RESUMEN
Isolation and characterization of anticancer activity guided secondary metabolites of endemic Astragalus leucothrix Freyn& Bornm were aimed. Aerial parts of the plant were extracted by maceration method in the solvent system methanol-chloroform (1 : 1) at room temperature. The obtained crude extract was dissolved in purified water. Then, the extract was partitioned with n-hexane, chloroform, ethyl acetate, and n-butanol, respectively. Anticancer activity tests of all the fractions were performed against HeLa and C6 cancer cells. The chloroform fraction that has highest anticancer activity was subjected to chromatographic methods such as column chromatography and thin layer chromatography. Pentyl tetratetracontanoate (1), alfalone (2), 3,6,8-tribromoquinoline (3), and 3,6,8-tribromochromenium (4) molecules were detected from this plant for the first time. The structure determinations of the isolated molecules were elucidated by methods such as 1D and 2D NMR, HPLC - TOF / MS, and GC - MS analysis. Finally, anticancer and cytotoxic activity tests of the compounds were performed. Literature review showed that 3,6,8-tribromochromenium is a new compound. IC50 values of compound 1-2 and compound 3-4 mix were determined to be 4.50 ± 0.10, 2.81 ± 0.00, 4.33 ± 0.00 µM against C6 cell, respectively. The drug likeness properties of 1-4 were obtained by SwissADME. According to Lipinski's rule of five; 2-4 could be a new potential anticancer agent.
RESUMEN
The conjugation reaction of electrospun fibers of a mixture of whey protein isolate (WPI) and dextran using different molecular weights (40, 70, and 100 kDa) and mixing ratios was studied. This study includes the electrospinnability of a mixture of WPI and dextran, and the conjugation reaction between them via the initial stage of the Maillard reaction. The WPI-dextran fibers were characterized using optical and transmission electron microscopy. The covalent attachment of dextran to WPI was confirmed using sodium-dodecyl-sulfate-polyacrylamide gel-electrophoresis with protein and glycoprotein staining. Both 70 and 100 kDa of dextran and WPI at mixing ratios of 2 : 1 and 3 : 1 in phosphate buffer (30 mM, pH 6.5) were electrospun using needleless electrospinning. The solution concentration of the mixture was 50 wt% (33.3/37.5 wt% for dextran/16.5/12.5 wt% for WPI). The optimal conjugation conditions chosen from the experiments were a mixture of dextran (70 kDa)-WPI at 3 : 1 (75% relative humidity, 60 °C, 48 h).
Asunto(s)
Dextranos/química , Polímeros/síntesis química , Proteína de Suero de Leche/química , Técnicas Electroquímicas , Electroforesis en Gel de Poliacrilamida , Concentración de Iones de Hidrógeno , Reacción de Maillard , Peso Molecular , Polímeros/químicaRESUMEN
Thyme is a good source of antioxidant compounds but it can be contaminated by microorganisms. An experimental fluid bed ultraviolet (UV) reactor was designed for microbial decontamination of thyme samples and the effect of shortwave ultraviolet light (UV-C) radiation on antioxidant properties of thyme was studied. Samples were exposed to UV-C radiation for 16 or 64 min. UV-C treatment led to 1.04 and 1.38 log CFU/g reduction of total aerobic mesophilic bacteria (TAMB) counts. Hunter a(∗) value was the most sensitive colour parameter during UV-C treatment. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of extracts was not significantly affected by UV-C. Addition of thyme extracts at 0.15 and 0.3 µmol GAE/ml emulsion delayed the formation of lipid hydroperoxides and headspace hexanal in the 5.0%(wt) corn oil-in-water emulsion from 4 to 9 and 14 days, respectively. No significant changes in oxidation rates were observed between UV-C treated and untreated samples at same concentrations.
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Terapia por Radiofrecuencia , Thymus (Planta)/química , Rayos Ultravioleta , Antioxidantes , Oxidación-ReducciónRESUMEN
Thyme (Thymus vidgaris L.), rosemary (Rosmarinus officinalis L.), black pepper (Piper nigrum L.) and cumin (Cuminum cyminum L.) in ground form were packaged in either air or 100% N2 and γ-irradiated at 3 different irradiation levels (7kGy, 12kGy, 17kGy). Total viable bacterial count, yeast and mould count, colour, essential oil yield and essential oil composition were determined. Microbial load was not detectable after 12kGy irradiation of all samples. Irradiation resulted in significant changes in colour values of rosemary and black pepper. The discolouration of the irradiated black pepper was lower in modified atmosphere packaging (MAP) compared to air packaging. Essential oil yield of irradiated black pepper and cumin was lower in air packaging compared to MAP. Gamma-irradiation generally decreased monoterpenes and increased oxygenated compounds, but the effect was lower in MAP. Overall, spices should be irradiated under an O2-free atmosphere to minimise quality deterioration.
