EVALUACIÓN DE LA TOXICIDAD INDUCIDA POR SUCRALOSA EN Cyprinus carpio Y DETERMINAR SU EFECTO EN LAS PROPIEDADES FISICOQUÍMICAS Y TEXTURALES

Tesis de doctoradoLa sucralosa es un edulcorante artificial relativamente nuevo y considerado seguro para el consumo humano, sin embargo, los efectos en el ecosistema aún no han sido estudiados a profundidad. Estudios de este tipo de edulcorantes han demostrado que produce estrés oxidativo generando daño a nivel proteico; por lo que el objetivo del presente estudio fue determinar los productos de oxidación mediante el grado lipoperoxidación, contenido de hidroperóxidos y proteínas carboniladas, así como las propiedades fisicoquímicas y texturales en el músculo de Cyprinus carpio (carpa común). Los resultados del estudio demostraron que la exposición de la especie a sucralosa (0.05 y 155 μg/L) durante diferentes tiempos (12, 24, 48, 72 y 96 horas) produjo un aumento en el nivel de lipoperoxidación (LPX), el contenido de proteínas carboniladas (PCC) e hidroperóxidos (HPC), asimismo, las enzimas antioxidantes evaluadas superóxido dismutasa (SOD) y catalasa (CAT) se modifican significativamente con respecto al control en sangre, hígado, branquias, cerebro y músculo, siendo éste último el que sufre diferentes tipos de alteraciones a causa de la oxidación proteica por la presencia del xenibiótico, causando cambios significativos con respecto al control en pH, acidez, solubilidad, capacidad de retención de agua (CRA) y formación de grupos sulfhidrilo, viéndose afectados también los parámetros de textura, modificando los atributos sensoriales del alimento

Effect of lactic acid bacteria on the textural properties of an edible film based on whey, inulin and gelatin

This study was aimed to evaluate the effects of different components and the addition of probiotic bacteria of lactic acid bacteria (LAB, Lactobacillus casei) on the physicochemical and textural characteristics of edible films using a response surface Box-Behnken design. The edible films were made of the following components: Whey (8%), glycerol (6%), inulin (0 to 4%), gelatin (2 to 5%) and probiotics (0 to 2%). The addition of LAB significantly affected the pH, viscosity, luminosity, hardness and Young's modulus of the films. However, all formulations presented physicochemical and textural characteristics suitable for the survival of lactic acid bacteria during storage. Formulas 10 and 3 with a composition of 2% inulin, 3.5% gelatin and 1% probiotic, demonstrated higher responses to pH, viscosity, luminosity, hardness and Young's modulus, whereas formulas 14 and 12 exhibited lower responses to the above-mentioned features but proved the most resilient. Therefore, edible films with added probiotic bacteria could be applied to a variety of foods and to increase consumer choice.Keywords: Edible film, lactic acid bacteria, inulin, gelatin, wheyAfrican Journal of Biotechnology Vol. 12(19), pp. 2659-266

Effects of peppermint extract and chitosan-based edible coating on storage quality of common carp (Cyprinus carpio) fillets

