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1.
Food Sci Biotechnol ; 33(11): 2559-2569, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39144190

RESUMO

In this study, the influence of glycerol and sonicated soybean expeller (SSE) on composite edible films supporting natamycin and nisin was investigated using Response Surface Methodology. Assessments were conducted on mechanical properties, moisture content, water solubility (SW), and color. Optimal results were achieved with 0.46% SSE and 1.4% glycerol, yielding a maximum tensile strength (TS) of 1.0 ± 0.1 MPa and a minimum SW of 19.0 ± 0.3%. SSE had no impact on Tg values (82-89 °C), while antimicrobials reduced Tg (70-73 °C) due to increased water retention. Water vapor permeability was (2.5 ± 0.2) × 10-9  -1 s-1 Pa-1. FTIR analysis revealed strong component interactions. The composite films demonstrated biodegradability in compost after seven days and effective action against Listeria innocua and Saccharomyces cerevisiae. These findings suggest that these materials hold promise as active films for food preservation. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01516-6.

2.
Foods ; 13(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38998507

RESUMO

Modifying starch allows for improvements in its properties to enable improved uses in food matrices, bioplastics, and encapsulating agents. In this research, four varieties of native potato starch were modified by acid treatment, enzymatic treatment, and ethanol precipitation, and their physicochemical, structural, thermal, and techno-functional characteristics were analyzed. According to FT-IR analysis, no influence of the modified starches on the chemical groups was observed, and by scanning electron microscopy (SEM), spherical and oval shapes were observed in the acid and enzymatic treatments, with particle sizes between 27 and 36 µm. In particular, the ethanolic precipitation treatment yielded a different morphology with a particle size between 10.9 and 476.3 nm, resulting in a significant decrease in gelatinization temperature (DSC) and more pronounced crystallites (XRD). On the other hand, the enzymatic treatment showed higher values for z-potential (ζ), and the acid treatment showed lower mass loss (TGA). Acid and ethanolic treatments affected the dough properties compared to native starches. The techno-functional properties showed a decrease in the water absorption index, an increase in the water solubility index, and varied swelling power behaviors. In conclusion, the modification of potato starches through acid, enzymatic, and ethanolic precipitation treatments alters their physicochemical properties, such as swelling capacity, viscosity, and thermal stability. This in turn affects their molecular structure, modifying morphology and the ability to form gels, which expands their applications in the food industry to improve textures, stabilize emulsions, and thicken products. Furthermore, these modifications also open new opportunities for the development of bioplastics by improving the biodegradability and mechanical properties of starch-based plastic materials.

3.
Molecules ; 29(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38611922

RESUMO

Propolis extracts have been widely studied due to their popularity in traditional medicine, presenting incredible biodiversity. This study aimed to analyze propolis extracts' phytochemical, physicochemical, and biological activities from four different biogeographic zones of the Huila region (Colombia). The raw material samples were collected by the scraping method and the ethanolic extracts (EEPs) were obtained by cold maceration with ethanol (96%). The physicochemical and sensory characterization was carried out according to the protocols recommended by the Brazilian Ministry of Agriculture and the main components of the EEPs were identified by LC-HRMS analysis. The determination of total phenols and flavonoids was carried out using colorimetric techniques. The antioxidant activity, cytotoxicity, and cell cycle regulation analyses in L929 and HGnF cells were evaluated using DPPH, Alamar Blue, and 7-amino actinomycin D (7-AAD) assays. The propolis samples presented an average yield of 33.1%, humidity between 1.6 and 2.8%, melting point between 54 and 62 °C, ashes between 1.40 and 2.19%, and waxes of 6.6-17.9%, respectively. The sensory characteristics of all samples were heterogeneous, complying with the quality specifications established by international standards. The polyphenolic and total flavonoid content was representative in the samples from Quebradon (255.9 ± 9.2 mg GAE/g, 543.1 ± 8.4 mg QE/g) and Arcadia (543.1 ± 8.4 mg GAE/g, 32.5 ± 1.18 g QE/g) (p < 0.05) that correlated with high antioxidant activity (Quebradon: 37.2 ± 1.2 µmol/g, Arcadia: 38.19 ± 0.7 µmol/g). In the chemical composition analysis, 19 compounds were characterized as phenolic acids and flavonoids, the most representative being chrysoeriol-O-methyl-ether, ellagic acid, and 3,4-O-dimethylcaffeic acid. Regarding biological activity, Quebradon and Arcadia propolis presented low toxicity with IC50 of 2.83 ± 2.3 mg/mL and 4.28 ± 1.4 mg/mL in HGnF cells, respectively, and an arrest of the cell cycle in the G2/M phase of 71.6% and 50.8% compared to the control (11.9%) (p < 0.05). In general, the results of this study contribute to the identification of valid quality criteria to evaluate Colombian propolis, contributing to its study and chemical and biological characterization as a source of raw material for industrial and pharmaceutical use. In addition, Quebradon and Arcadia propolis can be important sources of bioactive molecules for the development of new drugs.


