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El uso de enzimas como α-amilasas, xilanasas y glucosidasas es una buena alternativa para obtener una mayor eficiencia en los productos de la industria panificadora, sin dejar de mencionar la lacasa que ha mostrado un potencial prometedor. Así, el objetivo de este estudio fue obtener concentrados enzimáticos de xilanasas, amilasas, celulasas y lacasas a partir de cepas nativas de Pycnoporus sanguineus. Para lo cual, se evaluó el efecto del medio de cultivo sobre la producción de lacasa juntamente con el escrutinio en medio sólido para la detección de xilanasas, amilasas y celulasas. A los concentrados enzimáticos obtenidos se les determinaron las unidades de lacasa y carbohidrolasas. Los títulos más altos de lacasa se presentaron en el medio Tx2. Con respecto a las carbohidrolasas, se detectaron en diferentes niveles de actividad y combinaciones. El concentrado con altos niveles de amilasa y lacasa fue CH116, mientras que LE90 tuvo la mayor actividad de xilanasa y LE133 de celulasa. La cepa CH116 fue productora de amilasa, celulasa, xilanasa y lacasa, siendo la de mayor potencial en la industria panificadora, mientras que LE90 puede ser utilizada en la industria papelera por su combinación de xilanasas y lacasa.

Sweet sorghum Sorghum bicolor (L.) Moench) is a promising crop for bioethanol production characterized by its high biomass yield, sugar-rich stalks, facile juice extraction, and ability to adapt to different production systems. The objective of this study was to assess the effects of cultivation practices (soil treatments) on the juice, sugar, and ethanol yields of sweet sorghum variety Roger. Three methods of tillage (minimum, traditional, and traditional tillage with rupture of the plow layer) and three types of fertilizers (inorganic, organic, and without fertilizer) were assayed. The best results of stem yield (44.3 tons/ha), juice production (25.6 m3/ha), concentration of soluble solids in the juice (16.9 °Brix), and juice ethanol yield (2.1 m3/ha) were obtained under a mixture of traditional plowing with plow layer breaking, applying an organic fertilizer. In addition, the extracted juice allowed yeast (industrial Saccharomyces cerevisiae PE-2) growth and conversion to ethanol without the need for nutrients supplementation. Therefore, sweet sorghum continues to be an interesting bioenergetic crop for production of first-generation biofuels.

Tuberculosis drug resistance (DR) is a global problem that is not fully elucidated. Previously, overexpression of esxG and esxH genes was reported in a multidrug-resistant (MDR) Mycobacterium tuber...

The use of lignocellulosic wastes reduces dependence on fossil fuel resources, contributes to sustainable waste management, and reinforces the circular economy model of continual use of resources. Typically, the second generation of bioethanol production involves several steps to transform lignocellulosic material into bioethanol. The more complicated step of the overall process is to define a tailor-made to each lignocellulosic material available with a wide variety of complex structures of the lignin, hemicellulose, and cellulose. However, the thermochemicals are the most frequently reported pretreatments, and they have the bottleneck of producing an additional waste stream with a high charge of pollution owing to chemical products implicated. This problem harms on the zero waste policy that we must include in our technological process to be considered sustainable and ecological processes. Consolidated bioprocessing (CBP) is a viable alternative to produce bioethanol from lignocellulosic materials, using a single microorganism, in one-step, and no chemical products are implied. Three agro-industrial wastes with lignocellulosic characteristics were evaluated as a substrate for bioethanol production with a Mexican native white-rot fungus Trametes hirsuta CS5 in a one-step process. Qualitative and quantitative analyses of lignocellulolytic enzymes produced by native fungus were carried out. Instead, Trametes hirsuta is a lignin degrader white-rot fungus; it was capable to produce until 500 U/L of cellulase titers and a maximum xylanase activity of 45 U/mL when it was cultivated in orange peel substrate. Substantial ethanol yields were achieved using lignocellulosic materials like brewer’s spent grain (BSG), orange peel (OP), and wheat bran (WB) as a carbon source in fermentation with no chemicals, which represents a zero waste environment-friendly ethanol production system. Ethanol yield on wheat bran was the highest of all evaluated substrates, reaching value of 34.9% at 7 days, being T. hirsuta able to degrade other hexoses and pentoses present in the structural polymers of cellulose and hemicellulose.

