DIQAM-Artículos

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Acute and repeated dose (4 weeks) oral toxicity studies of two antihypertensive peptides, RYLGY and AYFYPEL, that correspond to fragments (90–94) and (143–149) from αs1-casein
(Elsevier Ltd., 2010-07) Anadón, Arturo; Martínez-Caballero, María Aranzazu; Ares, Irma; Ramos-Alonso, Eva; Martínez-Larrañaga, María Rosa; Contreras-Gámez, María Mar; Ramos-González, Mercedes; Recio, Isidra
The Lowpept® is a powdered casein hydrolysate containing the antihypertensive peptides RYLGY and AYFYPEL, two sequences that correspond to αs1-casein f (90–94) (RYLGY) and αs1-casein f (143–149) (AYFYPEL). To support the safety, Lowpept® has been examined in an acute and in a 4-week repeated dose oral toxicity studies in rats. Powdered casein hydrolysate administered in a single oral gavage dose of 2000 mg/kg resulted in no adverse events or mortality. Also, casein hydrolysate administered as a daily dose of 1000 mg/kg for 4 weeks by gavage resulted in no adverse events or mortality. No evidence or treatment-related toxicity was detected during both studies. Data analysis of body weight gain, food consumption, clinical observations, blood biochemical, haematology, organ weight ratios and histopathological findings did not show significant differences between control and treated groups. It is concluded that the casein hydrolysate containing the peptides RYLGY and AYFYPEL orally administered to rats was safe and that not treatment-related toxicity was detected even at the highest doses investigated in both acute (2000 mg/kg of body weight) and repeated dose (4 weeks) oral (1000 mg/kg of body weight) toxicity studies.
Alkaline activated cements obtained from ferrous and non-ferrous slags. Electric arc furnace slag, ladle furnace slag, copper slag and silico-manganese slag
(Elsevier, 2024-03) Gómez-Casero , Miguel Ángel; Bueno, Salvador; Castro-Galiano, Eulogio; Eliche-Quesada, Dolores
Ferrous slag: electric arc furnace slag (EAFS) and ladle furnace slag (LFS); and non-ferrous slag: copper slag (CS) and silicon-manganese slag (SiMnS) have been used as precursors for alkali activated cements (AACs). The objective of the study was to evaluate the effect of the silica modulus (Ms = SiO2/K2O) (0.5–1.8) of the potassium silicate/potassium hydroxide solution on the microstructure and technological properties of AACs using individual slags. The results obtained indicate that under the activation conditions used, CS and EAFS are more reactive slags, giving rise to AACs with optimum flexural and compressive strengths of 7.5 and 51.5 MPa and 5.7 and 30.5 MPa for a Ms = 1.4, respectively. While the SiMnS and LFS are less reactive resulting in AACs with flexural and compressive strengths of 3.2 and 11.6 MPa at Ms = 1.4 for SiMnS and 1.1 MPa and 4.6 MPa at Ms = 0.9 for LFS. In all AACs, the development of the alkaline activation reaction is confirmed due to the presence of gel, of different nature and quantity depending on the precursor used. The lower mechanical properties of the AACs using SiMnS and LFS as precursor may also be due to the presence of microcracks. Therefore, this study confirms that ferrous and non-ferrous slags can be used as precursors of AACs, with the type of precursor and the modulus of the activating solution influencing mechanical properties. AACs using CS and EAFS can be used in structural applications, while those using SiMnS and LFS can be used in non-structural applications in civil engineering.
