La investigación universitaria impulsa la economía rural

La Voz de Galicia, 13 de octubre de 2015

El CIA desarrolló en 5 años 22 proyectos agroambientales y alimentarios.

La investigación universitaria se está convirtiendo en un elemento dinamizador del desarrollo rural sostenible, favoreciendo la revalorización de los recursos del territorio por su contribución a las diferentes actividades de las industrias agroalimentarias.

Esta repercusión socioeconómica en una provincia desangrada demográficamente es una de las consideraciones de la última memoria del Centro de Investigacións Agroambientais e Alimentarias (CIA), una agrupación estratégica de investigación universitaria -la única gallega en un campus periférico- que cuenta con financiación de la Consellería de Cultura, Educación e Ordenación Universitaria.

De las ocho agrupaciones estratégicas de investigación con financiación autonómica, tres versan sobre nuevas tecnologías; dos sobre medicina; una sobre química y otra sobre el mar. La ourensana, dirigida por Jesús Simal, es la única que vincula los ámbitos ambiental, agrario y alimentario en la cadena de producción de alimentos. Es en ese terreno en el que está llamada a ser «unha peza chave para o futuro exitoso do sector agroalimentario» y un apoyo para proyectos económicos de éxito que asienten población en la geografía rural gallega.

Constituido por grupos de investigación del CITI (Centro de Investigación, Transferencia e Innovación, de la Tecnópole), la Facultad de Ciencias de Ourense y la Facultad de Bioloxía de Vigo, el CIA reúne a varias decenas de investigadores. Trabajan en torno a tres ejes: la producción primaria sostenible, el desarrollo de nuevos productos y la calidad y seguridad alimentaria.

Su participación en programas de formación y la investigación cooperativa y multidisciplinar son dos de sus fortalezas. Incrementar la transferencia de los resultados de sus investigaciones al sector público y al privado, y aumentar su presencia en proyectos internacionales, son sus retos.

Colaboración con empresas

La repercusión de sus investigaciones queda patente con los programas de colaboración con 38 empresas alimentarias con interés en productos como aceite, agua, pescado, aves, galletas, bebidas alcohólicas, lácteos, carnes, platos preparados, pan o surimi. Esa colaboración con el sector empresarial ha dado lugar a numerosos proyectos de investigación y ha supuesto una fuente de financiación a mayores, ya que el 34% de los fondos del centro entre 2012 y 2014 procedía de firmas privadas.

Los acuerdos de transferencia y explotación de las investigaciones han dado resultados concretos, como el diseño de procedimientos para obtener aguardiente de castañas y el de un extracto gelificable de proteínas a partir del agua de cocción de pescado, así como la composición para aumentar el contenido proteico en carne de pescado y el procedimiento para su aplicación.

Manufacture of furfural in biphasic media made up of an ionic liquid and a co-solvent

Industrial Crops and Products, 77, 163-166 (2015)

DOI: 10.1016/j.indcrop.2015.08.048

Xylose was converted into furfural operating in a medium containing the acidic ionic liquid (AIL) 1-butyl-3-methylimidazolium hydrogen sulfate, in the presence of toluene as a co-solvent. No catalytic species different from the AIL were needed for furfural production from xylose. Operating at 100-140. °C for 15-480. min in media containing 10. g xylose/100. g AIL and 2-4. g toluene/g (AIL. +. xylose), most furfural generated in the AIL phase was transferred to the co-solvent, limiting the losses caused by undesired side reactions. Operating under optimal conditions (140. °C for 240. min using 4.4. g toluene/g initial AIL phase), xylose was almost completely consumed, and furfural was obtained at 73.8% of the stoichiometric yield.

Agricultural residue valorization using a hydrothermal process for second generation bioethanol and oligosaccharides production

Bioresource Technology, 191, 263-270 (2015)

DOI: 10.1016/j.biortech.2015.05.035

In the present work, the hydrothermal valorization of an abundant agricultural residue has been studied in order to look for high added value applications by means of hydrothermal pretreatment followed by fed-batch simultaneous saccharification and fermentation, to obtain oligomers and sugars from autohydrolysis liquors and bioethanol from the solid phase. Non-isothermal autohydrolysis was applied to barley straw, leading to a solid phase with about a 90% of glucan and lignin and a liquid phase with up to 168gkg-1 raw material valuable hemicellulose-derived compounds. The solid phase showed a high enzymatic susceptibility (up to 95%). It was employed in the optimization study of the fed-batch simultaneous saccharification and fermentation, carried out at high solids loading, led up to 52gethanol/L (6.5% v/v). 