The aim of this study was to identify a Mexican native basidiomycete strain with antagonistic potential against phytopathogenic fungi. The antifungal activity of fifteen isolates against Fusarium oxysporum, Fusarium solani, Colletotrichum truncatum, Colletotrichum coccodes, Colletotrichum sp., Stemphylium solani, Botrytis cinerea, Epicoccum nigrum, Phomopsis sp. and Alternaria solani was studied in vitro using dual culture assay. An isolate of Macrolepiota sp (CS185) exhibited the strongest ability to compete on potato dextrose agar medium (PDA) causing 22.2 up to 46.6% inhibition in seven out of ten pathogens evaluated. The addition of 30% Macrolepiota sp. liquid filtrates (from 7 day-cultures in potato dextrose broth) to PDA plates inhibited 66% of A. solani growth. Application of Macrolepiota sp. CS185 culture fluids to control early blight disease caused in tomato plants by A. solani under greenhouse conditions diminished disease incidence and percent of damage. The length of the stems, the roots and the foliar area increased in the treated plants and, above all, the foliar symptoms decreased by 73%. Sesquiterpene lactones and quinones identified in culture fluids might be responsible for Macrolepiota antifungal activity. This study proves that Macrolepiota sp. CS185 culture filtrates have potential in biocontrol of early blight disease.

En El Salvador, desde hace siete años, se ejecutan lineamientos y normativas para la atención a todas las formas de violencia. Objetivo. Identificar conocimientos, barreras y facilitadores del personal del área metropolitana de San Salvador que atiende víctimas de violencia para el cumplimiento de normativa y lineamiento vigente. Metodología. Diseño cualitativo de triangulación de datos recopilados en el área metropolitana de San Salvador, en las Unidades Comunitarias de Salud Familiar. Se aplicó una entrevista semiestructurada a 36 profesionales del Ministerio de Salud que atienden a personas violentadas. Resultados. El 69% del personal ha recibido capacitación en lineamientos y el 58% en normativa de atención a todas las formas de violencia. De 10 pasos para la atención se reconocen: consulta médica (94%), entrevista (92%), soporte emocional, intervención en crisis (89%), referencia, retorno e interconsulta (81%), evitar barreras culturales y religiosas (47%). El 39% del personal de salud identificó señales de alerta de violencia contra mujeres. El 56% no dio aviso por seguridad de la paciente. Barreras identificadas: capacitación y recursos materiales insuficientes, inadecuado espacio físico. Facilitadores identificados: capacitaciones, trabajo en equipo e idoneidad del personal. Conclusión. El conocimiento sobre lineamientos y normativas entre el recurso de salud, en general, es moderado. Principales factores para su ejecución son la presencia de personal capacitado y el trabajo en equipo. Las barreras son la falta capacitación en normativas, leyes y género, la falta de personal y saturación del trabajo, pocos recursos materiales para información y educación en prevención de violencia de género.

One primary drawback of enzyme catalysis at industrial scale is the short-term service life of the enzymes, they lose their activity due to oxidation or other processes which results in less stability and a shorter lifetime thereby rendering them less efficient. An effective way to increase the stability of the enzymes is to attach them to nanoparticles. In this work, the polymer Eudragit&reg, L 100-55 sensitive to pH was used to prepare laccase polymeric nanoparticles by the double-emulsion solvent evaporation approach. The size and morphology of the nanoparticles obtained were evaluated&mdash, as well as the encapsulation efficiency and zeta potential. pH effect on activity and stability was compared between free and immobilized laccase. Their stability was also determined in a sequential assay involving acidic pHs up to alkaline ones. The nanoparticles had a spherical shape with a mean size of 147 nm, zeta potential of &minus, 22.7 mV at pH 7.0 and load efficiency of 87%. The optimum pH of both free and immobilized laccases was 3.0, being the nanoparticles more stable at acidic pHs. Thus, this would be the first report of obtaining laccase nanoparticles with potential application in animal feed due to the stability conferred to enzymatic activity at pHs similar to those present in the gastrointestinal tract of rabbits, which would allow their potential use in animal feed.

One primary drawback of enzyme catalysis at industrial scale is the short term service life of the enzymes. Enzymes lose their activity due to oxidation or other processes which results in less stability and a shorter lifetime thereby rendering them less efficient. An effective way to increase the stability, longevity and reusability of the enzymes is to attach them to nanoparticles by applying the double-emulsion technique. In this work the polymer Eudragit® L 100-55 sensitive to pH was used to prepare laccase polymeric nanoparticles by the double-emulsion solvent evaporation approach. The size and morphology of the nanoparticles obtained was evaluated by Scanning Electron Microscope and particle size distribution was assessed by Photon Correlation Spectroscopy. Encapsulation efficiency and zeta potential were calculated. The effect of pH on laccase activity and stability was compared between free laccase and the immobilized one. Their stability was also determined in a sequential assay involving acidic pHs up to alkaline ones. The nanoparticles had a spherical shape with a mean size of 289 nm, zeta potential of -22.7 mV at pH 7.0, and load efficiency of 87%. The optimum pH of both free and immobilized laccases was 3.0, being the nanoparticles more stable at acidic pHs (2.0-4.0). Howevwe, this last kept 80% of enzyme activity at pH 2.0 approx., after 24 h. The polymer Eudragit® L 100-55 also conferred them resistance towards the pHs usually found at the gastrointestinal tract. These results suggest the potential use of nanoparticles as adjuvants in animal feed, serving as carriers for oral laccase delivery.

