/diagnóstico por imagen , Trastornos del Olfato/fisiopatología
11.
Food Chem ; 458: 140265, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38968707

RESUMEN

The binding capacity of ß-Lactoglobulin (BLG) is crucial for delivering polyphenols, influenced by structural changes. High pressure processing (HPP) has the potential to modify BLG's structure and aggregation, but its specific impact on BLG-polyphenol interactions is uncertain. This study used circular dichroism spectroscopy and molecular dynamics simulations to reveal HPP-induced structural changes in BLG, supported by particle size analysis indicating aggregation. Seven structurally diverse polyphenols (quercetin-QR, hesperetin-HSP, dihydromyricetin-DHM, gallic acid-GA, (-)-epicatechin-EC, resveratrol-RES, and secoisolariciresinol diglucoside-SDG) were investigated to comprehensively analyze their binding patterns using fluorescence spectroscopy and molecular docking. HPP reduced BLG's ordered structure and increased its aggregation. Binding affinities peaked at 400 MPa for DHM, QR, HSP, GA, and RES, while SDG and EC exhibited maximum affinities at atmospheric pressure and 600 MPa, respectively. Elevated pressures enhanced BLG-polyphenol interactions, particularly at residues 44GLU and 160CYS, with van der Waals forces dominating the binding free energy.


Asunto(s)
Lactoglobulinas , Simulación del Acoplamiento Molecular , Polifenoles , Presión , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Polifenoles/química , Polifenoles/metabolismo , Unión Proteica , Simulación de Dinámica Molecular , Animales , Manipulación de Alimentos , Agregado de Proteínas , Bovinos
12.
Int J Biol Macromol ; 277(Pt 1): 134121, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39053821

RESUMEN

To investigate the mechanism of lignin degradation during sesame roasting, structural transformations of milled wood lignin (MWL) from sesame seed hull samples roasted at 190-250 °C for 30 min were investigated. The findings revealed that, with increasing temperature, the degradation extent of carbohydrates from lignin carbohydrate complex in the fractions deepened, which reduced total sugar content (from 8.59 % to 0.45 %). Compared to that of the original sesame seed hull lignin (LSSH), the molecular weight of MWL fractions showed a tendency to decline (Mw 4377-2235 Da) with the rise of roasting temperature (210-250 °C). During roasting, lignins in the sesame seed hull underwent degradation and condensation. Due to demethoxylation, the H-type lignin proportion increased from 2.7 % to 26.1 %. Compared to G- and C-type lignin, S-type lignin was more stable. The ß-O-4 linkages decreased from 5.8 to 1.2/100 Ar due to CO bond breaking, and ß-ß linkages from 26.3 to 9.6/100 Ar decreased due to condensation of CC. As the roasting temperature increased, more chemical bonds between lignin structural units were broken, resulting in the generation of more phenolic hydroxyl groups (1.80-2.53 mmol/g). This study helps to elucidate the contribution of lignin degradation during roasting to the oxidative stability of sesame oil.


Asunto(s)
Calor , Lignina , Semillas , Sesamum , Lignina/química , Sesamum/química , Semillas/química , Peso Molecular
13.
Radiol Clin North Am ; 62(5): 837-847, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39059975

RESUMEN

Imaging of rheumatologic diseases has historically been performed using conventional radiography. MRI offers an opportunity for detection of altered marrow signal in early disease that is not visible on other imaging modalities such as radiography, computed tomography, or sonography. This review describes the advantages of current MRI techniques in the diagnosis and treatment monitoring of rheumatologic diseases. In addition, this review discusses novel MRI techniques at high-field magnetic strength which may be deployed in the future to allow for improved imaging resolution and quantitative assessment of both axial and peripheral joints.


Asunto(s)
Imagen por Resonancia Magnética , Enfermedades Reumáticas , Humanos , Imagen por Resonancia Magnética/métodos , Enfermedades Reumáticas/diagnóstico por imagen , Reumatología/métodos
14.
Food Chem ; 457: 139924, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-38917563

RESUMEN

In the present study, we investigated the mechanisms associated with the stabilizing effects of whey protein concentrate-80 (WPC80) and L-ascorbyl 6-palmitate (LAP) on folic acid (FA). Multispectral techniques show that WPC80 binds to FA and LAP mainly through hydrophobic interactions, and that energy is transferred from WPC80 to FA and LAP in a nonradiative form (FA/LAP); The combination of FA/LAP resulted in a change in the conformation and secondary structure content of WPC80, an increase in the absolute zeta potential of the system, and a shift in the particle size distribution towards smaller sizes. The compound system exhibits strengthened antioxidant properties and favorable binding properties. Besides, WPC80 improves the storage stability of FA under different conditions. These results demonstrated that the ternary complex formed by FA co-binding with WPC80 and LAP is an effective way to improve the stability against of FA.