Simple and efficient furfural production from xylose in media containing 1-butyl-3-methylimidazolium hydrogen sulfate

Industrial and Engineering Chemistry Research, 54, 8368-8373 (2015)

DOI: 10.1021/acs.iecr.5b01771

The acidic 1-butyl-3-methylimidazolium hydrogen sulfate ([bmim][HSO4]) ionic liquid was explored as both a reaction medium and a catalyst in the furfural production from xylose. Preliminary experiments were carried out at 100-140 °C for 15-480 min in systems containing just xylose dissolved in [bmim][HSO4] in the absence of externally added catalysts. More than 95% xylose conversion was achieved when operating at 120 or 140 °C for 300 and 90 min, respectively; but just 36.7% of the initial xylose was converted to furfural. Operation in biphasic reaction systems (in the presence of toluene, methyl-isobutyl ketone or dioxane as extraction solvents) at 140 °C under selected conditions resulted in improved furfural production (73.8%, 80.3%, and 82.2% xylose conversion to furfural for the cited extraction solvents, respectively). 

Biomass, sugar, and bioethanol potential of sweet corn

GCB Bioenergy, 7, 153-160 (2015)

DOI: 10.1111/gcbb.12136

Sweet corn is a widely distributed crop that generates agricultural waste without significant commercial value. In this study, we show that sweet corn varieties produce large amounts of residual biomass (10 t ha-1) with high content of soluble sugars (25% of dry matter) in a short growing season (3 months). The potential ethanol production from structural and soluble sugars extracted from sweet corn stover reached up to 4400 l ha-1 in the most productive hybrids, 33% of which (1500 l ha-1) were obtained by direct fermentation of free sugars. We found wide genetic variation for biomass yield and soluble sugars content suggesting that those traits can be included as complementary traits in sweet corn breeding programs. Dual-purpose sweet corn hybrids can have an added value for the farmers contributing to energy generation without affecting food supply or the environment.

Barley straw (Hordeum vulgare) as a supplementary raw material for Eucalyptus camaldulensis and Pinus sylvestris kraft pulp in the paper industry

BioResources, 10 (2) 3682-3693 (2015)

DOI: 10.15376/biores.10.2.3682-3693

The present study shows that barley straw (Hordeum vulgare) can be a supplementary raw material of softwoods and hardwoods such as Pinus sylvestris and Eucalyptus camaldulensis, respectively, for the production of cellulose and paper, reducing an agricultural residue that has no added value. Barley straw has a lower content of cellulose at 36.4% than P. sylvestris and E. camaldulensis, but it contains a lower quantity of lignin, 15.9%. After pulping with soda anthraquinone (AQ), high contents of cellulose (56.5 to 67.5%) and holocellulose (>80%) were attained. Paper sheet properties were able to reach, and even improve upon, those of wood species (Pinus and Eucalyptus) pulped with kraft. Better values of total yield (56.5%), Kappa number (8.9), and ISO brightness (36.4%), were attained for paper sheets from barley straw pulp versus E. camaldulensis and P. sylvestris, respectively, and comparable values for viscosity, tensile, and burst index were obtained.

A new method for determining the sources of airborne particles

Journal of Environmental Management

DOI: 10.1016/j.jenvman.2015.03.037

Air quality is a major issue for humans owing to the fact that the content of particles in the atmosphere has multiple implications for life quality, ecosystem dynamics and environment. Scientists are therefore particularly interested in discovering the origin of airborne particles. A new method has been developed to model the relationship between the emission surface and the total amount of airborne particles at a given distance, employing olive pollen and olive groves as examples. A third-degree polynomial relationship between the air particles at a particular point and the distance from the source was observed, signifying that the nearest area to a point is not that which is most correlated with its air features. This work allows the origin of airborne particles to be discovered and could be implemented in different disciplines related to atmospheric aerosol, thus providing a new approach with which to discover the dynamics of airborne particles.

