18 research outputs found

    Péptidos y proteínas de la leche con propiedades funcionales

    Get PDF
    La fracción proteica de la leche contiene un gran número de compuestos biológicamente activos. Además de lasproteínas de la leche, caseínas y proteínas del suero lácteo, existen también pequeñas cantidades de otras proteínasy péptidos. Estos péptidos, que son inactivos dentro de la secuencia de la proteína nativa, pueden ser liberados porhidrólisis enzimática, por ejemplo, durante la digestión gastrointestinal o durante el procesado del alimento. Estospéptidos bioactivos procedentes de proteínas lácteas presentan una actividad moduladora de numerosos procesosmetabólicos del organismo. Asimismo, las proteínas del suero lácteo representan una mezcla variada de proteínassecretadas, tales como á-lactoalbúmina, â-lactoglobulina, lactoferrina, lactoperoxidasa, inmunoglobulinas,glicomacropéptido y una gran cantidad de factores de crecimiento. Estas proteínas tienen una serie de efectosbiológicos, que van desde un efecto anticancerígenos hasta efectos en la función digestiva

    Regarding the rejection performance of a polymeric reverse osmosis membrane for the final purification of two-phase olive mill effluents previously treated by an advanced oxidation process

    Get PDF
    In previous works on olive mill wastewater (OMW), secondary advanced oxidation treatment solved the problem related to the presence of phenolic compounds and considerable chemical oxygen demand. However, the effluent presented a significant salinity after this treatment. In this work, an adequate operation of a reverse osmosis (RO) membrane is addressed to ensure constant performance over a long period of time. In this paper, the effect of the operating parameters on the dynamic membrane rejection performance towards the target species was examined and discussed. Rejection efficiencies of all species were observed to follow a similar pattern, which consisted of slight initial improvement that further decreased over time. Rejection of both divalent ions remained constant at over 99% regardless of the operating conditions. Rejections were noticed to follow the order SO42- > Cl- > NO3- and Ca2+ > Mg2+> K+> Na+, as a rule. Divalent species were moderately more highly rejected than monovalent ones, in accordance with their higher charge and molecular size, and sulfate anions were consistently rejected by over 99%. Finally, the RO membrane exiting treated effluent was depleted of the high electro conductivity initially present (above 97% rejection), permitting its re-use as good quality irrigation water (below 1 mS/cm)

    Sobre la eficiencia del rechazo de una membrana polimérica de ósmosis inversa para la purificación del agua residual de almazara de dos fases, previamente tratada mediante un proceso avanzado de oxidación

    Get PDF
    In previous works on olive mill wastewater (OMW), secondary advanced oxidation treatment solved the problem related to the presence of phenolic compounds and considerable chemical oxygen demand. However, the effluent presented a significant salinity after this treatment. In this work, an adequate operation of a reverse osmosis (RO) membrane is addressed to ensure constant performance over a long period of time. In this paper, the effect of the operating parameters on the dynamic membrane rejection performance towards the target species was examined and discussed. Rejection efficiencies of all species were observed to follow a similar pattern, which consisted of slight initial improvement that further decreased over time. Rejection of both divalent ions remained constant at over 99% regardless of the operating conditions. Rejections were noticed to follow the order SO42- > Cl- > NO3- and Ca2+ > Mg2+> K+> Na+, as a rule. Divalent species were moderately more highly rejected than monovalent ones, in accordance with their higher charge and molecular size, and sulfate anions were consistently rejected by over 99%. Finally, the RO membrane exiting treated effluent was depleted of the high electro conductivity initially present (above 97% rejection), permitting its re-use as good quality irrigation water (below 1 mS/cm).En trabajos previos con agua residual de almazara, se solucionó el problema en relación a la presencia de compuestos fenólicos y la considerable concentración de material orgánico. Sin embargo, el efluente presentaba una salinidad significativa tras éste. Este trabajo tiene por objetivo estudiar la adecuada operación de una membrana de ósmosis inversa (OI) para asegurar rendimientos constantes por largos períodos de tiempo de operación. Se examina y discute el efecto de los parámetros de operación en el rendimiento dinámico del rechazo de especies diana. Se observó que la eficiencia de rechazo de todas las especies siguió un patrón similar, consistente en una mejora inicial que posteriormente minoró con el tiempo de operación. El rechazo de iones divalentes se mantuvo constante sobre 99% independientemente de las condiciones de operación. La selectividad del rechazo siguió el orden SO42- > Cl- > NO3- y Ca2+ > Mg2+ > K+> Na+ en general. Las especies divalentes fueron moderadamente más rechazadas que las monovalentes, en concordancia con su mayor carga y tamaño molecular, y los iones sulfato fueron consistentemente rechazados al 99%. Finalmente, el efluente a la salida de la membrana de OI se encontraba exento de los altos valores de conductividad inicialmente presentes (rechazo superior al 97%), permitiendo su reutilización como agua de regadío de buena calidad (inferior a 1 mS/cm)