Objetivo. Identificar los tipos de bacterias que presentan mecanismos de resistencia a los antibióticos carbapenémicos. Metodología. Se recolectó en una base electrónica diseñada para tal fin, la información de los años 2014-2016 sobre mecanismos de resistencia a los carbapenémicos, obtenida de las boletas de los protocolos de identificación aplicados en el Laboratorio Nacional de Referencia. Boletas procedentes de la red de establecimientos para confirmación. Se realizaron tablas de frecuencias en el programa Epi Info versión 7, cada una de las muestras fue georreferenciada para su procesamiento y presentación en el programa Quantum GIS 2.18. Resultados. En 26 hospitales de El Salvador se han encontrado bacterias productoras de carbapenemasas, independiente de su complejidad o nivel de atención. La Región de Salud Metropolitana concentra el 45% (438) de las bacterias productoras de carbapenemasas. El agente identificado con más frecuencia fue el Acinetobacter baumannii con un 85% (807), seguido de Klebsiella pneumoniae con un 10% (97). Las secreciones representaron un 77% (731) de los sitios de aislamiento, seguida por los líquidos corporales estériles con un 19% (184). El mecanismo encontrado con mayor frecuencia fue carbapenemasa tipo oxacilinasa en un 63% (247), seguido de la metalo - betalactamasas en un 36% (140). Conclusiones. En el país, las bacterias productoras de carbapenemasas están presentes con predominio en los centros de la hospitalarios de la Región Metropolitana. Las especies bacterianas identificadas fueron, A. baumannii y K. pneumoniae, que han permanecido constantes durante el periodo de estudio y representan en un riesgo para la atención sanitaria. Alerta Año 2018, Vol. 1 No. 2: 8-15 Palabras claves: entero bacterias, resistencia bacteriana, carbapenemasas, Acinetobacter baumanni, Klebsiella pneumoniae.

IMMUNEPOTENT CRP is a dialyzable leukocyte extract obtained from bovine spleen with immunomodulatory and antitumour properties; therefore, when administrated as an adjuvant therapy for cancer patients, it has increased their survival and quality of life. The bioavailability of any orally administered compound can be reduced due to gastrointestinal enzymes. In this study, we evaluated if IMMUNEPOTENT CRP is resistant to the treatment with different enzymes (proteases, nucleases, polysaccharide-degrading enzymes or lipase), using as parameters for biological activity measurement its in vitro antitumour and antioxidant properties and in vivo the antitumour effect of IMMUNEPOTENT CRP treated with proteinase K. In conclusion, we consider necessary to include the antioxidant and cytotoxic activity on the MCF-7 cancer cell line as parameters for the quantitative determination of biological activity or potency tests for batch release. Additionally, the results showed that different enzymatic treatments do not affect the antitumour and antioxidant activities of IMMUNEPOTENT CRP in vitro, suggesting that this product can be administered orally without any loss of biological activity. Furthermore, IMMUNEPOTENT CRP treatment with proteinase K increases the antitumour activity in vivo.

Introducción. La inmunización con vacunas antineumocócicas conjugadas ha reducido los casos de enfermedad neumocócica invasiva por serotipos vacunales. Sin embargo, se ha observado paralelamente la enfermedad de reemplazo al reportarse casos causados por serotipos no vacunales. Objetivo. Describir la distribución de serotipos aislados de casos de enfermedad neumocócica invasiva en menores de 5 años en El Salvador, posterior a la introducción de vacunas antineumocócicas conjugadas. Metodología. Estudio descriptivo de la base de aislamientos de Streptococcus pneumoniae del Laboratorio Nacional de Referencia, provenientes de menores de 5 años con enfermedad neumocócica invasiva de 2011 a 2017. Los 61 serotipos aislados 29 se clasificaron como vacunales y como no vacunales 32, dependiendo si estaban contenidos o no en las vacunas antineumocócicas conjugadas 7 o 13 valente. Los datos fueron exportados a una hoja de cálculo de Microsoft Excel 2013, donde se analizó la información utilizando estadística descriptiva. Resultados. De 2011 a 2017 se reportaron 61 casos de enfermedad neumocócica invasiva en menores de 5 años, 29 de ellos por serotipos vacunales y 32 por serotipos no vacunales. Los vacunales presentaron una tendencia a la baja, registrándose cero casos durante 2016 y 2017. Los serotipos no vacunales presentaron una tendencia al alza. Los serotipos vacunales aislados con mayor frecuencia fueron 9V, 14 y 19A; mientras que los no vacunales fueron: 8, 10A, 15A y 18A. Conclusiones. Se observó una disminución en el número de casos de enfermedad neumocócica invasiva por serotipos vacunales de 2011 a 2017; paralelamente, se identificó la enfermedad de reemplazo.Alerta Año 2018, Vol. 1 No. 1: 11-17