Voltammetric analysis of mancozeb and its degradation product ethylenethiourea

Journal of Electroanalytical Chemistry

doi:10.1016/j.jelechem.2015.08.030

The purpose of this work was to develop a reliable alternative method for the determination of the dithiocarbamate pesticide mancozeb (MCZ) in formulations. Furthermore, a method for the analysis of MCZ's major degradation product, ethylenethiourea (ETU), was also proposed. Cyclic voltammetry was used to characterize the electrochemical behaviour of MCZ and ETU, and square-wave adsorptive stripping voltammetry (SWAdSV) was employed for MCZ quantification in commercial formulations.

It was found that both MCZ and ETU are irreversibly reduced (−0.6 V and −0.5 V vs Ag/AgCl, respectively) at the surface of a glassy carbon electrode in a mainly diffusion-controlled processes, presenting maximum peak current intensities at pH 7.0 (in phosphate buffered saline electrolyte).

Several parameters of the SWAdSV technique were optimized and linear relationships between concentration and peak current intensity were established between 10–90 μmol L-1 and 10–110 μmol L-1 for MCZ and ETU, respectively. The limits of detection were 7.0 μmol L-1 for MCZ and 7.8 μmol L-1 for ETU. The optimized method for MCZ was successfully applied to the quantification of this pesticide in two commercial formulations. The developed procedures provided accurate and precise results and could be interesting alternatives to the established methods for quality control of the studied products, as well as for analysis of MCZ and ETU in environmental samples.

High-throughput HPLC–MS/MS determination of the persistence of neonicotinoid insecticide residues of regulatory interest in dietary bee pollen

Analytical and Bioanalytical Chemistry

DOI 10.1007/s00216-015-8870-4

The aim of this work is the development of a simple, fast, quantitative, and economic method for the determination of neonicotinoid insecticide residues in dietary bee pollen. Several parameters of the method, such as extraction solvent, extraction time, and solid-phase extraction sorbents for purification [silica, C18, primary–secondary amine (PSA), and Envi-Carb II/PSA], were studied. The final proposed method based on solid–liquid extraction with hexane, cleanup with Supelclean™ Envi-Carb II/PSA cartridges, and subsequent analysis by high-performance liquid chromatography with tandem mass spectrometry was validated and applied to the analysis of commercial bee pollen samples from different geographical zones. Method performance was assessed by the evaluation of several quality parameters of the method, such as recovery values, repeatability, reproducibility, linearity, and limits of detection and quantification. Matrix effects on the chromatographic signal were also studied. The quality parameters of the method were equivalent to or better than those obtained with previously published methods, with recoveries between 81 and 99 % and repeatabilities lower than 8.8 %. The detection and quantification limits were in the ranges 0.2-2.2 μg kg-1 and 0.4-4.3 μg kg-1, respectively.

Thirty-four identifiable airborne fungal spores in Havana, Cuba

Annals of Agricultural and Environmental Medicine

DOI: 10.5604/12321966.1152068

The airborne fungal spore content in Havana, Cuba, collected by means a non-viable volumetric methodology, was studied from November 2010 – October 2011. The study, from a qualitative point of view, allowed the characterization of 29 genera and 5 fungal types, described following the Saccardo´s morphotypes, as well as their morphobiometrical characteristics. In the amerospores morphotype, the conidia of 7 genera (with ascospores, basidiospores and uredospores) and 5 fungal types were included. Among phragmospores morphotype, the ascospores and conidia of 12 different genera were identified. The dictyospores morphotype only included conidial forms from 6 genera. Finally, the less frequent morphotypes were staurospores, didymospores and distosepted spores. In general, the main worldwide spread mitosporic fungi also predominated in the Havana atmosphere, accompanied by some ascospores and basidiospores. Cladosporium cladosporioides type was the most abundant with a total of 148,717 spores, followed by Leptosphaeria, Coprinus and the Aspergillus-Penicillium type spores, all of them with total values ranging from 20,591 – 16,392 spores. The higher monthly concentrations were registered in January (31,663 spores) and the lowest in December (7,314 spores). Generally, the average quantity of spores recorded during the months of the dry season (20,599 spores) was higher compared with that observed during the rainy season (17,460 spores).

