Valorisation of blood protein from livestock to produce haem iron-fortified hydrolysates with antioxidant activity

This work was supported by the project PY20_00021 from the Andalusian Regional Government, Spain. The authors would like to thank APC Europe (Barcelona, Spain) for kindly providing the porcine blood meal powder employed for the experiments.Blood is the main by-product from slaughterhouses bearing high levels of suspended solids (18% w/w) and BOD5 (250 000–375 000 mg O2/L), which makes difficult its handling and disposal. This study proposes the valorisation of blood protein to produce enzymatic hydrolysates rich in haemic iron and antioxidant peptides. Haemic iron presents higher bioavailability compared to its inorganic form, but its incorporation into foodstuffs is restrained by its high tendency to oxidation. Six commercial proteases of animal, plant and bacterial origin were employed to produce the enzymatic hydrolysates. Subtilisin and trypsin treatments were able to recover 70% of haem iron as soluble peptides, in contrast with plant enzymes where the proteolysis was reduced. Moreover, some enzymatic treatments led to hydrolysates with high levels of some in vitro antioxidant activities such as radical scavenging (Protamex, IC50 3.52 mg/mL) or metal chelating activity (trypsin, IC50 0.27 mg/mL). We conclude the enzymatic valorisation of blood protein increases haemic iron bioavailability and produces antioxidant peptides. Both properties are of interest for their use as iron fortification supplements.Andalusian Regional Government, Spain PY20_0002

Preliminary hydrogeological characterization of an evaporite karst area (province of Cordoba, South Spain)

The northern sector of the Subbetic Domain in the Betic Cordillera is formed by an olistostrome unit known as the Chaotic Subbetic Complex (CSC). This megabreccia is basically made of Triassic (Keuper) clays and evaporites (gypsum, anhidrite and halite) as well as blocks of other lithologies (limestones, dolostones, sandstones, etc). Despite that low permeability has been traditionally assumed for these materials, water flow and storage through them is likely derived of their aquitard behavior, but also because of the highly permeable conduits generated by dissolution/karstification processes within the evaporite rocks. The geological complexity of the CSC materials determines their hydrogeological heterogeneity, with groundwater flow systems of different length and various scales from recharge areas to discharge zones. Three springs draining the CSC outcrops have been identified around an evaporitic karst plateau located between the Anzur River (to the North) and the Genil River (to the South), in the province of Cordoba (Spain). Data logger devices have been installed in two of them, located at the Anzur River (left margin), providing an hourly record of discharge, electrical conductivity and water temperature. Water samples have been collected fortnightly for subsequent chemical analysis. After two years of record, the results obtained show that the response of the springs to rainfall events is completely different between them. One has a clearly karstic behavior, with a rapid response to recharge whereas the other one is more inertial, and variations in its waters occur in a yearly scale. This is an evidence of the aforementioned hydrogeological heterogeneity of the CSC.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

BI-OBJECTIVE OPTIMISATION OF THE ENZYMATIC HYDROLYSIS OF PORCINE BLOOD PROTEIN

Protein from porcine blood meal was hydrolysed with Alcalase to obtain a final revalorised product suitable, for example, to take part in the composition of an organic fertiliser. Three experimental factors of the reaction (pH, temperature and enzyme-substrate ratio) were optimised by means of a statistically designed experiment and response surface methodology. The goal of the optimisation problem was to maximise both the degree of hydrolysis and solubilisation of the substrate, obtaining a maximum degree of hydrolysis (28.89%) with pH 6.24, 54.2 °C and enzyme-substrate ratio of 10%. Regarding the content of suspended solids, its minimum value (30.29% related to the initial weight of blood meal) was attained at pH 7.5, 59.8 °C and enzyme-substrate ratio of 10%. The controversial effects of pH and temperature on the substrate solubilisation and the final degree of hydrolysis, suggested employing a multiobjective optimisation technique. A Pareto Front was generated in order to find a set of intermediate solutions which satisfied both objectives in an adequate degree.Ministerio de Ciencia e Innovación ( CTQ2008-02978

Nutrient Removal and Membrane Performance of an Algae Membrane Photobioreactor in Urban Wastewater Regeneration

