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1.
Int J Biol Macromol ; 268(Pt 1): 131601, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38626833

RESUMO

This study investigates the impact of water and salinity stress on Aloe vera, focusing on the role of Aloe vera polysaccharides in mitigating these stresses. Pectins and acemannan were the most affected polymers. Low soil moisture and high salinity (NaCl 80 mM) increased pectic substances, altering rhamnogalacturonan type I in Aloe vera gel. Aloe vera pectins maintained a consistent 60 % methyl-esterification regardless of conditions. Interestingly, acemannan content rose with salinity, particularly under low moisture, accompanied by 90 to 150 % acetylation increase. These changes improved the functionality of Aloe vera polysaccharides: pectins increased cell wall reinforcement and interactions, while highly acetylated acemannan retained water for sustained plant functions. This study highlights the crucial role of Aloe vera polysaccharides in enhancing plant resilience to water and salinity stress, leading to improved functional properties.

2.
Foods ; 11(23)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36496559

RESUMO

The use of artificial neural networks (ANNs) is proposed to optimize the formulation of stable oil-in-water emulsions (oil 6% w/w) with a flour made from orange by-products (OBF), rich in pectins (21 g/100 g fresh matter), in different concentrations (0.95, 2.38, and 3.40% w/w), combined with or without soy proteins (0.3 and 0.6% w/w). Emulsions containing OBF were stable against coalescence and flocculation (with 2.4 and 3.4% OBF) and creaming (3.4% OBF) for 24 h; the droplets' diameter decreased up to 44% and the viscosity increased up to 37% with higher concentrations of OBF. With the protein addition, the droplets' diameter decreased by up to 70%, and flocculation increased. Compared with emulsions produced with purified citrus pectins (0.2 and 0.5% w/w), OBF emulsions exhibited up to 32% lower viscosities, 129% larger droplets, and 45% smaller Z potential values. Optimization solved with ANNs minimizing the droplet size and the emulsion instability resulted in OBF and protein concentrations of 3.16 and 0.14%, respectively. The experimental characteristics of the optimum emulsion closely matched those predicted by ANNs demonstrating the usefulness of the proposed method.

3.
Foods ; 11(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36076833

RESUMO

The bioactive compounds, antioxidant capacity and microbiological quality of melon juice processed by high-intensity ultrasound (HIUS) were studied. Melon juice was processed at two ultrasound intensities (27 and 52 W/cm2) for two different processing times (10 and 30 min) using two duty cycles (30 and 75%). Unprocessed juice was taken as a control. Total carotenoids and total phenolic compounds (TPC) were the bioactive compounds analyzed while the antioxidant capacity was determined by DPPH, ABTS and FRAP assays. The microbiological quality was tested by counting the aerobic and coliforms count as well as molds and yeasts. Total carotenoids increased by up to 42% while TPC decreased by 33% as a consequence of HIUS processing regarding control juice (carotenoids: 23 µg/g, TPC: 1.1 mg GAE/g), gallic acid and syringic acid being the only phenolic compounds identified. The antioxidant capacity of melon juice was enhanced by HIUS, achieving values of 45% and 20% of DPPH and ABTS inhibition, respectively, while >120 mg TE/100 g was determined by FRAP assay. Further, the microbial load of melon juice was significantly reduced by HIUS processing, coliforms and molds being the most sensitive. Thus, the HIUS could be an excellent alternative supportive the deep-processing of melon products.

4.
Int J Biol Macromol ; 221: 954-964, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36108747

RESUMO

This work aimed to characterize the physicochemical, structural, morphological, and thermal properties of a non-conventional starch obtained from cubio (Tropaeolum tuberosum), as well as to evaluate the potential use of this native Andean tuber in the preparation of biodegradable packaging. The cubio starch (CUS) showed an intermediated apparent amylose content (31.2 %) accompanied by a high CIE whiteness index (90.8). About the morphology and particle size, the CUS exhibited irregular oval and round shapes and a smooth surface with a mean particle diameter of 14.04 ± 0.1 µm. Although it showed good stability regarding pasting properties, the final viscosity was low. Native CUS exhibits a typical B-type diffraction structure, with a relative crystallinity of 16 %. The resistant starch (RS) fraction of the CUS was 94 %, indicating a low susceptibility to enzymatic hydrolysis. The thermal analysis demonstrated that the CUS showed good thermal stability. Additionally, the films prepared using CUS as raw material showed continuous surfaces without porosities, good thermal stability, and high transparency. The results of this work demonstrate the industrial potential of the CUS as it presents characteristics comparable to commercial potato starch.


