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1.
Biofouling ; : 1-8, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39380146

RESUMEN

Microbiologically contaminated water is a significant source of infections in humans and animals, with Pseudomonas aeruginosa (PSA) being particularly concerning due to its ability to thrive in water environments and its resistance to many disinfectants. Therefore, this study investigates the adhesion potential of PSA strains on various materials used in mineral water extraction wells, focusing on hydrophobic and hydrophilic properties. Mineral water samples were collected from three wells (P-01, P-07, and P-08) within the Guarani Aquifer System and Fractured Aquifer System (SAF) in Brazil. The physicochemical properties of the water, including concentrations of Sr (strontium), Fe (iron), Si (silicon), SO42- (sulfate ions), Cl- (chloride ions), and ORP (oxidation-reduction potential), were analyzed. Results indicated higher PSA adhesion on hydrophobic materials, particularly high-density polyethylene (HDPE) and geomechanically plasticized polyvinyl chloride (PVC). Multiple correlation analyses revealed positive correlations between PSA adhesion on hydrophilic materials and Sr, Fe, Si, SO42-, and Cl- concentrations. Conversely, ORP negatively correlated with bacterial adhesion on PVC surfaces, suggesting higher ORP values reduced PSA attachment. These findings highlight the importance of water composition and material properties in influencing bacterial adhesion and potential biofilm formation in mineral water extraction systems.

2.
Clin Oral Investig ; 28(11): 578, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39377827

RESUMEN

OBJECTIVES: To analyze the incorporation of cardanol trimethacrylate monomer (CTMA), derived from the cashew nut shell liquid, as a substitute for Bis-GMA in acrylic resins formulations and its effect on experimental resin composites' physicochemical and mechanical properties. MATERIALS AND METHODS: The intermediary cardanol epoxy was synthesized via cardanol epoxidation, followed by the synthesis of CTMA through methacrylic anhydride solvent-free esterification. Experimental resin composites were formulated with an organic matrix composed of Bis-GMA/TEGDMA (50/50 wt %) (control). CTMA was gradually added to replace different proportions of Bis-GMA: 10 wt % (CTMA-10), 20 wt % (CTMA-20), 40 wt % (CTMA-40), and 50 wt % (CTMA-50). The composites were characterized by degree of conversion, water sorption and solubility, viscosity, thermogravimetric analysis, dynamic mechanical analysis, flexural strength and elastic modulus. Data were analyzed with one-way ANOVA and Tukey's post-hoc test (α = 0.05), except for water sorption data, which were analyzed by Kruskall-Wallis and Dunn's method. RESULTS: CTMA-based and control composites did not show statistically significant differences regarding degree of conversion, flexural strength and elastic modulus. CTMA reduced the viscosity and solubility compared to the Bis-GMA-based composite. The CTMA-40 and CTMA-50 exhibited significantly lower water sorption compared to the control. Also, acceptable thermal stability and viscoelastic properties were obtained for safe use in the oral cavity. CONCLUSIONS: Incorporating CTMA into composites resulted in similar chemical and mechanical properties compared to Bis-GMA-based material while reducing viscosity, water sorption and solubility. CLINICAL RELEVANCE: CTMA could be used as a trimethacrylate monomer replacing Bis-GMA in resin composites, thereby minimizing BPA exposure.


Asunto(s)
Bisfenol A Glicidil Metacrilato , Resinas Compuestas , Resistencia Flexional , Ensayo de Materiales , Fenoles , Ácidos Polimetacrílicos , Solubilidad , Resinas Compuestas/química , Bisfenol A Glicidil Metacrilato/química , Fenoles/química , Viscosidad , Ácidos Polimetacrílicos/química , Módulo de Elasticidad , Metacrilatos/química , Termogravimetría , Polietilenglicoles/química , Anacardium/química
3.
Foods ; 13(17)2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39272549