Asunto(s)
Ácido Ascórbico , Ácido Fólico , Proteína de Suero de Leche , Proteína de Suero de Leche/química , Ácido Fólico/química , Ácido Ascórbico/química , Ácido Ascórbico/análogos & derivados , Interacciones Hidrofóbicas e Hidrofílicas , Tamaño de la Partícula , Antioxidantes/química
15.
Food Res Int ; 188: 114466, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823863

RESUMEN

The effect of microfluidization treatment on the primary, secondary, and tertiary structure of soybean protein isolate (SPI) was investigated. The samples were treated with and without controlling the temperature and circulated in the system 1, 3, and 5 times at high pressure (137 MPa). Then, the treated samples were freeze-dried and reconstituted in water to check the impact of the microfluidization on two different states: powder and solution. Regarding the primary structure, the SDS-PAGE analysis under reducing conditions showed that the protein bands remained unchanged when exposed to microfluidization treatment. When the temperature was controlled for the samples in their powder state, a significant decrease in the quantities of ß-sheet and random coil and a slight reduction in α-helix content was noticed. The observed decrease in ß-sheet and the increase in ß-turns in treated samples indicated that microfluidization may lead to protein unfolding, opening the hydrophobic regions. Additionally, a lower amount of α-helix suggests a higher protein flexibility. After reconstitution in water, a significant difference was observed only in α-helix, ß-sheet and ß-turn. Related to the tertiary structure, microfluidization increases the surface hydrophobicity. Among all the conditions tested, the samples where the temperature is controlled seem the most suitable.


Asunto(s)
Manipulación de Alimentos , Interacciones Hidrofóbicas e Hidrofílicas , Polvos , Proteínas de Soja , Proteínas de Soja/química , Manipulación de Alimentos/métodos , Estructura Secundaria de Proteína , Temperatura , Proyectos Piloto , Electroforesis en Gel de Poliacrilamida , Glycine max/química , Soluciones , Liofilización
16.
Food Res Int ; 190: 114599, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38945569

RESUMEN

To investigate the morphological changes of insoluble fiber and their effects on microbiota modulation, particularly Bacteroides, rice bran insoluble fibers were extruded at different feed moisture levels (E20, E40, and E60). The physicochemical properties and SEM revealed that E20 exhibited the highest water holding capacity and displayed the most fragmented edges. E40 had the highest swelling holding capacity and displayed the most lamellar gaps. E60 showed minimal change in physicochemical properties but had a rough surface. After 48h fermentation, E40 showed the highest levels of Bacteroides and SCFAs. E20 and E60 resulted in a modest increase in Bacteroides abundance. SEM showed that bacteria were attached to fragmented edges, loosened lamellar gaps, and rough surfaces of the extruded insoluble fibers. The results suggested that Bacteroides gained a competitive advantage within the extrusion treatment created structural changes. Extrusion treatment can be used to generate specific niches favorable for Bacteroides.


Asunto(s)
Bacteroides , Fibras de la Dieta , Fermentación , Oryza , Oryza/microbiología , Bacteroides/metabolismo , Fibras de la Dieta/metabolismo , Ácidos Grasos Volátiles/metabolismo , Agua/química , Manipulación de Alimentos/métodos , Solubilidad
17.
Food Chem ; 454: 139742, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38795623

RESUMEN

This study investigated the effects of octenyl succinic anhydride (OSA)-starch-fatty acid (FA) interactions on the structural, digestibility and release characteristics of high amylose corn starch (HAS). FTIR and XRD analysis showed that the hydrophobic interaction between HAS and FA promoted the covalent binding between OSA and HAS. With the increasing of the FA chain length, the complex index, degree of substitution, R1047/1022 and relative crystallinity of OSA-HAS-FA increased first and then decreased, whereas the first-order rate coefficient and percentage of digested in infinite time showed an opposite trend. Structural changes and the molecular interactions of OSA-HAS-FA with 12­carbon FA resulted in highest resistant starch content (45.43%) and encapsulation efficiency of curcumin (Cur) (47.98%). In vitro release test revealed that Cur could be gradually released from OSA-HAS-FA in simulated gastric, intestinal and colonic fluids. Results provided novel insights into HAS-FA complex grafted with OSA as carrier for colon-specific of functional materials.


