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Search Results: 1 - 10 of 8281 matches for " Rey Gutiérrez Tolentino "
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Proximate Composition, Fatty Acid Profile and Mycotoxin Contamination in Several Varieties of Mexican Maize  [PDF]
Silvia Denise Pe?a Betancourt, Rey Gutiérrez Tolentino, Beatriz Schettino
Food and Nutrition Sciences (FNS) , 2017, DOI: 10.4236/fns.2017.89062
Abstract: In Mexico maize (Zea mays L.) is an important cereal due to excellent taste and nutritional value. Nutritional content and fatty acid profile has been reported in white maize, however, there are several genotypes natives (red, yellow, black, blue, pinto), and many improved hybrids maize of which little is known. Fumonisins and aflatoxins are mycotoxins present in 25% of the world’s cereals, mainly in tropical and subtropical regions around the world. This study presents the analysis of proximate composition (ash, protein, lipids), as well as mycotoxins (fumonisins and aflatoxins) and five different fatty acids, two of saturated fatty acids (palmitic and stearic) and three of polyunsaturated fatty acids (oleic, linoleic and linolenic), evaluated by Gas Chromatography and Flame Detector (GC-DF). Thirty varieties of maize (native and hybrid maize) were collected in states of central region. The total fumonisins were determined using the QuickTox TM extraction and quantificated by QuickScan fumonisins; the aflatoxins were analyzed by commercial ELISA kit. The highest protein level was 10.43 g/100g, 5.63 g/100g for fat, 1.62 g/100g for ash in hybrid maize. In native maize, the highest levels of protein and ash were 10.94 g/100g and 1.45 g/100g for pinto maize. The higher value for fat was 5.45 g/100g in yellow maize. The palmitic and stearic acids, in native maize were higher that hybrid maize, for linoleic acid and linoleinic fatty with a significant difference between native corn. Fumonisins and aflatoxins were contaminated in all genotypes of maize, in allow levels. This information obtained may be considered in maize breeding programs, industrialization processes and healthy diets.
Functional Foods, Old Age and Diabetes  [PDF]
Marta Coronado Herrera, Rey Gutiérrez Tolentino, Salvador Vega y León, Claudia Radilla Vázquez, Marcela Vazquez Francisca, María de Lourdes Ramírez Vega
Food and Nutrition Sciences (FNS) , 2015, DOI: 10.4236/fns.2015.616155
Abstract: The aim of this paper is to analyze aspects of nutrition and nourishment among elderly diabetic people. It is presented the current research of products with functional food properties that provide not only nutritional value but also other components which encourage a better quality of life during aging. In addition, it includes natural and industrialized functional foods that are commercialized and may be good for daily consumption.
Aplicación de tres métodos analíticos para la detección de suero de quesería en leche UHT comercializada en la ciudad de México
Ramírez Ayala,Acacia; Vega y León,Salvador; Prado Flores,Guadalupe; Gutiérrez Tolentino,Rey;
Interciencia , 2009,
Abstract: the presence of cheese serum was detected in ultra pasteurized milks (uht) commercialized in mexico city. this was achieved through sodium dodecyl sulphate poliacrylamide gel electrophoresis (sds-page), by high performance liquid chromatography (hplc) and by the calculation of the fourth derivative of the absorption spectrum (uv-4thds). monthly, ten (10) skimmed uht milk samples were analyzed during september, october and november, and the values obtained through the three methods were compared against those from authentic raw milk with addition of cheese serum in different amounts. the percentage of positive samples to cheese serum analyzed through electrophoresis, hplc and uv-4thds was 70.50 and 90%, respectively. the applied techniques related to the detection and estimation of the glycomacropeptide (gmp) by electrophoresis or by hplc, and the results obtained indicated that the quantification of the serum protein/total protein (ps/pt) relationship by uv-4thds was a more sensitive indicator of cheese serum additions.
Detección de suero de quesería en leches ultrapasteurizadas mexicanas mediante la cuarta derivada del espectro de absorción
Acacia Ramírez Ayala,Salvador Vega y León,Guadalupe Prado Flores,Rey Gutiérrez Tolentino
Veterinaria México , 2008,
Abstract: Se determinó la presencia de suero de quesería en leches ultrapasteurizadas (UHT) comercializadas en la Ciudad de México mediante el método de la cuarta derivada del espectro de absorción, el cual permite conocer la variación de la relación proteínas de suero/proteína total (PS/PT). La cuantifi cación de la relación PS/PT se utilizó como indicador de la adulteración con suero de quesería. El método fue estandarizado evaluando la exactitud, linealidad y repetibilidad mediante la adición de suero en concentraciones entre 0%-15% a leche cruda. Se analizaron 30 muestras de leche ultrapasteurizada descremada durante septiembre, octubre y noviembre; los valores encontrados se contrastaron con los de leche cruda adicionada con suero de quesería (0%- 15%, en niveles de 2.5%. Se encontró una diferencia marginal en la relación PS/PT para la concentración 0% entre los dos tipos de leche, mientras que el resto de las concentraciones mostró una signifi cancia alta (P < 0.01). Valores por encima de 13.5% de PS/PT expresaron adición de suero; 36.7% de las muestras de leche UHT fueron positivas a la adición de suero entre 5% y 12%. Los resultados indicaron que la cuarta derivada del espectro de absorción de la relación PS/PT fue un indicador sensible a adiciones de suero de quesería.