RESUMEN

Despite the high global production of beetroot (Beta vulgaris L.), its peel is often discarded. Transforming beetroot into flour can reduce waste, improve food security, and decrease environmental pollution. However, large-scale feasibility depends on understanding drying kinetics and optimal storage conditions. This study aimed to investigate the effects of different temperatures in the convective drying of whole beetroot and evaluate the influence of laminated flexible and plastic packaging on flour stability over two months. Drying kinetics were analyzed using five models, with the Page and Logarithm models showing the best fit (R2 > 0.99). Def values (1.27 × 10-9 to 2.04 × 10-9 m2 s-1) increased with rising temperatures while drying time was reduced (from 820 to 400 min), indicating efficient diffusion. The activation energy was 29.34 KJ mol-1, comparable to other plant matrices. Drying reduced moisture and increased ash concentration in the flour. The flour showed a good water adsorption capacity and low cohesiveness, making it marketable. Laminated packaging was more effective in controlling physicochemical parameters, reducing hygroscopicity, and maintaining quality over 60 days. In summary, the Page model can predict beetroot drying kinetics effectively, and laminated packaging can control flour stability.

4.
J Mech Behav Biomed Mater ; 157: 106652, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38970944

RESUMEN

The present study examined different concentrations of the butylated hydroxytoluene (BHT) inhibitor on the kinetics of conversion, polymerization shrinkage stress, and other correlated physicochemical properties of experimental resin composites (ERC). A model composite was formulated with 75 wt% filler containing 0.5 wt% camphorquinone and 1 wt% amine with BHT concentrations of 0.01 wt% (BHT-0.01); 0.1 wt% (BHT-0.1); 0.25 wt% (BHT-0.25); 0.5 wt% (BHT-0.5); 1 wt% (BHT-1), and control (no BHT). They were tested on polymerization shrinkage stress (PSS; n = 5), degree of conversion (DC; n = 3), maximum polymerization rate (RpMAX; n = 5), water sorption (Wsp; n = 0), and solubility (Wsl; n = 10), flexural strength (FS; n = 10), flexural modulus (FM; n = 10), Knoop microhardness (KH; n = 10), and microhardness reduction (HR; n = 10). Data concerning these tests were submitted to one-way ANOVA and Tukey's test (α = 0.05; ß = 0.2). BHT-0.25, BHT-0.5, and BHT-1 showed a gradually significant decrease in PSS (p = 0.037); however, BHT-1 demonstrated a decrease in the physicochemical properties tested. Thus, within the limitations of this study, it was possible to conclude that BHT concentrations between 0.25 and 0.5 wt% are optimal for reducing shrinkage stress without affecting other physicochemical properties of ERCs.


Asunto(s)
Hidroxitolueno Butilado , Resinas Compuestas , Ensayo de Materiales , Polimerizacion , Estrés Mecánico , Hidroxitolueno Butilado/química , Resinas Compuestas/química , Fenómenos Químicos , Solubilidad , Agua/química , Dureza
5.
Food Chem ; 458: 140196, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38943953

RESUMEN

The research aimed to assess the effects of incorporating germinated Lupinus angustifolius flour into corn extrudates for different periods (3, 5, and 7 days), focusing on starch digestibility, morphological structure, thermal, and pasting properties. Extrudate with germinated lupinus flour for 7 days (EG7) significantly increased the content of slowly digestible starch up to 10.56% (p < 0.05). Crystallinity increased up to 20% in extrudates with germinated flour compared to extrudates with ungerminated flour (EUG), observing changes at the molecular level by FTIR that impact the thermal and pasting properties. X-ray diffraction revealed angles of 2θ = 11.31, 16.60, 19.91, and 33.04 as a result of the germination and extrusion processes. Microstructural analysis indicated starch-protein interactions influencing changes in calorimetry, viscosity, X-ray diffraction, and digestibility. PCA allowed establishing that the addition of germinated flours significantly affected the properties and microstructural characteristics of extruded products, potentially affecting digestibility and nutritional quality.


