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La obesidad es una enfermedad muy común en el mundo, uno de los factores principales que provocan el desarrollo de esta enfermedad es la alta ingesta de calorías (encontradas mayormente en comida rápida o alta en calorías) comparado con el gasto energético, esto debido a que se encuentra fácilmente a nuestro alcance, otra causa que provoca este padecimiento es la vida sedentaria y la falta de conocimiento sobre el consumo de estos productos a largo plazo, México, en especial, ocupa los primeros lugares en población con este padecimiento, esto, como ya se mencionó anteriormente, se debe al estilo de vida, sedentarismo, malos hábitos, dietas hipercalóricas, falta de conocimiento sobre el tema, entre otras. Como bien sabemos, esta enfermedad trae consigo una extensa lista de secuelas e incluso el desarrollo de más enfermedades, es por ello que se debe prestar atención desde los primeros síntomas, con relación a ello también se ha estudiado a los microorganismos que habitan nuestra microbiota intestinal (MI) y la disbiosis, para conocer su papel en este padecimiento. Hoy en día, la obesidad es un tema de interés para el mundo, y por consiguiente es necesaria una revisión para conocer cómo la MI influye en ella. Se ha estudiado el consumo de probióticos, su mecanismo de acción, y cual es la función del consumo de estos con relación a la obesidad. Se necesitan diversos estudios para comprobar que los probióticos contribuyen positivamente en la obesidad.

La obesidad es un problema de salud pública en México, debido a la alta prevalencia en la población, sus tratamientos actuales van desde nutricional, farmacológico hasta quirúrgico. A pesar de las posibilidades que existen para el tratamiento de esta enfermedad, la mayoría de las personas con esta condición no obtienen resultados satisfactorios. Los estudios han relacionado los compuestos bioactivos como una alternativa en la prevención de enfermedades, entre ellas la obesidad, por lo que el uso de un compuesto bioactivo que brinde beneficios tendría un gran impacto en la población. Entre estos compuestos se encuentran las saponinas que son metabolitos secundarios de las plantas y se les han atribuido múltiples beneficios en el tratamiento de la obesidad, como participación en hormonas reguladoras del apetito, inhibición de enzimas lipídicas, por mencionar algunos, por lo que la evidencia científica sugiere su uso como coadyuvantes. en el tratamiento de la obesidad.

El género Capsicum es originario de América Latina y se expandió a otros continentes mediante intercambio de especias. Su fruto se utiliza fresco o seco para aportar color, sabor y olor a platillos, ensaladas y salsas. Posee gran relevancia comercial a nivel mundial, siendo los principales países productores China, México y Turquía. Existen cinco especies domesticadas que son: C. baccatum, C. chinense, C. pubescens, C. frutescens y C. annuum. En general, los frutos de Capsicum disponen de gran variedad de tamaños y formas, y de acuerdo a su estado de madurez presentan cambios en las tonalidades, que van del verde a tonos amarillos, rojos y rojos intensos. Los frutos poseen compuestos bioactivos que pueden proveer efectos benéficos en la salud. El objetivo del presente trabajo fue realizar una revisión sobre los compuestos bioactivos de las diferentes especies domesticadas del género Capsicum y sus recientes aplicaciones clínicas. Debido a los componentes bioactivos de las especies de Capsicum, los estudios demuestran efectos benéficos en la prevención y tratamiento sobre enfermedades no transmisibles, efectos antiinflamatorios, control de peso, cardiovasculares, antidiabéticos, gastrointestinales y cancerígenos. Las especies de Capsicum tienen un notable papel en el campo médico debido a su capacidad de modular y modificar diversos procesos a nivel biológico.

