Primer registro de Stenopyrgota crassitibia (Diptera: Pyrgotidae) para México

Se realizó una revisión del material entomológico depositado en la Colección Nacional de Insectos del Instituto de Biología (UNAM), donde se encontró un ejemplar de Stenopyrgota crassitibia Aczél, 1956 lo que constituye el primer registro de esta especie para México

Bacterial cellulose matrices to develop enzymatically active paper

This work studies the suitability of bacterial cellulose (BC) matrices to prepare enzymatically active nanocomposites, in a framework of more environmentally friendly methodologies. After BC production and purification, two kind of matrices were obtained: BC in aqueous suspension and BC paper. A lipase was immobilised onto the BC matrices by physical adsorption, obtaining Lipase/BC nanocomposites. Neither morphology nor crystallinity, measured by scanning electron microscopy (SEM) and X-Ray diffractometry (XRD) respectively, of the BC were affected by the binding of the protein. The activity of Lipase/BC suspension and Lipase/BC paper was tested under different conditions, and the operational properties of the enzyme were evaluated. A shift towards higher temperatures, a broader pH activity range, and slight differences in the substrate preference were observed in the immobilised lipase, compared with the free enzyme. Specific activity was higher for Lipase/BC suspension (4.2 U/mg) than for Lipase/BC paper (1.7 U/mg) nanocomposites. However, Lipase/BC paper nanocomposites showed improved thermal stability, reusability, and durability. Enzyme immobilised onto BC paper retained 60% of its activity after 48 h at 60 ºC. It maintained 100% of the original activity after being recycled 10 times at pH 7 at 60 ºC and it remained active after being stored for more than a month at room temperature. The results suggested that lipase/BC nanocomposites are promising biomaterials for the development of green biotechnological devices with potential application in industrials bioprocesses of detergents and food industry and biomedicine. Lipase/BC paper nanocomposite might be a key component of bioactive paper for developing simple, handheld, and disposable devices

Development of an antimicrobial bioactive paper made from bacterial cellulose

Bacterial cellulose (BC) has emerged as an attractive adsorptive material for antimicrobial agents due to its fine network structure, its large surface area, and its high porosity. In the present study, BC paper was first produced and then lysozymewas immobilized onto it by physical adsorption, obtaining a composite of lysozyme-BC paper. The morphology and the crystalline structure of the composite were similar to that of BC paper as examined by scanning electron microscopy and X-ray diffraction, respectively. Regarding operational properties, specific activities of immobilized and free lysozymewere similar. Moreover, immobilized enzyme showed a broaderworking temperature and higher thermal stability. The composites maintained its activity for at least 80 dayswithout any special storage. Lysozyme-BC paper displayed antimicrobial activity against Gram-positive and Gram-negative bacteria, inhibiting their growth by 82% and 68%, respectively. Additionally, the presence of lysozyme increased the antioxidant activity of BC paper by 30%. The results indicated that BC is a suitable material to produce bioactive paper as it provides a biocompatible environment without compromising the activity of the immobilized protein. BC paper with antimicrobial and antioxidant properties may have application in the field of active packaging

Bacterial Cellulose-Chitosan paper with antimicrobial and antioxidant activities

The production of paper-based bacterial cellulose-chitosan (BC-Ch) nanocomposites was accomplished following two different approaches. In the first, BC paper sheets were produced and then immersed in an aqueous solution of chitosan (BC-ChI); in the second, BC pulp was impregnated with chitosan prior to the production of paper sheets (BC-ChM). BC-Ch nanocomposites were investigated in terms of physical characteristics, antimicrobial and antioxidant properties, and the ability to inhibit the formation of biofilms on their surface. The two types of BC-Ch nanocomposites maintained the hydrophobic character, the air barrier properties, and the high crystallinity of the BC paper. However, BC-ChI showed a surface with a denser fiber network and with smaller pores than those of BC-ChM. Only 5% of the chitosan leached from the BC-Ch nanocomposites after 96 h of incubation in an aqueous medium, indicating that it was well retained by the BC paper matrix. BC-Ch nanocomposites displayed antimicrobial activity, inhibiting growth of and having a killing effect against bacteria Staphylococcus aureus and Pseudomonas aeruginosa and yeast Candida albicans. Moreover, BC-Ch papers showed activity against the formation of a biofilm on their surface. The incorporation of chitosan increased the antioxidant activity of the BC paper. Paper-based BC-Ch nanocomposites combined the physical properties of BC paper and the antimicrobial, antibiofilm, and antioxidant activities of chitosan