Asunto(s)
Digestión , Germinación , Lupinus , Almidón , Difracción de Rayos X , Zea mays , Zea mays/química , Zea mays/crecimiento & desarrollo , Zea mays/metabolismo , Lupinus/química , Lupinus/metabolismo , Lupinus/crecimiento & desarrollo , Almidón/química , Almidón/metabolismo , Harina/análisis , Viscosidad , Semillas/química , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Manipulación de Alimentos
6.
Heliyon ; 10(11): e32225, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38868042

RESUMEN

The impact of high-intensity ultrasound (HIU, 20 kHz) on the physicochemical and functional characteristics of gourd seed protein isolate (GoSPI) was studied. GoSPI was prepared from oil-free gourd seed flour through alkaline extraction (pH 11) and subsequent isoelectric precipitation (pH 4). The crude protein concentration of GoSPI ranged from 91.56 ± 0.17 % to 95.43 ± 0.18 %. Aqueous suspensions of GoSPI (1:3.5 w/v) were ultrasonicated at powers of 200, 400, and 600 W for 15 and 30 min. Glutelins (76.18 ± 0.15 %) were the major protein fraction in GoSPI. HIU decreased the moisture, ash, ether extract, and nitrogen-free extract contents and the hue angle, available water and a* and b* color parameters of the GoSPI in some treatments. The L* color parameter increased (7.70 %) after ultrasonication. HIU reduced the bulk density (52.63 %) and particle diameter (39.45 %), as confirmed by scanning electron microscopy, indicating that ultrasonication dissociated macromolecular aggregates in GoSPI. These structural changes enhanced the oil retention capacity and foam stability by up to 62.60 and 6.84 %, respectively, while the increases in the solvability, water retention capacity, and emulsifying activity index of GoSPI were 90.10, 19.80, and 43.34 %, respectively. The gelation, foaming capacity, and stability index of the emulsion showed no improvement due to HIU. HIU altered the secondary structure of GoSPI by decreasing the content of α-helices (49.66 %) and increasing the content of ß-sheets (52.00 %) and ß-turns (65.00 %). The electrophoretic profile of the GoSPI was not changed by HIU. The ultrasonicated GoSPI had greater functional attributes than those of the control GoSPI and could therefore be used as a functional food component.

7.
J Endod ; 50(9): 1333-1339, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38901643

RESUMEN

INTRODUCTION: The purpose of this study was to evaluate whether the mixing method of AH Plus Jet sealer affects its physicochemical and mechanical properties. METHODS: The properties of AH Plus Jet sealer were analyzed when mixed using either the Auto Mix Tip or manual mixing. The evaluated properties included radiopacity (n = 5), initial and final setting times (n = 5), flow (n = 5), and solubility (n = 3), following specifications outlined in ISO 6876/2012 and ADA Nº 57/2000. pH levels were measured at intervals of 3, 24, 72, and 168 hours (n = 10). The push-out bond strength test was conducted using a universal testing machine and using bovine teeth (n = 30). Failure modes were analyzed with stereomicroscopy. Porosity was evaluated under micro-CT (n = 5), and scanning electron microscopy was also performed (n = 5). One-way analysis of variance and Tukey, unpaired t-tests, or Mann-Whitney tests were used with a significance level of 5%. RESULTS: The Auto Mix exhibited a radiopacity value of 12.11 mmAl, whereas manual mixing resulted in 12.55 mmAl (P > .05). For initial and final setting times, Auto Mix showed 901 minutes and 1779 minutes, respectively, while manual mixing recorded values of 631 minutes and 1504 minutes (P < .05). In terms of flow, Auto Mix demonstrated higher values (25.26 mm) than manual mixing (21.71 mm) (P < .05). No statistical differences were observed between the two methods for solubility and pH (P > .05). Manual mixing presented a higher bond strength value (14.52 MPa) than Auto Mix (9.81 MPa) (P < .05). The mixed failure mode was the most frequent outcome for both methods. The highest porosity was observed for Auto Mix (P < .05). Scanning electron microscopy analysis revealed that manual mixing resulted in a smoother surface with fewer pores and smaller, more evenly distributed agglomerates compared to automatic mixing. CONCLUSION: The mixing method employed for AH Plus Jet sealer influences some physicochemical and mechanical properties of the material.