Antecedentes: Durante la obesidad hay un aumento del estrés oxidativo que resulta en el desarrollo de diferentes enfermedades, por lo que los antioxidantes se pueden utilizar para prevenir el daño oxidativo. El objetivo de este estudio fue analizar el efecto de los antioxidantes del extracto de guayaba sobre la reducción del daño oxidativo en diferentes órganos de ratas obesas. Métodos: Se realizaron dos extracciones para obtener el extracto de guayaba (EG), la primera con metanol y la segunda con acetona, ambas fueron mezcladas y se analizó la actividad y el contenido antioxidantes, el EG se concentró y se utilizó en ratas macho Wistar obesas. Tres grupos de 8 animales cada uno se formaron y alimentaron con una dieta normal (Ct), una dieta alta en grasas (grupo AG) y una dieta alta en grasas enriquecido con extracto de fruta de guayaba (AG+EG) durante 4 meses. Resultados: La determinación de ácido fenólico y ácido ascórbico del EG, mostró un alto contenido de antioxidantes (3323.0±23.3 mg de GAE/100g bs y 2508.0±143.8 mg de AAE/100g bs, respectivamente), al igual que actividad antioxidante determinada por ABTS•+ y DPPH• (17500.0±888.1 μmol TE/100g bs y 27804.0±94.0 μmol TE/100g bs, respectivamente). Por otro lado, la dieta alta en grasa produjo un incremento en la peroxidación lipídica en hígado y cerebro (3.40±1.05 y 3.99±1.49 nmol MDA/ml, respectivamente). El enriquecimiento de esta dieta con EG, redujo los niveles del daño a los lípidos tanto en el hígado y como el corazón (1.94±0.67 y 2.16±1.21 nmol MDA/ml, respectivamente). Mientras que el cerebro se mantuvo con altos niveles de peroxidación lipídica. Conclusión: Los resultados muestran que el extracto de guayaba tiene una acción de protección selectiva contra el daño oxidativo y su uso como un efecto potencial para prevenir el desarrollo de enfermedades no transmisibles asociadas con la obesidad.

La práctica deportiva exige mayor demanda nutricia para la función muscular pero también se requiere de favorecer la respuesta neurológica para lograr mejor rendimiento, coordinación, resultados y disminuir latiga. Una sobreexcitación de compuestos químicos que estimulen al Sistema Nervioso Central puede lograrse por medio de ayudas ergogénicas como la cafeína. Objetivo: Analizar la efectividad de la cafeína como ayuda ergogénica en deportistas para su uso competitivo, mediante la investigación en motores de búsqueda científicos. Metodología: Búsqueda de artículos científicos de publicación reciente, sobre ensayos clínicos de suplementación con cafeína en deportistas, por medio de motores de búsqueda especializados empleando la herramienta “MeSH. Resultados: El uso de cafeína en el deporte genera un impacto positivo en el rendiemiento, mejorando la fuerza y potencia del atleta y con ellos mejores resultados en la competición, retasa la aparición de fatiga y la disificación recomendada es de 3-6 mg/kg/día . Conclusión: La caféina como ayuda ergogénica mejora el rendimiento deportivo, el abuso de cafeína procuce efectos negativos en el rendimiento y puede causar toxicidad.

La fibra dietética es un componente de la dieta ampliamente estudiado, debido a que se le atribuyen una gran variedad de beneficios en la salud del consumidor. Existen diversas definiciones y clasificaciones para la fibra dietética, esta diversidad se genera por las distintas áreas que la que se estudian, una de las clasificaciones más aceptadas se basa en el grado de hidratación con agua, teniendo fibras solubles e insolubles. Sus efectos funcionales pueden ser tecnológicos o nutracéuticos, los primeros son las propiedades que otorga a un alimento, y los segundos los beneficios que genera en la salud. La fibra dietética puede encontrarse de forma natural en los alimentos o puede ser añadida en su elaboración. Es necesario tener un consumo adecuado de fibra dietética para poder disponer de todos los beneficios que brinda, desde sus efectos en la salud digestiva, hasta su papel en la prevención y tratamiento de diversas patologías.

