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Glycogen store disease; Muscle fatigue; Substrate oxidation Enfermedad de almacenamiento de glucógeno; Fatiga muscular; Oxidación del sustrato Malaltia d'emmagatzematge de glucogen; Fatiga muscular; Oxidació del substrat Carbohydrate availability affects fat metabolism during exercise; however, the effects of complete muscle glycogen unavailability on maximal fat oxidation (MFO) rate remain unknown. Our purpose was to examine the MFO rate in patients with McArdle disease, comprising an inherited condition caused by complete blockade of muscle glycogen metabolism, compared to healthy controls. Nine patients (three women, aged 36 ± 12 years) and 12 healthy controls (four women, aged 40 ± 13 years) were studied. Several molecular markers of lipid transport/metabolism were also determined in skeletal muscle (gastrocnemius) and white adipose tissue of McArdle (Pygm p.50R∗/p.50R∗) and wild-type male mice. Peak oxygen uptake (V˙O2peak), MFO rate, the exercise intensity eliciting MFO rate (FATmax) and the MFO rate-associated workload were determined by indirect calorimetry during an incremental cycle-ergometer test. Despite having a much lower V˙O2peak (24.7 ± 4 vs. 42.5 ± 11.4 mL kg−1 min−1, respectively; P < 0.0001), patients showed considerably higher values for the MFO rate (0.53 ± 0.12 vs. 0.33 ± 0.10 g min−1, P = 0.001), and for the FATmax (94.4 ± 7.2 vs. 41.3 ± 9.1 % of V˙O2peak, P < 0.0001) and MFO rate-associated workload (1.33 ± 0.35 vs. 0.81 ± 0.54 W kg−1, P = 0.020) than controls. No between-group differences were found overall in molecular markers of lipid transport/metabolism in mice. In summary, patients with McArdle disease show an exceptionally high MFO rate, which they attained at near-maximal exercise capacity. Pending more mechanistic explanations, these findings support the influence of glycogen availability on MFO rate and suggest that these patients develop a unique fat oxidation capacity, possibly as an adaptation to compensate for the inherited blockade in glycogen metabolism, and point to MFO rate as a potential limiting factor of exercise tolerance in this disease. Research by the IA and CR-L group is funded by the Biomedical Research Networking Centre on Frailty and Healthy Aging (CIBERFES, CB16/10/00314 and CB16/10/00477). IR-G is supported by a postdoctoral contract from Universidad de Castilla–La Mancha (2021/5937). PLV is supported by a Sara Borrell contract from Instituto de Salud Carlos III (CD21/00138). Research by AL and TP is funded by the Spanish Ministry of Economy and Competitiveness and Fondos FEDER (PI18/00139 and PI19/01313, respectively).

Although antioxidants can act locally to react with an oxidant, oral administration of “antioxidants” is quite useless in treating oxidative stress in tissues. Furthermore, it does not make sense to consider a vitamin as an antioxidant, but vitamin B3 leads to the in vivo formation of compounds that are essential for reducing this stress. A rigorous treatment of the subject indicates that to deal with oxidative stress, the most direct approach is to enhance the innate antioxidant mechanisms. The question is whether this is possible through daily activities. Diets can contain the necessary components for these mechanisms or may induce the expression of the genes involved in them. Another possibility is that pro-oxidant molecules in food increase the sensitivity and power of the detoxification pathways. This option is based on well-known DNA repair mechanisms after exposure to radiation (even from the Sun), or strong evidence of induction of antioxidant capacity after exposure to powerful pro-oxidants such as H2O2. More experimental work is required to test whether some molecules in food can increase the expression of antioxidant enzymes and/or improve antioxidant mechanisms. Identifying effective molecules to achieve such antioxidant power is critical to the food and nutraceutical industries. The potential of diet-based interventions to combat oxidative stress must be viewed from a new perspective.

Perfluorocycloparaphenylenes (PFCPPs) are cycloparaphenylenes (CPPs) in which all hydrogen atoms have been replaced by fluorine atoms. Like CPPs, PFCPPs are highly strained, hoop-shaped π-conjugated molecules. In this article, we report a computational modeling of photoinduced electron transfer processes in the inclusion complex of PF[10]CPP with C60 fullerene. Its unique feature is the favorable electron transfer from C60 to the host molecule. The photooxidation of C60 is predicted to occur on a sub-nanosecond timescale. The PF[10]CPP⊃C60 dyad is the first nanoring-fullerene complex in which C60 acts as an electron donor in the photoinduced charge separation We are grateful for financial support from the Spanish MINECO (Network RED2018-102815-T, project PID2020-113711GB-I00, and Juan de la Cierva contract IJC2019-039846-I to A. J. S.), the Catalan DIUE (2017SGR39), and the University of Girona (POSTDOC-UdG 2021/31 to O. A. S.) Open Access funding provided thanks to the CRUE-CSIC agreement with Wiley

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2022, Tutor: Xavier Companyó Montaner, This project aims to explore how aminocatalysis and electrocatalysis can be synergistically implemented to develop novel sustainable and efficient functionalization of carbonylic compounds. To do so, the one-electron oxidation or reduction of classic amino-catalytic intermediates –enamines and iminium ions– have been investigated into indirect electrocatalytic processes with the use of redox mediators. In the actual catalytic conditions, enamines and iminium ions are formed in situ by the reaction between a carbonyl compound and the primary or secondary amine catalyst. In this work, to assess the feasibility and efficiency of the electron-transfer processes, the enamines and iminium ions of both aldehydes and ketones have been synthesized and isolated. On the other hand, three different redox mediators have also been synthesized to evaluate them, together with some commercially available compounds, as electrocatalysts. The assessment of the electrocatalytic interactions between the redox mediators and the aminocatalytic intermediates has been performed using cyclic voltammetry experiments

