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1.
Plant Dis ; 99(11): 1590-1595, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30695957

RESUMEN

Anthracnose, caused by Colletotrichum truncatum (syn. C. capsici), has become a common disease of tropical crops, severely affecting the quantity and quality of fruit and seed and, therefore, reducing their market value. For years, chemical control has been extensively used for managing this disease. However, the appearance of isolates that are resistant to the most commonly employed fungicides is increasingly widespread. Twenty C. truncatum isolates from pepper, papaya, and physic nut were tested in vitro against four fungicides to determine their sensitivity. All evaluated isolates were resistant to azoxystrobin and thiabendazole and susceptible to cyprodinil + fludioxonil and mancozeb. To determine the molecular mechanism conferring thiabendazole resistance, the TUB-2 gene was characterized, revealing a glutamic acid to alanine substitution at position 198 in 6 of the 20 isolates that were tested. This work confirms the emergence of benzimidazole-based fungicide resistance in C. truncatum populations and highlights the need for monitoring fungicide sensitivity as an essential activity for the development of effective control schemes.

2.
Heliyon ; 6(3): e03632, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32258479

RESUMEN

The growing interest in bioactive compounds, especially in polyphenols, is due to their abundance in the human diet and potentially positive effects on health. The consumption of polyphenols has been shown to possess anti-diabetic properties by preventing insulin resistance or insulin secretion through different signaling pathways, this effect is associated with their capacity to exert genomic modulations. Several studies have suggested that polyphenols could also bind to cellular proteins and modulate their activity, however, the mechanisms of action underlying their beneficial effects are complex and are not fully understood. The aim of this work was to characterize phenolic compounds present in blue corn and black bean extracts as well as identify their potential interactions with target proteins involved in diabetes pathogenesis using in silico approach. Total polyphenols content of both blue corn and black beans was identified using UPLC-ESI/qTOF/MS and quantified by colorimetric assays. In this work we identified twenty-eight phenolic compounds in the extracts, mainly anthocyanins, flavonols, hydroxycinamic acids, dihydroxybenzoic acids, flavones, isoflavones, and flavanols. Interactome of these compounds with thirteen target proteins involved in type 2 diabetes mellitus was performed in-silico. In total, 312 bioactive compounds/protein interaction analyses were acquired. Molecular docking results highlighted that nine of the top ten interactions correspond to anthocyanins, cyanidin 3-glucoside with 11ß-HS, GFAT, PPARG; delphinidin 3-glucoside with 11ß-HS, GFAT, PTP and RTKs; and petunidin 3-glucoside with 11ß-HS and PTP. These proteins are involved in mechanisms regulating functions such as inflammation, insulin resistance, oxidative stress, glucose and lipid metabolism. In conclusion, this work provides a prediction of the potential molecular mechanism of black bean and blue corn polyphenols, specifically anthocyanins and could constitute new pathways by which compounds exert their antidiabetic benefits.

3.
Lipids ; 34(6): 639-42, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10405979

RESUMEN

One of the few sources of long-chain n-3 polyunsaturated fatty acids is fish oil, but considerable variation may exist according to species and season. In this study, the fatty acid profiles of sardine oils from Sardinops sagax caeruleus of the Gulf of California, Mexico, were evaluated in three seasonal catch periods. Oil quality was also evaluated by peroxide and free acid values. The most abundant fatty acids found in the oils were palmitic acid (19.3%), oleic acid (14.3%), eicosapentaenoic acid (EPA, 20.4%), and docosahexaenoic acid (DHA, 12.2%). There was no significant difference in the composition and quality among the six reduction plants where the samples were obtained. However, a significant difference in the proportion of EPA and DHA in one of the catch seasons analyzed was observed.


