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1.
Vitae (Medellín) ; 27(1): 1-8, 2020. Ilustraciones
Artigo em Inglês | LILACS, COLNAL | ID: biblio-1117156

RESUMO

Background: The determination of polyphenols in cocoa beans allows the establishing of antioxidant properties of great benefit to this product. Objectives: Optimization of the ultrasound-assisted extraction method to determine the content of polyphenols in cocoa beans. Methods: Two experiments design stages were carried out to optimize the ultrasound-assisted extraction process of polyphenols from the cocoa bean. In the first experiment design stage, the adequate extraction solvent was determined; for this purpose, five types of solvents were evaluated through a completely random design unrestricted (CRD). In the second experiment stage, a central composite design 22 + star point (with two central points) was used, which was evaluated using the response surface methodology to determine the influence of the temperature, time, and solute / solvent ratio. Results: The experiment found that acetone: water: acetic acid (70: 29.5: 0.5) mixturee, leads to a greater amount of total extracted phenols measured for the Folin-Ciocalteu method. Analysis of variance (ANOVA) found that six significant effects that influence the response variable (total phenols extracted). The main effects were of the three factors and three of their interactions. Conclusions: After the optimizing said factors, an optimal point was found: 39.3 ° C of temperature, 74.5 minutes, and 22.8 mL of solvent per gram of cocoa sample.


Antecedentes: La determinación de polifenoles en granos de Cacao permite establecer propiedades antioxidantes de gran valor agregado a este producto. Objetivo: Optimización del método de extracción asistida con ultrasonido para determinar el contenido de polifenoles en granos de Cacao. Métodos: Se realizaron dos etapas del diseño experimental para la optimización del proceso de extracción de polifenoles del grano de cacao por ultrasonido. En la primera etapa se determinó el solvente de extracción más adecuado evaluando cinco tipos de solventes, mediante un diseño completamente al azar sin restricciones (DCA). En la segunda etapa experimental, se usó un diseño central compuesto 22 + estrella (con dos puntos centrales), que se evaluó mediante la metodología de superficie de respuesta para determinar la influencia de los factores Temperatura, tiempo y relación soluto/solvente. Resultados: Se determinó que la mezcla acetona: agua: ácido acético (70:29.5:0.5) extrae la mayor cantidad de fenoles totales cuantificados por el método de Folin-Ciocalteu. Mediante la aplicación de un análisis ANOVA, se encontró que seis efectos significativos influyen sobre la variable de respuesta (fenoles totales), estos incluyen los efectos principales de los tres factores y tres de sus interacciones. Conclusiones: Después de la optimización de dichos factores se encontró un punto óptimo que corresponde a 39.3 °C de temperatura, 74.5 minutos y 22.8 mL de solvente por gramo de muestra de cacao.


Assuntos
Humanos , Cacau , Polifenóis , Ultrassom , Otimização de Processos
2.
Front Genet ; 3: 229, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23130019

RESUMO

Cancer is a leading cause of death worldwide. The cancer incidence rate in Chile is 133.7/100,000 inhabitants and it is the second cause of death, after cardiovascular diseases. Most of the antineoplastic drugs are metabolized to be detoxified, and some of them to be activated. Genetic polymorphisms of drug-metabolizing enzymes can induce deep changes in enzyme activity, leading to individual variability in drug efficacy and/or toxicity. The present research describes the presence of genetic polymorphisms in the Chilean population, which might be useful in public health programs for personalized treatment of cancer, and compares these frequencies with those reported for Asian and Caucasian populations, as a contribution to the evaluation of ethnic differences in the response to chemotherapy. We analyzed 23 polymorphisms in a group of 253 unrelated Chilean volunteers from the general population. The results showed that CYP2A6*2, CYP2A6*3, CYP2D6*3, CYP2C19*3, and CYP3A4*17 variant alleles are virtually absent in Chileans. CYP1A1*2A allele frequency (0.37) is similar to that of Caucasians and higher than that reported for Japanese people. Allele frequencies for CYP3A5*3(0.76) and CYP2C9*3(0.04) are similar to those observed in Japanese people. CYP1A1*2C(0.32), CYP1A2*1F(0.77), CYP3A4*1B(0.06), CYP2D6*2(0.41), and MTHFR T(0.52) allele frequencies are higher than the observed either in Caucasian or in Japanese populations. Conversely, CYP2C19*2 allelic frequency (0.12), and genotype frequencies for GSTT1 null (0.11) and GSTM1 null (0.36) are lower than those observed in both populations. Finally, allele frequencies for CYP2A6*4(0.04), CYP2C8*3(0.06), CYP2C9*2(0.06), CYP2D6*4(0.12), CYP2E1*5B(0.14), CYP2E1*6(0.19), and UGT2B7*2(0.40) are intermediate in relation to those described in Caucasian and in Japanese populations, as expected according to the ethnic origin of the Chilean population. In conclusion, our findings support the idea that ethnic variability must be considered in the pharmacogenomic assessment of cancer pharmacotherapy, especially in mixed populations and for drugs with a narrow safety range.

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