Asunto(s)
Amilosa , Digestión , Ácidos Grasos , Almidón , Zea mays , Amilosa/química , Amilosa/metabolismo , Almidón/química , Almidón/metabolismo , Almidón/análogos & derivados , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Zea mays/química , Zea mays/metabolismo , Anhídridos Succínicos/química , Humanos
18.
Sci Total Environ ; 934: 173133, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38734091

RESUMEN

The high use of plastic wraps leads to significant environmental pollution. In this study, the surface structure and microbial community evolution of commercially available plastic wraps [polyethylene (PE), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), and polylactic acid (PLA)] in constructed wetlands (CWs) were investigated. The results indicated that all plastic wraps gradually decreased in molecular weight, crystallinity, melting, and crystallization temperatures, whereas a gradual increase was observed in the surface roughness, polymer dispersity index (PDI), carbonyl index (CI) and Shannon index of microorganisms colonizing the CWs. The aging rate of the plastic wrap was in the order: PLA > PVC > PE > PVDC, at the same site in the CWs, and it was in the order: soil surface > plant roots > subsoil, for the same plastic wrap. The diversity of microorganisms colonizing the same plastic wrap was in the order: plant roots > subsoil > soil surface. The Shannon indices of microorganisms on plastic wraps were lower than those in the soil, indicating that the diversity of microorganisms colonizing plastic wraps is limited. Additionally, the microbial community structure on the plastic surface was co-differentiated by the plastic type, placement position in the CWs, and aging time. Significantly different microbial community structures were found on the PVC and PVDC wrap surfaces, revealing that the chlorine in plastics limits microbial diversity. Unclassified members of Rhizobiaceae and Pseudomonadaceae were the dominant genera on the surface of the plastic wraps, suggesting that they may be the microorganisms involved in plastic degradation processes. The study provides valuable perspectives to facilitate a comprehensive understanding of the migration, fate, and environmental risks associated with microplastics (MPs) in wetlands.


Asunto(s)
Microbiota , Plásticos , Humedales , Microbiología del Suelo , Contaminantes Químicos del Agua/análisis
19.
Small Methods ; : e2400084, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738733

RESUMEN

Doping plays a crucial role in modulating and enhancing the performance of organic semiconductor (OSC) devices. In this study, the critical role of dopants is underscored in shaping the morphology and structure of OSC films, which in turn profoundly influences their properties. Two dopants, trityl tetrakis(pentafluorophenyl) (TrTPFB) and N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate (DMA-TPFB), are examined for their doping effects on poly(3-hexylthiophene) (P3HT) and PBBT-2T host OSCs. It is found that although TrTPFB exhibits higher doping efficiency, OSCs doped with DMA-TPFB achieve comparable or even enhanced electrical conductivity. Indeed, the electrical conductivity of DMA-TPFB-doped P3HT reaches over 67 S cm-1, which is a record-high value for mixed-solution-doped P3HT. This can be attributed to DMA-TPFB inducing a higher degree of crystallinity and reduced structural disorder. Moreover, the beneficial impact of DMA-TPFB on the OSC films' morphology and structure results in superior thermoelectric performance in the doped OSCs. These findings highlight the significance of dopant-induced morphological and structural considerations in enhancing the film characteristics of OSCs, opening up a new avenue for optimization of dopant performance.

20.
Food Res Int ; 187: 114361, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38763645

RESUMEN

This work investigated the cryoprotective effect of trehalose (TH) and sodium pyrophosphate (SPP) alone and in combination on myofibrillar protein (MP) oxidation and structural changes in silver carp surimi during 90 days of frozen storage (-20 °C). TH combined with SPP was significantly more effective than single TH or SPP in preventing MP oxidation (P < 0.05), showing a higher SH content (6.05 nmol/mg protein), and a lower carbonyl (4.24 nmol/mg protein) and dityrosine content (1280 A.U.). SDS-PAGE results indicated that TH combined with SPP did not differ significantly from TH and SPP in inhibiting protein degradation but was more effective in inhibiting protein crosslinking. Moreover, all cryoprotectants could stabilise the secondary and tertiary structures and inhibit unfolded and aggregation of MP, with the combination of TH and SPP being the best. It's worth noting that TH combined with SPP had a synergistic effect on inhibiting the decrease in α-helix content and gel-forming ability, and the increase in surface hydrophobicity. Overall, TH combined with SPP could significantly inhibited MP oxidation and structural changes in surimi during frozen storage and improve the gel-forming ability, which was significantly better than single TH or SPP.


Asunto(s)
Carpas , Crioprotectores , Difosfatos , Almacenamiento de Alimentos , Congelación , Proteínas Musculares , Oxidación-Reducción , Trehalosa , Animales , Trehalosa/química , Almacenamiento de Alimentos/métodos , Difosfatos/química , Proteínas Musculares/química , Crioprotectores/química , Crioprotectores/farmacología , Proteínas de Peces/química , Conservación de Alimentos/métodos , Productos Pesqueros/análisis , Miofibrillas/química
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