Asunto(s)
Ácidos Grasos/análisis , Aceites de Pescado/química , Estaciones del Año , Cromatografía de Gases , Aceites de Pescado/normas , Control de Calidad
4.
Vet Rec ; 130(3): 45-8, 1992 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-1546434

RESUMEN

The efficacy of amoxycillin in the control of laboratory induced Aeromonas salmonicida infection in Atlantic salmon parr was investigated. When given in the diet at a dose rate of 80 mg per kg bodyweight it was effective against both a moderate and severe challenge (with mortality rates in untreated groups of 75 per cent and 45 per cent). At 40 mg per kg it was effective against the moderate challenge only. The plasma levels in these regimens were 1.25 micrograms per ml and 0.3 to 0.6 micrograms per ml and the minimum inhibitory concentration of the challenge strain of A salmonicida was 0.6 micrograms per ml. The potential of the Charm radiobioassay system in detecting antibiotic residues in fish tissue was studied. The level of amoxycillin in muscle and bone from fish in mid-treatment at 80 mg per kg was 0.32 micrograms per ml. After a 12 day withdrawal period at 18 degrees C no residue was detected within the 0.005 micrograms per ml limit of this test.


Asunto(s)
Aeromonas , Amoxicilina/uso terapéutico , Enfermedades de los Peces/prevención & control , Infecciones por Bacterias Gramnegativas/veterinaria , Salmón , Amoxicilina/administración & dosificación , Amoxicilina/farmacocinética , Animales , Bacteriemia/prevención & control , Bacteriemia/veterinaria , Huesos/metabolismo , Residuos de Medicamentos/análisis , Infecciones por Bacterias Gramnegativas/prevención & control , Intubación Gastrointestinal/veterinaria , Músculos/metabolismo , Distribución Tisular
5.
Arch Latinoam Nutr ; 45(2): 122-7, 1995 Jun.
Artículo en Español | MEDLINE | ID: mdl-8729263

RESUMEN

Three treatments with chemical preservative (sodium propionate, potassium sorbate-methylparaben and hydrogen peroxidemethyl paraben) were tested to delay microbial spoilage and extend shelf-life of corn tortillas at room temperature (25 degrees C). The treatment with the best results was selected for further studies using two types of packaging: Paper and high density polyethylene. Quality of corn tortillas during storage was assessed by measuring water content, microbial analysis (Total Plate Count, molds and yeast) and throguh sensory evaluation. Results were analyzed by covariance analysis and slope contrast between packaging materials at p<0.05. Spoilage of tortilla without preservative occurred within 24 hours due to a large number of gram negative bacteria, molds and yeasts, which were responsible for offensive odors. Only the combination of hydrogen peroxide-methyl paraben had a significant effect on retarding bacterial yeast spoilage. In addition, hydrogen peroxide residues could not [correction of no] be chemically detected after 2 days of storage. Results from this study show that tortilla can be kept for up to six days at room temperature with acceptable sensory properties with proper preservative treatment and packaging.


Asunto(s)
Manipulación de Alimentos , Conservación de Alimentos/métodos , Zea mays/microbiología , Análisis de Varianza , Humedad , Peróxido de Hidrógeno/farmacología , Parabenos/farmacología , Muestreo , Temperatura , Factores de Tiempo
6.
Arch Latinoam Nutr ; 41(4): 584-94, 1991 Dec.
Artículo en Español | MEDLINE | ID: mdl-1841539

RESUMEN

Three packaging materials (tortilla-packing paper, low-density polyethylene and high density polyethylene) were used to evaluate tortilla shelf-life at two different temperatures (-10 degrees C and 5 degrees C). Tortilla quality changes upon storage were evaluated by measuring pH, total moisture, texture (puncture and cutting resistance) and sensory characteristics. Results were analyzed by means of covariance analysis and slope contrast between treatments with a 0.05 level of significance. At -10 degrees C, the quality of tortillas did not change significantly during 11 days of storage, and the influence of the packaging material was negligible. Tortilla kept at 5 degrees C in high or low-density polyethylenes, had significantly better quality than the paper-packaged product. Textural changes were best shown by the Instron puncture resistance test than by the cutting resistance test. At 5 degrees C, packaged tortillas had a microbiologically stable level for up to seven days, while that at -10 degrees C significantly improved over the storage period.