Laccase/TEMPO-mediated bacterial cellulose functionalization: production of paper-silver nanoparticles composite with antimicrobial activity

Bacterial cellulose (BC) was functionalized applying the Laccase/TEMPO oxidative treatment, leading to a five-fold increase of the concentration of carboxyl groups. Paper produced with this cellulose showed improved mechanical properties while maintaining barrier function against water and greases as compared to paper produced with non-oxidized BC. Also, the negative charge provided by the carboxyl groups on functionalized BC was used to generate silver nanoparticles (AgNPs), obtaining a BC paper and Ag composite. The presence of AgNPs in the composites was validated by SEM, EDS and ICP analysis, showing spherical, uniformly sized particles stabilized in the BC nanofibers matrix. Additionally, antimicrobial property of composites containing AgNPs was tested. The results showed the strong antimicrobial activity of the composites against Gram-positive and Gram-negative bacteria and fungi. The generation of Ag nanoparticles in a matrix that combine the physical characteristics of the BC nanofibers with the stiffness and the mechanical properties of paper produced composites that may have applicability in technological and biomedical uses

Bacterial cellulose for increasing barrier properties of paper products

Bacterial cellulose was combined with wood cellulose papers in order to obtain biomaterials with increased barrier properties. For this purpose, different parameters were assessed: two producing bacterial strains (Komagataeibacter xylinus and Gluconacetobacter sucrofermentans), two paper supports to hold bacterial cellulose (filter paper and eucalyptus paper), two kinds of combined biomaterials (composite and bilayer) and two drying temperatures (90ºC and room temperature). Papers with increased barrier properties (100º of water contact angle, 1220s of water drop test and air permeability ˂1µm (Pa·s)-1) were obtained by the addition of bacterial cellulose to each paper support. However, due to the lower initial barrier properties of filter paper, higher improvements were produced with this paper. In addition, bacterial cellulose provided smoother surfaces with higher gloss without a detrimental effect on physical properties. Higher resistance to water absorption was obtained with K. xylinus possibly explained by its longer size fibers than G. sucrofermentans, as analysed by SEM. Smoothness and gloss were specially increased in the bilayer biomaterial although resistance to air and water were further improved in the composite. In this biomaterial drying at high temperature had a detrimental effect. SEM analysis of the products obtained showed the intimate contact among fibers of bacterial cellulose and wood paper. Results obtained show the contribution of bacterial cellulose to improve the properties of paper and its potential for the design of new added value paper products from biomass

IgE-reactivity pattern of tomato seed and peel nonspecific lipid-transfer proteins after in vitro gastrointestinal digestion

The influence of gastrointestinal digestion on the immunological properties of three different nonspecific lipid-transfer proteins (nsLTPs) described in tomato fruit has been assessed using an in vitro system mimicking the stomach and intestine digestion conditions. Tomato peel/pulp nsLTP, Sola l 3, was degraded after digestion, although the immunoglobulin E (IgE) recognition of intact protein and a 10 kDa band were still observed after 30 min of duodenal digestion in the presence of phosphatidylcholine. The tomato seed nsLTP, Sola l 7, showed a higher stability than the other seed allergen, Sola l 6, during digestion. Sola l 7 showed an IgE immunoreactive 6.5 kDa band in immunoblotting analysis, retaining up to 7% of its IgE-binding capacity in inhibition ELISA test after 60 min of duodenal digestion and keeping intact its ability to activate basophils after digestion. These results suggest that the tomato seed allergen Sola l 7 might be considered as an important allergen in the induction of allergic responses to tomato due to its high stability against gastrointestinal digestion.This work was supported by grants SAF2017-86483-R from the Ministerio de Economía y Competitividad and PI13/00928 Instituto de Salud Carlos III (ISCIII), ISCIII cofounded by Fondo Europeo de Desarrollo Regional – FEDER for the Thematic Networks and Co-operative Research Centres; RIRAAF RD16/0006/0024 and ARADyAL (RD16/0006/0001; RD16/0006/0013; RD16/0006/0014); and EAACI Exchange Research Fellowship 2016. The authors would like to thank the excellent technical support of Sara Abián. S.B. was supported by a Juan de la Cierva Incorporación contract from the Spanish Ministerio de Ciencia, Innovación y Universidades.Peer reviewe