Biorefining for olive wastes management and efficient bioenergy production
(Elsevier, 2021) Najafi, Elham; Castro, Eulogio; Karimi, Keikhosro
The potential of olive wastes for development of a multi-product biorefinery was investigated. Different parts of olive wastes, i.e., stone, pomace, leaves, and wood, were subjected to liquid hot water, organosolv, and acid-catalyzed organosolv (ACO) pretreatments prior to bioconversion through three different scenarios. The first scenario, i.e., anaerobic digestion of substrates for biogas production, yielded 219.3 m3 biomethane per hectare of olive trees, equated to 247.4 L gasoline. The highest methane production of 103.3 m3 was attributed to liquid hot water pretreated wood and ACO increased methane yield for leaf and stone samples by 200 and 33%, respectively. The second scenario, i.e., fermentation of wastes for bioethanol production, resulted in 295.9 L bioethanol per hectare of olive trees, equivalent to 196.1 L gasoline. Organosolv pretreated wood with 82.9% production yield and 152.5 L bioethanol constitutes this plan's dominant part. The ACO pretreatment improved fermentation yield for pomace and stone samples by 49% and 53%, respectively. The third scenario, included the utilization of olive wastes in bioethanol production, anaerobic digestion of fermentation residues, and lignin separation, resulted in 295.9 L bioethanol, 137.2 m3 biomethane, and 347.1 kg lignin, equated with 521.6 L gasoline. Furthermore, the remaining oil content in pomace and stone samples was 17% and 20%, respectively, which could be used for biodiesel production. Overall, olive wastes processing through an integrated biorefinery plant with multiple products significantly improved the energy recovery of the whole plant.
Comparative Life Cycle Assessment of Lightweight Aggregates Made from Waste—Applying the Circular Economy
(MPDI, 2022-02-12) Uceda-Rodríguez, Moreno-Maroto, J.M. M.; Cobo-Ceacero, López-García, A.B. C.J.; Cotes-Palomino, Martínez-García, C T.
Abstract The application of Life Cycle Assessment in the construction sector can be a very useful tool to reduce the environmental impact generated by the sector. In order to quantify the improvement in environmental terms with the use of artificial lightweight aggregates (LWA) manufactured with waste, in this work, we conducted a comparative evaluation of the life cycle of LWAs for a total of five different scenarios: LWAs obtained in a traditional way, i.e., using exclusively clay in their manufacture (Spanish blond clay, Portuguese red clay and Portuguese blond clay), and LWAs manufactured with four different wastes, with a partial substitution of 2.5% for each of the clays per waste (almond and hazelnut shells, sludge from the purification of paper money, cork dust and coffee grounds). The functional unit was set as the production of 1 kilo of lightweight aggregates and the CML 2000 methodology and the SimaPro software were used. The results obtained in this research allow us to conclude that the addition of organic wastes showed a slightly higher environmental performance than the conventional system, the ALAs manufactured with almond and hazelnut shells being the most environmentally friendly option, with reductions of more than 30% in some cases, followed by the LWAs manufactured with coffee grounds. On the other hand, the addition of paper sewage sludge and cork dust represents minimal environmental optimization.
Ephedra alata Subsp. Alenda as a novel source of bioactive phytochemicals: Characterization based on the mass spectrometry and profiling of antioxidant and anti-Inflammatory properties.
(MDPI, 2023-01-23) Mufti, Afoua; Contreras, María del Mar; Gómez-Cruz , Irene; Alshamrani, Abdullah; Nahdi, Saber; Mansour, Lamjed; Alwasel, Salah; Halim Harrath, Abdel; Tlili, Nizar
The aim of the present study was to examine, for the first time, the phytochemical content of Ephedra alata pulp extract (EAP) and explore its antioxidant and anti-inflammatory capacities. High-performance liquid chromatography-electrospray ionization-quadrupole-time-of-flight mass spectrometry (HPLC-ESI-QTOF/MS) was used for phytochemical analysis and three in vitro antioxidant assays together with three in vitro anti-inflammatory tests were used for the assessment of biological activity. The HPLC-ESI-QTOF/MS analysis revealed the presence of 42 metabolites, including flavonoids, sphingolipides, fatty acids, ephedrine derivatives, and amino acid derivatives. In vitro findings revealed that EAP has interesting 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide, and ferrous ion chelating capacities (IC50 values were 0.57 mg/mL, 0.55 mg/mL, and 0.51 mg/mL for DPPH, superoxide radical, and ferrous ion, respectively). Furthermore, EAP showed a noticeable anti-inflammatory ability by inhibiting the two cyclooxygenase isoforms, COX-1 and COX-2 (IC50 of 59.1 and 58.8 µg/mL for COX-1 and COX-2, respectively), preventing protein denaturation (IC50 = 0.51 mg/mL), and protecting membrane stabilization (IC50 = 0.53 mg/mL). The results highlighted the use of Ephedra alata pulp as a potential source of natural compounds with therapeutic effects for the management of inflammatory disorders.