Assuntos
Ascomicetos , Própole , Antioxidantes/farmacologia , Colômbia , Própole/farmacologia , Ciclo Celular , Etanol , Flavonoides/farmacologia
4.
Nanomaterials (Basel) ; 14(4)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38392745

RESUMO

Because of the physiological and cardiac changes associated with cardiovascular disease, tissue engineering can potentially restore the biological functions of cardiac tissue through the fabrication of scaffolds. In the present study, hybrid nanofiber scaffolds of poly (vinyl alcohol) (PVA) and bioglass type 58S (58SiO2-33CaO-9P2O5, Bg) were fabricated, and their effect on the spontaneous activity of chick embryonic cardiomyocytes in vitro was determined. PVA/Bg nanofibers were produced by electrospinning and stabilized by chemical crosslinking with glutaraldehyde. The electrospun scaffolds were analyzed to determine their chemical structure, morphology, and thermal transitions. The crosslinked scaffolds were more stable to degradation in water. A Bg concentration of 25% in the hybrid scaffolds improved thermal stability and decreased degradation in water after PVA crosslinking. Cardiomyocytes showed increased adhesion and contractility in cells seeded on hybrid scaffolds with higher Bg concentrations. In addition, the effect of Ca2+ ions released from the bioglass on the contraction patterns of cultured cardiomyocytes was investigated. The results suggest that the scaffolds with 25% Bg led to a uniform beating frequency that resulted in synchronous contraction patterns.

5.
Membranes (Basel) ; 13(7)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37505027

RESUMO

Water-soluble polymers provide an alternative to organic solvent requirements in membrane manufacture, aiming at accomplishing the Green Chemistry principles. Poly(vinyl alcohol) (PVA) is a biodegradable and non-toxic polymer renowned for its solubility in water. However, PVA is little explored in membrane processes due to its hydrophilicity, which reduces its stability and performance. Crosslinking procedures through an esterification reaction with carboxylic acids can address this concern. For this, experimental design methodology and statistical analysis were employed to achieve the optimal crosslinking conditions of PVA with citric acid as a crosslinker, aiming at the best permeate production and sodium diclofenac (DCF) removal from water. The membranes were produced following an experimental design and characterized using multiple techniques to understand the effect of crosslinking on the membrane performance. Characterization and filtration results demonstrated that crosslinking regulates the membranes' properties, and the optimized conditions (crosslinking at 110 °C for 110 min) produced a membrane able to remove 44% DCF from water with a permeate production of 2.2 L m-2 h-1 at 3 bar, comparable to commercial loose nanofiltration membranes. This study contributes to a more profound knowledge of green membranes to make water treatment a sustainable practice in the near future.

6.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1551111

RESUMO

En Perú, al 2019, solo el 6,4 % de los distritos disponen sus residuos urbanos en rellenos sanitarios, los cuales, están en situación de colapso, lo que exige buscar alternativas para mejorar la gestión de estos residuos y, frente a ello, el compostaje se perfila como una tecnología simple y económica, empleada para el tratamiento del componente orgánico, para reducir daños a la salud y al ambiente, sin embargo, la falta de criterios técnicos en su aplicación está afectando la calidad del compost final. El objetivo de esta investigación fue evaluar los criterios técnicos de procesamiento y la calidad del compost, a través de residuos sólidos urbanos en los distritos de la provincia Leoncio Prado. La investigación identificó los distritos que aplican el compostaje a sus residuos y evaluó la técnica de procesamiento, indicadores fisicoquímicos y determinó la calidad con base en normas técnicas internacionales. Los resultados muestran que seis de diez distritos aplican el compostaje y los indicadores fisicoquímicos contrastados con los criterios de calidad de la norma técnica chilena (NCH 2880), colombiana 5167 y de la OMS, corresponden a compost de calidad intermedia (Clase B). Los compost evaluados no representan riesgo ambiental y pueden ser utilizados como enmienda en la mejora del suelo y los cultivos con algunas restricciones, por presentar valores elevados de humedad, pH y bajos niveles de P, Ca, Mg y K.