Asunto(s)
Resinas Epoxi , Ensayo de Materiales , Materiales de Obturación del Conducto Radicular , Materiales de Obturación del Conducto Radicular/química , Bovinos , Animales , Resinas Epoxi/química , Microscopía Electrónica de Rastreo , Solubilidad , Concentración de Iones de Hidrógeno
8.
Foods ; 13(10)2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38790865

RESUMEN

In this study, the oils of açaí, passion fruit, pequi, and guava were submitted to physicochemical analysis to investigate their potential application in the food industry. Gas chromatography associated with mass spectroscopy showed that oleic and linoleic acids are mainly responsible for the nutritional quality of açaí, passion fruit, pequi, and guava oils, which exhibited 46.71%, 38.11%, 43.78%, and 35.69% of the former fatty acid, and 18.93%, 47.64%, 20.90%, and 44.72% of the latter, respectively. The atherogenicity index of the oils varied from 0.11 to 0.65, while the thrombogenicity index was 0.93 for açaí, 0.35 for guava, and 0.3 for passion fruit oils, but 1.39 for pequi oil, suggesting that the use of the first three oils may lead to a low incidence of coronary heart disease. Thermogravimetry showed that all tested oils were thermally stable above 180 °C; therefore, they can be considered resistant to cooking and frying temperatures. In general, the results of this study highlight possible applications of these oils in the food industry, either in natura or in typical food production processes.

9.
Food Chem ; 451: 139395, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38703736

RESUMEN

Amaranth is a pseudocereal that contains between 50 and 60% starch, gluten-free protein, and essential amino acids. This study investigates the physicochemical changes in Amaranthus spp. grains, flour, isolated starch and nanocrystals during germination and malting. The moisture content increased from 8.9% to 41% over 2 h of soaking. The percentage of germination increased rapidly, reaching 96% after 60 h, a remarkable advantage over other cereals. The nutrient composition varied, including protein synthesis and lipid degradation. Lipid concentration decreased during malting, except for soaking, which increased by 62%. Scanning electron microscopy shows that germination does not cause morphological changes on the outer surface of the grains, while transmission electron microscopy indicates the presence of isolated nanocrystals with orthorhombic crystal structure confirmed by X-ray diffraction. The viscosity profile shows a decrease in peak viscosity. Therefore, amaranth is a potential pseudocereal that can be used as an additive in the production of fermented beverages.


Asunto(s)
Amaranthus , Harina , Germinación , Nanopartículas , Almidón , Amaranthus/química , Amaranthus/crecimiento & desarrollo , Amaranthus/metabolismo , Harina/análisis , Almidón/química , Almidón/metabolismo , Nanopartículas/química , Viscosidad , Semillas/química , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Manipulación de Alimentos
10.
Foods ; 13(7)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38611331

RESUMEN

In this study, the effect of different heating temperatures (80, 90, 100, and 121 °C) on the physicochemical and volatile flavor properties of fried mantles (Argentinian shortfin) was investigated. The squid mantles were soaked in a maltose syrup solution (20% w/v) for 10 s and fried in soybean oil for 10 s (160 °C), vacuum-packed, and processed at different temperatures for 10 min. Then, the squid mantles were subjected to colorimetric analysis, sensory evaluation, free amino acid analysis, and texture profile analysis. In addition, the volatile organic compounds (VOCs) in the squid mantles were analyzed. The results revealed that lower treating temperatures (80 and 90 °C) improved the chromatic and textural properties, along with organoleptic perception. Additionally, the content of amino acid in the squid mantles treated at 121 °C was significantly lower than that of the samples treated at other temperatures (p < 0.05). Headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) was used to detect 41 VOCs, including their monomers and dimers. Among these detected VOCs, the contents of alcohols, ketones, and pyrazines were positively correlated with temperature. However, the content of aldehydes in the squid mantles gradually decreased as the heating temperature increased (p < 0.05). The combined HS-GC-IMS and E-nose results revealed that the lower temperatures (80 and 90 °C) were more suitable for flavor development and practical processing. This study provides valuable information for properly controlling the heating process of squid products, as well as flavor and practical applications for the aquatic industry.