Pleurotus ostreatus is an edible mushroom with many functional compounds. In previous studies, it has been shown that solid-state fermentation of Phaseolus vulgaris and Avena sativa by this fungus increases essential amino acids, diminishes antinutrients as well as improves the bioaccessibility of different compounds. The objective was to obtain a functional food based on biotransformed ingredients by solid-state fermentation with P. ostreatus and evaluate its properties and the effect the food processing has on them. Results showed that cookies made with fermented flours provide a higher antioxidant capacity, when compared with cookies made without fermented flours, while maintaining its antioxidant capacity after simulated digestion assay. They also showed higher content of bioavailable protein compared to wheat control cookie, higher fiber content and lower sugars compared to commercial cookies. Cookies had good sensorial acceptability. This study shows the potential use of biotransformed cereals and legumes by P. ostreatus in functional foods.

Functionalization of thin films with organic ligands has been the subject of intense research due to their potential application as heterogeneous molecular nanosystems. In this work, self-assembled monolayers of thiols (16-mercaptohexadecanoic acid and 11-mercaptoundecanol) were used to bind laccase (from Pycnoporus sanguineus CS43) to nanostructured gold thin films obtained by DC sputtering. Sputtering power, sputtering pressure and substrate temperature were optimized to enhance the activity of the immobilized biomolecules. Scanning electron microscopy, confocal microscopy, X-ray diffraction and UV-vis spectroscopy were used to characterize the SAM-functionalized gold substrates. Our results demonstrate that the highest immobilized enzyme activity values can be achieved on substrates of surface roughness ˜200 nm and Au particle size of about 14 nm. The outstanding quality of the as-prepared substrates makes them particularly attractive as bionanosensors.

Background Mortality due to tuberculosis (TB) has increased due to the development of drug resistance, the mechanisms of which have not been fully elucidated. Our research group identified a low expression of lipF gene in Mycobacterium tuberculosis clinical isolates with drug resistance. The aim of this work was to evaluate the effect of lipase F (LipF) expression on mycobacterial drug resistance. Results The effects of expressing lipF from Mycobacterium tuberculosis in Mycobacterium smegmatis on resistance to antituberculosis drugs were determined with resazurin microtiter assay plate and growth kinetics. Functionality of ectopic LipF was confirmed. LipF expression reduced the rifampicin (RIF) and streptomycin (STR) minimum inhibitory concentration (MIC) from 3.12 μg/mL to 1.6 μg/mL and 0.25 μg/mL to 0.06 μg/mL respectively, moreover a reduced M. smegmatis growth in presence of RIF and STR compared with that of a control strain without LipF expression (p p Conclusions LipF expression was associated with increased RIF and STR sensitivity in mycobacteria. Reduced LipF expression may contribute to the development of RIF and STR resistance in Mycobacterium species. Our findings provide information pertinent to understanding mycobacterial drug resistance mechanisms.

Laccases have attracted a great deal of interest because of their remarkable ability for the degradation of synthetic dyes present in wastewaters. New laccase producing sources with robust operational and functional properties are being continuously explored. In this work, the potential for the decolorization and detoxification of synthetic dyes was evaluated in two Mexican strains of the genus Trametes. The decolorization capacity of Trametes maxima LE130 and Trametes sp. LA1 was tested in solid and liquid media. The phytotoxicity of the degradation products was determined using Raphanus sativus and Pisum sativum seeds. In solid media, both strains showed a higher decolorization capacity (p ≤ 0.05) than Phanerochaete chrysosporium ATCC 24725, which is known to be very efficient in lignin and dye-degradation. They produced laccase as the main ligninolytic enzyme; T. maxima LE130 secreted a single isoform of 43.9 kDa, while Trametes sp. LA1 produced three isoforms of 67.3, 58.6 and 52.7 kDa, respectively. Trametes sp. LA1 culture fluids were capable of decolorizing and detoxifying chemically diverse dyes (anthraquinonic dye Remazol Brilliant Blue R, azoic Reactive Black 5 and triphenylmethane Crystal Violet) without the addition of redox mediators. Therefore, this could be considered as a new laccase source which could be potentially competitive in the bioremediation of dye-containing wastewaters.