Experimental and numerical study of the laser transmission welding between PA6/sepiolite nanocomposites and PLA
(Elsevier, 2020-10-15) Moya-Muriana, José Ángel; Yebra-Rodríguez, África; Navas-Martos, Francisco J.; La Rubia, M.Dolores
PA6/sepiolite nanocomposites have been manufactured at different wt% sepiolite loading and a fixed minimum load of a IR absorber additive (CAA). Nanocomposites were characterised and welded with PLA specimens through transmission laser welding technology (TLWT). Resulting welded specimens were also characterised. Experimental data obtained from the characterisations were introduced and processed in a Computer-Aided Engineering (CAE) software to obtain a suitable fracture model based on cohesive zone model (CZM) and capable of predicting the behaviour of the nanocomposite/PLA welds against shear forces. A correlation analysis was performed to assess the goodness of fit between the experimental and simulation data.
Fracture behaviour of microcrack-free alumina-aluminium titanate ceramics with second phase nanoparticles at alumina grain boundaries
(Elsevier, 2008) Bueno, Salvador; Berger, Marie Hélène; Moreno-Botella, Rodrigo
Alumina + 10 vol.% aluminium titanate composites were obtained by colloidal filtration and reaction sintering of alumina and titania. The materials were dense with aluminium titanate grains of average sizes 2.2–2.4 μm located mainly at alumina triple points. The reaction sintering schedule promoted the formation of additional nanometric grains, identified as aluminium titanate using STEM–EDX analysis between the alumina grains. This special microstructure led to a change of the toughening mechanism from the typical crack bridging reported for microcrack-free composites fabricated from alumina and aluminium titanate powders to microcracking. The identification of microcracking as the main toughening mechanism was done from the analysis of stable fracture tests of SENVB samples in three points bending and fractographic observations. Monophase alumina materials with similar grain sizes were used as reference. Different fracture toughness parameters were derived from the load–displacement curves: the critical stress intensity factor, KIC, the critical energy release rate, GIC, the J-Integral and the work of fracture, γWOF, and the R curves were also built. The comparison between the linear elastic fracture parameters and the non-linear ones revealed significant toughening and flaw tolerance.