El fútbol es unn juego de equipo muy popular mundialmente, considerado como un deporte intermitente debido a los movimientos intensos de corta duración con alta demanda energétiva, causante de fatiga y disminución del rendimiento durante el juego y entrenamientos. Objetivo: Analizar investigaciones actuales sobre los efectos de la ingesta de suplementos con PT e HCO sobre el rendimiento en futbolistas e identificar aquellos que tuvieron un mayor impacto. Método: Se realizó una revisión sistemática en la red con base a artículos publicados en PubMed, Scielo, Redalyc, Elsevier y Dialnet utilizando palabras claves como “football”, “supplementation”, “carbohydrates”, “protein”, “physical performance”, “ergogenic” y “recovery”. Resultados: Se encontraron en un inicio 33 estudios que realizaron intervenciones en futbolistas con suplementos de HCO y PT, de los cuales solo 11 mostraron tener algún impacto significativo sobre las pruebas físicas y marcadores bioquímicos. Conclusión: Las intervenciones que tuvieron un mayor impacto en el rendimiento y recuperación de los futbolistas utilizaron SN compuestos de HCO y PT en conjunto. La suplementación deportiva debe ser individualizada y es importante el acompañamiento de un profesional en nutrición que asesore sobre el consumo de SN que maximicen los beneficios.

Los jugos de frutos y hortalizas fermentados con Bacterias Ácido Lácticas (BAL) son productos que por los cambios estructurales ocasionados durante el proceso de fermentación han ganado relevancia dentro de los alimentos funcionales, además de las características nutricionales propias del fruto como los antioxidantes, que además de coadyuvar en el tratamiento de enfermedades no transmisibles que se caracterizan por el estrés oxidativo presentan propiedades antimicrobianas. Las BAL son microorganismos que al consumirlos ayudan sobre la colonización intestinal promoviendo equilibrio, tiene efectos asociados a la inmunidad, coadyuvan en distintas enfermedades no transmisibles. Otra aplicación relevante de los jugos fermentados es la síntesis de compuestos antimicrobianos como las bacteriocinas, que extiende la posibilidad de utilizar estos productos en el área farmacéutica, se conoce que tienen efectividad contra microorganismos patógenos resistentes. Con el consumo de estos productos se quiere promover el aporte adecuado de antioxidante, lograr un equilibrio en la microbiota y al mismo tiempo disminuir las resistencias microbiológicas a los fármacos.

Amaranth has been of interest for its nutritional quality and its multiple benefits; however, there is little research on its toxicological effect. This work studied antinutritional compounds, the cytotoxic and genotoxic effect in the Amaranthus protein extract (PEAh). The content of lectins, tannins, saponins, and trypsin inhibitors was determined. Biological studies were conducted to determine toxicity in male CD-1 mice by intraperitoneal administration. The genotoxic potential was determined by the micronucleus test. The bone marrow cytotoxicity was determined by polychromatic erythrocyte (PE) rate and the cytotoxic effect was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test. Our results showed considerably high concentrations of lectins and trypsin inhibitors, lower concentrations of tannins and saponins in PEAh. The PEAh was toxic to mice, presenting genotoxic and cytotoxic damage to bone marrow and hepatocytes.

Functional beverages market requires conservation methods where bioactive compounds could persist for their bioavailability. The aim of this work was determined the extractwion yield, antioxidant capacity and bioavailability of a cactus pear (Opuntia ficus-indica) juice blended using different solvent to extraction after pasteurization (PAST) or thermoultrasonication (TUS) treatment. The best properties were exhibited by TUS juice, showing 575.8 ± 11.1 mg GAE·L-1 for total phenolic, and 392.78 ± 4.1 mg betanain E·L-1 for pigment content. Which resulted in a greater antioxidant activity bioavailable (87% DPPH; 38% ABTS). The highest antioxidant activity was found in the TUS methanolic extraction, exhibiting higher bioaccessibility than the juice (78% ABTS; 179% DPPH). It can be concluded that thermoultrasonication and methanolic extraction of a cactus pear juice blend allows a greater antioxidant compounds to be bioavailable

The growing interest of consumers to find products with greater health benefits has led to multiple research works focused on product developments with antioxidant-rich foods by creating safe, acceptable, and high-value nutrition, even in those foods susceptible to deterioration, in order to replace synthetic preservatives with natural ones. Bee products are an alternative addition for food products (dairy and meat products, coating fruits, and alcoholic and non-alcoholic drinks), which can improve the final quality of the food for the benefit of the consumer. The aim of this review was to provide detailed information on the main findings of innovative food products based on the addition of bee products by highlighting their physicochemical and functional properties and their behavior throughout storage.