Challenges in Relating Concentrations of Aromas and Tastes with Flavour Features of Foods

Critical Reviews in Food Science and Nutrition

DOI: 10.1080/10408398.2015.1048775

Flavour sensations in food are highly influenced by the aroma and taste compounds. Reviewing the extensive literature of recent years in this field has shown that the reconstitution of flavour based on aroma and taste compounds poses numerous problems. These are of different nature and include among others (a) chemical transformations among these compounds, (b) changes in the concentrations of the compounds responsible for the perceived flavour, (c) interactions among the chemical compounds that enhance or reduce a specific flavour sensation, and finally, (d) the complexity of the different food matrices and its influence in the flavour perception. Another difficulty that flavour scientists must face is how to properly model and visualize the complex relationships existing between the chemical composition of foods and the flavour perception. These problems have repercussions on the reconstitution of the flavour signature of food based on the natural concentrations of its key aroma and taste compounds. Therefore, the main aim of this review is to deal with all these issues to propose potential solutions for a robust transformation in a science-based quality approach.

Linear Polyethers as Additives for AOT-Based Microemulsions: Prediction of Percolation Temperature Changes Using Artificial Neural Networks

Tenside Surfactants Detergents: 52 (2015) 264-270.
doi: 10.3139/113.110374

 

Predictive models based on artificial neural networks have been developed for the percolation threshold of AOT based microemulsions with addition of either glymes or polyethylene glycols. Models have been built according to the multilayer perceptron architecture, with five input variables (concentration, molecular mass, log P, number of C and O of the additive). Best model for glymes has a topology of five input neurons, five neurons in a single hidden layer and one output neuron. Polyethylene glycol model's architecture consists in five input neurons, three hidden layers with eight neurons in both first two and five in the last, and a neuron in the last output layer. All of them have a good predictive power according to several quality parameters.

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Higher peroxidase activity, leaf nutrient contents and carbon isotope composition changes in Arabidopsis thaliana are related to rutin stress

Journal of Plant Physiology

DOI: 10.1016/j.jplph.2014.05.009

Rutin, a plant secondary metabolite that is used in cosmetics and food additive and has known medicinal properties, protects plants from UV-B radiation and diseases. Rutin has been suggested to have potential in weed management, but its mode of action at physiological level is unknown. Here, we report the biochemical, physiological and oxidative response of Arabidopsis thaliana to rutin at micromolar concentrations. It was found that fresh weight; leaf mineral contents (nitrogen, sodium, potassium, copper and aluminum) were decreased following 1 week exposure to rutin. Arabidopsis roots generate significant amounts of reactive oxygen species after rutin treatment, consequently increasing membrane lipid peroxidation, decreasing leaf Ca2+, Mg2+, Zn2+, Fe2+ contents and losing root viability. Carbon isotope composition in A. thaliana leaves was less negative after rutin application than the control. Carbon isotope discrimination values were decreased following rutin treatment, with the highest reduction compared to the control at 750μM rutin. Rutin also inhibited the ratio of CO2 from leaf to air (ci/ca) at all concentrations. Total protein contents in A. thaliana leaves were decreased following rutin treatment. It was concluded carbon isotope discrimination coincided with protein degradation, increase lipid peroxidation and a decrease in ci/ca values may be the primary action site of rutin. The present results suggest that rutin possesses allelopathic potential and could be used as a candidate to develop environment friendly natural herbicide.

Modeling the batch bacteriocin production system by lactic acid bacteria by using modified three-dimensional Lotka-Volterra equations

Biochemical Engineering Journal

DOI: 10.1016/j.bej.2014.04.010

Different batch cultures of Lactococcus lactis CECT 539, a nisin-producing strain, were carried out in culture media prepared with whey and mussel processing wastes. From these cultures, a reasonable system of differential equations, similar to the three-dimensional Lotka-Volterra two predators-one prey model, was set up to describe, for the first time, the relationship between the absolute rates of growth, pH drop and nisin production.Thus, the nisin production system was described as a three-species (pH, biomass and nisin) ecosystem. In this case, both nisin and biomass production were considered as two pH-dependent species that compete for the nitrogen source. Excellent agreement (R2 values ≥0.9885) resulted between model predictions and the experimental data, and significant values for all the model parameters were obtained. The developed model was demonstrated (R2 values ≥0.9874) for five batch cultivations of the strains L. lactis CECT 539 in MRS broth and Lactobacillus sakei LB 706 (sakacin A producer), Pediococcus acidilactici LB42-923 (pediocin AcH producer), L. lactis ATCC 11454 (nisin producer) and Leuconostoc carnosum Lm1 (leuconocin Lcm1 producer) in TGE broth. These results suggest that the batch bacteriocin production system in these culture media can be successfully described by using the Lotka-Volterra approach.