Organochlorine Pesticides in Infant Milk Formulas Marketed in the South of Mexico City  [PDF]
Rey Gutiérrez Tolentino, Salvador Vegay León, Beatriz Schettino Bermúdez, Guadalupe Prado Flores, María de Lourdes Ramírez Vega, Claudia Radilla Vázquez, María Radilla Vázquez, Marcela Vazquez Francisca
Food and Nutrition Sciences (FNS) , 2014, DOI: 10.4236/fns.2014.513140

The nature of organochlorine pesticides (OCP) and their physical-chemical properties exert immediate action of control on live systems, which has justified their use in agricultural practices. Their long life makes them a persistent ecological aggressor and biomagnifier. They reach foods by biotic and abiotic means, and are absorbed and accumulate in adipose tissue. In lactation processes, they are excreted in milk through the mobilization of fats. Diverse studies have identified them as neurotoxic, affecting reproductive processes, altering the immunological response and act as endocrine disruptors. An analysis was made of the content of organochlorine pesticides in twenty-one samples of infant milk formulas marketed in the south of Mexico City in 2010. The determinations were made following the protocols of the International Dairy Federation, by means of gas chromatography with electron capture detector, and the majority presence was found of α-HCH (100%), β-HCH (95.2%), γ-HCH (90.5%), aldrin (85.7%), heptachlor (80.9%) and heptachlor epoxide (80.9%) with mean values of 0.24, 0.13, 0.32, 0.62, 0.92 and 0.18 μg/kg of fat, respectively;all below the limits permitted by the Codex Alimentarius. With null or lower recurrence and in lowerquantities, the family of DDT, endrin, endrin aldehyde and the endosulphanes were quantified.

Association of Vegetable Consumption with Nutritional Status in Adolescents in Mexico City  [PDF]
Claudia Cecilia Radilla Vázquez, Salvador Vega y León, Rey Gutiérrez Tolentino, María Radilla Vázquez, Marcela Vazquez Francisca, Clemente Sierra Cortés, Marta Coronado Herrera, Juan Gabriel Rivera Martínez
Food and Nutrition Sciences (FNS) , 2016, DOI: 10.4236/fns.2016.714128
Abstract: It has been documented that increased vegetable consumption is associated with preventive effects in some public health problems such as obesity and some chronic noncommunicable diseases. The aim of this study was to determine the association of nutritional status with vegetable consumption in adolescents from Technical High Schools in Mexico City. A sample of 2368 adolescents was obtained who were applied a questionnaire of frequency food consumption and anthropometric measurements were taken, the nutritional diagnosis was obtained with Who Anthro Plus program. The data obtained were analyzed with the statistical package SPSS version 20.0 for Windows Statistics®. When the correlation of frequency consumption of vegetables with nutritional status, in the final phase, It found that teens who never ate vegetables were more likely to develop obesity (36.0% GI and 36.10% GC), compared with teens who consumed daily (8.9% GI and 2.10% GC), existing difference highly significant. The teenagers of the Technical High School in Mexico City in the intervention group presented a basal daily intake of 15.7% and after the intervention their intake increased to 21.3%. With respect to the control group it started with a daily intake of 12.6% to 14.9% increasing it. An increase was achieved in the daily consumption of vegetables in adolescents of both groups so it is concluded that the intervention was successful.
Residuos de plaguicidas organoclorados en leche de cabra de Querétaro, Querétaro, México
Guadalupe Prado Flores,Gilberto Díaz González,Rey Gutiérrez Tolentino,Salvador Vega y León
Veterinaria México , 2007,
Abstract: Se cuantifi caron los niveles de plaguicidas organoclorados (PO) y sus metabolitos en 40 muestras de leche cruda de cabra, por cromatografía gas-líquido con detector de captura de electrones (ECD Ni63). Las muestras de leche se obtuvieron de la Unidad Experimental de la Universidad Autónoma de Querétaro, durante la primavera de 2003. En todas las muestras se encontró al menos uno de los PO o sus metabolitos estudiados. Las frecuencias de ocurrencias más altas se encontraron para heptacloro y su epóxido, endosulfán I y α-HCH con 95.4%, 93.2%, 70.5% y 47.7%, respectivamente; mientras las más bajas correspondieron a p,p′-DDD, dieldrín, endrín, endosulfán II y endosulfán sulfato con 13.6%, 13.6%, 13.6%, 11.4% y 2.3%, respectivamente. Los niveles más altos se encontraron para endrín aldehído (48.20 ng/g), γ-HCH (37.75 ng/g), β-HCH (35.98 ng/g) y p,p′-DDD (31.77 ng/g). Los contenidos de PO por familia química fueron: Σ (α, β, γ, δ)-HCH: 114.74 ng/g, Σ (p,p′-DDT, p,p′-DDD, p,p′-DDE): 66.14 ng/g, Σ (ciclodiénicos): 128.90 ng/g y Σ (endosulfanes): 52.8 ng/g. La suma de heptacloro y epóxido de heptacloro (35.65 ng/g) registró la cuarta parte del límite permitido (LMR) para leche vacuna (150 ng/g).