El jamón de pavo es uno de los embutidos más populares de origen cárnico y se encuentra regulado por Normas Oficiales Mexicanas en términos sanitario y comercial. El objetivo del presente estudio fue analizar 10 diferentes tipos de marcas comerciales de Jamón de Pavo mediante la recopilación de datos de macronutrientes, sodio, ingredientes añadidos y aditivos, en relación con los parámetros establecidos por las Normas Oficiales Mexicanas. Se concluyó que todos los productos de jamón de pavo analizados presentaron valores dentro de los rangos establecidos según las normas respecto a los valores nutrimentales, así como las características con relación a la calidad de envasado y etiquetado. Los productos tienen un alto contenido de sodio y aditivos por lo tanto su consumo debe ser moderado.

El betabel (Beta vulgaris L.) es un tubérculo que por su contenido en antioxidantes tiene propiedades preventivas de enfermedades como el cáncer, entre otras. Es consumido crudo, cocido, en ensaladas y jugos. El jugo de betabel, mantiene un alto contenido de antioxidantes, así como otros compuestos bioaccesibles que promueven la salud, pero que al ser sometido a pasteurización se generan pérdidas de estos. Actualmente existen tecnologías emergentes que brindan alternativas a las tecnologías convencionales como lo es el ultrasonido, que se ha demostrado que libera compuestos bioactivos y mantiene la inocuidad de los alimentos. Por lo anterior, el objetivo de este estudio fue evaluar las propiedades fisicoquímicas (pH, sólidos solubles totales, acidez titulable) y microbiológicas (recuento total y enterobacterias) del jugo de betabel termoultrasonicado con variables de amplitud (80 y 90%) y tiempo (10 y 15 min). El jugo termoultrasonicado tratado a 15min/90% presentó los valores más bajos en mesófilos aerobios y enterobacterias , proporcionando mayor inocuidad, con un elevado porcentaje de estabilidad sin alterar los sólidos solubles totales, acidez y viscosidad en el jugo.

El residuo de betabel ha llamado la atención entre la comunidad científica por su composición nutrimental, principalmente por sus antioxidantes, los cuales son importantes en la dieta de las personas ya que estos disminuyen el daño celular generado por los radicales libres que se generan normalmente en el metabolismo y durante el estrés oxidativo de enfermedades no transmisibles; sin embargo este residuo no es consumido ni comercializado. Por estas razones se desarrollan algunos métodos para la extracción de compuestos sin el uso de solventes como lo es el ultrasonido (US), siendo una alternativa para la extracción de compuestos conservando sus características naturales. El objetivo de este estudio fue extraer los antioxidantes del residuo de betabel (Beta Vulgaris) utilizando tecnología convencional y emergente. Se obtuvo un extracto acuoso, etanólico, macerado y por US. Los resultados mostraron que en compuestos fenólicos totales (CFT), la extracción por US obtuvo mayor cantidad de estos compuestos (534.64 EAG/100g bs) con respecto al control. Sin embargo, la mayor extracción de betaninas y betaxantinas fue con agua (1009.01 y 764.18 mg EB/100g bs). El ultrasonido es una tecnología emergente que podría ser utilizado para la extracción de compuestos antioxidantes provenientes de residuos del procesamiento de los alimentos reduciendo el consumo de energía, mejorando la vida útil y la calidad del producto.