Assuntos
Solanum tuberosum , Tropaeolum , Amilose/química , Solanum tuberosum/química , Amido/química , Viscosidade , Difração de Raios X
5.
Ultrason Sonochem ; 88: 106087, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35785623

RESUMO

This research investigated the effects of ultrasound application (192 ± 6 W/L) on the microstructure of vegetables/fruits with different porosities, cell sizes and patterns (eggplants, beetroots, and apples), submitted to an immersion treatment in different liquids: distilled water, citric acid (1% w/v), and the vegetable/fruit juice, at 25 °C during 5 min. The ultrasound application did not significantly (p > 0.05) affect the size of the cells of the most porous material (eggplant) compared to the samples immersed without ultrasound assistance. The apple samples (with a middle-high porosity and the largest cells) were the most affected by ultrasound application. The median cell areas of samples treated with ultrasound in water and apple juice were 26 and 20% larger than those of samples treated without ultrasound, mainly because of cell wall disruption which caused the cells to merge into bigger clusters, but no effect was observed with the citric acid. Ultrasound application significantly (p < 0.05) increased the median cell area of the less porous raw matter (beetroot) only when the treatment was carried out in the vegetable juice (cells were 26% larger after treatment assisted with ultrasound than without it). Thus, the effects of ultrasound differ in materials with initially different characteristics.


Assuntos
Malus , Verduras , Ácido Cítrico/análise , Ácido Cítrico/farmacologia , Frutas/química , Malus/química , Porosidade , Água/análise
6.
Foods ; 10(5)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922734

RESUMO

Valorization of an artichoke by-product, rich in bioactive compounds, by ultrasound-assisted extraction, is proposed. The extraction yield curves of total phenolic content (TPC) and chlorogenic acid content (CAC) in 20% ethanol (v/v) with agitation (100 rpm) and ultrasound (200 and 335 W/L) were determined at 25, 40, and 60 °C. A mathematical model considering simultaneous diffusion and convection is proposed to simulate the extraction curves and to quantify both temperature and ultrasound power density effects in terms of the model parameters variation. The effective diffusion coefficient exhibited temperature dependence (72% increase for TPC from 25 °C to 60 °C), whereas the external mass transfer coefficient and the equilibrium extraction yield depended on both temperature (72% and 90% increases for TPC from 25 to 60 °C) and ultrasound power density (26 and 51% increases for TPC from 0 (agitation) to 335 W/L). The model allowed the accurate curves simulation, the average mean relative error being 5.3 ± 2.6%. Thus, the need of considering two resistances in series to satisfactorily simulate the extraction yield curves could be related to the diffusion of the bioactive compound from inside the vegetable cells toward the intercellular volume and from there, to the liquid phase.

7.
Foods ; 10(2)2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33669757

RESUMO

The reuse of food industry by-products constitutes one of the essential pillars of the change from a linear to a circular economic model. Drying is one of the most affordable techniques with which to stabilize by-products, making their subsequent processing possible. However, it can affect material properties. The objective of this study was to assess the effect of the drying temperature on the drying kinetics and final quality of the main artichoke processing by-products, bracts and stems, which have never been studied as independent materials. For this purpose, air drying experiments at different temperatures (40, 60, 80, 100 and 120 °C) were carried out. The alcohol insoluble residue (AIR) and the total phenolic content (TPC), antioxidant capacity (AC) and vitamin C (VC) of the fresh and dried samples were determined. The bracts dried faster than the stems, increasing drying rate with temperature. The two by-products presented relatively large amounts of AIR, the content being higher in bracts, but better functional properties in stems. The TPC, AC and VC values of the dried samples decreased in relation to the fresh samples, with the temperatures of 40 °C (bracts) and 120 °C (stems) being the most adequate for the purposes of preserving these characteristics.

8.
Food Chem ; 343: 128429, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33127232

RESUMO

The by-product generated after ergosterol extraction from mushrooms (A. bisporus) is rich in polysaccharides (ß-glucans) and proteins. The usefulness of this mushroom's by-product (MC) in oil microencapsulation by spray drying was evaluated partially replacing maltodextrin (13.5% w/w dry matter) and totally substituting Tween®20 with MC. Ergosterol was investigated as antioxidant. Non-Newtonian stable emulsions with mono-modal droplet size distributions were obtained with MC. Oil encapsulation efficiency was high (≥89%) and oil within microcapsules containing MC exhibited higher (p < 0.05) oxidative stability during spray drying. Powders containing MC exhibited larger particles (d5027% larger), 12% lower solubility in water and perceptible color changes. During storage (35 °C 50% RH), conjugated dienes increased more slowly in microcapsules containing MC. Reductions up to 28% in linoleic acid were observed after 150 days. Ergosterol was 95% degraded after 150 days in powders with MC and totally degraded after 2 days in powders without MC.