11.
Plants (Basel) ; 13(7)2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38611564

RESUMEN

The hard-shelled seed industry plays an important role in the global agricultural economy. In fact, only considering hazelnut and walnut, the global nut supply is over 5.6 tons. As a result considerable amounts are produced year by year, burnt or discarded as waste, bypassing a potential source of valuable compounds or features. This review deals with the recent scientific literature on their chemical composition as well as functional applications as an approach to sustain the utilization of the main byproduct derived from industry. Indeed, nutshells have received great interest due to their lignin, antioxidant, physical and mechanical features. It was found that these properties vary among cultivars and localities of plantation, influencing physical and structural features. The inconsistencies regarding the above-mentioned properties of nutshells lead to exploring the status of hazelnut and walnut shell applications in sustainable bio-economy chains. In fact, in terms of potential applications, the state of the art links their use to the construction industry and the manufacture of materials, such as resin or plastic composites, particleboards or construction panels, or vital infrastructure and as a filler in cement pavements. However, their current use continues bypassing their great antioxidant potential and their interesting chemical and mechanical features.

12.
Polymers (Basel) ; 16(8)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38675037

RESUMEN

Corneal diseases represent a significant global health challenge, often resulting in blindness, for which penetrating keratoplasty is the clinical gold standard. However, in cases involving compromised ocular surfaces or graft failure, osteo-odonto keratoprosthesis (OOKP) emerges as a vital yet costly and complex alternative. Thus, there is an urgent need to introduce soft biomaterials that mimic the corneal tissue, considering its translation's physicochemical, biological, and economic costs. This study introduces a cross-linked mixture of economically viable biomaterials, including gelatin, chitosan, and poly-D-lysine, that mimic corneal properties. The physicochemical evaluation of certain mixtures, specifically gelatin, chitosan, and poly-D-lysine cross-linked with 0.10% glutaraldehyde, demonstrates that properties such as swelling, optical transmittance, and thermal degradation are comparable to those of native corneas. Additionally, constructs fabricated with poly-D-lysine exhibit good cytocompatibility with fibroblasts at 72 h. These findings suggest that low-cost biopolymers, particularly those incorporating poly-D-lysine, mimic specific corneal characteristics and have the potential to foster fibroblast survival. While further studies are required to reach a final corneal-mimicking solution, this study contributes to positioning low-cost reagents as possible alternatives to develop biomaterials with physicochemical properties like those of the human cornea.

13.
Polymers (Basel) ; 16(6)2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38543386

RESUMEN

Developing a powder-form natural antioxidant additive involves utilizing polyphenols extracted from agro-industrial wastes (walnut green husk). This research explores chickpea proteins (CPP) as an emergent encapsulating agent to enhance the stability and shelf life of the antioxidant additive. This study aims to develop a natural antioxidant powder additive based on polyphenols obtained from walnut green husks encapsulated by chickpea protein (5%, 7.5%, and 10% w/v) to evaluate their effect under storage at relative humidities (33 and 75% RH). The physicochemical and structural properties analysis indicated that better results were obtained by increasing the protein concentration. This demonstrates the protective effect of CPP on the phenolic compounds and that it is potentially non-toxic. The results suggest that the optimal conditions for storing the antioxidant powder, focusing on antioxidant activity and powder color, involve low relative humidities (33%) and high protein concentration (10%). This research will contribute to demonstrating chickpea protein as an emerging encapsulating agent and the importance of the cytotoxic analysis of extracts obtained from agroindustrial wastes.

14.
Polymers (Basel) ; 16(6)2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38543443

RESUMEN

Tara gum, a natural biopolymer extracted from Caesalpinia spinosa seeds, was investigated in this study. Wall materials were produced using spray drying, forced convection, and vacuum oven drying. In addition, a commercial sample obtained through mechanical methods and direct milling was used as a reference. The gums exhibited low moisture content (8.63% to 12.55%), water activity (0.37 to 0.41), bulk density (0.43 to 0.76 g/mL), and hygroscopicity (10.51% to 11.42%). This allows adequate physical and microbiological stability during storage. Polydisperse particles were obtained, ranging in size from 3.46 µm to 139.60 µm. Fourier transform infrared spectroscopy characterisation confirmed the polysaccharide nature of tara gum, primarily composed of galactomannans. Among the drying methods, spray drying produced the gum with the best physicochemical characteristics, including higher lightness, moderate stability, smaller particle size, and high glass transition temperature (141.69 °C). Regarding rheological properties, it demonstrated a non-Newtonian pseudoplastic behaviour that the power law could accurately describe. The apparent viscosity of the aqueous dispersions of the gum decreased with increasing temperature. In summary, the results establish the potential of tara gum as a wall material applicable in the food and pharmaceutical industries.