In rural areas of the State of Hidalgo, Mexico, the maguey red worm or chinicuil (Comadia redtenbacheri Hamm.) and the maguey white worm (Aegiale hesperiaris Walk) are generally consumed dehydrated, while in urban areas they are eaten fried with butter. However, although their organoleptic characteristics improve, the effect on nutritional properties is unknown. Therefore, the objective of this study was to compare the proximal chemical composition and quality of fatty acids in butter-fried worms that are commercially available. In order to measure the oils quality, a chemical analysis and an instrumental analysis were performed. Lipids were predominant in dehydrated (40.11-44.67%) and fried (47.67-56.83%) samples. Moisture and temperature were the variables that increased the degradation of lipids in the samples. In the dehydrated and fried samples there were differences in the percentages of saturated and unsaturated fatty acids with 72.82-76.81% and 15.17-16.07% and 27.18-23.19% and 84.82-83.93%, respectively. Since the lipid material used to fry the worms was reused and is oxidized, so a control of the heat treatment or changing the cooking method is suggested.

Recently, industry has been focusing on the development of new products made from food by-products in order to reduce and take advantage of food wastes. The objective of this study was to evaluate tablet formulations developed by mixing two commercial excipients, microcrystalline cellulose (M) and &alpha, lactose-monohydrate (L), added with powder from residues (mesocarp and pericarp) of green and red (G and R) cactus pear fruit (Opuntia ficus-indica L. Mill), having the following formulations: green with microcrystalline cellulose (GM), green with lactose (GL), red with microcrystalline cellulose (RM), and red with lactose (RL). The results showed lower disintegration times for the tablets with microcrystalline cellulose. The fiber functional properties presented good values for lipid and water holding capacity. There was a higher total phenolic content (TPC) in formulations with green cactus pear residue powder with microcrystalline cellulose and lactose (GM and GL, respectively), but the DPPH and ferric reducing/antioxidant power (FRAP) values were higher in the formulations with red cactus pear residues (RM and RL), while ABTS values were similar among all formulations. In conclusion, tablets made from Opuntia residues are proposed as a product of interest for the food supplement industry because of the good quality parameters and the functional and antioxidant properties that they provide.

The purpose of this research was to obtain optimal thermosonication (TS) processing conditions of beetroot juice by using response surface methodology and its comparison with two thermal treatments at 70 °C for 20 min (TT1) and 80 °C for 10 min (TT2). Optimal TS processing conditions were amplitude of 80% and 10.5 min. Treated beetroot juice by TS had a greater inactivation in microbiological load and enzymatic activity in comparison to treated juices by thermal treatment (TT). Higher betanin content, antioxidant activity by ABTS and chelating activity were found in treated beetroot juice by TS than TT ones. After in vitro digestion processing, juice by TS presented higher betalains content than TT1, similar TPC and high chelating activity in comparison with both juice by TT and similar antioxidant activity by ABTS with TT1. These results suggest that TS processing can replace the thermal treatment in beetroot juice, maintaining their antioxidant properties as well as providing better in vitro digestion.

Background: Exercise training induces adaptive physiological and morphological modifications in the entire organism, however, excessive loads of training may increase damage in tissues. The purpose of this study was to evaluate the effect of silymarin in lung and liver histological changes in rats subjected to exercise training (ET). Methods: Male Wistar rats were subjected to an 8-week ET treadmill program 5 days per week, 60 min/session, and were previously administered 100 mg ascorbic acid or 100 mg of silymarin. Results: Silymarin increased alveolar and bronchial muscle size, improve vascularization, and reduced tissue inflammation. In liver, silymarin promoted the reduction of lipid content. Conclusion: Silymarin supplementation may improve inflammation in pulmonary tissue after 8 weeks of the ET treadmill program, improve cell recovery, and reduce intrahepatic lipid content.

The aim of this study was to investigate the effectiveness of ultrasound as a conservation method for the inactivation of Escherichia coli inoculated into cactus pear juices (green and purple). Total soluble solids, pH, titratable acidity, and the kinetics of E. coli in cactus pear juices treated by ultrasound (60%, 70%, 80% and 90% amplitude levels for 1, 3 and 5 min) were evaluated over 5 days. Total inactivation was observed in both fruit juices after 5 min of ultrasound treatment at most amplitude levels (with the exception of 60% and 80%). After one and two days of storage, the recovery of bacteria counts was observed in all cactus pear juices. Ultrasound treatment at 90% amplitude for 5 min resulted in non-detectable levels of E. coli in cactus pear juice for 2 days. The parameters of pH, titratable acidity and soluble solids were unaffected.