The global rise in urbanization and industrial activity has led to the production and incorporation of foreign con‑ taminant molecules into ecosystems, distorting them and impacting human and animal health. Physical, chemical, and biological strategies have been adopted to eliminate these contaminants from water bodies under anthropo‑ genic stress. Biotechnological processes involving microorganisms and enzymes have been used for this purpose; specifcally, laccases, which are broad spectrum biocatalysts, have been used to degrade several compounds, such as those that can be found in the efuents from industries and hospitals. Laccases have shown high potential in the biotransformation of diverse pollutants using crude enzyme extracts or free enzymes. However, their application in bioremediation and water treatment at a large scale is limited by the complex composition and high salt concentra‑ tion and pH values of contaminated media that afect protein stability, recovery and recycling. These issues are also associated with operational problems and the necessity of large-scale production of laccase. Hence, more knowledge on the molecular characteristics of water bodies is required to identify and develop new laccases that can be used under complex conditions and to develop novel strategies and processes to achieve their efcient application in treating contaminated water. Recently, stability, efciency, separation and reuse issues have been overcome by the immobilization of enzymes and development of novel biocatalytic materials. This review provides recent information on laccases from diferent sources, their structures and biochemical properties, mechanisms of action, and applica‑ tion in the bioremediation and biotransformation of contaminant molecules in water. Moreover, we discuss a series of improvements that have been attempted for better organic solvent tolerance, thermo-tolerance, and operational stability of laccases, as per process requirements., Instituto de Fisiología Vegetal

ResumenIntroducciónLa elección la solución cardiopléjica óptima sigue siendo motivo de debate en la actualidad. La cardioplejía Del Nido (diseñada originariamente para la población pediátrica) está ganando popularidad en el campo de la cirugía cardiaca del adulto.MétodosSerie consecutiva de 30 pacientes que recibieron cardioplejía Del Nido como estrategia de protección miocárdica. Se registraron parámetros demográficos y de perfil de riesgo quirúrgico, tipo de procedimiento realizado, supervivencia perioperatoria; así como los principales parámetros de perfusión, variación de hematocrito intraoperatorio y liberación de enzimas de daño miocárdico durante el postoperatorio. Se determinaron los costes de elaboración de la formulación con respecto a los preparados comerciales convencionales.ResultadosLa serie presentó una supervivencia hospitalaria del 100%. La parada electromecánica del corazón fue efectiva en todos los casos. Los grupos de procedimientos realizados fueron cirugía combinada valvular/coronaria (43,34%), cirugía valvular simple (30%), cirugía coronaria aislada (13,34%) e intervenciones de más de 2 procedimientos (13,34%). Tras la reperfusión del miocardio se observó una tasa de desfibrilación espontánea del corazón del 83,34%. El destete de circulación extracorpórea se realizó con éxito en el 100%, sin necesidad de soporte circulatorio mecánico y con dosis bajas de soporte inotrópico con dobutamina. El coste estimado de elaboración se situó en 7,39 euros por cada unidad.ConclusionesLa cardioplejía Del Nido es de uso habitual en la práctica clínica tanto en la población pediátrica como en la adulta en centros de elevado volumen quirúrgico. Podría constituir una estrategia de protección miocárdica segura, eficaz y económica de aplicación universal en cirugía cardiaca. Son necesarios estudios adicionales de corte prospectivo para corroborar estos datos.AbstractIntroductionThe choice of the optimal cardioplegic solution is still under debate. Del Nido cardioplegia (originally designed for the paediatric population) is gaining popularity in the field of adult cardiac surgery.MethodsA study was conducted on a consecutive series of 30 patients who received Del Nido cardioplegia as myocardial protection strategy. Demographic and risk profile parameters, procedure performed, and surgical survival were registered, as well as main the perfusion variables, intraoperative haematocrit variation, and myocardial injury enzymatic release during the postoperative period. Formulation costs compared with conventional commercial solutions were determined.ResultsSurvival of the series was 100%. Electromechanical arrest of the heart was achieved in all cases. The group of procedures performed were combined valvular/coronary surgery (43.34%), isolated valve surgery (30.00%), coronary artery bypass graft surgery (13.34%), and interventions with more than 2 procedures (13.34%). After myocardial reperfusion, spontaneous defibrillation of the heart occurred in 83.34%. Weaning from cardiopulmonary bypass was successful in 100% with no mechanical circulatory support, and low-dose inotropic support with dobutamine. The estimated preparation costs were set at 7.39 euros per unit.ConclusionsDel Nido cardioplegia is routinely used in clinical practice both in paediatric and adult population in high volume centres. It could be a safe, effective and cheap myocardial protection strategy of universal implementation in cardiac surgery. Additional prospective studies are needed to confirm these data.