Artículo internacional en revista indizadaEdible coatings have recently been developed and applied to different food matrices, due to their numerous benefits, such as increasing the shelf life of foods, improving their appearance, being vehicles of different compounds, such as extracts or oils of various spices that have antioxidant and antimicrobial activity, as well as being friendly to the environment. The objective of this research was to develop a new edible coating based on chitosan enriched with peppermint extract and to evaluate its effectiveness to inhibit microbial development in vitro and improve both the quality and shelf life of common carp (Cyprinus carpio) during refrigerated storage (4 ± 1 C). Three treatments were used: edible coating (C + EC), edible coating +, 5% chitosan (C + ECCh) and edible coating + 1.5% chitosan + 10% peppermint (C + ECChP). Prior the coating carp fillets; the antibacterial activity and antioxidant capacity were evaluated in the peppermint extract and coating solutions. After coating and during storage, the following were determined on the fillet samples: microbiological properties, observed for ECP, an inhibition halo of 14.3 mm for Staphylococcus aureus, not being the case for Gram-negative species, for ECCh, inhibition halos of 17.6 mm, 17.1 mm and 16.5 mm for S. aureus, Salmonella typhimurium and Escherichia coli, respectively; for the ECChP, inhibition halos for S. aureus, S. typhimurium and E. coli of 20 mm, 17 mm and 16.8 mm, respectively. For the physicochemical characteristics: an increase in solubility was observed for all treatments during storage, reaching 46.7 mg SN protein/mg total protein for the control, and values below 29.1 mg SN protein/mg total protein (p C + ECCh > C + ECChP, respectively at the end of storage. For the pH, maximum values were obtained for the control of 6.4, while for the fillets with EC a maximum of 5.8. For TVB-N, the fillets with different CE treatments obtained values (p C + E C > C + ECCh > C + ECChP respectively). Total phenolic compounds in the aqueous peppermint extract were 505.55 mg GAE/100 g dried leaves, with 98.78% antioxidant capacity in the aqueous extract and 81.88% in the EC. Biomolecule oxidation (hydroperoxide content) had a significant increase (p < 0.05) in all treatments during storage, 1.7 mM CHP/mg protein in the control, to 1.4 in C + EC, 1.27 in C + ECCh and 1.16 in C + ECChP; TBARS assay values increased in the different treatments during refrigerated storage, with final values of 33.44, 31.88, 29.40 and 29.21 mM MDA/mg protein in the control; C + EC; C + ECCh and C + ECChP respectively. In SDS -PAGE a protective effect was observed in the myofibrillar proteins of fillets with ECChP). The results indicate that the C + ECCh and C + ECChP treatments extend the shelf life of 3–5 days with respect to microbiological properties and 4–5 days with respect to physicochemical characteristics. A reduction in lipid and protein oxidation products was also observed during refrigerated storage. With these findings, this is considered a promising method to increase the shelf life of fish fillets combined with refrigeration and we are able to recommend this technology for the fish processing industry.Consejo Nacional de Ciencia y Tecnologí

CARACTERIZACIÓN OLFATOMÉTRICA Y SENSORIAL DE LOS COMPUESTOS RESPONSABLES DE AROMA EN EL LICOR DE MANZANA DE TENANGO DEL VALLE, ESTADO DE MÉXICO

En contraste, otros licores son menos conocidos al exterior, pero al interior de las comunidades donde se producen, son parte importante no sólo de la actividad económica, sino también de la identificación social y cultural de los habitantes por su comunidad. Además, son elaborados de manera artesanal, lo que hace que tengan un valor agregado al ser diferentes a aquéllos que se encuentran disponibles en el mercado, siendo así un atractivo para los visitantes. El mismo trabajo, evidenció que, específicamente en el municipio de Tenango del Valle, se produce un licor de manzana desde 1907 siguiendo una receta familiar. Se trata de una labor familiar pero que también genera empleo en la comunidad donde se elaboran. Los involucrados se encargan desde reunir las manzanas de los cerros locales hasta que el producto final se deposita para ser añejado dentro de barricas de roble blanco. Con respecto a este punto, algunas de las barricas usadas en este proceso provienen del estado de Zacatecas y otras, según reportó la familia productora, de la antigua fábrica del refresco de manzana que existió en la ciudad de Toluca. Las barricas que se usaron en 1907 son las mismas que se utilizan actualmente. Las barricas se reparan con un mes de anticipación al inicio de la producción: se llenan de agua para que la madera se hinche, se lavan con agua y asiento del vinagre de manzana al que llaman “madre”. Para finalizar con la reparación, se utiliza martillo y un cincel especial para ajustarlas y las posibles fisuras se tapan con brea o cera de cebo.En el trabajo de campo del proyecto de investigación “Estudio sobre la aceptación y preferencia de licores de naranja artesanales producidos en el Valle de Toluca” – PROMEP FE19/2009(103.5/09/4195), se detectó que entre los licores de fruta, aquél de naranja del municipio de Toluca se produce de manera semi-industrial y es uno de los más conocidos dentro y fuera del mismo vall

