Examinando por Autor "Romero, I."
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Ítem Biological hydrogen and furfural production from steam-exploded vine shoots(ELSEVIER, 2023-10-03) Castro, E.; Silva Rabelo, C.; Padilla-Rascón, C.; Vidal, A.; López-Linares, J.C.; Vasreche, M.B.; Romero, I.Vine shoots are an agricultural waste rich in carbohydrates that can be considered as a promising energy source alternative. The objective of this work was to propose a process strategy for the valorisation of this residual biomass, including the chemical conversion of solubilised sugars into furfural and the biological conversion of cellulosic glucose into H2. Vine shoots were subjected to steam explosion pretreatment, and its operational conditions were optimised as 190 ◦C and 1.6% H2SO4 impregnated biomass. These pretreatment conditions allowed to recover 68.2% of the hemicellulose sugars and 18.2% of glucose in the prehydrolysate and 45.3% glucose by enzymatic hydrolysis. Thus, the pretreated solid obtained under optimised conditions was subjected to enzymatic hydrolysis and the slurry generated was used as a substrate by Clostridium butyricum for fermentation into biohydrogen (830.7 mL/L and a yield of 3550 mL per 100 g of raw vine shoots) and organic acids (1495.3 mg acetic acid/L and 1726.8 mg butyric acid/L). Based on furfural production, the chemical conversion of xylose in the prehydrolysate was optimised in a microwave reactor at 202 ◦C, using 0.195 M FeCl3 as a catalyst, with a furfural production of 15 g/L and 73% yield.Ítem Grapevine shoot extract rich in trans-resveratrol and trans-ε-viniferin: evaluation of their potential use for cardiac health(MDPI, 2023-12-02) Contreras, MdM.; Feriani, A.; Gómez-Cruz, I.; Romero, I.; Hfaiedh, N.; Halim Harrath, A.; Castro, E.; Tlili, N.A grapevine shoot extract (GSE) was obtained using ultrasound-assisted extraction and characterized. The main phenolic constituents were identified as stilbenoids. Among them, trans-resveratrol and trans-ε-viniferin stood out. The GSE was administered to an isoproterenol-induced myocardial injury animal model. The extract alleviated the associated symptoms of the administration of the drug, i.e., the plasma lipid profile was improved, while the disturbed plasma ion concentration, the cardiac dysfunction markers, the DNA laddering, and the necrosis of myocardial tissue were diminished. This effect could be related to the anti-oxidative potential of GSE associated with its antioxidant properties, the increased levels of endogenous antioxidants (glutathione and enzymatic antioxidants), and the diminished lipid peroxidative markers in the heart. The results also revealed angiotensin-converting enzyme (ACE)-inhibitory activity, which indicated the potential of GSE to deal with cardiovascular disease events. This work suggests that not only trans-resveratrol has a protective role in heart function but also GSE containing this biomolecule and derivatives. Therefore, GSE has the potential to be utilized in the creation of innovative functional ingredients.Ítem 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.Ítem Vine shoots pre-treatment strategies for improved hydrogen production and metabolites redistribution in Clostridium butyricum(ELSEVIER, 2023-08-25) Silva Rabelo, C.; Vidal, A.; Casanova-González, R.; Romero-García, J.M.; Varesche, M.B.; Romero, I.; Castro, E.This work deals with the use of vine shoots, a renewable, largely available, lacking of alternatives lignocellulosic material as a feedstock for hydrogen production. Physical pre-treatments by steam explosion (SE), chemical by organosolv (OS) and biological by laccase (LAC) were carried out in vine shoots to disrupt the cell fiber and increase the biomass hydrolysis and fermentation into hydrogen (H2). After SE, there was a slight decrease in cellulose and hemicellulose contents in biomass fibers, while a decrease in lignin content occurred after OS pretreatment. There were no quantifiable changes after laccase pre-treatment, however the enzyme-substrate oxidative reactions were favorable for hydrolysis and fermentation since an increase in soluble sugars and H2 production was observed with LAC vine shoots as substrate. 300.1 mL H2/L were obtained from raw material vine shoots, while 649.4, 399.8 and 749.7 mL H2/L were obtained from biomass pre-treated by SE, OS and LAC, respectively. Furthermore, the hydrolysis of pre-treated biomass by addition of cellulase was evaluated to improve H2 production. Higher amounts of H2 were obtained from hydrolyzed biomass in relation to nonhydrolyzed ones (154.2%, 602.0% and 167.1% more with SE, OS and LAC hydrolyzed, respectively). In all cases, the mixed acid pathway was carried out by Clostridium butyricum, since acetic and butyric acids were produced.