ResumenIntroducciónLa naturaleza heterogénea de la válvula aórtica bicúspide (VAB) y su asociación con la dilatación de la aorta ascendente ha sido reconocida en muchos estudios observacionales. El objetivo de nuestro estudio es valorar la asociación que tiene el patrón de aortopatía con la morfología y lesión valvular primaria de esta valvulopatía.MétodosDesde febrero del 2007 hasta noviembre del 2013, 107 pacientes con VAB y aneurisma de aorta ascendente fueron derivados a cirugía. Identificamos la morfología valvular intraoperatoriamente y la lesión valvular primaria por ecocardiografia. Con la tomografía preoperatoria realizamos mediciones en varios sectores de la aorta ascendente.ResultadosLa edad media al momento de la cirugía fue significativamente menor en enfermos con insuficiencia frente a estenosis aórtica (51 vs. 64 años, p

[EN] The aim of the research was to determine the impact of fermentation with Pleurotus ostreatus on kidney beans, black beans, and oats. The results indicate that the fungus has a positive effect on the substrates when compared to the controls. The antioxidant activity (39.5% on kidney beans and 225% on oats in relation to the controls) and content of total polyphenols (kidney beans three times higher regarding the controls) increased significantly by the presence of the fungus mycelium, even after simulated digestion. There was a significant increase in protein digestibility (from 39.99 to 48.13% in black beans, 44.06 to 69.01% in kidney beans, and 63.25 to 70.01% in oats) and a decrease of antinutrient tannins (from 65.21 to 22.07 mg in black beans, 35.54 to 23.37 in kidney beans, and 55.67 to 28.11 in oats) as well as an increase in the contents of some essential amino acids. Overall, this fermentation treatment with Pleurotus ostreatus improved the nutritional quality of cereals and legumes, making them potential ingredients for the elaboration and/or fortification of foods for human nutrition., We would like to thank Consejo Nacional de Ciencia y Tecnologa (CONACyT) for financially supporting E.E.-P to obtain her Ph.D. (scholarship 446871).

In this study, in-house isolated laccase isoforms, i.e., Lac-I and Lac-II of the basidiomycete Pycnoporus sanguineus (CS43), were evaluated in relation to their Remazol Brilliant Blue R (RBBR) dye degradation capacity. A modified Dhouib medium additionally supplemented with 3% ethanol as a secondary inducer was used to propagate P. sanguineus CS43 for enhanced production of laccase under liquid state fermentation. The crude laccase extract was purified by passing through ion exchange diethylaminoethanol (DEAE)-Sepharose and gel filtration-based Sephadex G-200 column chromatography. The purified laccase fractions were subjected to the electrophoresis, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed two laccase isoforms Lac-I and Lac-II with 66 and 68 kDa, respectively. To explore the industrial applicability, for RBBR dye, degradation efficiencies ranged from 82 to 88% after 3 h of incubation for both; Lac-I and Lac-II at both concentrations were recorded. However, with 8 U/mL, the degradation ranged between 70 to 80% during the first 5 min of incubation. Enhanced degradation of RBBR dye was obtained in the presence of violuric acid and N-hydroxypthalamide as laccase mediators. Finally, using RBBR as a substrate kinetic characterization of both Lac-I and Lac-II isoforms was performed that revealed K m (0.243 and 0.117 mM for Lac-I and Lac-II) and V max (1.233 and 1.012 mM/Sec for Lac-I and Lac-II) values, respectively.

Laccases are enzymes that have the ability to catalyze the oxidation of a wide spectrum of phenolic compounds with the four-electron reduction of molecular oxygen to water. The active site of those proteins contains four copper ions, classified into three types. Laccases are interesting enzymes for study from the point of view of their structure, function and application because of their role in lignin degradation. Structural studies of two thermostable laccases produced by the strain Pycnoporus sanguineus CS43 (PsLacI and PsLacII) were performed. Both isoforms of PsLac show high thermal stability, at 60°C and 50°C, respectively, and they remained active at a high concentration of organic solvents. However, PsLacI has a higher thermal and pH stability and tolerance against inhibitors, and is a more efficient catalyst for ABTS and DMP (laccases substrate) than PsLacII. Based on the determined crystal structures we achieved insights into the structural factors relevant for the enzymatic properties of PsLacI and PsLacII. N-glycosylation site Asn354, which is very often present in structures of fungal laccases from other species, was not present in PsLac. This observation may be of particular significance due to the close distance between Asn354 and the substrate-binding pocket. This results in better access to the hydrophobic cavity for a particular substrate. Furthermore, we identified significant differences in the region of substrate-binding pocket, which confer PsLacI a markedly better performance than PsLacII.