S=2 oxoiron(IV) species act as reactive intermediates in the catalytic cycle of nonheme iron oxygenases. The few available synthetic S=2 FeIV=O complexes known to date are often limited to trigonal bipyramidal and very rarely to octahedral geometries. Herein we describe the generation and characterization of an S=2 pseudotetrahedral FeIV=O complex 2 supported by the sterically demanding 1,4,7‐tri‐tert‐butyl‐1,4,7‐triazacyclononane ligand. Complex 2 is a very potent oxidant in hydrogen atom abstraction (HAA) reactions with large non‐classical deuterium kinetic isotope effects, suggesting hydrogen tunneling contributions. For sterically encumbered substrates, direct HAA is impeded and an alternative oxidative asynchronous proton‐coupled electron transfer mechanism prevails, which is unique within the nonheme oxoiron community. The high reactivity and the similar spectroscopic parameters make 2 one of the best electronic and functional models for a biological oxoiron(IV) intermediate of taurine dioxygenase (TauD‐J)., A highly reactive S=2 pseudotetrahedral oxoiron(IV) complex 2 supported by a sterically demanding 1,4,7‐tri‐tert‐butyl‐1,4,7‐triazacyclononane ligand has been synthesized and spectroscopically characterized as one of the best electronic and functional models for a biological oxoiron(IV) intermediate of taurine dioxygenase (TauD‐J).

Investigation of photoinduced electron transfer (PET) in a series of experimentally reported complexes of fullerene with phosphangulene oxides shows that the replacement of O atoms in the bridge of phosphangulene with S atoms promotes efficient and ultrafast ET from fullerene to phosphangulene oxide in PGOOSS⊃C60 and PGOSSS⊃C60 complexes. The results obtained can be useful in development of photovoltaic devices based on phosphangulenes We are grateful for financial support from the Spanish MINECO (Network RED2018-102815-T, project CTQ2017‐85341‐P, and Juan de la Cierva contract IJC2019-039846-I to A.J.S. and FJCI‐2017‐32757 to O.A.S.) and the Catalan DIUE (2017SGR39)

The urgency to move from critical raw materials to highly available and renewable feedstock is currently driving the scientific and technical developments. Within this context, the abundance of natural resources like chitosan paves the way to synthesize biomass-derived nitrogen-doped carbons. This work describes the synthesis of chitosan-derived N-doped mesoporous carbon in the absence (MC-C) and presence (N-MC-C) of 1,10-phenanthroline, which acted as both a porogen agent and a second nitrogen source. The as-prepared MC-C and N-MC-C were thoroughly characterized and further employed as catalytic materials in gas-diffusion electrodes (GDEs), aiming to develop a sustainable alternative to conventional GDEs for H2O2 electrogeneration and photoelectro-Fenton (PEF) treatment of a drug pollutant. N-MC-C presented a higher content of key surface N-functionalities like the pyrrole group, as well as an increased graphitization degree and surface area (63 vs 6 m2/g), comparable to commercial carbon black. These properties entailed a superior activity of N-MC-C for the oxygen reduction reaction, as confirmed from its voltammetric behavior at a rotating ring-disk electrode. The GDE prepared with the N-MC-C catalyst showed greater H2O2 accumulation, attaining values close to those obtained with a commercial GDE. N-MC-C- and MC-C-derived GDEs were employed to treat drug solutions at pH 3.0 by the PEF process, which outperformed electro-oxidation. The fastest drug removal was achieved using N-MC-C, requiring only 16 min at 30 mA/cm2 instead of 20 min required with MC-C. The replacement of the dimensionally stable anode by a boron-doped diamond accelerated the degradation process, reaching an almost complete mineralization in 360 min. The main degradation products were identified, revealing the formation of six different aromatic intermediates, alongside five aliphatic compounds that comprised three nitrogenated structures. The initial N was preferentially converted into ammonium.

This manuscript proves the reproducibility and robustness of cerium oxide nanoparticles, nanoceria, employed as a chemical reagent with oxidizing capacity (as an electron sink) at acidic pH. Unlike nanoceria multi-enzyme-mimetic capabilities at neutral or high pH, nanoceria can behave as a stoichiometric reagent at low pH where insoluble Ce4+ ions transform into soluble Ce3+ in the nanocrystal that finally dissolves. This behaviour can be interpreted as enzyme-like when nanoceria is in excess with respect to the substrate. Under these conditions, the Ce3+/Ce4+ ratio in the NPs can easily be estimated by titration with ferrocyanide. This procedure could become a rapid assessment tool for evaluating nanoceria capacity in liquid environments., N. Sabaté would like to acknowledge the financial support received from ERC Consolidator Grant (SUPERCELL – GA.648518). N. G. B and V. P. acknowledge financial support from the Spanish Ministerio de Ciencia, Innovación y Universidades (MCIU) (RTI2018-099965-B-I00, AEI/FEDER,UE) proyectos de I + D + i de programación conjunta internacional MCIN/AEI (CONCORD, PCI2019-103436) cofunded by the European Union and Generalitat de Catalunya (2017-SGR-1431). ICN2 is supported by the Severo Ochoa program from Spanish MINECO (SEV-2017-0706) and is funded by the CERCA Programme/Generalitat de Catalunya. Dmitry Galyamin thanks the doctoral program “Electroquímica. Ciència i Tecnologia” of the Universitat Autònoma de Barcelona (UAB).