Amoxicillin in the Aquatic Environment, Its Fate and Environmental Risk

Amoxicillin is a broad-spectrum antibiotic widely used for treating both human and animal diseases, and it belongs to a group that are excreted unchanged within urine and faeces; therefore, it is possible to find traces of this drug or its degradation products in environmental water bodies. In water, it is rapidly degraded by biotic and abiotic factors, yielding different intermediate products; these are suspected of being more resistant to degradation, and potentially more toxic, than the parent compound. In the water bodies, these compounds may produce toxic effects on the aquatic organisms from different trophic levels and produce an ecological imbalance. Amoxicillin may bioaccumulate in fish muscle tissues, with the possibility of the occurrence of these drugs in food, leading to a passive consumption of this antibiotic resulting in undesirable effects on consumer health such as immunoallergic responses. However, the main problem related with the presence of this antimicrobial compounds in fish tissues is the possibility of inducing bacterial resistance genes. At present, the available scientific knowledge is less than what is needed to fully assess the risks that amoxicillin pose to the environment, and it is still necessary to conduct large amount of research works before a thorough understanding of this severe environmental issue

Partial typification of artisanal sausages in Toluca City: Green chorizo

Chorizo verde is a traditional sausage that forms part of the culinary heritage from the Valle de Toluca, however its morphologic and physicochemical basic characteristics are unknown. The aim of this study was to analyze some morphological (caliber and length) and physicochemical (pH, aw, L * a * b *) parameters of this traditional sausage, through samples obtained from 14 establishments, including: traditional markets (n=8), establishments specializing in the sale of traditional meat products (n =3) and supermarkets (n=3) in Toluca city. It was found that caliber, aw, and L * and b * not showed significant difference among the sausages analyzed (P>0.05). However, the length, pH and a* showed a significant difference (P<0.05) with respect to the type of establishment where it was offered. The green chorizo that is sold in the city of Toluca has features well-defined: length (9.81 cm), caliber (35.6 mm), aw (0.94), pH (4.7), besides L * (46.12), a * (- 8.32) and b * (16.24) that makes of this traditional meat product a food that should be characterized integrally

Optimization of the physic, optical and mechanical properties of a composite edible films of gelatin, whey protein and chitosan

Artículo indizadoThe aim of this work was to evaluate the effect of the concentration of gelatin (G) (3–6 g), whey protein (W) (2.5–7.5 g) and chitosan (C) (0.5–2.5 g) on the physical, optical and mechanical properties of composite edible films (CEFs) using the response surface methodology (RSM), as well as optimizing the formulation for the packaging of foods. The results of the study were evaluated via first‐ and second‐order multiple regression analysis to obtain the determination coefficient val‐ ues with a good fit (R ˃ 0.90) for each of the response variables, except for the values of solubility and b*. The individual linear effect of the independent variables (the concentrations of gelatin, whey protein and chitosan) significantly affected (p ≤ 0.05) the water vapor permeability (WVP), strength and solubility of the edible films. The WVP of the edible films varied from 0.90 to 1.62 × 10−11 g.m/Pa.s.m2, the resistance to traction varied from 0.47 MPa to 3.03 MPa and the solubility varied from 51.06% to 87%. The optimized values indicated that the CEF prepared with a quantity of 4 g, 5 g and 3 g of gelatin, whey protein and chitosan, respectively, provided the CEF with a smooth, continuous and transparent surface, with L values that resulted in a light‐yellow hue, a lower WVP, a maximum strength (resistance to traction) and a lower solubility. The results revealed that the optimized formulation of the CEF of G–W–C allowed a good validation of the prediction model and could be applied, in an effective manner, to the food packaging industry, which could help in miti‐ gating the environmental issues associated with synthetic packaging materials.Consejo Nacional de Ciencia y Tecnologí

Evaluation of physicochemical, functional and textural properties of rainbow trout (Oncorhynchus mykiss) stored at low temperatures