Silymarin (SM) is a mixture of flavolignans extracted from the seeds of species derived from Silybum marianum, commonly known as milk thistle or St. Mary’sthistle. These species have been widely used in the treatment of liver disorders in traditional medicine since ancient times. Several properties had been attributed to the major SM flavolignans components, identified as silybin, isosilybin, silychristin, isosilychristin, and silydianin. Previous research reported antioxidant and protective activities, which are probably related to the activation of the nuclear factor erythroid 2 (NFE2)-related factor 2 (Nrf2), known as a master regulator of the cytoprotector response. Nrf2 is a redox-sensitive nuclear transcription factor able to induce the downstream-associated genes. The disruption of Nrf2 signaling has been associated with different pathological conditions. Some identified phytochemicals from SM had shown to participate in the Nrf2 signaling pathway; in particular, they have been suggested as activators that disrupt interactions in the Keap1-Nrf2 system, but also as antioxidants or with additional actions regarding Nrf2 regulation. Thus, the study of these molecules makes them appear attractive as novel targets for the treatment or prevention of several diseases.

Roselle (Hibiscus sabdariffa L.), also known as jamaica in Spanish, is a perennial plant that grows in tropical and subtropical regions, including China, Egypt, Indonesia, Mexico, Nigeria, Thailand, and Saudi Arabia. It has a long history of uses, mainly focused on culinary, botanical, floral, cosmetic, and medicinal uses. The latter being of great impact due to the diuretic, choleretic, analgesic, antitussive, antihypertensive, antimicrobial, immunomodulatory, hepatoprotective, antioxidant, and anti-cancer effects. These therapeutic properties have been attributed to the bioactive compounds of the plant, mainly phenolic acids, flavonoids, anthocyanins, and organic acids (citric, hydroxycitric, hibiscus, tartaric, malic, and ascorbic). Most literature reviews and meta-analyses on the therapeutic potential of Hibiscus sabdariffa L. (Hs) compounds have not adequately addressed the contributions of its organic acids present in the Hs extracts. This review compiles information from published research (in vitro, in vivo, and clinical studies) on demonstrated pharmacological properties of organic acids found in Hs. The intent is to encourage and aid researchers to expand their studies on the pharmacologic and therapeutic effects of Hs to include assessments of the organic acid components.

The objective of this study was to evaluate changes in color, betalain content, browning index, viscosity, physical stability, microbiological growth, antioxidant content and antioxidant activity of purple cactus pear juice during storage after thermoultrasonication at 80% amplitude level for 15 and 25 min in comparison with pasteurized juice. Thermoultrasound treatment for 25 min increased color stability and viscosity compared to treatment for 15 min (6.83 and 6.72 MPa, respectively), but this last parameter was significantly lower (p

The purpose of the present study was to determine the optimal ultrasound conditions (amplitude level and time) for the extraction of cactus pear seed oil with the highest antioxidant activity using a closed system. Seed oil was analyzed for yield, antioxidant activity by ABTS and DPPH, and antimicrobial activity. Conventional extraction methods were assessed for comparison. Amplitude level significantly affected antioxidant activity in linear terms (p< 0.0001 DPPH andp< 0.001 ABTS, resp.) so, at lower amplitudes, the higher antioxidant activity was achieved. The optimum ultrasound extraction conditions were of 78% amplitude for 10 min and yielded antioxidant activity values of 66.25 mg AAE/100 g and 289 µmol TE/100 g for ABTS and DPPH, respectively. Compared with conventional extraction methods, ultrasound exhibited lower oil yield and antioxidant activity but had the potential to achieve comparable results if multiple ultrasound extractions are performed in the time needed by conventional methods. Seed oils showed similar antimicrobial activity despite the extraction method and were more effective againstEscherichia coli. The results demonstrated that ultrasound can be an alternative extraction method of seed oils from fruits such as cactus pear.