Assuntos
Agaricales , Cápsulas/química , Emulsões/química , Óleo de Girassol/química , Ergosterol/química , Armazenamento de Alimentos , Oxirredução , Polissacarídeos/química , Pós , Secagem por Atomização , Resíduos , Água
9.
Food Chem ; 332: 127390, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32603922

RESUMO

Revalorization of mushroom by-product (stalks of A. bisporus) by extracting its components is proposed. The extraction kinetics at 25 °C of ergosterol, phenolic compounds and antioxidant activity by mechanical agitation (at 130 rpm) and ultrasound assistance (at 182 and 321 W/L) in 70 and 96% v/v ethanol/water solutions during 30 min were evaluated and satisfactorily modelled, using the Weibull model (mean relative error ≤ 7.8%). The effect of the ethanol concentration was high in the ergosterol extraction yield (2 times higher yields in 96% than in 70%) but slight in those of phenolic compounds and antioxidant activity. Ultrasound assistance promoted considerable yield increases (up to 2 times higher in ergosterol, 46% in phenolic compounds and 25% in antioxidant activity) depending on the ethanol concentration and ultrasound power density. The residues after extraction were characterized and constituted a potential source of high value polysaccharides as ß-glucans (average 12.2 ± 1.7g/100 g dm).


Assuntos
Agaricales/química , Antioxidantes/química , Ergosterol/química , Extração em Fase Sólida/métodos , beta-Glucanas/química , Agaricales/metabolismo , Antioxidantes/isolamento & purificação , Ergosterol/isolamento & purificação , Etanol/química , Modelos Teóricos , Fenóis/química , Sonicação
10.
J Sci Food Agric ; 99(15): 6893-6902, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31386201

RESUMO

BACKGROUND: The ultrasound-assisted extraction of pectic polysaccharides from orange by-products was investigated. Kinetics of mechanical agitation (0.2 × g) and acoustic (US1: 542 W L-1 and US2: 794 W L-1 ) extractions, were obtained and modelled at different pH values (1.5 and 2.0). All extractions were carried out at 25 °C, using citric acid as the extraction solvent. RESULTS: Higher pectic polysaccharides extraction yields were obtained with ultrasonic assistance, in comparison with the results obtained using mechanical agitation. Moreover, yield increases were significantly higher using the more acidic pH. Thus, at pH 1.5, pectin yield increased from ∼19%, obtained with agitation, to ∼47%, applying ultrasound; whereas, at pH 2.0, this increase was from ∼10%, with agitation, to ∼18%, applying ultrasound. A considerable decrease of the galacturonic acid proportion was observed on the extracts when ultrasound were applied for 60 min under pH 2.0. High methoxyl pectins were extracted at pH 1.5 whereas at pH 2.0, pectins exhibited a low methylation degree. Curves of acoustic and mechanical agitation extractions were properly represented by a second-order rate model (average mean relative error ≤ 7.4%). The extraction rate constant, initial extraction rate and maximum yield were determined for all experimental conditions. CONCLUSION: Overall, the results clearly indicated that the effect of ultrasound was highly dependent on the pH. Therefore, adequate acidic conditions must be applied in order to improve the efficiency of ultrasound on the pectin extraction process. © 2019 Society of Chemical Industry.


Assuntos
Fracionamento Químico/métodos , Citrus/química , Pectinas/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Resíduos/análise , Fracionamento Químico/instrumentação , Citrus/efeitos da radiação , Frutas/química , Frutas/efeitos da radiação , Concentração de Íons de Hidrogênio , Cinética , Pectinas/química , Extratos Vegetais/química , Ondas Ultrassônicas
11.
Int Orthod ; 15(2): 199-207, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28434895

RESUMO

Facial asymmetry requires multidisciplinary management. In some cases, predictable problems due to congenital abnormalities can be corrected by early orthodontic treatment. Orthodontics is nevertheless often part of an orthosurgical treatment plan. The solutions are conventional and familiar: maxillomandibular rotation osteotomy and genioplasty. Many cases can be treated in this way, but there is often persistent residual asymmetry due to loss of volume that is not corrected by these techniques. The use of maxillo-acial endoprostheses designed on the basis of three-dimensional craniofacial analyses can rebalance volumes simply and with due regard to the patient's anatomy. This multistage management will be illustrated here through a complex clinical case.