Asunto(s)
Cuminum/efectos de la radiación , Irradiación de Alimentos/métodos , Piper nigrum/efectos de la radiación , Rosmarinus/efectos de la radiación , Especias/análisis , Especias/efectos de la radiación , Thymus (Planta)/efectos de la radiación , Cuminum/química , Cuminum/microbiología , Embalaje de Alimentos , Rayos gamma , Piper nigrum/química , Piper nigrum/microbiología , Control de Calidad , Rosmarinus/química , Rosmarinus/microbiología , Especias/microbiología , Thymus (Planta)/química , Thymus (Planta)/microbiologíaRESUMEN
Combined effects of gamma irradiation and concentrations of O(2) (0, 5, 21%) and CO(2) (0, 50%) on survival of Escherichia coli O157:H7, Salmonella enteritidis, Listeria monocytogenes, lipid oxidation, and color changes in ready-to-cook seasoned ground beef (meatball) during refrigerated storage were investigated. Ground beef seasoned with mixed spices was packaged in varying O(2) and CO(2) levels and irradiated at 2 and 4 kGy. Irradiation (4 kGy) caused about 6 Log inactivation of the inoculated pathogens. Inactivation of Salmonella was 0.9- and 0.4-Log lower in 0 and 5% O(2), respectively, compared to 21% O(2). Irradiation at 2 and 4 kGy increased thiobarbituric acid reactive substances in meatballs by 0.12 and 0.28 mg malondialdehyde kg(-1), respectively, compared to control. In reduced-O(2) packages, radiation-induced oxidation was lower, and the initial color of an irradiated sample was maintained. Packaging with 0% + 50% CO(2) or 5% O(2) + 50% CO(2) maintained the oxidative and the color quality of irradiated meatballs during 14-day refrigerated storage. MAP with 5%O(2) + 50% CO(2) combined with irradiation up to 4 kGy is suggested for refrigerated meatballs to reduce the foodborne pathogen risk and to maintain the quality.
Asunto(s)
Dióxido de Carbono/metabolismo , Irradiación de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Rayos gamma , Productos de la Carne/microbiología , Oxígeno/metabolismo , Animales , Antibacterianos/farmacología , Carga Bacteriana , Frío , Relación Dosis-Respuesta en la Radiación , Escherichia coli/crecimiento & desarrollo , Escherichia coli/efectos de la radiación , Microbiología de Alimentos/métodos , Listeria monocytogenes/crecimiento & desarrollo , Listeria monocytogenes/efectos de la radiación , Malondialdehído/metabolismo , Oxidación-Reducción , Refrigeración , Salmonella enteritidis/crecimiento & desarrollo , Salmonella enteritidis/efectos de la radiación , Tiobarbitúricos/metabolismo , Factores de TiempoRESUMEN
OBJECTIVE: The purpose of our study was to evaluate the diagnostic value of an imaging protocol that combines dynamic contrast-enhanced MRI (DCE-MRI) and diffusion-weighted imaging (DWI) in patients with suspicious breast lesions and to determine if additional information provided by DWI improves the diagnostic value of breast MRI. MATERIALS AND METHODS: Eighty-four patients with breast tumors (37 benign, 47 malignant) underwent DCE-MRI and DWI before biopsy. Morphologic and kinetic analyses were performed on DCE-MRI and findings were classified according to the BI-RADS lexicon. Apparent diffusion coefficient (ADC) values were calculated from the DWI. The ADCs of the benign and malignant lesions were compared. For the combined MRI protocol, morphologic kinetic features and ADCs were evaluated together. Diagnostic values of DCE-MRI, DWI, and combined MRI were calculated. RESULTS: Median ADCs of the benign and malignant lesions were 1.26 × 10(-3) mm(2)/s and 0.75 × 10(-3) mm(2)/s, respectively. Cutoff value of 0.92 × 10(-3) mm(2)/s for ADC provided 91.5% sensitivity and 86.5% specificity. DCE-MRI alone showed 97.9% sensitivity and 75.7% specificity. The combination of DCE-MRI with DWI provided 95.7% sensitivity and 89.2% specificity. The specificity of breast MRI improved by 13.5% (p = 0.063) without a significant decrease in the sensitivity (p = 1.000). CONCLUSION: The combination of DWI and DCE-MRI has the potential to increase the specificity of breast MRI.