(farsi - فارسی‎) 2023 تقویم علمی مکتب

El proyecto “Calendario Científico Escolar 2023” ha consistido en la elaboración de un calendario dirigido al alumnado de educación primaria y secundaria obligatoria. Cada día se ha recogido un aniversario científico o tecnológico como, por ejemplo, nacimientos de personas de estos ámbitos o conmemoraciones de hallazgos destacables. Además, el calendario se acompaña de una guía didáctica con orientaciones para el aprovechamiento educativo transversal del calendario en las clases, incluyendo actividades adaptadas a cada rango de edad y al alumnado con necesidades especiales. Se trata de la cuarta edición de este proyecto de divulgación científica.Proyecto FCT-21-17253 de la Fundación Española para la Ciencia y la Tecnología (FECYT); Agencia Estatal de Investigación (España); Ministerio de Ciencia e Innovación; Consejo Superior de Investigaciones Científicas; Universidad de León; Delegación del CSIC en Castilla y León; Instituto de Ganadería de Montaña (IGM, CSIC-ULE); Casa de la Ciència de Valencia (CSIC); Cátedra de Cultura Científica de la Universidad del País Vasco/ Euskal Herriko Unibertsitatea (UPV/EHU); People Help; University of California-Davis; Academia de la Llingua Asturiana; Federación Española de Esperanto; Teagasc; PuraVida Software; Universidad de Zaragoza; Casa Árabe; CSIC Delegació a Catalunya; CCULT.org; Museo Didáctico e Interactivo de Ciencias de la Vega Baja del Segura (MUDIC VBS-CV); Universidad Miguel Hernández; Unidade de Divulgación Científica e Cultural - Universidade da Coruña; Asociación Cultural Nogará Religada .Mujeres con Ciencia; Asociaţia Secular-Umanistă din România; Instituto Geológico y Minero de España (IGME); Centro de Biología Molecular Severo Ochoa (CSIC-UAM); Asociación Española para el Avance de la Ciencia (AEAC); Centro de Investigación del Cáncer (CIC, CSIC-USAL); Discapacitodos; Universitat de les Illes Balears (UIB); Comisión Mujeres y Ciencia de la Sociedad Geológica de España; Institut d’Investigació en Intel.ligéncia Artificial (IIIA-CSIC); Centre for Research in Agricultural Genomics (GRAG, CSIC-UAB-ICREA); Escuela de Estudios Hispano-americanos (CSIC); Institut Botànic de Barcelona (IIB, CSIC-Ajuntament Barcelona); Institut de Ciència de Materials de Barcelona (ICMAB, CSIC); Institut de Ciències del Mar (ICM, CSIC); PRISMA – Asociación para la diversidad afectivo-sexual y de género en ciencia, tecnología e innovación; Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA, CSIC); Círculo Escéptico; Civiencia; Universidad Autónoma de Madrid; Escuela de Estudios Árabes (CSIC); Evento Ciencia; Europa Laica; Universidad de Oviedo; Institut de Microelectrònica de Barcelona - Centre Nacional de Microelectrònica (IMB-CNM, CSIC); Centre d'Estudis Avançats de Blanes (CEAB, CSIC). ePeer reviewe

Scienca lerneja kalendaro 2023 (esperanto)

El proyecto “Calendario Científico Escolar 2023” ha consistido en la elaboración de un calendario dirigido al alumnado de educación primaria y secundaria obligatoria. Cada día se ha recogido un aniversario científico o tecnológico como, por ejemplo, nacimientos de personas de estos ámbitos o conmemoraciones de hallazgos destacables. Además, el calendario se acompaña de una guía didáctica con orientaciones para el aprovechamiento educativo transversal del calendario en las clases, incluyendo actividades adaptadas a cada rango de edad y al alumnado con necesidades especiales. Se trata de la cuarta edición de este proyecto de divulgación científica.Proyecto FCT-21-17253 de la Fundación Española para la Ciencia y la Tecnología (FECYT); Agencia Estatal de Investigación (España); Ministerio de Ciencia e Innovación; Consejo Superior de Investigaciones Científicas; Universidad de León; Delegación del CSIC en Castilla y León; Instituto de Ganadería de Montaña (IGM, CSIC-ULE); Casa de la Ciència de Valencia (CSIC); Cátedra de Cultura Científica de la Universidad del País Vasco/ Euskal Herriko Unibertsitatea (UPV/EHU); People Help; University of California-Davis; Academia de la Llingua Asturiana; Federación Española de Esperanto; Teagasc; PuraVida Software; Universidad de Zaragoza; Casa Árabe; CSIC Delegació a Catalunya; CCULT.org; Museo Didáctico e Interactivo de Ciencias de la Vega Baja del Segura (MUDIC VBS-CV); Universidad Miguel Hernández; Unidade de Divulgación Científica e Cultural - Universidade da Coruña; Asociación Cultural Nogará Religada.Mujeres con Ciencia; Asociaţia Secular-Umanistă din România; Instituto Geológico y Minero de España (IGME); Centro de Biología Molecular Severo Ochoa (CSIC-UAM); Asociación Española para el Avance de la Ciencia (AEAC); Centro de Investigación del Cáncer (CIC, CSIC-USAL); Discapacitodos; Universitat de les Illes Balears (UIB); Comisión Mujeres y Ciencia de la Sociedad Geológica de España; Institut d’Investigació en Intel.ligéncia Artificial (IIIA-CSIC); Centre for Research in Agricultural Genomics (GRAG, CSIC-UAB-ICREA); Escuela de Estudios Hispano-americanos (CSIC); Institut Botànic de Barcelona (IIB, CSIC-Ajuntament Barcelona); Institut de Ciència de Materials de Barcelona (ICMAB, CSIC); Institut de Ciències del Mar (ICM, CSIC); PRISMA – Asociación para la diversidad afectivo-sexual y de género en ciencia, tecnología e innovación; Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA, CSIC); Círculo Escéptico; Civiencia; Universidad Autónoma de Madrid; Escuela de Estudios Árabes (CSIC); Evento Ciencia; Europa Laica; Universidad de Oviedo; Institut de Microelectrònica de Barcelona - Centre Nacional de Microelectrònica (IMB-CNM, CSIC); Centre d'Estudis Avançats de Blanes (CEAB, CSIC).Peer reviewe