At 2019, in Peru, only 6.4 % of the districts dispose of their urban waste in sanitary landfills, which are in a situation of collapse, therefore is needed looking for alternatives to improve the management of this waste, facing this, composting is emerging as a simple and economical technology used for the treatment of the organic component, thus, reducing damage to health and the environment, however, the lack of technical criteria in its application is affecting the quality of the final compost. The objective of this research was to evaluate the technical criteria for processing and the quality of compost based on municipal solid waste in the districts of Leoncio Prado province. The research identified the districts that apply composting to their waste and evaluated the processing technique, physicochemical indicators and determined the quality based on international technical standards. The results show that six out of ten districts apply composting, and the physicochemical indicators contrasted with the quality criteria of the Chilean technical standard (NCH 2880), Colombian 5167 and WHO, correspond to intermediate quality compost (Class B). The evaluated compost does not represent an environmental risk and can be used as an amendment in soil and crop improvement with some restrictions, since it has high moisture, pH and low levels of P, Ca, Mg and K.

7.
Crit Rev Food Sci Nutr ; 63(19): 4053-4069, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34723729

RESUMO

The Cactaceae family can be easily found in the arid and semiarid regions, with a significant waste of its potentials, being generally used as forage. Considering that much research have shown antioxidant properties and bioactive compounds in cacti species, this review aimed to review and discuss recent advances in physicochemical composition, bioactive compounds, and antioxidant activity of Cereus jamacaru, Melocactus zehntneri, Pilosocereus gounellei, Opuntia ficus-indica and Pilosocereus pachycladus fruits to investigate their food technology potential for new products development. These fruits have important amounts of micro, macronutrients, and bioactive compounds, which allow them a wide variety of uses, fresh or processed, and for industrial purposes for the production and extraction of compounds of interest (dyes, antioxidants, antimicrobials, etc.) as demonstrated in the literature. Furthermore, exploring the diversity of uses of these fruits can provide significant benefits from an economic, technological, social, environment, food, and nutritional security point of view.


Assuntos
Frutas , Opuntia , Humanos , Frutas/química , Antioxidantes/análise , Opuntia/química
8.
J Pharm Sci ; 112(4): 1081-1088, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36528112

RESUMO

Teicoplanin (Teico) is an antimicrobial agent that spontaneously forms micelles in aqueous media. In this work, we characterized the physicochemical properties of nanoparticles formed by the interaction of Teico with Amphotericin B (AmB). Teico-AmB micelles structure spontaneously in aqueous media, with a particle size of 70-100 nm and a zeta potential of -28 mV. Although the characterization of these nanostructures yielded satisfactory results, in vitro cytotoxicity tests showed high toxicity. Based on this, adding cholesterol to the formulation was evaluated to try to reduce the toxicity of the drug. These Teico-AmB-Chol nanostructures have a larger size, close to 160 nm, but a lower polydispersity index. They also showed strongly negative surface charge and were more stable than Teico-AmB, remaining stable for at least 20 days at 4 °C and 25 °C and against centrifugation, dilution, freezing, lyophilization and re-suspension processes with a recovery percentage of AmB greater than 95%, maintaining their initial size and zeta potential. These Teico-AmB-Chol micelles show lower cytotoxic effect and higher biological activity than Teico-AmB, even than Amfostat® and Ambisome® formulations. These two new nanoparticles, with and without Chol, are discussed as potential formulations able to improve the antifungal therapeutic efficiency of AmB.