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Neoplasias de la Mama/diagnóstico , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Biopsia , Neoplasias de la Mama/patología , Medios de Contraste , Diagnóstico Diferencial , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Humanos , Persona de Mediana Edad , Compuestos Organometálicos , Curva ROC , Sensibilidad y Especificidad , Estadísticas no ParamétricasRESUMEN
UNLABELLED: Meatballs were prepared by mixing ground beef and spices and inoculated with E. coli O157:H7, L. monocytogenes, and S. enteritidis before packaged in modified atmosphere (3% O2 + 50% CO2 + 47% N2) or aerobic conditions. The packaged samples were irradiated at 0.75, 1.5, and 3 kGy doses and stored at 4 °C for 21 d. Survival of the pathogens, total plate count, lipid oxidation, color change, and sensory quality were analyzed during storage. Irradiation at 3 kGy inactivated all the inoculated (approximately 106 CFU/g) S. enteritidis and L. monocytogenes cells in the samples. The inoculated (approximately 106 CFU/g) E. coli O157:H7 cells were totally inactivated by 1.5 kGy irradiation. D¹°-values for E. coli O157:H7, S. enteritidis, and L. monocytogenes were 0.24, 0.43, and 0.41 kGy in MAP and 0.22, 0.39, and 0.39 kGy in aerobic packages, respectively. Irradiation at 1.5 and 3 kGy resulted in 0.13 and 0.36 mg MDA/kg increase in 2-thiobarbituric acid-reactive substances (TBARS) reaching 1.02 and 1.49 MDA/kg, respectively, on day 1. Irradiation also caused significant loss of color and sensory quality in aerobic packages. However, MAP effectively inhibited the irradiation-induced quality degradations during 21-d storage. Thus, combining irradiation (3 kGy) and MAP (3% O2 + 50% CO2 + 47% N2) controlled the safety risk due to the potential pathogens and maintained qualities of meatballs during 21-d refrigerated storage. PRACTICAL APPLICATION: Combined use of gamma irradiation and modified atmosphere packaging (MAP) can maintain quality and safety of seasoned ground beef (meatball). Seasoned ground beef can be irradiated at 3 kGy and packaged in MAP with 3% O2 + 50% CO2 + 47% N2 gas mixture in a high barrier packaging materials. These treatments can significantly decrease risk due to potential pathogens including E. coli O157:H7, L. monocytogenes, and S. enteritidis in the product. The MAP would reduce the undesirable effects of irradiation on quality, and extend the shelf life of the product for up to 21 d at 3 °C.
Asunto(s)
Escherichia coli O157/crecimiento & desarrollo , Irradiación de Alimentos , Embalaje de Alimentos , Listeria monocytogenes/crecimiento & desarrollo , Productos de la Carne/análisis , Productos de la Carne/microbiología , Salmonella enteritidis/crecimiento & desarrollo , Animales , Dióxido de Carbono/efectos adversos , Dióxido de Carbono/análisis , Dióxido de Carbono/metabolismo , Bovinos , Recuento de Colonia Microbiana , Escherichia coli O157/aislamiento & purificación , Escherichia coli O157/metabolismo , Escherichia coli O157/efectos de la radiación , Irradiación de Alimentos/efectos adversos , Enfermedades Transmitidas por los Alimentos/prevención & control , Rayos gamma/efectos adversos , Humanos , Peroxidación de Lípido/efectos de la radiación , Listeria monocytogenes/metabolismo , Listeria monocytogenes/efectos de la radiación , Viabilidad Microbiana/efectos de la radiación , Oxígeno/efectos adversos , Oxígeno/análisis , Oxígeno/metabolismo , Pigmentación/efectos de la radiación , Refrigeración , Salmonella enteritidis/metabolismo , Salmonella enteritidis/efectos de la radiación , Sensación , EspeciasRESUMEN
We report a case of retained surgical sponge in the breast with its sonographic and magnetic resonance (MR) imaging findings. Striped and spotted low signal intensity structures seen within the lesion on T2 weighted MR imaging was characteristic. Sonographic examination also was helpful with the appearance of strong posterior acoustic shadowing at the lesion. It is extremely rare, to see a gossypiboma in the breast. A high degree of suspicion and imaging findings are very important for the diagnosis.
RESUMEN
Dense-phase carbon dioxide (CO2) treatments in a continuous flow through system were applied to apple cider to inactivate Escherichia coli (ATCC 4157). A response surface design with factors of the CO2/product ratio (0, 70, and 140 g/kg), temperature (25, 35, and 45 degrees C), and pressure (6.9, 27.6, and 48.3 MPa) were used. E. coli was very sensitive to dense CO2 treatment, with a more than 6-log reduction in treatments containing 70 and 140 g/kg CO2, irrespective of temperature and pressure. The CO2/product ratio was the most important factor affecting inactivation rate of E. coli. No effect of temperature and pressure was detected because of high sensitivity of the cells to dense CO2. Dense CO2 could be an alternative pasteurization treatment for apple cider. Further studies dealing with the organoleptic quality of the product are needed.