    Componentes biológicamente activos de la leche materna

    Get PDF
    La leche materna es un complejo fluido biológico que aporta la energía y los nutrientes esenciales para el desarrolloy crecimiento del recién nacido. Pero además, la leche materna contiene toda una serie de compuestos bioactivoscomo enzimas, hormonas, factores de crecimiento, proteínas específicas, poliaminas, nucleótidos, oligosacáridos, etc.,que ejercen efectos biológicos y que en conjunto reciben el nombre de “factores tróficos de la leche”. Estos compuestosbiactivos son considerados nutrientes potencialmente esenciales en periodos de desarrollo y en determinadasenfermedades, cuando la capacidad de síntesis no supera las necesidades de los mismos. Aunque las fórmulasinfantiles aportan todos los nutrientes para un adecuado desarrollo del recién nacido, carecen de muchos de estoscompuestos. Este artículo pretende realizar una revisión acerca de los conocimientos actuales sobre los efectosbiológicos de la lactoferrina, nucleótidos, poliaminas y oligosacáridos

    Recovery of iron after Fenton-like secondary treatment of olive mill wastewater by nano-filtration and low-pressure reverse osmosis membranes

    Get PDF
    In this work, the performances of novel nano-filtration (NF) and low-pressure reverse osmosis (RO) polymeric membranes were examined with the aim of recovering the iron used as catalyst in former secondary treatment based on the Fenton-like advanced oxidation of olive mill wastewater (OMW). Results highlight that both membranes exhibit a good performance towards the rejection of iron (99.1% for the NF membrane <em>vs.</em> 100% for the low-pressure RO membrane) in the secondary-treated OMW effluent, thus permitting the recovery of iron in the concentrate stream in order to recycle it back into the oxidation reactor to reduce catalyst consumption. Finally, the permeate streams could be re-used for irrigation. Major productivity was observed by the selected NF membrane, about 47.4 L/hm<sup>2</sup> upon 9 bar, whereas 30.9 L/hm<sup>2</sup> could be yielded with the RO membrane under an operating pressure of 8 bar. Moreover, a sensibly lower fouling index was measured on the NF membrane (0.0072 in contrast with 0.065), which ensures major steady-state performance on this membrane and a longer service lifetime. This also results in lower required membrane area and membrane plant over dimension (4 modules in case of RO operation whereas only 2 modules for NF).<br><br>En este trabajo, se examinó el rendimiento de membranas modernas de nanofiltración (NF) y ósmosis inversa (OI) poliméricas con el objetivo de recuperar el hierro utilizado como catalizador en un tratamiento secundario previo de agua residual oleícola (OMW) basado en oxidación avanzada tipo Fenton. Los resultados ponen de relieven que ambas membranas exhiben buen rendimiento en cuanto al rechazo de hierro (99.1 % para la membrana de NF vs. 100 % para la membrana de OI de bajas presiones) en el efluente oleícola tras tratamiento secundario, permitiendo en consecuencia la recuperación de hierro en la corriente de concentrado para su recirculación de nuevo al reactor de oxidación para reducir el consumo de catalizador. Finalmente, las corrientes de permeado podrían ser reutilizadas para riego. Por otro lado, la productividad asegurada por la membrana de NF seleccionada fue mayor, en torno a 47.4 L/hm<sup>2</sup> a 9 bar, mientras que 30.9 L/hm<sup>2</sup> pudieron ser producidos por la membrana de OI bajo una presión operativa de 8 bar. Además, un índice de fouling sensiblemente menor fue medido en la membrana de NF (0.0072 en contraste con 0.065), lo que asegura mayor rendimiento en estado estacionario para esta membrana, y mayor vida de servicio. Además, ello también resultó en una menor área de membrana y sobredimensionamiento de la planta requeridas (4 módulos en caso de OI mientras que sólo para NF)