Assessment of potential probiotic properties and multiple bacteriocin encoding-genes of the technological performing strain Enterococcus faecium MMRA

Food Control

DOI: 10.1016/j.foodcont.2013.09.044

In the present study, Enterococcus faecium MMRA, a safety and technological performing strain, previously isolated from a well-known fermented dairy product of Tunisia, was evaluated for certain properties relevant to probiotic including acid and bile tolerance, gastrointestinal juice resistance and adhesive properties. Acidic pH (2.0-5.0) and bile salt concentrations of 0.3% were used as stress conditions. The adhesive properties were assessed by determination of bacterial hydrophobicity. The strain MMRA showed interesting features such as high tolerance to gastrointestinal tract transit, an extremely high survival rates under stress caused by acidic pHs or bile salts, and a high adhesive potential linked to the elevated percentage of hydrophobicity. Furthermore, the genome of this strain was examined for the occurrence of known enterocin (enterococcal bacteriocins) genes by means of specific PCR assays and this study revealed the genes coding for enterocins A, B, P and X. Although the joint production of these bacteriocins has not been verified, producers of multiple enterocins could have a great technological potential as protective and/or probiotic cultures in the food industry. The results suggested that E.faecium MMRA should be considered as a potential probiotic which meets the criteria to enhance healthy attributes of fermented dairy product besides both of hygienic and sensory aspects.

Cr(VI) sorption/desorption on pine sawdust and oak wood ash

International Journal of Environmental Research and Public Health

DOI: 10.3390/ijerph120808849

The objective of this work was to study Cr(VI) sorption/desorption on two by-products from the wood industry: pine sawdust and oak wood ash. The retention/release experiments were carried out using standard batch-type trials. In the sorption-phase experiments, pine sawdust showed 23% sorption when a concentration of 100 mg Cr(VI)·L-1 was added, whereas sorption on oak wood ash was 17%. In the desorption-phase, chromium release was clearly higher from pine sawdust than from oak wood ash (98% and 66%, respectively). Sorption curves were well fitted to the Freundlich and Lineal models. In view of the results, both materials can be considered of very limited value to remove Cr from polluted soil and water, which can be of relevance regarding its appropriate use as biosorbents and recycled by-products.

Metalaxyl mobility in acid soils: Evaluation using different methods

International Journal of Environmental Science and Technology 

DOI: 10.1007/s13762-014-0612-1

In the present work, different methods were tested to evaluate the adsorption and desorption of metalaxyl in two acid soils with different organic carbon and clay contents. The three methods (batch, stirred flow chamber and column) that were examined produced similar findings when the two soils were compared: (a) the metalaxyl adsorption capacity was higher in the soil with higher organic matter and clay content, and (b) the soil with the lower organic matter and clay contents provided higher adsorption rate constants. In the two soils tested, the metalaxyl adsorbed in the soil was highly reversible. When only one soil was considered, the different methods yielded different results. The metalaxyl adsorption and its rate were higher with the stirred flow chamber than in the column experiments, and in the column experiments, the total metalaxyl adsorption and the rate of adsorption were higher than in the batch experiments. The percentages of metalaxyl desorbed from the soil were similar in the stirred flow chamber and column experiments, but in the batch experiments, the percentages were significantly lower. In the stirred flow chamber experiments, the desorption processes were faster than the adsorption processes, while in the column experiments, the adsorption and desorption processes exhibited similar rates.

Time evolution of the general characteristics and Cu retention capacity in an acid soil amended with a bentonite winery waste

Journal of Environmental Management

DOI: 10.1016/j.jenvman.2014.12.024

The effect of bentonite waste added to a "poor" soil on its general characteristic and copper adsorption capacity was assessed. The soil was amended with different bentonite waste concentrations (0, 10, 20, 40 and 80Mgha-1) in laboratory pots, and different times of incubation of samples were tested (one day and one, four and eight months). The addition of bentonite waste increased the pH, organic matter content and phosphorus and potassium concentrations in the soil, being stable for P and K, whereas the organic matter decreased with time. Additionally, the copper sorption capacity of the soil and the energy of the Cu bonds increased with bentonite waste additions. However, the use of this type of waste in soil presented important drawbacks for waste dosages higher than 20Mgha-1, such as an excessive increase of the soil pH and an increase of copper in the soil solution.