Assuntos
Assimetria Facial/cirurgia , Implante de Prótese Mandibular , Adulto , Tomografia Computadorizada de Feixe Cônico , Assimetria Facial/diagnóstico , Assimetria Facial/diagnóstico por imagem , Mentoplastia , Humanos , Imageamento Tridimensional , Masculino , Osteotomia Mandibular , Osteotomia Maxilar , Ortodontia Corretiva , Técnica de Expansão Palatina
13.
Photomed Laser Surg ; 31(7): 307-14, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23756100

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effect on dentinal surfaces of diode lasers (810 and 980 nm) at different parameters. MATERIALS AND METHODS: Twenty-four caries-free human impacted wisdom teeth were used. The crowns were sectioned transversely in order to expose the dentin. The smear layer was removed by a 1 min application of ethylenediaminetetraacetic acid (EDTA). Each surface was divided into four quadrants irradiated at a different output power setting for each kind of laser: 0.8, 1, 1.6, and 2 W (energy densities: 2547, 3184, 5092, and 6366 J/cm(2), irradiation speed 1 mm/sec; optical fiber diameter: 200 µm; continuous and noncontact mode). Half of the samples were stained with a graphite paste. All specimens were sent for scanning electron microscopic (SEM) analysis. Pulp temperature increases in additional 20 teeth were measured by a thermocouple. RESULTS: Diode laser irradiations at 0.8 and 1 W led to occlusion or narrowing of dentin tubules without provoking fissures or cracks. The application of graphite paste increased the thermal effects in dentin. Measurements of pulp temperature showed that irradiations at 0.8 and 1 W for a period of 10 sec in continuous mode increased pulp temperature (T ≤2°C). CONCLUSIONS: Diode lasers (810 and 980 nm) used at 0.8 and 1 W for 10 sec in continuous mode were able to seal the dentin tubules. These parameters can be considered harmless for pulp vitality, and may be effective in the treatment of dentinal hypersensitivity.


Assuntos
Dentina/efeitos da radiação , Lasers Semicondutores/uso terapêutico , Adolescente , Adulto , Sensibilidade da Dentina/radioterapia , Humanos , Técnicas In Vitro
14.
Photomed Laser Surg ; 30(11): 655-62, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23075147

RESUMO

OBJECTIVE: The aims of this in vitro study were to evaluate: (1) the influence of 5% NaOCl application on Er:YAG-irradiated dentin; and (2) its effect on the quality of adaptation of the composite restoration margins. BACKGROUND DATA: Previous research has shown that Er:YAG dentin irradiation produces a thermally affected tissue layer that results in lower bond strength than that of nonirradiated dentin. The removal of this thermally-affected layer may enhance the quality of dentin bonding. MATERIALS AND METHODS: Forty-nine caries-free extracted human molars were transversely sectioned in order to totally expose the dentin. Four standardized cavities were created on the dentinal surface of each molar. First, two cavities were irradiated with Er:YAG laser (2.94 nm): 150 mJ, 10 Hz, variable square pulse (VSP) mode (100 µsec), beam diameter=0.9 mm, speed of irradiation=1 mm/sec, 20% air and 20% water. Then, one of irradiated cavities and one of nonirradiated cavities were treated for 30 sec with 5% NaOCl solution. Finally, they went through a standard bonding treatment for composite restoration, etching, bonding, and composite filling. We obtained four groups of cavities: (1) one control group of nonirradiated cavities not pretreated with NaOCl; (2) one group of nonirradiated cavities, pretreated with NaOCl; (3) one group of irradiated cavities, not pretreated with NaOCl; and (4) one group of irradiated cavities, pretreated with NaOCl. All samples were subjected to thermocycling. Every cavity was immersed into a 0.5% solution of methylene blue. The percentage of dye penetration (microleakage) in the composite-dentin interface was evaluated. Six molars were analyzed by scanning electron microscope. RESULTS: Dye infiltration depth was significantly reduced in irradiated cavities treated with 5% NaOCl solution. CONCLUSIONS: The application of a 5% NaOCl solution on Er:YAG irradiated cavities can significantly improve the marginal quality of composite bonding.


Assuntos
Resinas Compostas/uso terapêutico , Adesivos Dentinários/farmacologia , Dentina/efeitos da radiação , Lasers de Estado Sólido , Hipoclorito de Sódio/farmacologia , Adaptação Fisiológica , Colagem Dentária/métodos , Dentina/ultraestrutura , Humanos , Microscopia Eletrônica de Varredura , Dente Molar/efeitos da radiação
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