The health benefits of fruit juices have been associated with their high content of antioxidant compounds. Commercial juice has been traditionally heat-processed to destroy microorganisms and enzymes. However, high temperatures induce undesirable changes in the nutritional value of the juice. High-intensity pulsed electric fields (HIPEF) are being studied as an alternative to heat treatments. In addition, in vitro and in vivo methods have been recommended to determine the antioxidant potential of juices in a complementary manner. Thus, the antioxidant activity of untreated, high-intensity pulsed electric fields (HIPEF) or heat-treated fruit juices (tomato, apple, pineapple and orange) was studied using in vitro (TEAC, DPPH, FRAP and Folin-Ciocalteu) and in vivo assays (Saccharomyces cerevisiae). Vitamin C and total phenolic compounds in these juices were determined. The highest antioxidant activities (12.01 mmol of Trolox/L) were obtained through the Folin-Ciocalteu assay in orange juices. The lowest values (0.119 mmol of Trolox/L) were found in apple juice analysed by the FRAP assay. Vitamin C content varied from 10 mg/L (orange juice) to 344 mg/L (orange juice). The highest concentration of total phenolic compounds was determined in orange juice (1238 mg/L), whereas the lowest value was found in tomato juices (149 mg/L). The effect of HIPEF and thermal processing on the antioxidant potential of juices depended on the fruits used to prepare the juices and the antioxidant activity assay conducted. Vitamin C concentration was directly related to the antioxidant activity analysed by Folin-Ciocalteu and FRAP methods and the S. cerevisiae growth rate. S. cerevisiae yeast can be used as a feasible in vivo assay to further determine the antioxidant activity of fruit juices. This study has been carried out with financial support from Universitat de Lleida through a joint Agrotecnio/IRBLleida grant. This work was also supported by the Ministerio de Economia y Competividad (Spain) through the Project BFU2010-17656 and by the Generalitat de Catalunya (2014SGR/1000). Judit Puigpinos thanks University of Lleida for the predoctoral grant.

In the framework of reducing GHG emissions and accelerating the decarbonization of the road transport sector, vehicle efficiency is a key factor for competitiveness. In this sense, the refining industry can make its contribution by reformulating high-octane petrol fuel. The impact of this type of gasoline from CO2 emission balance, technical feasibility, and economics standpoints has recently been assessed by the petroleum industry with promising results, and new potential boosters that could improve the octane number of standard gasoline are more needed than ever. The present work summarizes a comprehensive review aimed at collecting available data regarding chemical molecules that can be used in advanced gasoline formulations for modern spark-ignited car engines focusing on ash-free technologies. Potential boosters are divided into two categories: high-octane gasoline components and octane enhancer additives, with 2 vol % the considered frontier concentration between them. Targeted chemical compounds examined in the screening for high-octane components include isoparaffins, olefins, aromatics, alcohols, ethers, esters, ketones, furans, and carbonates. Chemical families assessed as additives were anilines, hydrazines, amines, pyridines, quinolines, indoles, N-nitrosamines, iodine compounds, selenium compounds, phenols, formates, oxalates, and, in lesser extension, other families. The scope of the analysis includes not only anti-knock effectiveness but also associated side effects for the engine, possible effects on both human health and the environment, current applications, and compatibility with existing infrastructure, among others. Promising opportunities in the medium- and long-terms for every family of chemical compounds that can potentially improve the anti-knock character of modern gasolines well beyond current specifications worldwide are presented. Furthermore, a few chemical families are identified as the most promising ones to be used in future gasoline formulations, either as high-octane components (such as ethers, ketones, and esters) or as octane booster additives (such as anilines, N-nitrosamines, and phenols).