Hepatopreventive properties of hydroxytyrosol and mannitol-rich extracts obtained from exhausted olive pomace using green extraction methods
(Royal Society of Chemistry, 2022-12-25) Contreras, María del Mar; Gómez -Cruz, Irene; Feriani, Anouar; Alwasel, Saleh; Harrath, Abdel Halim; Romero-Pulido, Inmaculada; Castro-Galiano, Eulogio; Tlili, Nizar
Exhausted olive pomace (EOP) is produced in olive-pomace oil extractors as a by-product. However, the obtention of bioactive compounds from EOP can reinsert it into the economy as a new bioresource before applying other exploitation ways. The objective of the present study was to investigate the phytochemical differences between aqueous and aqueous acetonic extracts from EOP (AE-EOP and AAE-EOP, respectively) obtained by hydrothermal and ultrasound-assisted extraction, respectively. The in vitro antioxidant activities and the in vivo hepatopreventive potential were evaluated. Using RP-HPLC–ESI–QTOF– MS, the chemical profile revealed that AE-EOP and AAE-EOP showed similar qualitative profiles, with some quantitative differences. Hydroxytyrosol and mannitol were the major compounds of the extracts. The investigation of antioxidant properties in vitro highlighted that AE-EOP was slightly more efficient in scavenging DPPH, ABTS, superoxide, and hydrogen peroxide radicals, when compared to AAE-EOP. Additionally, AE-EOP and AAE-EOP showed dose-dependent suppressive effects on pancreatic lipase activity. In vivo studies showed that AE-EOP and AAE-EOP presented interesting hepatopreventive capacities against CCl4 induced liver injury, as evidenced by (i) the preventive effects against DNA damage, (ii) the normalised hepatic biomarker parameters (ALT, AST, GGT, and LDH) and (iii) the normalised lipid profile (LDL-C, TC, TG, and HDL-C) through diminishing their levels, (iv) which was supported by Oil Red O analysis. Furthermore, AE-EOP and AAE-EOP reduced the oxidative stress in liver tissue by inhibiting lipid peroxidation together with the enhancement of the hepatic antioxidant activities (CAT, SOD and GPx) and GSH content. Additionally, AE-EOP and AAE-EOP exhibited an antifibrotic effect, which was clearly demonstrated by the histopathological examination using Picrosirius red staining. The obtained results support the use of EOP extracts in industries without further purification as antioxidants and against free radical induced damage.
Improved xylitol production from olive stones hydrolysates by biological detoxification
(Elsevier, 2022) Romero-García, Juan MIguel; Fehér, Csaba; Cara, Cristóbal; Ruiz-Ramos, Encarnación; Castro, Eulogio
Olive stones, currently used as a biosource of heat and power, is gaining research interest as a feedstock for a biorefinery based on olive derived wastes. In this work, pure xylitol crystals were obtained and fully characterized as one of the possibilities of taking full advantage of this by-product of olive oil production. The proposed process includes a two-step pretreatment (water and acid extractions), detoxification of the liquid fractions and fermentation of sugars. After the water extraction, a liquid fraction with antioxidant capacity was recovered; the second step was done with dilute sulfuric acid for solubilization of sugars, resulting in a solution containing more than 60 g/l of xylose as the main sugar. This liquor contained also up to 16 g/l acetic acid, which rendered it not fermentable. Also other compounds, potentially inhibitors in downstream operations, were produced during the pretreatment, requiring a detoxification procedure. In this work, a chemical-free, biological treatment with Saccharomyces cerevisiae proved to be the best detoxification method, as glucose, furfural, hydroxymethylfurfural and acetic acid were consumed. The subsequent inoculation of Candida boidinii produced xylitol concentrations above 38 g/l after 90h fermentation time and a yield as high as 63%, equivalent to 12 g xylitol/100 g olive stones.
Multi-stage linear programming model for optimizing cropping plan decisions under the new Common Agricultural Policy
(Elsevier Ltd, 2015-11-01) Galán-Martín, Ángel; Pozo, Carlos; Guillén-Gosálbez, Gonzalo; Antón, Assumpció; Jiménez-Esteller, Laureano
The new European Union’s Common Agricultural Policy will cover the period from 2015 to 2020. Significant novelties in the payment scheme have been introduced which may potentially encourage farmers to implement changes at the farm level by meeting certain environmental requirements in return for support payments. The mandatory requirements, commonly known as ‘greening rules’, consist of crop diversification, maintenance of permanent grassland and establishment of an ecological focus area. This paper presents a decision-support tool based on a multi-stage linear programming model that identifies optimal cropping plan decisions under the new Common Agricultural Policy. The capabilities of our tool are illustrated through its application to the Spanish agricultural regions. Our method identifies the optimal cropping plan (i.e., crops to be grown and their acreage each year during the reform horizon) that maximizes the farmer’s net return in each region. Furthermore, the model can also be used to calculate the minimum subsidy value that would make the implementation of greening rules economically appealing, thereby promoting the widespread adoption of more sustainable agricultural practises.
