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Commercially available oxygen scavengers used to prevent lipid autoxidation, microbial growth and enzymatic browning in food products present several issues, which include the usage of metals and their moisture dependence to work properly. We present the synthesis and characterization of a moisture-independent oil-based oxygen scavenging system comprised of linseed oil and silica nanoparticles. The system was synthesized via sol-gel chemistry and was characterized using morphological analysis (SEM, AFM, TEM, and N2 adsorption/desorption), oil-loading analysis (TGA), and surface analysis (ζ-potential and ATR-FTIR). Performance of the system was evaluated through headspace measurements and reproducibility of synthetic procedure was verified using six replicates. Nanoparticles showed the desired spherical shape with a diameter of (122.7 ± 42.7 nm) and mesoporosity (pore diameter = 3.66 ± 0.08 nm), with an encapsulation efficiency of 33.9 ± 1.5% and a highly negative ζ-potential (-56.1 ± 1.2 mV) in basic solution. Performance of the system showed a promising high value for oxygen absorption of 25.8 ± 4.5 mL O2/g of encapsulated oil (8.3 ± 1.5 mL O2/g of nanocapsules) through a moisture independent mechanism, which suggests that the synthesized system can be used as an oxygen scavenger in dry atmosphere conditions.

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In the Anthropocene, plastic pollution is a worldwide concern that must be tackled from different viewpoints, bringing together different areas of science. Microbial transformation of polymers is a broad-spectrum research topic that has become a keystone in the circular economy of fossil-based and biobased plastics. To have an open discussion about these themes, experts in the synthesis of polymers and biodegradation of lignocellulose and plastics convened within the framework of The Transnational Network for Research and Innovation in Microbial Biodiversity, Enzymes Technology and Polymer Science (MENZYPOL-NET), which was recently created by early-stage scientists from Colombia and Germany. In this context, the international workshop "Microbial Synthesis and Degradation of Polymers: Toward a Sustainable Bioeconomy" was held on 27 September 2021 via Zoom. The workshop was divided into two sections, and questions were raised for discussion with panelists and expert guests. Several key points and relevant perspectives were delivered, mainly related to (i) the microbial evolution driven by plastic pollution; (ii) the relevance of and interplay between polymer structure/composition, enzymatic mechanisms, and assessment methods in plastic biodegradation; (iii) the recycling and valorization of plastic waste; (iv) engineered plastic-degrading enzymes; (v) the impact of (micro)plastics on environmental microbiomes; (vi) the isolation of plastic-degrading (PD) microbes and design of PD microbial consortia; and (vii) the synthesis and applications of biobased plastics. Finally, research priorities from these key points were identified within the microbial, enzyme, and polymer sciences.

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Introducción: Las fracturas de pelvis se asocian frecuentemente a un trauma de alta energía. La tasa de mortalidad varía del 5% al 46%. El objetivo de este estudio fue explorar si las variables analizadas se asociaron con el resultado final del tratamiento de las fracturas de pelvis APCII (AO/OTA: 61B2.3). materiales y métodos:Se evaluó a 23 de 79 pacientes luego de aplicarles los criterios de selección. Las fracturas fueron clasificadas, según Young y Burgess, en una radiografía panorámica de pelvis, de entrada y de salida, y tomografía computarizada. Se evaluó el resultado clínico según la escala funcional de Majeed. Las variables evaluadas fueron: tratamiento en la urgencia, lesiones asociadas, días de espera hasta la cirugía, fijación utilizada, reducción posquirúrgica inmediata, infección del sitio quirúrgico. Resultados: No se halló una diferencia estadísticamente significativa entre el tipo de tratamiento realizado en la urgencia, las lesiones asociadas, los días de espera hasta la cirugía y el tipo de fijación, con el resultado final a largo plazo. Los pacientes que tuvieron una reducción posoperatoria inmediata <1 cm y los que no sufrieron una infección del sitio quirúrgico obtuvieron mejores resultados funcionales, de manera estadísticamente significativa. Conclusión: Las variables calidad de la reducción posquirúrgica inmediata e infección del sitio quirúrgico en pacientes con fractura de pelvis APCII se asocian directamente con los resultados funcional y clínico a largo plazo. Nivel de Evidencia: IV