[eng] X-linked adrenoleukodystrophy (X-ALD) is a rare neurometabolic disease characterized by the loss of function of the peroxisomal transporter ABCD1, which leads to an accumulation of very long-chain fatty acids (VLCFA), inducing the production of mitochondrial reactive oxygen species. Clinical phenotypes in humans range from adrenal insufficiency to fatal inflammatory cerebral demyelination. Abcd1-null mice (Abcd1- mice) develop late-onset axonal degeneration in the spinal cord and locomotor disability resembling the most common phenotype in humans, adrenomyeloneuropathy (AMN). Oxidative stress and mitochondrial dysfunction are key common features in X- ALD patients as well as in Abcd1- mouse. In this thesis, we sought to explore novel therapeutic targets that would contribute to better understand the pathophysiology of the disease, based on the existing knowledge on these common hallmarks of X-ALD. First, we identified a lipidic imbalance in the X-ALD mouse models (Abcd1- and Abcd1-/Abcd2-/- mice), characterized by the presence of lipid droplet (LD) accumulation, due to overactivation of the mTOR/SREBP-1c axis and its target genes (Chapter I). Next, we studied the effect of pharmacological doses of biotin in redox homeostasis and lipid metabolism in the X- ALD mouse models and fibroblasts derived from healthy subjects and X-ALD patients. In a second study, we investigated the role of E2F1, a transcription factor essential for cell cycle and metabolic homeostasis, in X-ALD pathophysiology. To address this objective, we studied E2F1 expression in the X-ALD mouse models. We found out an increase of E2F1, both at mRNA and protein level, in the spinal cord from Abcd1- and Abcd1-/Abcd2-/- mice. Finally, we explored the therapeutic potential of targeting E2F1 in X-ALD mice. We followed a genetic approach by crossing E2F1-deficient mice with the X-ALD mouse models (Chapter II). Both therapeutic strategies, the pharmacological intervention with high-dose biotin and the genetic inactivation of E2F1, led to an amelioration of i) mitochondrial dysfunction, ii) bioenergetic failure, iii) oxidative damage iv) dysregulated inflammatory profile, and most importantly, v) halted axonal degeneration and behavioural abnormalities in X-ALD mice (Chapters I and II). Collectively, these findings reveal an impairment of the mTOR/SREBP-1c axis that controls lipid homeostasis in X-ALD, as well as point to E2F1 as a candidate for the impaired mitochondrial activity and antioxidant response in X-ALD. Finally, the results of this doctoral thesis indicate that therapies based on correcting lipid accumulation and redox imbalance may be valuable strategies to treat X-ALD and other neurodegenerative disorders which share general dysregulation of lipid metabolism, impaired redox homeostasis, mitochondrial dysfunction, and neuroinflammation among their hallmarks., [spa] La adrenoleucodistrofia ligada al cromosoma X (X-ALD) es una enfermedad neurometabólica rara caracterizada por la pérdida de función del transportador peroxisomal ABCD1. Como consecuencia se acumulan ácidos grasos de cadena muy larga, que inducen la producción de especies reactivas de oxígeno en la mitocondria. El fenotipo clínico en humanos es variable, desde la insuficiencia suprarrenal hasta la desmielinización inflamatoria cerebral que suele ser fatal. Los ratones deficientes para el gen Abcd1 (ratones Abcd1-) desarrollan una degeneración axonal de aparición tardía en la médula espinal e incapacidad locomotora, un fenotipo que se asemeja al más común en humanos, la adrenomieloneuropatía (AMN). El estrés oxidativo y la disfunción mitocondrial son características claves en los pacientes con X-ALD, así como en el modelo de ratón. En esta tesis, buscamos explorar nuevas dianas terapéuticas que contribuyan a una mejor comprensión de la fisiopatología de la enfermedad, basándonos en el conocimiento existente sobre estas alteraciones en X-ALD. En primer lugar, identificamos un desequilibrio lipídico en los modelos de ratón X-ALD (Abcd1- y Abcd1-/Abcd2-/-), caracterizado por la acumulación de gotas lipídicas (o lipid droplets, LD), debido a la sobreactivación del eje mTOR/SREBP-1c y sus genes diana (Capítulo I). Después, estudiamos el efecto que tiene la dosis farmacológica de biotina en la homeostasis redox y el metabolismo de los lípidos en los modelos de ratón X-ALD y en fibroblastos derivados de individuos sanos y pacientes con X-ALD. En un segundo estudio, investigamos el papel de E2F1, un corregulador transcripcional esencial para el ciclo celular y la homeostasis metabólica, en la fisiopatología de X-ALD. Para abordar este objetivo, estudiamos la expresión de E2F1 en el modelo de ratón Abcd1-. Descubrimos un aumento de E2F1, a nivel de mRNA y proteína, en la médula espinal de ratones Abcd1- y Abcd1-/Abcd2-/-. Finalmente, exploramos el potencial terapéutico de la administración de dosis farmacológicas de biotina (Capítulo I)/silenciar E2F1 (Capítulo II) en ratones X-ALD. Para el último abordaje, seguimos una aproximación genética, cruzando ratones deficientes en E2F1 con modelos de ratón X-ALD (Capítulo II). En ambos casos, la intervención terapéutica conllevó a una mejora de i) la disfunción mitocondrial, ii) el fallo bioenergético, iii) el daño oxidativo iv) la perturbación del perfil inflamatorio, y, lo que es más importante, detuvo la degeneración axonal y previno las alteraciones del comportamiento en ratones X-ALD (Capítulos I y II). En conjunto, estos hallazgos revelan un deterioro del eje mTOR/SREBP-1c que controla la homeostasis de los lípidos, y apuntan a E2F1 como candidato plausible para la regulación del metabolismo oxidativo, así como de la respuesta antioxidante en X- ALD. Finalmente, los resultados derivados de esta tesis doctoral indican que las terapias basadas en corregir la acumulación de lípidos y el desequilibrio redox pueden ser estrategias valiosas para tratar la X-ALD y otros trastornos neurodegenerativos que compartan la desregulación general del metabolismo de los lípidos, la homeostasis redox alterada, la disfunción mitocondrial y la neuroinflamación entre sus señas de identidad.

This paper presents the model of a solar thermochemical looping CO2/H2O dissociation (CL) unit with commercial ceria as the redox oxygen carrier. The CL unit is integrated in an oxy-fuelled combined cycle power plant as an add-on unit to a 100 MW oxy-fuelled natural gas power plant with carbon capture. The efficiency benefit obtained was investigated. A moving bed counter-current reactor model, developed in ASPEN Plus®, consisting of a series of rigorous continuous stirred reactors (RCSTRs) was used for the simulation of both reduction and oxidation reactors of the CL unit. A kinetic subroutine was developed in FORTRAN and linked with each RCSTR for both reduction and oxidation reactions. It is found that the efficiency of the CL unit varies widely with reduction reactor temperature and operating pressure. Considering three different compositions of the feed gas to the oxidation reactor, the CL unit efficiency is obtained as: 35.41% with CO2 only; 30.84% with H2O only; and 35.26% for a mixture of 86% CO2 and 14% H2O. The lower efficiency for H2O-only operation is due to the heat requirement for water vaporization and the higher compression work required for compressing H2 than CO. The maximum solar to electrical efficiency for the whole add-on unit is found to be 25.44% with a reduction reactor operating at a temperature of 1600 °C and 10−7 bar vacuum pressure. With 0.5 m3 reduction reactor volume and 5 m3 oxidation reactor volume, the maximum net electricity produced by the CL add-on unit is 12.85 MWe. Economic analysis revealed that the major contributors to total plant cost are the hydrogen compressor and solar field and tower, which are the 19% and 39% of the total equipment cost, giving a specific overnight capital cost of 12,136 $/kW with an LCOE of 1321 $/MWh with a capacity factor of 21%. The LCOE drops to 628 $/MWh with a carbon tax of 80 $/tonne of CO2 and increased capacity factor of 26%.

