Determination of microbiological and sensory parameters of fish fillets with propolis preserved under refrigeration

ABSTRACT Objective: To determine the ability of propolis preservative cachama fillets during refrigerated storage. Materials and method. Ethanol extracts of propolis (EEP) were used in cachama fillets. The treatments included: i) 96% ethanol alcohol as the control; ii) 0.8% EEP; iii) 1.2% EEP; and iv) liquid smoke. A in vitro analysis was used to determine the inhibitory effect of propolis on Staphylococcus aureus, Escherichia coli, Salmonella sp. and Clostridium sp. and on the fish matrix to determine the mesophiles, psychrotrophiles, total coliforms, fecal coliforms, sulphite reducing spores and the presence of Salmonella. Results. The results of the in vitro analysis demonstrated the control that the EEP had over the evaluated microorganisms without presenting significant differences between the different concentrations (p>0.05). The analyses of the fish fillet matrix presented acceptable contents for the evaluated microorganisms in the treatments with EEP. A different situation was seen in the treatment with liquid smoke and the control, which had samples that where rejected after 20 days of storage. The sensory analysis showed acceptance for the samples with EEP until the end of the storage period but low marks for the treatment with liquid smoke and the control. Conclusions. The EEP used in this study could be effective for the control of Gram positive bacteria and some Gram negative bacteria that are present in cachama fillets; and could be an alternative to the use of chemical preservatives

Novel Fluorescent Labeled Octasilsesquioxanes Nanohybrids as Potential Materials for Latent Fingerprinting Detection

The recent demand for fluorescent labeled materials (FLMs) in forensic security concepts such as latent fingerprints (LFs) that encodes information for anti-counterfeiting and encryption of confidential data makes necessary the development of building new and innovative materials. Here, novel FLMs based on Polyhedral Oligomeric Silsesquioxanes (POSS) functionalized with fluorophores via “click” reactions have been successfully synthesized and fully characterized. A comprehensive study of their photophysical properties has displayed large Stokes’s shift together with good photostability in all cases, fulfilling the fundamental requisites for any legible LF detection on various surfaces. The excellent performance of the hetero-bifunctional FLM in the visualization of LF is emphasized by their legibility, selectivity, sensitivity and temporal photostability. In this study, development mechanisms have been proposed and the overall concept constitute a novel approach for vis-à-vis forensic investigations to trace an individual’s identity.Alexander von Humboldt FoundationGeneralitat ValencianaUniversität RegensburgUniversidad de La LagunaMinisterio de Ciencia, Innovación y Universidade

Cutting down on the grog: the crystallisation of Neolithic ceramic traditions at Cova d’En Pardo (Alicante, Spain) and cultural change in the western Mediterranean basin (mid-6th and 5th millennia cal. BC)

This paper presents the characterisation of 48 ceramic samples from Cova d’En Pardo (Alicante, Spain). Provenance and technology analysis are carried out on materials dated back to different Early and Middle Neolithic cultural phases, including pioneer and Epicardial levels, poorly known in the area. The techniques employed are optical petrography and scanning electron microscope. Two main fabrics were identified, characterised by the heavy presence of temper (grog and calcite), along with five minor petrographic classes, including two imports, one of them probably from southern Iberia. The comparison among occupational phases within the site reveals changes along the stratigraphic series, especially during the transition from the 6th to 5th millennia cal. BC, which is reflected in temper choice. Evidence from the earliest occupation of the site also agrees with the picture of discontinuity previously observed on nearby contexts between pioneer and traditional Cardial ceramic technology, which might be connected to neolithization routes. Firing technology is characterised by the occurrence of microstructure gradients and signs of fast heating rates.Sample preparation and analyses were funded by the projects NEOMEDPOT (Marie Skłodowska-Curie program, European Commission, grant number 659466) and Espacios sociales y espacios de frontera durante el calcolítico y la Edad del Bronce en el Levante de la península Ibérica (HAR2016-76586-P, Ministerio de Economía y Competitividad and FEDER). Miguel del Pino is a postdoctoral researcher within the Viera y Clavijo program, funded by the Universidad de Las Palmas de Gran Canaria (Spain). The initial draft of the paper was finished while a postdoctoral researcher within the APOSTD program funded by the Generalitat Valenciana and FEDER funds (Spain)