Laccases have attracted a great deal of interest because of their remarkable ability for the degradation of synthetic dyes present in wastewaters. New laccase producing sources with robust operational and functional properties are being continuously explored. In this work, the potential for the decolorization and detoxification of synthetic dyes was evaluated in two Mexican strains of the genus Trametes. The decolorization capacity of Trametes maxima LE130 and Trametes sp. LA1 was tested in solid and liquid media. The phytotoxicity of the degradation products was determined using Raphanus sativus and Pisum sativum seeds. In solid media, both strains showed a higher decolorization capacity (p &le, 0.05) than Phanerochaete chrysosporium ATCC 24725, which is known to be very efficient in lignin and dye-degradation. They produced laccase as the main ligninolytic enzyme, T. maxima LE130 secreted a single isoform of 43.9 kDa, while Trametes sp. LA1 produced three isoforms of 67.3, 58.6 and 52.7 kDa, respectively. Trametes sp. LA1 culture fluids were capable of decolorizing and detoxifying chemically diverse dyes (anthraquinonic dye Remazol Brilliant Blue R, azoic Reactive Black 5 and triphenylmethane Crystal Violet) without the addition of redox mediators. Therefore, this could be considered as a new laccase source which could be potentially competitive in the bioremediation of dye-containing wastewaters.

The NSP4 protein is a multifunctional protein that plays a role in the morphogenesis and pathogenesis of the rotavirus. Although NSP4 is considered an enterotoxin, the relationship between gastroenteritis severity and amino acid variations in NSP4 of the human rotavirus remains unclear. In this study, we analyzed the sequence diversity of NSP4 and the severity of gastroenteritis of children with moderate to severe gastroenteritis. The rotavirus-infected children were hospitalized before the rotavirus vaccine program in Mexico. All children had diarrhea within 1−4 days, 44 (88%) were vomiting and 35 (70%) had fevers. The severity analysis showed that 13 (26%) cases had mild gastroenteritis, 23 (46%) moderate gastroenteritis and 14 (28%) severe. NSP4 phylogenetic analysis showed three clusters within the genotype E1. Sequence analysis revealed similar mutations inside each cluster, and an uncommon variation in residue 144 was found in five of the Mexican NSP4 sequences. Most of the amino acid variations were located in the VP4 and VP6 binding site domains, with no relationship to different grades of gastroenteritis. This finding indicates that severe gastroenteritis caused by the rotavirus appears to be related to diverse viral or cellular factors instead of NSP4 activity as a unique pathogenic factor.

Laccase from Pycnoporus sanguineus CS43 was successfully immobilized onto Immobead-150 and Eupergit-C by covalent binding and by entrapment in LentiKats. The highest immobilization was onto Immobead-150 (97.1±1.2%) compared to the other supports, LentiKats (89±1.1%) and Eupergit-C (83.2±1.4%). All three immobilized enzyme systems showed increased thermostability and better mechanical properties than free laccase. Moreover, after 5 cycles of reuse of these systems, 90% of initial laccase activity was retained. Immobead-150 and LentiKats systems exhibited the highest efficiencies in removal of m-cresol under the combined actions of biodegradation and adsorption, while laccase entrapped in LentiKats showed a high ability for degradation of m-cresol within 24h. In addition, the typical Michaelis-Menten enzymatic model effectively described the kinetic profile of m-cresol degradation by the enzyme entrapped in LentiKats. Based on the results obtained in the present study, it can be established that the immobilized biocatalysts developed here possess significant potential for wastewater treatment.

Rotavirus vaccine was developed using the most prominent G and P genotypes circulating in children population. Therefore, severe gastroenteritis has been reduced around the world. This study investigated the G and P rotavirus genotypes circulating in children from two hospitals in the city of Chihuahua, Mexico. Additionally, polyclonal antibodies against Rotavirus Wa strain were used to determine their homotypic and heterotypic reactivity to both P[8] and P[4] genotypes. G1, G2, and G3 VP7 genotypes and P[8] and P[4] VP4 genotypes were detected in common and uncommon combinations as well as mixed infectious. The predominant combination was G1P[8]. Phylogenetic analysis of VP4 gene revealed the presence of P[8]-1 and P[8]-3 lineages of P[8] genotype and P[4]-5 lineage of P[4] genotype. All but five G1P[8] rotavirus were detected by polyclonal anti-Rotavirus Wa strain. Mutation analysis revealed differences in three of the four neutralizing epitopes previously reported to VP8* subunit of VP4 protein. Results of this study offer insights over genetic variants of field rotavirus that could be detected in a homotypic and heterotypic way by antibodies elicited to rotavirus with P[8] genotype. [Int Microbiol 2016; 19(1):27-32].