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2021, Tutors: Josep Puigmartí-Luis, Alessandro Sorrenti, James D. Nicholas, Dissipative self-assembly (DSA) is a process that leads to the formation of structures and materials away from the thermodynamic equilibrium state through a controlled exchange of energy and/or matter with the environment1. This form of self-assembly is key in numerous biological processes, and, in living organisms, it enables properties such as self-healing, self-replication, signal processing and motility, among others. Recently, there is a growing interest in developing synthetic supramolecular and colloidal systems that can undergo dissipative self-assembly, for example controlled by the consumption of chemical fuel(s). The overall goal of this TFG project is to develop a colloidal system based on ferrocene-functionalized silica (SiO2) particles whose assembly can be controlled via redox-responsive host-guest interactions between the ferrocene (Fc) moiety and a β-cyclodextrin-dimer that can act as a linker between the particles. The addition of suitable chemical fuels (an oxidant and a reductant) will allow us to regulate the assembly/disassembly of the colloidal system, which depends on the kinetics of the redox process. To achieve this goal, monodisperse non-fluorescent and fluorescent core-shell SiO2 particles were synthesized, and subsequently functionalized with Fc moieties using ‘click’ chemistry. Full physicochemical and size characterization of the particles proved the success of the synthesis and functionalization steps, demonstrating the formation of spherical, monodisperse Fc-functionalized particles with size around 500 nm. Redox kinetic studies with a variety of oxidants and reductants were performed using molecular ferrocene, in order to optimize the experimental conditions to be used for the dissipative self-assembly. These studies showed that FeCl3 and ascorbic acid are the most suitable pair of redox agents for fast redox switching of Fc, whilst H2O2 is more suitable for fine-tuning the redox kinetics. Preliminary self-assembly studies revealed that in the presence of β-cyclodextrin-dimer, Fc-functionalized particles assemble, and could then be disassembled by addition of an oxidant. This result is promising for the development of DSA, and further studies are being carried out to investigate this system in more depth

The asymmetric Mannich reaction is one of the most straightforward methodologies for the enantioselective synthesis of chiral amines. In general, asymmetric Mannich reactions involve the use of imines as electrophiles. However, in recent years, several asymmetric oxidative Mannich reactions have been reported using amines as electrophiles. This review provides an overview of these recent publications, including the different oxidants used and the scope and limitations of the different catalytic systems.

Well-defined fullerene-PEG conjugates, C60-PEG (1) and two C70-PEG (2 and 3 with the addition sites on ab-[6,6] and cc-[6,6]-junctions), were prepared from their corresponding Prato mono-adduct precursors. The resulting highly water-soluble fullerene-PEG conjugates 1-3 were evaluated for their DNA-cleaving activities and reactive oxygen species (ROS) generation under visible light irradiation. Unexpectedly, photoinduced cleavage of DNA by C60-PEG 1 was much higher than C70-PEG 2-3 with higher absorption intensity, especially in the presence of electron donor (NADH) in line with the observed ROS generated via the type I electron transfer pathway. The preference of photoinduced ROS generation from fullerene-PEG conjugates between the type II (energy transfer) and the type I (electron transfer) was found to be difference dependent on the fullerene core (between C60 and C70 )cores and functionalization patterns of C70 (between 2 and 3). This was clearly supported by the electron transfer rate obtained from cyclic voltammetry data and computationally calculated relative rate of each step of the type II and the type I reac-tions, with the finding that type II energy transfer reactions occurred in the inverted Marcus regime, while type I electron transfer reactions proceeded in the normal Marcus regime. This new finding on disparity in the pathways of photoinduced reaction (type I versus type II) provide a new insight in the behaviors of photosensitizers in water and in the design of photodynamic therapy drugs This study was supported in part by the Swiss National Foundation (200021_156097, 205321_17318, Y.Y.), the ETH Research Grant (ETH-2115-2, ETH-25 11-1, Y.Y.), the Spanish MINECO (Network RED2018-102815-T, projects CTQ2017-85341-P and PID2020-113711GB-I00, and Juan de la Cierva contract IJC2019-039846-I to A.J.S.) and the Catalan DIUE (2017SGR39)

MicroRNAs (miRNAs) are small RNAs that do not encode for proteins and play key roles in the regulation of gene expression. miRNAs are involved in a comprehensive range of biological processes such as cell cycle control, apoptosis, and several developmental and physiological processes. Oxidative stress can affect the expression levels of multiple miRNAs and, conversely, miRNAs may regulate the expression of redox sensors, alter critical components of the cellular antioxidants, interact with the proteasome, and affect DNA repair systems. The number of publications identifying redox-sensitive miRNAs has increased significantly over the last few years, and some miRNA targets such as Nrf2, SIRT1 and NF-κB have been identified. The complex interplay between miRNAs and ROS is discussed together with their role in myocardial ischemia-reperfusion injury and the potential use of circulating miRNAs as biomarkers of myocardial infarction. Detailed knowledge of redox-sensitive miRNAs is needed to be able to effectively use individual compounds or sets of miRNA-modulating compounds to improve the health-related outcomes associated with different diseases.

The formidable challenges of controlling site-selectivity, enantioselectivity, and product chemoselectivity make asymmetric C-H oxidation a generally unsolved problem for nonenzymatic systems. Discrimination between the two enantiotopic C-H bonds of an unactivated methylenic group is particularly demanding and so far unprecedented, given the similarity between their environments and the facile overoxidation of the initially formed hydroxylation product. Here we show that a Mn-catalyzed C-H oxidation directed by carboxylic acids can overcome these challenges to yield γ-lactones in high enantiomeric excess (up to 99%) using hydrogen peroxide as oxidant and a Brønsted acid additive under mild conditions and short reaction times. Coordination of the carboxylic acid group to the bulky Mn complex ensures the rigidity needed for high enantioselectivity and dictates the outstanding γ site-selectivity. When the substrate contains nonequivalent γ-methylenes, the site-selectivity for lactonization can be rationally predicted on the basis of simple C-H activation/deactivation effects exerted by proximal substituents. In addition, discrimination of diastereotopic C-H bonds can be modulated by catalyst design, with no erosion of enantiomeric excess. The potential of this reaction is illustrated in the concise synthesis of a tetrahydroxylated bicyclo[3.3.1]nonane enabled by two key, sequential γ-C-H lactonizations, with the latter that fixes the chirality of five stereogenic centers in one step with 96% ee Support by the Spanish Ministry of Science (PGC2018-101737-B-I00 to M.C. and J.d.C. grant to G.O., FJCI-2016-30243), and Gen-eralitat de Catalunya (ICREA Academia Award to M.C. and 2014SGR 862), and from EU (MSCA-ITN-2015 Action NoNoMeCat, 675020) is acknowledged