The increase in industry and population, together with the need for wastewater reuse, makes it necessary to implement new technologies in the circular economy framework. The aim of this research was to evaluate the quality of the effluent of an algae membrane photobioreactor for the treatment of the effluent of an urban wastewater treatment plant, to characterise the ultrafiltration membranes, to study the effectiveness of a proposed cleaning protocol, and to analyse the performance of the photobioreactor. The photobioreactor operated under two days of hydraulic retention times feed with the effluent from the Los Vados wastewater treatment plant (WWTP) (Granada, Spain). The microalgae community in the photobioreactor grew according to the pseudo-second-order model. The effluent obtained could be reused for different uses of diverse quality with the removal of total nitrogen and phosphorus of 56.3% and 64.27%, respectively. The fouling of the polyvinylidene difluoride ultrafiltration membrane after 80 days of operation was slight, increasing the total membrane resistance by approximately 22%. Moreover, the higher temperature of the medium was, the lower intrinsic resistance of the membrane. A total of 100% recovery of the membrane was obtained in the two-phase cleaning protocol, with 42% and 58%, respectively.Junta de Andalucia European Commission P18-TP-473

Evaluation of Plant Protein Hydrolysates as Natural Antioxidants in Fish Oil-In-Water Emulsions

In this work, we evaluated the physical and oxidative stabilities of 5% w/w fish oil-in-water emulsions stabilized with 1%wt Tween20 and containing 2 mg/mL of protein hydrolysates from olive seed (OSM-H), sunflower (SFSM-H), rapeseed (RSM-H) and lupin (LUM-H) meals. To this end, the plant-based substrates were hydrolyzed at a 20% degree of hydrolysis (DH) employing a mixture 1:1 of subtilisin: trypsin. The hydrolysates were characterized in terms of molecular weight profile and in vitro antioxidant activities (i.e., DPPH scavenging and ferrous ion chelation). After incorporation of the plant protein hydrolysates as water-soluble antioxidants in the emulsions, a 14-day storage study was conducted to evaluate both the physical (i.e., zeta-potential, droplet size and emulsion stability index) and oxidative (e.g., peroxide and anisidine value) stabilities. The highest in vitro DPPH scavenging and iron (II)-chelating activities were exhibited by SFSM-H (IC50 = 0.05 +/- 0.01 mg/mL) and RSM-H (IC50 = 0.41 +/- 0.06 mg/mL). All the emulsions were physically stable within the storage period, with zeta-potential values below -35 mV and an average mean diameter D[4,3] of 0.411 +/- 0.010 mu m. Although LUM-H did not prevent lipid oxidation in emulsions, OSM-H and SFSM-H exhibited a remarkable ability to retard the formation of primary and secondary lipid oxidation products during storage when compared with the control emulsion without antioxidants. Overall, our findings show that plant-based enzymatic hydrolysates are an interesting alternative to be employed as natural antioxidants to retard lipid oxidation in food emulsions.Regional Ministry of Economic Transformation, Industry, Knowledge, and Universities of Andalusia (Spain) PY20_00021Colombian Ministry of Science, Technology and Innovatio

Estudio preliminar de la hidrodiversidad de humedales andaluces de origen kárstico-evaporítico

Los resultados preliminares obtenidos muestran una gran variedad de facies hidroquímicas (Fig. 3 y 4) y un amplio rango de mineralización de las aguas (Fig. 3 y Tab. 1). Los valores isotópicos de δ18O y δD de las muestras (Fig. 5) indican un enriquecimiento isotópico y presentan un claro desvío con respecto a las líneas meteóricas local y global. Ello demuestra la influencia de la evaporación sobre el agua de los humedales estudiados, más patente en el caso de lagunas estacionales con periodo de inundación prolongado que en aquellas con un hidroperiodo más efímero. Las aguas de las lagunas permanentes, pese a estar expuestas de forma continua a la evaporación, se sitúan en la figura 5 en una posición intermedia, lo que podría deberse a la mezcla de aguas evaporadas con otras de aporte subterráneo. Los humedales de génesis kárstico-evaporítica, pese a tener un origen similar, presentan una gran diversidad geomorfológica, hidrológica e hidrogeológica como consecuencia de condiciones topográficas y geológicas particulares así como de su ubicación dentro de sistemas de flujo subterráneo locales, intermedios o regionales. Dichas particularidades han de ser tomadas en consideración a la hora de gestionar estas áreas naturales y plantear medidas de conservación y restauración, por lo que es necesario profundizar en el conocimiento hidrogeológico de los CCS y de la relación de las aguas subterráneas con los humedales formados en este contexto.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Grupo Español de la Asociación Internacional de Hidrogeólogo

Direcciones de drenaje en la vertiente sur de Sierra Almijara (Málaga). Influencia de la fracturación