    Fructooligosacharides Reduce Pseudomonas aeruginosa PAO1 Pathogenicity through Distinct Mechanisms

    Get PDF
    Pseudomonas aeruginosa is ubiquitously present in the environment and acts as an opportunistic pathogen on humans, animals and plants. We report here the effects of the prebiotic polysaccharide inulin and its hydrolysed form FOS on this bacterium. FOS was found to inhibit bacterial growth of strain PAO1, while inulin did not affect growth rate or yield in a significant manner. Inulin stimulated biofilm formation, whereas a dramatic reduction of the biofilm formation was observed in the presence of FOS. Similar opposing effects were observed for bacterial motility, where FOS inhibited the swarming and twitching behaviour whereas inulin caused its stimulation. In co-cultures with eukaryotic cells (macrophages) FOS and, to a lesser extent, inulin reduced the secretion of the inflammatory cytokines IL-6, IL-10 and TNF- a . Western blot experiments indicated that the effects mediated by FOS in macrophages are associated with a decreased activation of the NF- k B pathway. Since FOS and inulin stimulate pathway activation in the absence of bacteria, the FOS mediated effect is likely to be of indirect nature, such as via a reduction of bacterial virulence. Further, this modulatory effect is observed also with the highly virulent ptxS mutated strain. Co-culture experiments of P. aeruginosa with IEC18 eukaryotic cells showed that FOS reduces the concentration of the major virulence factor, exotoxin A, suggesting that this is a possible mechanism for the reduction of pathogenicity. The potential of these compounds as components of antibacterial and anti-inflammatory cocktails is discussed.The authors acknowledge financial support from FEDER funds and Fondo Social Europeo through grants from the Spanish Ministry of Economy and Competitiveness (grants SAF2011-22922, SAF2011-22812) the Andalusian regional government Junta de Andalucía (grant CVI-7335) and the Centre of Networked Biomedical Research on Hepatic and Digestive Diseases (CIBERehd) which is funded by the Carlos III Health Institute and the Ramón Areces Foundation, Spain

    Phylogenetic and Evolutionary Patterns in Microbial Carotenoid Biosynthesis Are Revealed by Comparative Genomics

    Get PDF
    BACKGROUND: Carotenoids are multifunctional, taxonomically widespread and biotechnologically important pigments. Their biosynthesis serves as a model system for understanding the evolution of secondary metabolism. Microbial carotenoid diversity and evolution has hitherto been analyzed primarily from structural and biosynthetic perspectives, with the few phylogenetic analyses of microbial carotenoid biosynthetic proteins using either used limited datasets or lacking methodological rigor. Given the recent accumulation of microbial genome sequences, a reappraisal of microbial carotenoid biosynthetic diversity and evolution from the perspective of comparative genomics is warranted to validate and complement models of microbial carotenoid diversity and evolution based upon structural and biosynthetic data. METHODOLOGY/PRINCIPAL FINDINGS: Comparative genomics were used to identify and analyze in silico microbial carotenoid biosynthetic pathways. Four major phylogenetic lineages of carotenoid biosynthesis are suggested composed of: (i) Proteobacteria; (ii) Firmicutes; (iii) Chlorobi, Cyanobacteria and photosynthetic eukaryotes; and (iv) Archaea, Bacteroidetes and two separate sub-lineages of Actinobacteria. Using this phylogenetic framework, specific evolutionary mechanisms are proposed for carotenoid desaturase CrtI-family enzymes and carotenoid cyclases. Several phylogenetic lineage-specific evolutionary mechanisms are also suggested, including: (i) horizontal gene transfer; (ii) gene acquisition followed by differential gene loss; (iii) co-evolution with other biochemical structures such as proteorhodopsins; and (iv) positive selection. CONCLUSIONS/SIGNIFICANCE: Comparative genomics analyses of microbial carotenoid biosynthetic proteins indicate a much greater taxonomic diversity then that identified based on structural and biosynthetic data, and divides microbial carotenoid biosynthesis into several, well-supported phylogenetic lineages not evident previously. This phylogenetic framework is applicable to understanding the evolution of specific carotenoid biosynthetic proteins or the unique characteristics of carotenoid biosynthetic evolution in a specific phylogenetic lineage. Together, these analyses suggest a "bramble" model for microbial carotenoid biosynthesis whereby later biosynthetic steps exhibit greater evolutionary plasticity and reticulation compared to those closer to the biosynthetic "root". Structural diversification may be constrained ("trimmed") where selection is strong, but less so where selection is weaker. These analyses also highlight likely productive avenues for future research and bioprospecting by identifying both gaps in current knowledge and taxa which may particularly facilitate carotenoid diversification