Asunto(s)
Manipulación de Alimentos , Conservación de Alimentos , Análisis de Varianza , Contaminación de Alimentos/prevención & control , Microbiología de Alimentos , Congelación , Papel , Polietilenos , Factores de Tiempo , Zea mays
7.
Arch Latinoam Nutr ; 48(1): 58-61, 1998 Mar.
Artículo en Español | MEDLINE | ID: mdl-9754407

RESUMEN

Shrimp shell waste obtained from several industrial freezing-purchasing plants of Guaymas, Sonora, Méx., was studied as a source of value-added chitin biopolymers. In part I, the effect of different isolation conditions on the chitin yield and chemical characteristic, was investigated. Protein and mineral matter were removed with alkali and acid treatment respectively. A 2x2x3 factorial a way of a completely randomized design was used in order to evaluate the effect of the process variables, namely, NaOH concentration (0.4 and 2%) during the deproteinization and HCl concentration (3 and 5%) carried out at 40, 50 and 60 degrees C. The best processing conditions were desproteinization with 2% NaOH, and demineralization with 5% HCl at 50 degrees C, in terms of final ash and chitin content and yield. In part II, a selection of methods of isolation of chitin and chitosan was studied in order to establish the best conditions for scaling up a process to pilot plant level. The processing conditions were selected from reported methods as well as from those defined in part I. Purity of chitin samples was determined in terms of residual protein, ash and chitin each one to produce high quality chitin (0.00% protein, 0.01% ash, 99.99% chitin) and standard grade chitin (0.00% protein, 0.09% ash, 99.13% chitin). Both products were considered as of adequate quality and their manufacture process could be scaled up by further optimization of the processing conditions.


Asunto(s)
Quitina/aislamiento & purificación , Decápodos/química , Análisis de Varianza , Animales , Biopolímeros/aislamiento & purificación , México
8.
Rev. mex. ing. bioméd ; 40(1): e201808EE1, Jan.-Apr. 2019.
Artículo en Español | LILACS | ID: biblio-1043136

RESUMEN

Resumen La biología sintética (SynBio) es una disciplina de reciente aparición que sirve para diseñar o re-diseñar sistemas biológicos y otorgarles cualidades mejoradas o nuevas cualidades. En la SynBio el diseño de nuevos sistemas biológicos requiere de herramientas moleculares muy precisas, tales como: a) la bioinformática, b) la secuenciación NGS (Next Generation Sequencing), el ensamble y/o síntesis de ADN c) y la edición de genomas a través de CRISPR-Cas9. En la SynBio encontramos además otras disciplinas con un perfil más hacia el ámbito social, las cuales tocan aspectos éticos, legales, filosóficos y económicos, considerándose así una multidisciplina. La SynBio está propiciando el desarrollo de nuevas tecnologías (emergentes) partiendo de una óptica ingenieril. En la SynBio, al ADN se le entiende de forma práctica y abstracta como una serie de partes que se pueden ensamblar en cierto orden para obtener los productos deseados una vez que se conoce la funcionalidad de cada parte. La SynBio ha dado pie a una nueva concepción de la economía a nivel mundial y por consecuencia se ha tomado muy seriamente el termino Bioeconomía como una nueva disciplina que transformará a las sociedades.


Abstract Synthetic biology (SynBio) it is considered a very recent discipline. View as a tool serves to design or re-design biological systems, giving them improved qualities or new qualities. In the SynBio, the design of new biological systems requires very precise molecular tools, such as: a) bioinformatics, b) sequencing NGS (Next Generation Sequencing), assembly and synthesis of DNA c) and CRISPR- Cas9 genome editing. Within the SynBio there are other social profile disciplines which concerned to ethical, legal, philosophical, and economic, and for that reason it is considered a multidiscipline. The SynBio is promoting the development of new (emerging) technologies based on an engineering perspective. In SynBio, DNA is understood in a practical and abstract way as a series of parts that can be assembled in a certain order to obtain the desired products once the functionality of each part is known. The SynBio has given rise to a new conception of the economy worldwide and consequently the term Bioeconomy is already taken very seriously as a new discipline that will transform societies.