6 páginas, 2 figuras, 1 tabla.[EN] The orientation of more than 2000 stream segments (orders 1 to 3, Strahler method) belonging to the drainage system of the Sierra Almijara southern slope (Málaga, Spain) has been measured. The main outcrops in the study area are carbonates of the Alpujárride Complex (Betic Cordillera). The obtained distribution has been compared with the results of more than 3000 measures of fracture directions, part of which have been recorded incide an important cavity (the Nerja Cave). The analysed fractures can be grouped in three families: (a) NW-SE to NNW-SSE, (b) E-W to WNW-ESE and (c) NE-SW to NNESSW. The (a) and (c) families show more frequent karstification evidences. The (b) family is more abundant in the stream distribution. The lack of a good agreement bet*ween these distributions (fracture and stream orientations) can be explained by the combined effect of the recent uprising of the mountainous massif together with the existence of less-resistant layers in the carbonate formation which have been taken preferently for the development of the small length stream drainage pattern.[ES] A partir de la red de drenaje de la vertiente sur de Sierra Almijara (Málaga), acupada mayoritariamente por materiales carbonatados del Complejo Alpujárride (Cordilleras Béticas), se ha obtenido la distribución de la orientación de los cauces de menor longitud (algo más de 2000 segmentos; órdenes 1 a 3, criterio de Strahler). Esta distribución se ha comparado con la de la orientación de más de 3000 diaclasas, parte de las cuales se han medido en una importante cavidad accesible (Cueva de Nerja). Las fracturas medidas se agrupan en tres familias: (a) NO-SE a NNO-SSE. (b) E-O a ONO-ESE y (c) NE-SO a NNESSO. Las familias (a) y (c) son las que aparecen karstificadas con más frecuencia. En la distribución de la orientación de los cauces predomina la familia (b). No se aprecia una buena correspondencia entre la distribución de la orientación de fracturas y cauces. Esto se explica por efecto del importante encajamiento fluvial que existe en el área, debido a la reciente elevación del macizo y a la existencia de niveles menos resistentes en la formación carbonatada que han sido aprovechados preferentemente en el desarrollo de los cursos de menor longitud.Investigación subvencionada por el Patronato de la Cueva de Nerja. La participación de uno de los autores (C.S. de G.) se enmarca, además, en el Proyecto PB91-0079 de la CICYT.Peer reviewe

Production of goat milk protein hydrolysate enriched in ACE-inhibitory peptides by ultrafiltration

A global process for the production of goat milk hydrolysates enriched in angiotensin converting enzyme (ACE) inhibitory peptides was proposed. Firstly, the protein fractions (caseins and whey proteins) were separated by ultrafiltration through a 0·14 μm ceramic membrane. The casein fraction obtained in the retentate stream of the above filtration step was subsequently hydrolysed with a combination of subtilisin and trypsin. After 3 h of reaction, the hydrolysate produced presented an IC50 of 218·50 μg/ml, which represent a relatively high ACE inhibitory activity. Finally, this hydrolysate was filtered through a 50 kDa ceramic membrane until reaching a volume reduction factor of 3. The permeate produced presented an improvement of more than 30% in the ACE inhibitory activity. In contrast, the retentate was concentrated in larger and inactive peptides which led to a decrease of more than 80% in its inhibitory activity. The process suggested in this work was suitable to obtain a potent ACE inhibitory activity product able to be incorporated into food formulas intended to control or lower blood pressure. Moreover, the liquid product could be easily stabilised by spray dried if it would be necessary.Consejería de Economía, Innovación, Ciencia y Empleo de Junta de Andalucía (P07-TEP-02579

Cursos de nivel cero para las titulaciones de primer ciclo de Ciencias

6 páginas, 5 figuras, 2 tablas.Dentro de la política de apoyo a las iniciativas que en materia docente debe realizar la Universidad, en el ámbito de la innovación y para conseguir los niveles de calidad y excelencia necesarios para una adecuada formación y capacitación de los estudiantes, resulta muy importante ofrecer herramientas que ayuden al estudiante a completar o adquirir conceptos previos para así poder después conectarlos con la nueva información que están recibiendo o van a recibir durante su primer año de titulación. En este sentido, la elaboración de unos cursos de nivel cero de las materias básicas: Matemáticas, Física, Química, Biología y Geología que, mediante el uso de la plataforma docente SWAD (Sistema Web de Apoyo a la Docencia: https://swad.ugr.es), permitirá que, antes del comienzo del curso académico, aquellos alumnos que lo consideren necesario o imprescindible, puedan trabajar con aquellas asignaturas básicas en las que sus conocimientos sean más deficientes o consideren que necesitan revisar. Esto ayudará a reducir el número de abandonos en el primer curso de la titulación ya que su realización permite que el alumno adquiera una base suficiente para abordar los contenidos de las asignaturas, facilitándoles la asimilación y comprensión de los contenidos de las mismas.Peer reviewe