15.
Odontology ; 112(3): 773-781, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38305943

RESUMEN

This study analyzed and compared the physicochemical and mechanical properties of preheated resin composite with light-cured resin cement for luting indirect restorations. 210 specimens of resin cement/resin composite were prepared according to preheating treatment heated (Htd) or not (NHtd). Light-cured resin cement (Variolink Veneer, Ivoclar), and resin composite (Microhybrid-Z100, 3 M; Nanohybrid-Empress direct, Ivoclar; and Bulk fill-Filtek One, 3 M) were used (n = 10). Resin cement specimens were not preheated. The response variables were (n = 10): film thickness, microhardness, liquid sorption and solubility. Data were analyzed by 2-way ANOVA and Tukey HSD post-test (α = 0.05). Bulk fill NHtd resin had the highest film thickness values (p < 0.001). Microhybrid and nanohybrid Htd resins had the smallest thicknesses and did not differ from the cement (p > 0.05). The highest microhardness values were found for Bulk fill NHtd and Bulk fill Htd resins. The nanohybrid and microhybrid Htd resins showed the lowest microhardness values, with no difference in cement (p > 0.05). For liquid sorption, there was no significant difference between the groups (p = 0.1941). The microhybrid Htd resin showed higher solubility values than the other materials (p = 0.0023), but it did not differ statistically from resin cement (p > 0.05). Preheating composite resins reduced the film thickness. After heating, nanohybrid and Bulk fill resins retained stable microhardness, sorption, and solubility values.


Asunto(s)
Cerámica , Resinas Compuestas , Ensayo de Materiales , Solubilidad , Resinas Compuestas/química , Cerámica/química , Cementos de Resina/química , Propiedades de Superficie , Dureza , Calor , Fenómenos Químicos
16.
Sci Rep ; 14(1): 4805, 2024 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-38413681

RESUMEN

A computational study of the peptides Cruzioseptin-4 and Pictuseptin-1, identified in Cruziohyla calcarifer and Boana picturata respectively, has been carried out. The studies on Cruzioseptin-4 show that it is a cationic peptide with a chain of 23 amino acids that possess 52.17% of hydrophobic amino acids and a charge of + 1.2 at pH 7. Similarly, Pictuseptin-1 is a 22 amino acids peptide with a charge of + 3 at pH 7 and 45.45% of hydrophobic amino acids. Furthermore, the predominant secondary structure for both peptides is alpha-helical. The physicochemical properties were predicted using PepCalc and Bio-Synthesis; secondary structures using Jpred4 and PredictProtein; while molecular docking was performed using Autodock Vina. Geometry optimization of the peptides was done using the ONIOM hybrid method with the HF/6-31G basis set implemented in the Gaussian 09 program. Finally, the molecular docking study indicates that the viable mechanism of action for both peptides is through a targeted attack on the cell membrane of pathogens via electrostatic interactions with different membrane components, leading to cell lysis.


Asunto(s)
Péptidos Catiónicos Antimicrobianos , Péptidos Antimicrobianos , Animales , Péptidos Catiónicos Antimicrobianos/química , Simulación del Acoplamiento Molecular , Anuros/metabolismo , Aminoácidos
17.
Braz. dent. j ; Braz. dent. j;35: e24, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS, BBO - Odontología | ID: biblio-1564087