Introduction: Pelvic fractures are frequently associated with high-energy trauma. Mortality varies from 5%-46%. In these patients, the factors related to poor outcomes are still controversial. Purpose: To explore if the variables analyzed were related with the long term outcomes of the treatment of an anterior-posterior compression type II pelvic fracture (APCII; AO/OTA: 61B2.3). Materials and methods: 79 cases were analyzed and 23 patients remained for evaluation according to inclusion and exclusion criteria. Pelvic radiographs (anteroposterior, inlet and outlet) and CT-scans were evaluated. The Young & Burgess classification was used to define the fracture pattern and the Majeed Score for clinical outcomes. Variables analyzed: emergency treatment, associated injuries, delay for definitive fixation, method of fixation, quality of immediate postoperative reduction and surgical site infection. Results: We did not find any statistical relation between the type of emergency treatment, associated injuries, delay for definitive fixation, method of fixation, and the long-term clinical outcome. Patients who had an immediate postoperative reduction of less than 1 cm and those who did not have a surgical site infection obtained better functional outcomes (statistically significant). Conclusion: The quality variables of immediate postoperative reduction and surgical site infection in patients with APCII pelvic fracture had a direct relation with long-term functional and clinical outcomes. Level of Evidence: IV

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This research reports the influence of polar monomer contents in ethylene vinyl acetate copolymer (EVA) and ethylene vinyl alcohol copolymer (EVOH) on the morphology, mechanical and barrier properties of polypropylene/ethylene copolymer (PP) reinforced with organically modified montmorillonite (MMT). PP/EVA and PP/EVOH (75/25 wt %) blends were reinforced with 3 wt % MMT in an internal mixer system. Samples were compression-molded into films of 300µ µm. The structural characterization was made using X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), the mechanical properties were obtained by tension tests and the barrier properties by oxygen transmission rate (OTR). XRD patterns showed a combination of intercalated/exfoliated morphologies for the MMT, with higher d-001 interplanar distance increments for the blends with higher content of polar functional groups. SEM and TEM micrographs complement the results of the XRD analysis and show differences in the morphologies depending on the miscibility of the polyolefin and the polar monomer copolymer. Mechanical properties and oxygen permeability of composites exhibited a higher improvement, by the addition of MMT, for higher intermolecular interactions and most miscible polymeric system of the EVA. These results show that the higher the number of interactions, given by the VA or OH polar functional groups, the morphology and the miscibility between polyolefin and copolymer imply dispersion improvements of the nanocomposites and, in consequence, a higher improvement on the mechanical and barrier properties of the composite material.

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RESUMEN El mercado de productos naturales, a nivel alimenticio, medicinal e industrial, se ha incrementado notablemente, promoviendo la innovación e investigación y el uso de materias primas vegetales y animales. La presente investigación tuvo como objetivo diseñar un néctar, con una combinación de matrices de frutas y de vegetales, como uva, espinaca, mora, agraz, yacón, enriquecida con cápsulas de Aloe vera y vitamina C. Se plantearon tres formulaciones, variando la cantidad de ingredientes en la mezcla; se seleccionó el tratamiento más aceptable, mediante evaluación sensorial en panel no entrenado. Todos los néctares tuvieron una buena aceptación organoléptica; no obstante, el 50% de los panelistas mostraron preferencias por el tratamiento 1, que contenía 13% de uva, 4% de espinaca, 3% de agraz y mora, 2% de yacón; el porcentaje restante correspondió a la cantidad de agua y azúcar empleada en la formulación. Al tratamiento con mayor aceptación (T1), se le analizaron los atributos físico químicos, mostrando un pH de 2,96, 12,11°Brix, color, olor y apariencia normales y estables; asimismo, se evaluó la presencia de bacterias mesófilas, hongos y levaduras, E. coli y Salmonella. Con el fin de enriquecer el producto, se elaboraron cápsulas de A. vera y vitamina C, para ser incorporadas en el néctar. Este tipo de producto promueve el consumo de frutas y de vegetales en alimentos procesados de uso frecuente, como los néctares.

ABSTRACT The market of natural products at a nutritional, medicinal and industrial level, has increased remarkably, promoting innovation and research and the use of vegetable and animal raw materials. The objective of this research was to design a nectar, with a combination of fruit and vegetable matrices such as grape, spinach, blackberry, blueberry, yacon, enriched with Aloe vera capsules and vitamin C. Three formulations were proposed varying the number of ingredients in the mixture; the most acceptable treatment was selected through sensory evaluation in an untrained panel. All the nectars had a good organoleptic acceptance, however, 50% of the panelists showed preferences for the treatment 1, it contained 13% of grape, 4% of spinach, 3% of blueberry and blackberry, 2% of yacon, the remaining percentage corresponded to the amount of water and sugar used in the formulation. To the treatment with greater acceptance (T1) the physical-chemical attributes were analyzed, showing a pH of 2.96; 12.11°Brix, color, smell and appearance normal and stable, likewise the presence of mesophilic bacteria, fungi and yeasts, E. coli and Salmonella was evaluated. In order to enrich the product, capsules of A. vera and vitamin C were prepared to be incorporated into the nectar. This type of product promotes the consumption of fruits and vegetables in processed foods of frequent use such as nectars.