The Eureka deposit in Castell-estaó in the Catalan Pyrenees is a Cu–U–V deposit, hosted by Triassic red-bed sandstones, and classified here as a low-temperature, sandstone-hosted stratabound metamorphite U deposit. The main mineralisation is stratabound, related to coal-bearing units and produced during the Alpine deformation by migration of hydrothermal fluids. In this stage, the original sedimentary and diagenetic components (quartz and calcite, micas, hematite and locally apatite) were replaced by a complex sequence of roscoelite, fine-grained REE phosphates, sulphides and Ni–Co arsenides and sulpharsenides, Ag–Pb selenides, bismuth phases, sulphosalts and uraninite. The black shales of the Silurian sediments underlying the deposit and the nearby Carboniferous volcanoclastic rocks are interpreted as the source of the redox-sensitive elements concentrated in Eureka. The sulphur source is related to leaching of the evaporitic Keuper facies. The REE transport would be facilitated by SO4-rich solutions. The reduction of these solutions by interaction with organic matter resulted in the widespread precipitation of REE and redox-sensitive elements, including many critical metals (V, Bi, Sb, Co), whereas barite precipitated in the oxidized domains. The occurrence of similar enrichments in critical elements can be expected in other similar large uranium deposits, which could be a source of these elements as by-products. Keywords: critical metals; redox-sensitive elements; red bed; metamorphite; vanadium; uranium; copper; rare earth elements; cobalt; nickel; selenium The Eureka deposit in Castell-estaó in the Catalan Pyrenees is a Cu–U–V deposit, hosted by Triassic red-bed sandstones, and classified here as a low-temperature, sandstone-hosted stratabound metamorphite U deposit. The main mineralisation is stratabound, related to coal-bearing units and produced during the Alpine deformation by migration of hydrothermal fluids. In this stage, the original sedimentary and diagenetic components (quartz and calcite, micas, hematite and locally apatite) were replaced by a complex sequence of roscoelite, fine-grained REE phosphates, sulphides and Ni–Co arsenides and sulpharsenides, Ag–Pb selenides, bismuth phases, sulphosalts and uraninite. The black shales of the Silurian sediments underlying the deposit and the nearby Carboniferous volcanoclastic rocks are interpreted as the source of the redox-sensitive elements concentrated in Eureka. The sulphur source is related to leaching of the evaporitic Keuper facies. The REE transport would be facilitated by SO4-rich solutions. The reduction of these solutions by interaction with organic matter resulted in the widespread precipitation of REE and redox-sensitive elements, including many critical metals (V, Bi, Sb, Co), whereas barite precipitated in the oxidized domains. The occurrence of similar enrichments in critical elements can be expected in other similar large uranium deposits, which could be a source of these elements as by-products. Keywords: critical metals; redox-sensitive elements; red bed; metamorphite; vanadium; uranium; copper; rare earth elements; cobalt; nickel; selenium The Eureka deposit in Castell-estaó in the Catalan Pyrenees is a Cu–U–V deposit, hosted by Triassic red-bed sandstones, and classified here as a low-temperature, sandstone-hosted stratabound metamorphite U deposit. The main mineralisation is stratabound, related to coal-bearing units and produced during the Alpine deformation by migration of hydrothermal fluids. In this stage, the original sedimentary and diagenetic components (quartz and calcite, micas, hematite and locally apatite) were replaced by a complex sequence of roscoelite, fine-grained REE phosphates, sulphides and Ni–Co arsenides and sulpharsenides, Ag–Pb selenides, bismuth phases, sulphosalts and uraninite. The black shales of the Silurian sediments underlying the deposit and the nearby Carboniferous volcanoclastic rocks are interpreted as the source of the redox-sensitive elements concentrated in Eureka. The sulphur source is related to leaching of the evaporitic Keuper facies. The REE transport would be facilitated by SO4-rich solutions. The reduction of these solutions by interaction with organic matter resulted in the widespread precipitation of REE and redox-sensitive elements, including many critical metals (V, Bi, Sb, Co), whereas barite precipitated in the oxidized domains. The occurrence of similar enrichments in critical elements can be expected in other similar large uranium deposits, which could be a source of these elements as by-products. Keywords: critical metals; redox-sensitive elements; red bed; metamorphite; vanadium; uranium; copper; rare earth elements; cobalt; nickel; selenium