Pozol is a traditional fermented maize dough prepared in southeastern Mexico. Wide varieties of microorganisms have already been isolated from this spontaneously fermented product; and include fungi, yeasts, and lactic- and non-lactic acid bacteria. Pozol presents physicochemical features different from that of other food fermentation products, such as a high starch content, in addition to a low protein content. It is these qualities that make it intractable for protein recovery and characterization. The aim of this study was to develop a methodology to optimize the recovery of proteins from the pozol dough following fermentation, by reducing the complexity of the mixture prior to 2D-PAGE analysis and sequencing, to allow the characterization of the metaproteome of the dough. The proteome of 15 day fermented maize dough was characterized; proteins were separated and analyzed by mass spectrometry (LC–MS/MS). Subsequent sequence homology database searching, identified numerous bacterial and fungi proteins; with a predominance of lactic acid bacterial proteins, mainly from the Lactobacillus genus. Fungi are mainly represented by Aspergillus. For dominant genera, the most prevalent proteins belong to carbohydrate metabolism and energy production, which suggest that at 15 days of fermentation not only fungi but also bacteria are metabolically active. Biological significance Several methodologies have been employed to study pozol, with a specific focus toward the identification of the microbiota of this fermented maize dough, using both traditional cultivation techniques and culture independent molecular techniques. However to date, the dynamics of this complex fermentation is not well understood. With the purpose to gain further insight into the nature of the fermentation, we used proteomic technologies to identify the origin of proteins and enzymes that facilitate substrate utilization and ultimately the development of the microbiota and fermentation. In this paper we overcome the first general challenge for such studies, obtaining a protein sample with adequate quality capable of representing the system. This article is part of a Special Issue entitled: Proteomics, mass spectrometry and peptidomics, Cancun 2013. Guest Editors: Cesar Lopez-Camarillo, Victoria Pando-Robles and Bronwyn Jane Barkla.

For many years, several studies have been employing lectin from vegetables in order to prove its toxic effect on various cell lines. In this work, we analyzed the cytotoxic, antiproliferative, and post-incubatory effect of pure tepary bean lectins on four lines of malignant cells: C33-A; MCF-7; SKNSH, and SW480. The tests were carried out employing MTT and 3[H]-thymidine assays. The results showed that after 24 h of lectin exposure, the cells lines showed a dose-dependent cytotoxic effect, the effect being higher on MCF-7, while C33-A showed the highest resistance. Cell proliferation studies showed that the toxic effect induced by lectins is higher even when lectins are removed, and in fact, the inhibition of proliferation continues after 48 h. Due to the use of two techniques to analyze the cytotoxic and antiproliferative effect, differences were observed in the results, which can be explained by the fact that one technique is based on metabolic reactions, while the other is based on the 3[H]-thymidine incorporated in DNA by cells under division. These results allow concluding that lectins exert a cytotoxic effect after 24 h of exposure, exhibiting a dose-dependent effect. In some cases, the cytotoxic effect is higher even when the lectins are eliminated, however, in other cases, the cells showed a proliferative effect.

Cactus pear (Opuntia ficus-indica) fruit is a berry with a tasty pulp full of seeds that constitutes about 10–15% of the edible pulp. In Mexico, cactus pear is mainly consumed fresh, but also has the potential to be processed in other products such as juice. The objective of this study was to eval uate the effect of different ultrasound conditions at amplitude levels ranging (40% and 60% for 10, 15, 25 min; 80% for 3, 5, 8, 10, 15 and 25 min) on the characteristics of purple cactus pear juice. The evaluated parameters were related with the quality (stability, Brix, pH), microbial growth, total phenolic compounds, ascorbic acid and antioxidant activity (ABTS, DPPH and % chelating activity) of purple cactus pear juices. The ultrasound treatment for time period of 15 and 25 min significantly reduced the microbial count in 15 and 25 min, without affecting the juice quality and its antioxidant properties. Juice treated at 80% of amplitude level showed an increased of antioxidant compounds. Our results demon strated that sonication is a suitable technique for cactus pear processing. This technology allows the achievement of juice safety and quality standards without comp romising the retention of antioxidant compounds.