9.
Colloids Surf B Biointerfaces ; 86(1): 242-6, 2011 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-21497069

RESUMEN

The aim of this work was to develop and characterize a new type of nanocapsules. To this end, a nanoemulsion bearing an oily core (Miglyol 812) was obtained by spontaneous emulsification and stabilized by dodecyl-trimethylammonium chloride (DTAC), a commercial cationic surfactant; this nanoemulsion was coated with proportionally very small amounts of κ-carrageenan (at molar charge ratios of Z ≤ 0.0045) that interact predominantly by an electrostatic mechanism with the positively charged sites at the polar heads of DTAC at the nanoemulsion's surface to harness nanocapsules of average size ~250-330 nm and zeta potential (ζ) ranging from ~+80 to +7 mV. The potential application of the new type of developed nanosystems as drug delivery vehicles has yet to be investigated and fully realized.


Asunto(s)
Carragenina/química , Nanocápsulas/química , Compuestos de Amonio Cuaternario/química
10.
Mol Biotechnol ; 49(1): 48-55, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21253896

RESUMEN

Colletotrichum capsici is an important fungal species that causes anthracnose in many genera of plants causing severe economic losses worldwide. A primer set was designed based on the sequences of the ribosomal internal transcribed spacer (ITS1 and ITS2) regions for use in a conventional PCR assay. The primer set (CcapF/CcapR) amplified a single product of 394 bp with DNA extracted from 20 Mexican isolates of C. capsici. The specificity of primers was confirmed by the absence of amplified product with DNA of four other Colletotrichum species and eleven different fungal genera. This primer set is capable of amplifying only C. capsici from different contaminated tissues or fungal structures, thereby facilitating rapid diagnoses as there is no need to isolate and cultivate the fungus in order to identify it. The sensitivity of detection with this PCR method was 10 pg of genomic DNA from the pathogen. This is the first report of a C. capsici-specific primer set. It allows rapid pathogen detection and provides growers with a powerful tool for a rational selection of fungicides to control anthracnose in different crops and in the post-harvest stage.


Asunto(s)
Colletotrichum/genética , Colletotrichum/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Secuencia de Bases , Carica/microbiología , Cartilla de ADN , ADN de Hongos/análisis , ADN de Hongos/genética , México , Técnicas de Diagnóstico Molecular , Datos de Secuencia Molecular , Enfermedades de las Plantas/microbiología , Sensibilidad y Especificidad , Análisis de Secuencia de ADN , Especificidad de la Especie
11.
Crit Rev Food Sci Nutr ; 46(2): 185-96, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16431409

RESUMEN

Astaxanthin is a carotenoid widely used in salmonid and crustacean aquaculture to provide the pink color characteristic of that species. This application has been well documented for over two decades and is currently the major market driver for the pigment. Additionally, astaxanthin also plays a key role as an intermediary in reproductive processes. Synthetic astaxanthin dominates the world market but recent interest in natural sources of the pigment has increased substantially. Common sources of natural astaxanthin are the green algae Haematococcus pluvialis, the red yeast, Phaffia rhodozyma, as well as crustacean byproducts. Astaxanthin possesses an unusual antioxidant activity which has caused a surge in the nutraceutical market for the encapsulated product. Also, health benefits such as cardiovascular disease prevention, immune system boosting, bioactivity against Helycobacter pylori, and cataract prevention, have been associated with astaxanthin consumption. Research on the health benefits of astaxanthin is very recent and has mostly been performed in vitro or at the pre-clinical level with humans. This paper reviews the current available evidence regarding astaxanthin chemistry and its potential beneficial effects in humans.


Asunto(s)
Animales , Antioxidantes/administración & dosificación , Acuicultura , Enfermedades Cardiovasculares/prevención & control , Crustáceos/metabolismo , Suplementos Dietéticos , Eucariontes/metabolismo , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/prevención & control , Helicobacter pylori , Humanos , Inmunidad/efectos de los fármacos , Estructura Molecular , Neoplasias/prevención & control , Xantófilas/administración & dosificación , Xantófilas/biosíntesis , Xantófilas/química , Levaduras/metabolismo
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