Calendário Científico Escolar 2023 (português-BR)

El proyecto “Calendario Científico Escolar 2023” ha consistido en la elaboración de un calendario dirigido al alumnado de educación primaria y secundaria obligatoria. Cada día se ha recogido un aniversario científico o tecnológico como, por ejemplo, nacimientos de personas de estos ámbitos o conmemoraciones de hallazgos destacables. Además, el calendario se acompaña de una guía didáctica con orientaciones para el aprovechamiento educativo transversal del calendario en las clases, incluyendo actividades adaptadas a cada rango de edad y al alumnado con necesidades especiales. Se trata de la cuarta edición de este proyecto de divulgación científica.Proyecto FCT-21-17253 de la Fundación Española para la Ciencia y la Tecnología (FECYT); Agencia Estatal de Investigación (España); Ministerio de Ciencia e Innovación; Consejo Superior de Investigaciones Científicas; Universidad de León; Delegación del CSIC en Castilla y León; Instituto de Ganadería de Montaña (IGM, CSIC-ULE); Casa de la Ciència de Valencia (CSIC); Cátedra de Cultura Científica de la Universidad del País Vasco/ Euskal Herriko Unibertsitatea (UPV/EHU); People Help; University of California-Davis; Academia de la Llingua Asturiana; Federación Española de Esperanto; Teagasc; PuraVida Software; Universidad de Zaragoza; Casa Árabe; CSIC Delegació a Catalunya; CCULT.org; Museo Didáctico e Interactivo de Ciencias de la Vega Baja del Segura (MUDIC VBS-CV); Universidad Miguel Hernández; Unidade de Divulgación Científica e Cultural - Universidade da Coruña; Asociación Cultural Nogará Religada.Mujeres con Ciencia; Asociaţia Secular-Umanistă din România; Instituto Geológico y Minero de España (IGME); Centro de Biología Molecular Severo Ochoa (CSIC-UAM); Asociación Española para el Avance de la Ciencia (AEAC); Centro de Investigación del Cáncer (CIC, CSIC-USAL); Discapacitodos; Universitat de les Illes Balears (UIB); Comisión Mujeres y Ciencia de la Sociedad Geológica de España; Institut d’Investigació en Intel.ligéncia Artificial (IIIA-CSIC); Centre for Research in Agricultural Genomics (GRAG, CSIC-UAB-ICREA); Escuela de Estudios Hispano-americanos (CSIC); Institut Botànic de Barcelona (IIB, CSIC-Ajuntament Barcelona); Institut de Ciència de Materials de Barcelona (ICMAB, CSIC); Institut de Ciències del Mar (ICM, CSIC); PRISMA – Asociación para la diversidad afectivo-sexual y de género en ciencia, tecnología e innovación; Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA, CSIC); Círculo Escéptico; Civiencia; Universidad Autónoma de Madrid; Escuela de Estudios Árabes (CSIC); Evento Ciencia; Europa Laica; Universidad de Oviedo; Institut de Microelectrònica de Barcelona - Centre Nacional de Microelectrònica (IMB-CNM, CSIC); Centre d'Estudis Avançats de Blanes (CEAB, CSIC).Peer reviewe