Recent applications of biphotonic processes in organic synthesis

Currently, evolution of chemical transformations by visible light irradiation is highly desirable from cost, safety, availability, and environmental friendliness points of view. Besides, activation of less reactive substrates under very mild conditions becomes one of the most challenging tasks in organic synthesis. However, the insufficient energy provided by one photon of visible light for their activation definitely makes necessary the development of new protocols together with the design of new photocatalytic systems to overcome this limitation. In this context, the implementation of biphotonic processes has been found to be a solution for these drawbacks. This new mechanistic paradigm which combines light upconversion processes with energy/electron transfers holds great potential for high energy demanding bond activations, expanding the accessible reactivity window. Here, we wish to highlight the recent applications of biphotonic processes in organic synthesis.Generalitat ValencianaGobierno de Españ

Highly efficient latent fingerprint detection by eight-dansyl-functionalized octasilsesquioxane nanohybrids

The largely demand in continued security issues makes necessary the development of novel materials with outstanding properties to improve the current detection techniques. In this context, latent fingerprint (LF) by fluorescent labeled materials (FLM) is one of the most attractive personnel identification methodologies. Here, two FLM based on polyhedral oligomeric silsesquioxane (POSS) nanohybrids labeled with dansyl chromophores have been synthesized and fully characterized. Their photophysical properties have confirmed that these materials clearly possess the prime qualifications as suitable LF sensing platforms. In fact, they adequately detect LFs on glassy surface with excellence legibility.Alexander von Humboldt FoundationGeneralitat ValencianaUniversit¨at RegensburgMinisterio de Ciencia, Innovación y Universidade

Airborne Cupressaceae Pollen and Its Major Allergen, Cup a 1, in Urban Green Areas of Southern Iberian Peninsula

Cupressaceae pollen is responsible for winter respiratory allergies in the Mediterranean area. Pollen grains of this diverse family share the same characteristics under light microscopy. Consequently, the partial contribution of each Cupressaceae species to the airborne pollen spectrum cannot be determined with conventional aerobiological methods. Studies on major aeroallergens offer better information on the allergic sensitization and appearance of symptoms in patients sensitized to airborne pollen and spores. Our aim was to determine if airborne Cupressaceae pollen concentrations correspond to aerodynamics of the major allergen of Cupressus (Cup a 1), as well as the aeroallergen correlation with different-sized particles. The air was sampled in two cities of Southern Spain (Granada and Córdoba) using the Hirst-type volumetric sampler for airborne pollen detection during 2006 to 2008 and the Andersen Cascade Impactor for aeroallergen detection during the main pollination period of Cupressaceae in the same period. The samples were analyzed by the methodology proposed by the Spanish Aerobiology Network (REA), the minimum requirements of the European Aeroallergen Society (EAS) for pollen, and by ELISA immunoassay to detect airborne Cup a 1. The distribution patterns of airborne Cupressaceae pollen and Cup a 1 were observed throughout the sampling period, although with some irregular oscillations. Cupressaceae pollen and Cup a 1 showed positive and significant correlation during the period of maximum concentrations (January to March). However, the results of this study showed that the period of exposure of aeroallergens depends on the Cupressus species and their abundance in cities. According to the allergy potential obtained, species like C. arizonica could release more allergens than other species like C. sempervirens.Ministry of Science and Technology I + D + I of Spain CGL2006-1648-CO3-02Andalusian Government RNM 011

Electrochemical behaviour of Iron in chlorinated alkaline media: the effect of slurries from granite processing