Determination of the presence of 10 antimicrobial residues in mexican pasteurized milk
Gutiérrez Tolentino,Rey; Noa Pérez,Mario; Díaz González,Gilberto; Vega y León,Salvador; González López,Magdalena; Prado Flores,Guadalupe;
Interciencia , 2005,
Abstract: residues of 9 antimicrobial agents approved in méxico for veterinary use in dairy cattle (sulfathiazole, sulfamerazine, sulfamethazine, sulfachloropyridazine, sulfamonomethoxine, sulfamethoxazole, nitrofurazone, furaltadone, and furazolidone) and non-approved chloramphenicol residues were studied every two weeks in four commercial brands of mexican pasteurized milk (a, b, c and d) during one year (n=4×24=96). drug residues were analyzed by high pressure liquid chromatography hplc with uv detection. percentage of positive samples to sulfonamide residues were 47.2% (milk a), 58.3% (milk b), 44.7% (milk c) and 50% (milk d). sulfonamide residues ranged between 1.9 and 180μg/kg. sulfathiazole and sulfamerazine were the most common residues found. only three samples (milk b) exceeded maximum residue levels established for sulfonamides. nitrofuran residues were not detected in any milk sample. illegal chloramphenicol residues were detected in one milk sample (milk a) in levels of 27.2μg/kg.
Determinación de residuos de malatión y malaoxón en mango de las variedades Ataulfo y Tommy Atkins producidos en Chahuites, Oaxaca
Fuentes-Matus, Casibe;Vega y León, Salvador;Díaz-González, Gilberto;Noa-Pérez, Mario;Gutiérrez-Tolentino, Rey;
Agrociencia , 2010,
Abstract: the organophosphate pesticide malathion and its metabolite malaoxón cause harmful effects on the health of humans that consume foods contaminated with these molecules. the presence of residues of malathion and malaoxón was studied in mangos (mangifera indica) of the varieties ataulfo and tommy atkins produced in the municipality of chahuites, state of oaxaca, during the harvest period of 2007. the extraction system used ethyl acetate in aqueous matrix, and analytic determination by means of liquid gas chromatography with thermionic specific detector (tsd). the concentration of residues of malathion and malaoxón was determined for each variety through sampling at 1, 30 and 60 d after having applied malathion (520 g i. a. of malathion ha-1), in compliance with the phytosanitary norm (nom-023-fito) for the control of the mexican fruit fly (anastrepha ludens) on days 1 (t1) and 30 (t2), and two applications of malathion for day 60 (t3). control mangos of both varieties were used, taken from orchards free of pesticide application for 10 years. the presence of malathion was detected in 75 % and 95.6 % of the samples (n=12) of the varieties ataulfo and tommy atkins. residues of the metabolite malaoxón were detected in 83.3 % of the samples (n=12) in both varieties. no degradation was observed of either pesticide once it was present in the fruit until day 60 of the study. furthermore, the means of the residues increased in time three of the study (t3) in both varieties, after two applications of malathion.
Detección de suero de quesería en leches ultrapasteurizadas mexicanas mediante la cuarta derivada del espectro de absorción
Ramírez Ayala, Acacia;Vega y León, Salvador;Prado Flores, Guadalupe;Gutiérrez Tolentino, Rey;Pérez González, Cuauhtémoc;
Veterinaria México , 2008,
Abstract: presence of rennet whey solids in ultrapasteurized milk (uht) commercialized in mexico city was determined using fourth derivative of absorption spectrum method, which allows to know the variation in whey protein/total protein ratio (wp/tp). the quantification of wp/tp ratio was used as an indicator of adulteration with rennet whey solids. the method was standardized to evaluate the accuracy, linearity and repeatability by rennet whey addition in concentrations between 0-15%, in raw milk. thirty samples of skim ultrapasteurized milk were analyzed during september, october and november; found values were compared to the ones of raw milk added with rennet whey solids (0-15%, in levels of 2.5%). a marginal difference was found in the wp/tp ratio for the 0% concentration between the two types of milk, while the rest of the concentrations showed a high significance (p < 0.01). values above 13.5% of wp/tp showed rennet whey solids addition; 36.7% of the uht milk samples were between 5% and 12% positive to rennet whey solids addition. the results indicated that fourth derivative of the absorption spectrum of the wp/tp ratio was a sensitive indicator to rennet whey solids additions.
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