Asunto(s)
Bebidas/microbiología , Dióxido de Carbono/farmacología , Seguridad de Productos para el Consumidor , Escherichia coli/efectos de los fármacos , Conservación de Alimentos/métodos , Recuento de Colonia Microbiana , Relación Dosis-Respuesta a Droga , Escherichia coli/crecimiento & desarrollo , Humanos , Malus/microbiología , Presión , Control de Calidad , Gusto , TemperaturaRESUMEN
The effects of reduced-O2 and elevated-CO2 modified atmospheres (MAs) and abusive temperatures on the growth and survival of E. coli O157:H7, yeast, and molds and on changes in the visual quality of fresh-cut apples were evaluated. High-CO1 and low-O2 (> or = 15% and < 1%, respectively) atmospheres inhibited the growth of the pathogen on apple slices at 15 and 20 degrees C. However, the population of the pathogen increased by 1 log cycle after 2 weeks of storage in air. The high-CO2 MA resulted in the inhibition of yeast and mold growth, less browning, and better visual quality than did air and ambient-CO2 atmospheres. The results of this study confirm that E. coli O157:H7 can grow on apple slices in air. These results also show that these organisms survive but are inhibited in MAs with high CO2 levels at abusive temperatures. An MA can increase the shelf life of fresh-cut apples by improving retention of visual quality and inhibiting yeast and molds. Thus, contamination of minimally processed apples with E. coli O157:H7 can be a safety issue for both air- and MA-packaged cut apples.
Asunto(s)
Escherichia coli O157/crecimiento & desarrollo , Embalaje de Alimentos/métodos , Hongos/crecimiento & desarrollo , Malus/microbiología , Levaduras/crecimiento & desarrollo , Dióxido de Carbono , Recuento de Colonia Microbiana , Microbiología de Alimentos , Conservación de Alimentos , Oxidación-Reducción , Oxígeno , TemperaturaRESUMEN
The effects of controlled-atmosphere (CA) storage on the firmness, respiration rate, quality, weight loss, total phenolics and flavonoids contents, and total antioxidant activities of the Pilgrim and Stevens cultivars of cranberries (Vaccinium macrocarpon Aiton) have been studied during storage in atmospheres of 2, 21, and 70% O(2) with 0, 15, and 30% CO(2) (balance N(2)); and 100% N(2) at 3 degrees C. Elevated CO(2) concentrations decreased bruising, physiological breakdown, and decay of berries, thereby reducing fruit losses. Respiration and weight loss of fruits decreased, but fruit softening increased, at higher CO(2) concentrations. Accumulations of acetaldehyde, ethanol, and ethyl acetate varied by cultivar and storage atmosphere but were generally highest in the 2 and 70% O(2) and 100% N(2) atmospheres and increased in response to elevated CO(2) concentrations. Overall, the 30% CO(2) plus 21% O(2) atmosphere appeared optimal for the storage of cranberries. Sensory analysis is required, however, to confirm that accumulations of fermentation products at this atmosphere are acceptable for consumers. Stevens fruits had a higher phenolics content and total antioxidant activity than Pilgrim fruits. The storage atmosphere did not affect the content of total phenolics or flavonoids. However, the total antioxidant activity of the fruits increased overall by about 45% in fruits stored in air. This increase was prevented by storage in 30% CO(2) plus 21% O(2).
Asunto(s)
Antioxidantes/análisis , Ambiente Controlado , Conservación de Alimentos , Frutas/química , Control de Calidad , Vaccinium macrocarpon/química , Acetaldehído/análisis , Acetatos/análisis , Dióxido de Carbono/administración & dosificación , Dióxido de Carbono/metabolismo , Etanol/análisis , Fermentación , Flavonoides/análisis , Frutas/metabolismo , Frutas/microbiología , Hongos/metabolismo , Oxígeno/administración & dosificación , Oxígeno/metabolismo , Fenoles/análisis , Vaccinium macrocarpon/metabolismo , Vaccinium macrocarpon/microbiologíaRESUMEN
Fresh-cut potatoes were treated with an antibrowning solution (l-cysteine-citric acid mixture) and chlorine solutions, and then packaged under a modified atmosphere. The effect of these treatments on the microbiology of the potatoes was evaluated. Dipping the potato strips in sodium hypochlorite solutions (100 and 300 ppm) resulted in higher microbial populations during the storage period, while potatoes treated with the antibrowning solution combined with modified-atmosphere packaging showed only a slight increase. Modified-atmosphere packaging had no significant-effect on the microbial population compared to nonpackaged samples. The predominant organisms were Pseudomonas fluorescens , along with other Pseudomonas species, and Vibrio fluvialis .