A novel hydroperoxoiron(III) species [Fe III (OOH)(MeCN)(PyNMe 3 )] 2+ (3) has been generated by reaction of its ferrous precursor [Fe II (CF 3 SO 3 ) 2 (PyNMe 3 )] (1) with hydrogen peroxide at low temperatures. This species has been characterized by several spectroscopic techniques and cryospray mass spectrometry. Similar to most of the previously described low-spin hydroperoxoiron(III) compounds, 3 behaves as a sluggish oxidant and it is not kinetically competent for breaking weak C−H bonds. However, triflic acid addition to 3 causes its transformation into a much more reactive compound towards organic substrates that is capable of oxidizing unactivated C−H bonds with high stereospecificity. Stopped-flow kinetic analyses and theoretical studies provide a rationale for the observed chemistry, a triflic-acid-assisted heterolytic cleavage of the O−O bond to form a putative strongly oxidizing oxoiron(V) species. This mechanism is reminiscent to that observed in heme systems, where protonation of the hydroperoxo intermediate leads to the formation of the high-valent [(Porph . )Fe IV (O)] (Compound I) Financial support for this work was provided by the European Commission (2011-CIG-303522 to A.C., 675020-MSCA-ITN-2015-ETN to M.C.), the Spanish Ministry of Science (CTQ2015-70795-P to M.C., CTQ2016-77989-P to A.C., CTQ2014-52525-P to J.M.L., CTQ2015-65707-C2-2-P to M.G.B., and CSD2010-00065 to M.C and M.G.B.) and Generalitat de Catalunya (ICREA Academia Award to M.C. and 2014 SGR 862). The Spanish Ministry of Science is also acknowledged for a Ram n y Cajal contract to A.C. (RYC-2011–08683). The work conducted at the University of Minnesota has been supported by the US National Science Foundation (grant CHE1665391 to L.Q.). XAS data was collected at the SOLEIL synchrotron SAMBA beamline (proposal 20150413)

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2019, Tutors: Albert Figuerola Silvestre, Alexandr Shafir, Controlled photochemical generation of reactive radical species has become a powerful bond-forming tool in organic synthesis. In this project, we have performed initial and preliminary studies towards photochemical radical generation using the C-O bond of hypervalent iodine reagents. We also initiated a project (for the first time in the group) to carry out dual nickel/photoredox coupling of α-substituted C(sp3) trifluoroborates. Studies towards hypervalent iodine compounds have been successfully realized. Focusing on the first goal, the generation and the controlled transfer of ·CF2H and ·CFH2 radicals to C-H positions of activated heterocyclic substrates via homolytic I-O cleavage followed by decarboxylation process has been successfully carried out. Specifically, new hypervalent reagents have been designed and prepared in order to help prevent harmful radical side reactions. In another iodane-based approach, the synthesis of 1,8-diiodonaphthalene by homolytic bond cleavage and later decarboxylation process was assayed. For comparison, the target compound was also obtained by the diazonium salt intermediate. The adaptation of the photochemical (diradical) route to a small-scale photoreactor has proven challenging and will be continued in the group. The last goal which is the synthesis of two different Iridium photocatalyst to be applied in cross-coupling photo-redox reactions has been achieved. The photocatalyst synthesis has been successful realized in all steps, obtaining the desired pure catalysts as a crystalline yellow powder. On the other hand, the cross-coupling photo-redox products have not been obtained due to the air sensitivity of the other photocatalyst used in this process, Ni(COD)2. However, with the use of a more robust Ni complex (e.g. [glyme]NiCl2), we anticipate that this final objective could be successfully achieved in the host research group

In this paper, we present a novel polygeneration plant with carbon capture for the combined power and dimethyl ether (DME) production. The plant layout integrates a chemical looping CO2/H2O splitting (CL) unit producing syngas (CO and H2) for the DME synthesis using the exhaust gases of an oxyfuel power cycle. The primary power is generated by oxy-combustion of syngas generated by the reduction of the metal oxide in the reduction unit of the CL redox cycle with incoming natural gas. The oxyfuel power plant also generates steam for combined power production with two streams Rankine cycles. The aim of the present work is to assess the process on the basis of energy and exergetic efficiency and economic performance of the integrated CL unit for combined power and DME production. The integration proposed resulted in a production of 103 MWe and 185.6 ton/day (2.15 kg/s) of DME. The corresponding energy and exergetic efficiency was 50.2% and 45%, respectively. A discounted cash flow analysis was performed to evaluate the profitability of the process. With a carbon credit of $80/tonne, the plant would be able to meet the current electricity with carbon capture and DME prices of $50/MWh and $18/GJ respectively. The economic analysis provided information on the main economic drivers associated with the high capital investment in the process plant with individual sub-systems. The analysis highlighted the strong potential of integrating chemical looping CO2/H2O splitting for syngas production into polygeneration systems to increase the overall efficiency while reducing the cost of carbon capture.

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2019, Tutors: Albert Figuerola Silvestre, Alexandr Shafir Controlled photochemical generation of reactive radical species has become a powerful bond-forming tool in organic synthesis. In this project, we have performed initial and preliminary studies towards photochemical radical generation using the C-O bond of hypervalent iodine reagents. We also initiated a project (for the first time in the group) to carry out dual nickel/photoredox coupling of α-substituted C(sp3) trifluoroborates. Studies towards hypervalent iodine compounds have been successfully realized. Focusing on the first goal, the generation and the controlled transfer of ·CF2H and ·CFH2 radicals to C-H positions of activated heterocyclic substrates via homolytic I-O cleavage followed by decarboxylation process has been successfully carried out. Specifically, new hypervalent reagents have been designed and prepared in order to help prevent harmful radical side reactions. In another iodane-based approach, the synthesis of 1,8-diiodonaphthalene by homolytic bond cleavage and later decarboxylation process was assayed. For comparison, the target compound was also obtained by the diazonium salt intermediate. The adaptation of the photochemical (diradical) route to a small-scale photoreactor has proven challenging and will be continued in the group. The last goal which is the synthesis of two different Iridium photocatalyst to be applied in cross-coupling photo-redox reactions has been achieved. The photocatalyst synthesis has been successful realized in all steps, obtaining the desired pure catalysts as a crystalline yellow powder. On the other hand, the cross-coupling photo-redox products have not been obtained due to the air sensitivity of the other photocatalyst used in this process, Ni(COD)2. However, with the use of a more robust Ni complex (e.g. [glyme]NiCl2), we anticipate that this final objective could be successfully achieved in the host research group