Assuntos
Anfotericina B , Nanopartículas , Anfotericina B/toxicidade , Anfotericina B/química , Micelas , Teicoplanina , Antifúngicos/toxicidade , Antifúngicos/química , Nanopartículas/química
9.
J Hazard Mater ; 439: 129593, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-35843083

RESUMO

Micro and nanoplastics (MNPLs) are emergent environmental pollutants requiring urgent information on their potential risks to human health. One of the problems associated with the evaluation of their undesirable effects is the lack of representative samples, matching those resulting from the environmental degradation of plastic wastes. To such end, we propose an easy method to obtain polyethylene terephthalate nanoplastics from water plastic bottles (PET-NPLs) but, in principle, applicable to any other plastic goods sources. An extensive characterization indicates that the proposed process produces uniform samples of PET-NPLs of around 100 nm, as determined by using AF4 and multi-angle and dynamic light scattering methodologies. An important point to be highlighted is that to avoid the metal contamination resulting from methods using metal blades/burrs for milling, trituration, or sanding, we propose to use diamond burrs to produce metal-free samples. To visualize the toxicological profile of the produced PET-NPLs we have evaluated their ability to be internalized by cells, their cytotoxicity, their ability to induce oxidative stress, and induce DNA damage. In this preliminary approach, we have detected their cellular uptake, but without the induction of significant biological effects. Thus, no relevant increases in toxicity, reactive oxygen species (ROS) induction, or DNA damage -as detected with the comet assay- have been observed. The use of representative samples, as produced in this study, will generate relevant data in the discussion about the potential health risks associated with MNPLs exposures.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Humanos , Microplásticos/toxicidade , Plásticos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
10.
rev. udca actual. divulg. cient ; 25(1): e1942, ene.-jun. 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1395183

RESUMO

ABSTRACT Several aspects of the development of the peach fruit under tropical conditions are unknown, this information allows agronomic practices to be carried out with technical criteria. Therefore, the objective was to determine the different changes and phenological changes of peach fruit depending on the Growing Degree Days (GDD) in the varieties 'Dorado' and 'Rubidoux', grown in the Colombian high tropics. This study randomly selected 51 trees and 100 flowers per plant that were in full flowering for sampling every 15 days until harvest to determine physical variables such as firmness, color index of the epidermis and pulp, and chemical properties such as soluble solids, titratable acidity, and respiratory rate. From full bloom to harvest, the Dorado and Rubidoux varieties took 1081.8 GDD (153 days) and 1667.1 GDD (205 days) respectively. The firmness increased in the two cultivars during phase 1 of development, then decreased until harvest. The color index of the epidermis and pulp increased during ripening, indicating yellow tones in the two varieties. The soluble solids increased continuously, with final values of 15.9 ± 0.9 and 15.5 ± 0.3 °Brix. The acidity increased during phase 2 and then decreased during ripening. The respiratory rate decreased between phase 1 and 3, with an increase in phase 2, which is related to the lignification of the endocarp in the two cultivars. These results contribute to the understanding of the development of the two peach cultivars under tropical conditions.


RESUMEN Se desconocen varios aspectos del desarrollo del fruto de duraznero en condiciones tropicales, información que permite realizar labores agronómicas con criterio técnico, por tanto, el objetivo fue determinar los diferentes cambios fisicoquímicos y fenológicos del fruto de durazno, en función del tiempo térmico, de las variedades 'Dorado' y 'Rubidoux', cultivados en zonas de trópico alto colombiano. Se seleccionaron al azar 51 árboles y 100 flores/planta, en estado de plena floración. Cada 15 días y hasta la cosecha, se hicieron mediciones de la firmeza, el índice de color de epidermis y pulpa, los sólidos solubles, la acidez titulable y la tasa respiratoria. De plena floración a cosecha, las variedades Dorado y Rubidoux tardaron 1081,8 GDC (153 días) y 1667,1 GDC (205 días), respectivamente. La firmeza presentó un incremento en los dos cultivares durante la fase 1 de desarrollo, luego disminuyó hasta la cosecha. El índice de color de epidermis y pulpa aumentó durante la maduración, con tonalidades amarillas, en las dos variedades. Los sólidos solubles incrementaron de forma continua y en los dos cultivares, con valores finales de 15,9 ± 0,9 y 15,5 ± 0,3 °Brix. La acidez mostró un incremento durante la fase 2 y luego disminuyó durante la maduración. La tasa respiratoria decreció entre la fase 1 y 3, con un incremento en la fase 2, relacionado con la lignificación del endocarpio, en los dos cultivares. Estos resultados contribuyen al entendimiento del desarrollo de los dos cultivares de durazno, bajo condiciones tropicales.

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