Production and characterization of cellulose acetate using olive tree pruning biomass as feedstock
(Willey and sons, 2024-01-22) Rodríguez-Liébana, José Antonio; Robles-Solano, Esther; Jurado-Contreras, Sofia; Morillas-Gutiérrez, Francisca; Moya, Alberto J.; Mateo, Soledad; Navas-Martos, Francisco Javier; La Rubia, M.Dolores
Olive tree pruning (OTP) is one of the most abundant sources of biomass waste in the Mediterranean basin. This is especially relevant in southern Spain where olive oil production represents a large part of the economy. Olive tree prunings are mostly either burned or are spread in olive orchards as an organic amendment, or used for heat generation on a domestic scale. However, the lignocellulosic composition of OTP makes it a potential source of biopolymers, thus providing an excellent economic alternative for the olive oil sector. In this work, pretreated OTP fibers were subjected to an optimized alkaline treatment followed by a single-step bleaching reaction with H2O2. Afterwards, the cellulose pulp was transformed chemically to obtain cellulose acetate. Noncellulosic components were removed effectively from OTP, thus obtaining a pulp highly purified in cellulose with 71% crystallinity and 355 °C maximum degradation temperature. Nevertheless, a very large amount of cellulose (ca. 50%) was eliminated throughout the process, especially during acid pretreatment, which was responsible for 38% solubilization. A similar level of acetylation and degree of substitution was obtained by using acetylation times in the range of 1 to 6 h. No large differences were observed in the infrared spectra and X-ray diffractograms of the synthesized acetates. However, their thermal stability varied significantly with reaction time, evolving from a multistep degradation pattern to a single and sharp peak between 300 and 400 °C with increasing time. Thermogravimetric curves revealed that at least 5 h (preferably 6 h) were needed to obtain cellulose acetate from OTP with adequate thermal stability for further processing.
Sustainable vine shoots-to-ethanol valorisation by a sequential acid/organosolv pretreatment
(ELSEVIER, 2024-01-18) Cardoza, D.; Contreras, MdM.; Lara-Serrano, M.; Morales-delaRosa, S.; Campos-Martín, J.M.; Romero, I.; Castro, E.
In this study, a fractionation and valorisation scheme for vine shoots is proposed for biofuel and lignin production. This agricultural waste was fractionated by acid/organosolv sequential pretreatment. In the first step, acid pretreatment was optimised at 150ºC and 1.2% H2SO4 to release hemicellulosic sugars, of which 76% could be recovered. This sugar stream was co-fermented by E. coli with an ethanol yield higher than 98% after detoxification with resins or NH4OH. The solid obtained under optimal acid pretreatment conditions was delignified by organosolv treatment, and a delignification rate of 43% was reached at 180ºC. This substrate with 83% enzymatic digestibility was bio-converted into ethanol by simultaneous saccharification and fermentation, with a yield of 76%. Additionally, lignin was recovered from the organosolv liquor, aiming for the full valorisation of the biomass, which showed a syringyl/guaiacyl ratio of 0.92 by nuclear magnetic resonance, complying with the data provided for Fourier transform infrared spectroscopy and confirming the aromaticity of this fraction for further valorisation.