We extracted and purified oil peach kernels in order to recommend its use from chemical and technological points of view. The purification includes degumming, neutralization, in which the oil contacts caustic soda solution at 12.14 and 16º Bé. Following is bleaching, where the neutralized oil is treated with bleaching different proportions. Bleaching is obtained using a percentage of land of 1.5%, the lowest rate of peroxide - 2.03 meq O2 kg-1 - and an acidity of 0.08% as oleic acid. The major fatty acids found were 77.9% oleic and 15.5% linoleic. The refined oil is more stable than the crude oil and its use can be recommended in the manufacture of various chemicals prior to an exhaustive toxicological evaluation.

Sphingomyelinase (SMase) activity was measured in Entamoeba histolytica particulate and soluble subcellular fractions. The effects on SMase of incubation time, total protein concentration, pH, and several divalent cations were determined. SMase-C and other unidentified esterase activity were detected in soluble and particulate fractions. SMase-C was 94.5-96.0% higher than the unidentified esterase activity. Soluble and insoluble SMase-C specific activities increased with protein dose and incubation time. Soluble and insoluble SMase-C activities were maximum at pH 7.5 and were dependent on Mg(2+), Mn(2+), or Co(2+), and inhibited by Zn(2+), Hg(2+), Ca(2+), and EDTA. SMase-C was active in the pH range of 3-10 and its maximum activity was at pH 7.5. The soluble and insoluble SMases have remarkably similar physicochemical properties, strongly suggesting that E. histolytica has just one isoform of neutral SMase-C that had not been described before and might be essential for E. histolytica metabolism or virulence.

EARTH University is a small agronomic university with a theme of sustainability in eastern Costa Rica. Several natural and constructed wetlands on its campus are used for research, water quality improvement, and higher education. It has become an important location for research and teaching on humid tropical wetland ecology and management. A 112-ha flow-through Raphia taedigera (Arecaceae) forested wetland is being used for climate change research, focusing on carbon sequestration and methane generation. Methane emissions are measured seasonally and are comparable to rates in tropical wetlands published elsewhere. Carbon sequestration by the wetland appears to be substantially higher than similar flow-through temperate zone wetlands. Treatment wetlands are used on campus to improve water quality of effluents from an animal farm, a dairy plant, a landfill, and a banana paper plant. Water quality was substantially improved in all of these wetlands except the landfill leachate wetland. All of these campus wetlands have been integrated into the four-year education program of EARTH University and 22 undergraduate projects have been completed on wetlands over the past 14 years.

Flocculation is an important ability of some yeasts used in the alcohol fermentation industry. This characteristic depends on the presence and activity of FLO genes, which encode for several proteins called zymolectins. To identify the type of FLO genes present in some lager and wild yeasts, we designed specific primers for PCR amplification of seven FLO genes. DNA samples were obtained from six lager, one baker's, and three wild Saccharomyces strains. Our results showed that the incidence of flocculation genes is variable. Only FLO11 was present in all yeast strains. In contrast, Lg-FLO was detected exclusively in lager strains, but they lacked the FLO5 gene. FLO8 was present in all except the baker's strain, whereas FLO1, -9, and -10 showed a polymorphic distribution. Analysis of FLO gene content and flocculation ability indicated that the number of different FLO genes is related to the intensity of flocculation. Therefore, detection of FLO genes could provide a valuable tool for yeast strain selection.

A survey to isolate native white rot basidiomycetes from Northeast Mexico was conducted in the forests of the Sierra Madre Oriental in the state of Nuevo Leon. A total of 92 isolates from at least 20 different genera, were screened on Bran-Flakes solid plate cultures for the production of ligninolytic oxidases and/or peroxidases with guaiacol and o-anisidine as substrates; their lignin depolymerizing potential using the polymeric dye Poly R 478; their ability to decolorize anthraquinonic (Remazol Brilliant Blue Reactive), azo (Acid Red 44) and triphenylmethane (Crystal Violet) dyes. Among all fungi tested, 15 isolates showed extensive decolorization of the three dyes within a week and gave a positive reaction in guaiacol and o-anisidine tests. Nine of them were also efficient degraders of Poly R-478. Two isolates (CS5 and CU1) showed decolorization of all dyes within 5 days, comparing favorably with reference strains of P. chrysosporium, Pleurotus ostreatus, and Bjerkandera adusta. Decolorization was associated with laccase activity in both isolates and reached 90% or more for all dyes within 24 h in 8-day-old liquid cultures. The coupling of pairs 2,4-dichlorophenol + 4-aminoantipyrine and 3-dimethylaminobenzoic acid + 3-methyl-2-benzothiazolinone hydrazone, strongly suggest that the laccases of both strains correspond to those considered of high redox potential. These strains are considered good candidates for bioremediation of dye polluted effluents due to their ligninolytic potential and decolorizing performance.