RESUMEN

Abstract This study evaluated the setting time, pH, calcium ion release, solubility, and chemical structure of four calcium silicate sealers after ultrasonic activation (UA). Five sealers were evaluated: Sealer Plus (SP - control); Sealer Plus BC (SPBC), Bio C Sealers (BCS), Endosequence BC Sealer (EBC), and BioRoot RCS (BR). Ten groups were created based on the use or not of ultrasonic activation: SP; SP/UA; SPBC; SPBC/UA; BCS; BCS/UA; EBC; EBC/UA; BR; and BR/UA. Setting time was performed based on ISO 6876:2012 and ASTM C266-07 specifications. Solubility at 24hs, based on ISO 6876:2012. pH and calcium release were evaluated at 1, 24, 72, and 168hs. Raman spectroscopy was used to evaluate structural changes. Quantitative data were analyzed using One-Way ANOVA and Tukey post-hoc test (α=5%). Raman spectroscopy results were qualitatively analyzed. Setting times and solubility of all sealers were not affected by UA (p>0.05). The highest solubility was found for BCS, BCS/UA; and BR, BR/UA (p<0.05). After 24hs, calcium silicate sealers had higher pH than SP and SP/UA (p<0.05). BR and BR/UA had the highest pH at all time points. SP and SP/UA had stable pH at all time points. SP and SP/UA had the lowest calcium release values at all time points (p<0.05). EBC and EBC/UA calcium release significantly differ at 24,72 and 168hs (p<0.05). No chemical changes were observed during Raman spectroscopy. In conclusion, ultrasonic activation affected calcium ion release only for EndoSequence BC Sealer. Ultrasonic activation did not influence the initial and final setting time, solubility, pH, and chemical structure of any investigated sealers.


Resumo Esse estudo avaliou o tempo de presa, pH, liberação de íons cálcio, solubilidade e estrutura química de quatro cimentos à base de silicate de cálcio após a ativação ultrassônica . Cinco cimentos foram avaliados: Sealer Plus (SP - control); Sealer Plus BC (SPBC), Bio C Sealers (BCS), Endosequence BC Sealer (EBC) e BioRoot RCS (BR). Dez grupos foram criados com base no uso ou não de ativação ultrassônica: SP; SP/UA; SPBC; SPBC/UA; BCS; BCS/UA; EBC; EBC/UA; BR; e BR/UA. Tempo de presa foi realizado baseado nas especificações ISO 6876:2012 e ASTM C266-07. Solubilidade em 24hs, baseado na ISO 6876:2012. pH e liberação de cálcio foram avaliados em 1, 24, 72 e 168hs. Espectroscopia Raman foi usada para avaliar alterações estruturais. Os dados quantitativos foram analisados utilizando ANOVA de uma via e teste post-hoc de Tukey (α=5%). Os resultados da espectroscopia Raman foram analisados qualitativamente. Os tempos de presa e a solubilidade de todos os cimentos não foram afetados pelo AU (p>0.05). Maior solubilidade foi encontrada para BCS, BCS/AU; e BR, BR/AU (p<0.05). Após 24hs, os cimentos de silicato de cálcio apresentaram pH mais elevado que SP e SP/AU (p<0.05). BR e BR/AU tiveram o pH mais alto em todos os momentos. SP e SP/AU apresentaram pH estável em todos os momentos. SP e SP/AU tiveram os menores valores de liberação de cálcio em todos os momentos (p<0.05). A liberação de cálcio EBC e EBC/AU diferiram significativamente em 24,72 e 168hs (p<0.05). Nenhuma alteração química foi observada durante a espectroscopia Raman. Em conclusão, a ativação ultrassônica afetou a liberação de íons cálcio apenas para o EndoSequence BC Sealer. A ativação ultrassônica não influenciou o tempo de presa inicial e final, a solubilidade, o pH e a estrutura química de nenhum dos cimentos investigados.

18.
rev. udca actual. divulg. cient ; 26(2): e2132, jul.-dic. 2023. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1576971

RESUMEN

RESUMEN El árbol de totumo Crescentia cujete L. crece en la Costa Atlántica colombiana y sus estudios se han orientado al fruto, tronco y hojas, excepto las semillas consideradas desecho. El objetivo de este trabajo fue determinar la composición química del aceite y torta de las semillas del totumo. Se recolectaron frutos maduros, se sacaron las semillas y se extrajo el aceite, mediante prensado y solventes. A estos aceites se le midieron propiedades fisicoquímicas y se determinó la composición química, por HPLC. A la torta se le realizó análisis proximal. El método de extracción con mayor rendimiento fue el del solvente. El aceite demostró estabilidad y alta resistencia a la oxidación; su composición química presentó el 75 % de ácidos grasos insaturados y el 24 % saturados. El análisis proximal reveló alto valor nutricional. El aceite de las semillas y su torta pueden ser aprovechables en la industria alimentaria.