Heavy metals in pastureland soils situated in A Pastoriza (NW Spain) treated with cattle slurry and NPK fertilizers

Spanish Journal of Soil Science, 5, 154-164 (2015)

DOI: 10.3232/SJSS.2015.V5.N2.05

In Galicia (NW Spain), pasturelands cover a broad extension and are mainly used to feed cattle. Farms are managed in an intensive manner, using cattle slurry and inorganic fertilizers to increase pasture production, but also increasing risks of heavy metal pollution. In this work we studied the influence of fertilization practices on total concentrations and in-depth distribution of heavy metals and related elements (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) in two forest soils (SN1, SN2) and five pastureland soils (P1-P5) fertilized with cattle slurry and NPK, in a broadly exploded farmland area (A Pastoriza, Lugo). Soils SN2 and P4 were developed over slate, whereas soils SN1, P1, P2, P3 and P5 evolved on Candana quartzite. Forest soils presented acid pH (4.58-4.68), high Al saturation (75-90%), and low available P concentration (4.78-11.96 mg kg-1), whereas those parameters exhibited better scores in the pastureland soils, due to previous amendment and fertilization practices, thus giving pH 5.17-7.02, Al saturation 0.58-59.24%, and available P 5.24-42.07 mg kg-1. Regarding heavy metals, soil depth did not affect significantly to total concentrations, contrary to that happening with parent material, with higher As, Cu, Fe, and Ni concentrations found in soils over slate (possibly due to the presence of pyritic materials). In most cases, heavy metal total concentrations were lower than that considered as reference background levels for soils developed over each of the parent materials, and were always lower than that considered phyto-toxic. In this study, natural soils usually presented heavy metal total contents similar or even higher than that of the fertilized soils (unless Zn in the P4 pastureland), thus indicating that the spread doses of fertilizers did not influence significantly their concentration levels.

Profiling, distribution and levels of carcinogenic polycyclic aromatic hydrocarbons in traditional smoked plant and animal foods

Food Control, 59 (2016) 581–590

doi:10.1016/j.foodcont.2015.06.036

The purpose of this study was to evaluate the concentration of polycyclic aromatic hydrocarbons (PAH8 plus fluoranthene and pyrene) in “Pan de Cea” bread, “Pimentón de La Vera” paprika, “San Simón da Costa”, “Idiazábal” and “Humus” cheeses, and “Chorizo” garlic pork sausage. Results obtained showed that harmless low molecular weight compounds (Fluoranthene and Pyrene) represented the major contribution to the total PAHs. The most important PAHs according to the levels found were those in the 4 PAHs group (the rest of PAHs to add a total of 8 were contributing at very low levels). PAH4 and PAH8 levels showed percentages ranging from 6.0 to 7.0 % in bread, 16–17 % in paprika, 23–28 % in cheese and 20–24 % in meat sausages, respectively. B(a)P did not exceed the imposed limits in the EU. Bread showed the lower PAH concentration (3.4 μg/kg) followed by cheese (88 μg/kg), smoked sausage (1779 μg/kg) and paprika (9937 μg/kg). “Pimentón de la Vera” paprika is a condiment consumed in small quantities. The PAH profile had in common the decrease in PAH content as their molecular weight increased. These results showed that the contamination detected in “Pan de Cea” bread samples was very low, so that the consumption of this product does not pose a health risk. In cheese samples, the PAH contamination was detected meanly in rind, that accounted around the 100% of the total contamination. In meat sausages samples, the 90% of the total PAHs determined were accumulated in the casing. Considering the edible part, the PAH4 and B(a)P mean contents were below the limit established. Although, the highest PAH levels were detected in “Pimentón de la Vera” paprika, it should be pointed out that this product is a condiment consumed in small quantities and not in an everyday basis, it does not represent a risk for consumers. In cheese and meat sausage, according our estimates, the removal of the external part can be considered a good consumer practices to reduce the ingestion of PAHs.