Summary Undernutrition induces an increase of the oxidative stress that can predispose offspring to various diseases in adulthood through epigenetic reprogramming. The aim of this study was to evaluate the effects of intergenerational undernutrition on protein oxidation and antioxidant defence response on liver, heart and brain of the second-generation neonates (F2) of undernourished rats. For this purpose, both parents in parental (F0) and first generation (F1) were fed with a low-nutrient diet. Body mass and length decreased (p 0.05) while catalase activity increased only in brain (p

In Mexico, the consumption of green cactus pear fruit it is usually eaten fresh. This fruit could be a natural product with a rapid presence in the market, especially if the production technologies are optimized. The aim of the present study was to evaluate the effect of ultrasound (amplitudes 40, 60 and 80% at different times 10, 15 and 25 min) in the quality (pH, °Brix, stability), microbial growth, phenolic content, ascorbic acid and the antioxidant activity of green cactus pear juice. We found that application of a greater amplitude and time of ultrasound (higher 60% 15 min) significantly decreased the microbial load. Treatment >15 min presented higher total solid soluble (°Brix) with values of 13.00 - 13.40 °Brix. Treatment 60% 15 min, 80% 8, 15 and 25 min showed better physical stability (lower % settled solids) around 16.93%-19.41%. Appreciable amount of bioactive compounds was found mainly in treatment at 80% 25 min in total phenolic contents, while ascorbic acid was the treatments at 60% 25 min and 80% 10 min, preserving the antioxidant activity present in the juice mainly treatments >15 min in ABTS. The amplitude and time of ultrasound applied in the juice might allow the suitable conditions of conservation for industrial use.

Radicales libres, estrés oxidativo, antioxidantes, enfermedades degenerativas, terapia antioxidante

The natural living style of Escherichia coli occurs in the gastrointestinal tract, where most of its existence is spent under anaerobic conditions and in stationary phase of growth. Here we report on the heat shock response of E. coli K-12 cells growing in the presence or absence of oxygen. An rpoH mutant (impaired in the synthesis of the sigma(32) transcriptional factor) exhibited an increased sensitivity to heat shock but only in the exponential phase of aerobic growth, suggesting that in anaerobic growth conditions, and in aerobic stationary phase, sigma(32)-independent mechanisms are playing a prime role in protecting cells from heat stress. Our results demonstrated that sigma(S) is not involved in this protection system. Studies on the kinetics of synthesis of Heat shock proteins (Hsp) after an abrupt rise in temperature demonstrated that in the absence of oxygen, the synthesis of Hsp is triggered faster and is sustained for a longer period of time compared to aerobic growth conditions. Finally, the heated cells in the exponential phase of aerobic growth displayed a high concentration of oxidatively damaged proteins in the presence of 4 mM H(2)O(2), in sharp contrast to cultures of stationary phase or anaerobic growth.

The expression of minigenes in bacteria inhibits protein synthesis and cell growth. Presumably, the translating ribosomes, harboring the peptides as peptidyl-tRNAs, pause at the last sense codon of the minigene directed mRNAs. Eventually, the peptidyl-tRNAs drop off and, under limiting activity of peptidyl-tRNA hydrolase, accumulate in the cells reducing the concentration of specific aminoacylable tRNA. Therefore, the extent of inhibition is associated with the rate of starvation for a specific tRNA. Here, we used minigenes harboring various last sense codons that sequester specific tRNAs with different efficiency, to inhibit the translation of reporter genes containing, or not, these codons. A prompt inhibition of the protein synthesis directed by genes containing the codons starved for their cognate tRNA (hungry codons) was observed. However, a non-specific in vitro inhibition of protein synthesis, irrespective of the codon composition of the gene, was also evident. The degree of inhibition correlated directly with the number of hungry codons in the gene. Furthermore, a tRNA(Arg4)-sequestering minigene promoted the production of an incomplete beta-galactosidase polypeptide interrupted, during bacterial polypeptide chain elongation at sites where AGA codons were inserted in the lacZ gene suggesting ribosome pausing at the hungry codons.