Synthesis and characterization of alkali-activated materials containing biomass fly ash and metakaolin: effect of the soluble salt content of the residue
(Springernature, 2022-05-07) Jurado-Contreras, Sofía; Bonet-Martínez, Eduardo; Sánchez-Soto, Pedro José; Gencel, Osman; Eliche-Quesada, Dolores
The present study investigates the production and characterization of alkali-activated bricks prepared with mixing metakaolin (MK) and biomass fly ash from the combustion of a mix of pine pruning, forest residues and energy crops (BFA). To use this low cost and high availability waste, different specimens were prepared by mixing MK with different proportions of BFA (25, 50 and 75 wt%). Specimens containing only metakaolin and biomass fly ash were produced for the purpose of comparison. Effects of the alkali content of biomass fly ash, after a washing pretreatment (WBFA), as well as the concentration of NaOH solution on the physical, mechanical and microstructural properties of the alkali-activated bricks were studied. It was observed that up to 50 wt% addition of the residue increases compressive strength of alkali-activated bricks. Alkalinity and soluble salts in fly ash have a positive effect, leading materials with the improved mechanical properties. Concentration of NaOH 8 M or higher is required to obtain optimum mechanical properties. The compressive strength increases from 23.0 MPa for the control bricks to 44.0 and 37.2 MPa with the addition of 50 wt% BFA and WBFA, respectively, indicating an increase of more than 60%. Therefore, the use of biomass fly ash provides additional alkali (K) sources that could improve the dissolution of MK resulting in high polycondensation. However, to obtain optimum mechanical properties, the amount of BFA cannot be above 50 wt%.
Synthesis of clay geopolymers using olive pomace fly ash as an alternative activator. Influence of the additional commercial alkaline activator used
(Elsevier, 2021-06) Gómez-Casero, Miguel A.; Moral Moral, Francisco J.; Pérez Villarejo, Luis; Sánchez Soto, Pedro J.; Eliche Quesada, Dolores
In this research, the use of olive pomace fly ash (OPFA) as an alkaline source for the activation of calcined clays (CC) from Bailen (Jaen, Spain) was studied. The optimal composition was obtained for 70 wt % CC and 30 wt % OPFA. The physical, mechanical and thermal properties of control geopolymers that use water as a liquid medium have been studied and compared with geopolymers that use additional activating solutions as sodium or potassium hydroxide solutions (8 M), or a mixture of alkaline hydroxide and alkaline silicate solution (NaOH-Na2SiO3 or KOH-K2SiO3). The results showed that OPFA can be used as an alkaline activator, showing mechanical properties slightly lower than those obtained when additional alkaline hydroxide activating solutions were used. The best compressive strength was obtained for geopolymers that use alkaline silicates as an activating solution. However, the best thermal insulation properties were obtained for control geopolymers. The microstructural characteristics of the geopolymers were evaluated by means of X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM-EDS) that corroborate the formation of geopolymeric gel in all the specimens, being the amount of gel formed greater in samples using commercial potassium activating solutions. These results demonstrate the feasibility of using this type of waste, OPFA, as activating reagents in the manufacture of geopolymers or alkaline activated materials. The manufactured geopolymers can be used as compressed earth blocks for walls and partitions, since the specimens pursue mechanical properties that comply with current regulations, presenting better thermal insulation properties.
Unraveling the expansion mechanism in lightweight aggregates: Demonstrating that bloating barely requires gas
(ELSEVIER, 2020-06) José Manuel Moreno-Maroto, Carlos Javier Cobo-Ceacero; Manuel Uceda-Rodríguez, Teresa Cotes-Palomino; Carmen Martínez García, Jacinto Alonso-Azcárate
Lightweight aggregate bloating process has been studied by a simple experiment using an archetypal clay to know the actual amount of gas involved in expansion. Considering the relationship between gas loss (LOI) and volumetric changes over time, three main stages are identified: 1) a preheating stage of massive gas loss (close to 80% of the total) with hardly any volumetric change; 2) a very brief transition stage, in which sintering (shrinkage) and closed (micro)porosity formation begin, accompanied by a sudden gas loss (close to 100% of the total); 3) the bloating stage itself, in which an appropriate viscosity is reached, allowing the available residual gas (<0.1 wt%) to increase the aggregate volume due to the growth in size of the micropores formed in the transition phase and probably also to the development of new porosity. Therefore, the proportion of gas-generating components estimated to obtain a highly expanded lightweight aggregate would be much lower than previously thought: e.g., only 0.06 to 0.2% of carbonates (calcite or dolomite) or 0.2 to 1% of Fe2O3 would actually be involved in bloating. These results suggest that obtaining an adequate viscosity appears to be much more decisive for bloating than gas release capacity.

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