The physicochemical and functional behaviour of rainbow trout stored at 4 and -20°C for nine days and six months, respectively, were investigated. The combined effect of proteolytic activity and physicochemical changes in the muscle (pH, solubility and proteolytic activity) altered the molecular structure of the proteins. SDS-PAGE showed the degradation of myosin and the formation of peptides of low molecular weight, causing an increase in solubility, which is correlated with changes in the functional properties of meat (water retention, capacity of emulsification and ability of gelling). In a gel obtained from the stored samples, the solubility had an effect on the distribution of the water gel, and significant differences (P&lt;0.05) in colour and texture parameters were observed during storage. Regarding correlation analysis, during cooling, all variables studied were dependent on each other, however, in freezing, the correlation diminished in variables such as hardness, solubility and CRA. Surplus meat of trout according to the time of cold storage, can be incorporated into technological processes up to two days at a storage temperature of 4°C and three months at - 20°C, thus could contribute to the functional and textural properties of commercial meat products, generating a value liked trout producers. After this time of storage, the trout flesh can be consumed in the conventional way.Keywords: Rainbow trout, refrigeration, freezing, texture.African Journal of Biotechnology Vol. 12(32), pp. 5087-509

Retos actuales de la farmacia

Retos actuales de la farmacia es un proyecto que está coordinado por Leobargo Manuel Gómez Oliván y un equipo de investigadores que forman parte del claustro de la Facultad de Química en el área de posgrado, ellos han incentivado el espíritu investigador y científico de los estudiantes adscritos al programa para adentrarse en el ámbito farmacéutico. Los capítulos que conforman esta edición son el reflejo de la actividad académica desarrollada en este posgrado en las diferentes áreas de acentuación que lo conforman: farmacia molecular, farmacia social y tecnología farmacéutica

Actividad antioxidante e inhibidora de glucosidasa y amilasa de tres variedades de cebolla (Allium cepa L.)

The onion (Allium cepa L.) has been cultivated for thousands of years and is an important component of human diet. Recent studies suggest that onion can be used to reduce or prevent health problems such as asthma, cardiovascular diseases and diabetes due to its high antioxidant effect. Extract aqueous and ethanolic from three (purple, yellow and white) varieties of onion were studied for their total phenolic content, capacity and inhibitory activity against á-glucosidase and á- amylase. The total phenolic content varied between 6.59 to 9.25 mg/100 g and 24.3 a 42.7 mg/100 g the antioxidant capacity expressed as the percentage of inhibition of DPPH- radical ranged from 46.8 to 89.2% and 20.4% to 39.6% for ethanolic and aqueous extracts respectively. All ethanolic extracts showed capacity of inhibition for á-glucosidase y á-amylase from 58% to 34% and 33% to 22% respective while the aqueous extracts showed less effectiveness. Among the extracts, ethanolic extract of purple onion have the maximum concentration of total phenolic compounds, the highest antiradical capacity and á-glucosidase inhibition. Differences in free-radical scavenging and inhibition appeared to be dependent on the unique profile of phenolic compounds in each variety.La cebolla (Allium cepa L.) ha sido cultivada durante miles de anos y es utilizada como un componente importante en la dieta del ser humano. Estudios recientes sugieren que su consumo puede reducir o prevenir problemas de salud como asma, enfermedades cardiovasculares y diabetes, debido a sus efectos antioxidantes. En este estudio se determino el contenido de compuestos fenolicos totales, la capacidad antiradical y la inhibicion de las enzimas �¿-glucosidasa y �¿-amilasa de extractos acuosos y etanolicos de tres variedades de cebolla (blanca, amarilla y morada). El contenido de compuestos fenolicos totales vario de 6.59 a 9.25 mg/100 g y la actividad antiradical expresada como % DPPH- se encontro entre 20.4% a 39.6% y de 46.8 a 89.2% para los extractos acuosos y etanolicos respectivamente. Todos los extractos etanolicos fueron capaces de inhibir la actividad �¿-glucosidasa y �¿-amilasa de 58% a 34%% y 33 y 22% respectivamente, mientras que los extractos acuosos fueron menos efectivos. Entre los extractos estudiados, el extracto etanolicos de cebolla morada presenta la mayor concentracion de compuestos fenolicos totales y la mayor actividad antiradical e inhibidora de �¿-glucosidasa. Las diferencias encontradas entre la concentracion de compuestos fenolicos y las distintas actividades estudiadas parecen depender del perfil unico de compuestos fenolicos que posee cada variedad de cebolla