    Recovery of iron after Fenton-like secondary treatment of olive mill wastewater by nano-filtration and low-pressure reverse osmosis membranes

    Get PDF
    In this work, the performances of novel nano-filtration (NF) and low-pressure reverse osmosis (RO) polymeric membranes were examined with the aim of recovering the iron used as catalyst in former secondary treatment based on the Fenton-like advanced oxidation of olive mill wastewater (OMW). Results highlight that both membranes exhibit a good performance towards the rejection of iron (99.1% for the NF membrane <em>vs.</em> 100% for the low-pressure RO membrane) in the secondary-treated OMW effluent, thus permitting the recovery of iron in the concentrate stream in order to recycle it back into the oxidation reactor to reduce catalyst consumption. Finally, the permeate streams could be re-used for irrigation. Major productivity was observed by the selected NF membrane, about 47.4 L/hm<sup>2</sup> upon 9 bar, whereas 30.9 L/hm<sup>2</sup> could be yielded with the RO membrane under an operating pressure of 8 bar. Moreover, a sensibly lower fouling index was measured on the NF membrane (0.0072 in contrast with 0.065), which ensures major steady-state performance on this membrane and a longer service lifetime. This also results in lower required membrane area and membrane plant over dimension (4 modules in case of RO operation whereas only 2 modules for NF).<br><br>En este trabajo, se examinó el rendimiento de membranas modernas de nanofiltración (NF) y ósmosis inversa (OI) poliméricas con el objetivo de recuperar el hierro utilizado como catalizador en un tratamiento secundario previo de agua residual oleícola (OMW) basado en oxidación avanzada tipo Fenton. Los resultados ponen de relieven que ambas membranas exhiben buen rendimiento en cuanto al rechazo de hierro (99.1 % para la membrana de NF vs. 100 % para la membrana de OI de bajas presiones) en el efluente oleícola tras tratamiento secundario, permitiendo en consecuencia la recuperación de hierro en la corriente de concentrado para su recirculación de nuevo al reactor de oxidación para reducir el consumo de catalizador. Finalmente, las corrientes de permeado podrían ser reutilizadas para riego. Por otro lado, la productividad asegurada por la membrana de NF seleccionada fue mayor, en torno a 47.4 L/hm<sup>2</sup> a 9 bar, mientras que 30.9 L/hm<sup>2</sup> pudieron ser producidos por la membrana de OI bajo una presión operativa de 8 bar. Además, un índice de fouling sensiblemente menor fue medido en la membrana de NF (0.0072 en contraste con 0.065), lo que asegura mayor rendimiento en estado estacionario para esta membrana, y mayor vida de servicio. Además, ello también resultó en una menor área de membrana y sobredimensionamiento de la planta requeridas (4 módulos en caso de OI mientras que sólo para NF)

    Blue-green neutrophilic inclusion bodies with concurrent liver failure as a predictor of imminent death

    No full text
    Blue-green, birefractory, poorly-defined, cytoplasmic inclusions in some types of leukocytes are an underdiagnosed finding, which composition and clinical significance is not well understood. Inclusions are only found on peripheral blood smear (PBS)
    corecore