Porriño is a well known zone of quarry and stone working of the SW of Galicia, Spain. In granite's working processes 3 <FONT FACE=Symbol>&times;</FONT> 10(5) ton year-1 of granite powder are generated in this area, causing an important environmental problem. This dust has proved to be an efficient addition to high-strength concrete to improve mechanical properties. Nevertheless, no works have been published concerning the effect of this admixture in the passivation of steel reinforcements. The objective of the present work is to analyze the electrochemical behaviour of iron and carbon steel electrodes in alkaline solutions resulting from these slurries. The growth and evolution of the passive layers formed on the tested electrodes are studied by Cyclic Voltammetry and Electrochemical Impedance Spectroscopy. Scanning Electron Microscopy and X-ray powder Diffraction have been used for the morphological and chemical characterisation of the generated passive films. The effect of the presence of Cl- ions is also considered

Desarrollo y validación de un método multiresiduo para el análisis de plaguicidas en miel por UFLC-MS

Se desarrolló un método para la determinación de residuos de plaguicidas en miel de abejas mediante cromatografía líquida ultra rápida acoplada a espectrometría de masas (cuádruplo sencillo). Se partió del método QuEChERS, evaluando las siguientes variables: (i) cantidad de muestra, (ii) tipo de sal para el control de pH, (iii) valor de pH del buffer y (iv) mezclas de limpieza. Adicionalmente y con el propósito de demostrar la confiabilidad del método, se evaluaron diferentes parámetros como exactitud, límites de detección y cuantificación, linealidad y selectividad. Los resultados mostraron que, mediante las modificaciones realizadas, se logró obtener un método más selectivo y se mejoró la exactitud de 19 plaguicidas respecto al método QuEChERS original. Por otro lado, mediante el proceso de validación, se encontró que el método es apto para el análisis de 50 plaguicidas (de 56 que se emplearon). Se obtuvieron porcentajes de recuperación entre el 70 y 120% y coeficientes de variación inferiores al 15%.A method for the determination of pesticide residues in honey by ultra fast liquid chromatography coupled with mass spectrometry was developed. For this purpose, different variations of the QuECHERS method were performed: (i) amount of sample, (ii) type of salt to control pH, (iii) buffer pH, and (iv) different mixtures for cleaning-up. In addition, to demonstrate that the method is reliable, different validation parameters were studied: accuracy, limits of detection and quantification, linearity and selectivity. The results showed that by means of the changes introduced it was possible to get a more selective method that improves the accuracy of about 19 pesticides selected from the original method. It was found that the method is suitable for the analysis of 50 pesticides, out of 56. Furthermore, with the developed method recoveries between 70 and 120% and relative standard deviation below 15% were found

Evaluation of the physicochemical and functional properties of Colombian bee pollen

ABSTRACT Objective. To establish current knowledge about Colombian bee-pollen from a point of view nutritional and functional, contributing towards creating national technical standards and the identification of chemical differentiation factors for further researches. Material and methods. One hundred ninety-six samples of dried bee pollen were collected in the center region of Colombia known as Cundi-boyacense high plateau, where nearly 90% of total bee pollen production is concentrated in this country. Performed physicochemical analyses in this study were: moisture, pH, acidity, ash, carbohydrates, lipids, proteins, dietary fiber, fatty acid profile and mineral elements. Results. Bee pollen from this region had 7.7±5.2 g/100 g moisture content, and a following centesimal composition based on dry matter: ashes 2.5±0.4 g; lipids 6.90±3.5 g; proteins 23.8±3.2 g and total dietary fiber 14.5±3.5 g. The most abundant fatty acids were α-linolenic, palmitic and linoleic. Carbohydrates were the main components and fructose and glucose the most concentrated sugars. The predominant minerals assessed here were potassium, calcium and magnesium. The results were also discussed in terms of the characteristics found in Colombian bee-pollen in comparison to international regulations and findings for other varieties of commercial bee-pollen from eight different countries. Conclusions. The results found in this study suggest that bee-pollen may be used as a dietary supplement and agree with bibliographical reports and international regulations. Such characterization will enable to be proposed technical standards in line with Colombian bee-pollen properties and it is expected to improve marketing and production chain conditions