ABSTRACT The calabash tree Crescentia cujete L. grows on the Colombian Atlantic Coast, its studies have focused on the fruit, trunk, and leaves, except for the seeds considered waste. The purpose of this work was to determine the chemical composition of the oil and cake of the seeds of calabash tree. Ripe fruits were collected, seeds were removed, and the oil was extracted by pressing and solvent methods. Physicochemical properties were measured for these oils and the chemical composition was determined by HPLC. The cake underwent proximal analysis. The extraction method with the highest yield was the solvent. The oil demonstrated stability and high resistance to oxidation; its chemical composition presented 75 % unsaturated fatty acids and 24 % saturated. The proximal analysis revealed high nutritional value. The oil from the seeds and their cake can be used in the food industry.

19.
Foods ; 12(19)2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37835239

RESUMEN

In this research, muffin-type bakery products were developed based on wheat flour (WF) and mesquite flour (MF) in the following proportions: WFMF 90:10, WFMF 75:25, and WFMF 50:50. The products were characterized based on various properties in which it was possible to observe that the water activity (aw) did not show a significant change with the increase in the concentration of MF. In addition, the increase in the concentration of MF modified the sensory properties (color, odor, flavor, texture, and acceptance), further decreasing the luminosity and increasing the values of the a* and b* coordinates. Moreover, in the texture profile analysis, it was found that the increase in the MF concentration increased hardness, fracturability, and gumminess and decreased adhesiveness and cohesiveness. All the previously mentioned changes were more evident in the WFMF50:50 and, to a lesser degree, in WFMF75:25. In general, in most evaluations realized, the WFMF90:10 treatment was the most similar to the control (without MF). However, WFMMF75:25 provided a higher protein and fiber content and a lower fat content. Finally, it is possible to use the flour obtained from the mesquite fruit to make bakery products since it is an important source of food due to the wide distribution of mesquite in the country.

20.
Front Chem ; 11: 1267634, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37795387

RESUMEN

Introduction: The green revolution model that is followed in the Brazilian Cerrado is dependent on mechanization, chemical fertilization for soil dressing and correction, and the use of herbicides. Paraquat is a methyl viologen herbicide marketed as bipyridylium dichloride salts and used (in low doses) to combat weeds in their post-emergence stage. It is a non-selective pesticide that causes the peroxidation of the lipids that make up the cell membrane, and when it comes into contact with foliage, it results in the death of the plant. Methods: The effect of water molecules co-crystallized in Paraquat salt structures was analyzed in anhydrous, dihydrate, and trihydrate forms to understand those physicochemical properties in its redox activity. The frontier molecular orbitals were also carried out using DFT to obtain the chemical reactivity of the bipyridylium cation. Finally, the supramolecular arrangements were evaluated to analyze the physicochemical stability and acquire insights on superoxide anions. Results and discussion: The electronic structure indicated that the BP cation presents an acidic character due to its low ELUMO value, while the salt has a more basic character due to its high EHOMO value. For this reason, the BP ion is more susceptible to reduction during the weeds' photosynthesis process. During the process of plant photosynthesis, PQ is reduced to form a stable radical cation. In the supramolecular arrangement, the presence of water molecules increases the number of strong H-bonds, while the weak/moderate H-bonds are stabilized. PQ's toxic effects are observed in wildlife, domesticated animals, human populations, and ecosystems. The influence of PQ on the terrestrial environment is limited because of the soil adsorption capacity associated with good agricultural practices. The current use of good agricultural practices in the Cerrado seems not to prevent the environmental impacts of herbicides like PQ because it aims for the expansion and profitability of large-scale farming based on input-intensive practices instead of sustainable agriculture processes.

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