The Eureka deposit in Castell-esta&oacute, in the Catalan Pyrenees is a Cu&ndash, U&ndash, V deposit, hosted by Triassic red-bed sandstones, and classified here as a low-temperature, sandstone-hosted stratabound metamorphite U deposit. The main mineralisation is stratabound, related to coal-bearing units and produced during the Alpine deformation by migration of hydrothermal fluids. In this stage, the original sedimentary and diagenetic components (quartz and calcite, micas, hematite and locally apatite) were replaced by a complex sequence of roscoelite, fine-grained REE phosphates, sulphides and Ni&ndash, Co arsenides and sulpharsenides, Ag&ndash, Pb selenides, bismuth phases, sulphosalts and uraninite. The black shales of the Silurian sediments underlying the deposit and the nearby Carboniferous volcanoclastic rocks are interpreted as the source of the redox-sensitive elements concentrated in Eureka. The sulphur source is related to leaching of the evaporitic Keuper facies. The REE transport would be facilitated by SO4-rich solutions. The reduction of these solutions by interaction with organic matter resulted in the widespread precipitation of REE and redox-sensitive elements, including many critical metals (V, Bi, Sb, Co), whereas barite precipitated in the oxidized domains. The occurrence of similar enrichments in critical elements can be expected in other similar large uranium deposits, which could be a source of these elements as by-products.

Aquaculture is a growing industry that is increasingly providing a sizable proportion of fishery products for human consumption. Dietary energy and temperature fluctuations affect fish health and may even trigger mortality, causing great losses in fish production during winter. To better understand this unproductive winter period in aquaculture, the redox status in a cultured marine species, the gilthead sea bream, was analyzed for the first time by inducing controlled temperature fluctuations and reducing dietary lipid content. Two groups of fish (by triplicate), differing in their dietary lipid content (18% vs. 14%), were subjected to 30 days at 22∘C (Pre-Cold), 50 days at 14∘C (Cold) and then 35 days at 22∘C (Recovery). Plasma and liver redox metabolites (oxidized lipid, oxidized protein and thiol groups), liver glutathione forms (total, oxidized and reduced) and liver antioxidant enzyme activities were measured. Reducing dietary lipid content did not affect gilthead sea bream growth, glutathione levels or enzyme activities, but did reduce the amount of oxidized lipids. A sustained low temperature of 14∘C showed a lack of adaptation of antioxidant enzyme activities, mainly catalase and glutathione reductase, which subsequently affected the glutathione redox cycle and caused an acute reduction in total hepatic glutathione levels, irrespective of diet. Antioxidant enzyme activities were gradually restored to their pre-cold levels, but the glutathione redox cycle was not restored to its pre-cold values during the recovery period used. Moreover, the lower lipid diet was associated with transiently increased liver oxidized protein levels. Thus, we propose that fish should be fed a low lipid diet during pre-cold and cold periods, which would reduce oxidized lipid levels without affecting fish growth, and a higher energy diet during the recovery period. Moreover, diets supplemented with antioxidants should be considered, especially during temperature recovery

Photoinduced electron transfer in transition-metal complexes linked to a fullerene moiety is of increasing interest. Recently, several stereoisomers of an Ir-complex exhibiting configurational stability at metal center, which does not undergo epimerization have been synthesized (Angew. Chem. Int. Ed. 2017, 56, 2136). The presence of multiple electron donor and acceptor sites located at opposite ends with respect to the metallic center creates the prerequisites for the formation of entirely different charge transfer (CT) states. Here we report the results of quantum mechanical calculations and detailed analysis of excited-state properties for all stereoisomers of the junction. We found that the stereoisomers demonstrate clearly different CT properties by photoexcitation. The found photo-stereospecific effects can be used to design new hybrids with a different type of photoinduced CT state, exhibiting dissimilar activity in photocatalysis.

[eng] Electron Transfer (ET) plays essential roles in crucial biological processes such as cell respiration and photosynthesis. It takes place between redox proteins and in protein complexes that display an outstanding efficiency and environmental adaptability. Although the fundamental aspects of ET processes are well understood, more experimental methods are needed to determine electronic pathways. Understanding how ET works is important not only for fundamental reasons, but also for the potential technological applications of these redox‐active nanoscale systems. The general objective of this thesis is to investigate electron transfer in redox proteins at the single molecule level. To that end, we use Electrochemical Scanning Tunneling Microscopy (ECSTM) and conductive Atomic Force Microscopy (cAFM), excellent tools to study electronic materials and redox molecules including proteins. In this thesis, we focused on two redox protein systems: azurin, a small electron carrier protein and photosystem I, a light‐sensitive oxidoreductase protein complex. In azurin, we studied the protein conductance as a function of its redox state and location on the protein surface, and the effect of technical parameters such as the contact properties between azurin and the metal electrodes, and the mechanical force applied in such contact. For that we adapted our ECSTM setup for an alternating current method often used in ultrahigh vacuum (UHV) STMs. We also worked in the development of a methodology that combines AFM‐based single‐molecule force measurements with single‐molecule electrical measurements, while working in an electrochemically controlled environment. These techniques can lead to a more detailed description of the ET pathways, and to a deeper understanding of the complex relation between the structure of redox proteins and their electronic properties. In photosystem I, developed a method to immobilize complexes on a substrate suitable for ECSTM imaging and spectroscopy, atomically flat gold. In these conditions, we characterized photosystem I by imaging and spectroscopy, and evaluated its conductance and distance‐decay properties in a wide range of biologically relevant electrochemical potentials. The characterization of conduction pathways in redox proteins at the nanoscale would enable important advances in biochemistry and would cause a high impact in the field of nanotechnology., [spa] La transferencia de electrones (ET) desempeña papeles esenciales en procesos biológicos cruciales como la respiración celular y la fotosíntesis. Tiene lugar inter‐ e intra‐ proteínas redox y en complejos de proteínas que muestran una eficiencia excepcional y gran capacidad de adaptación ambiental. Aunque los aspectos fundamentales de los procesos de ET se han estudiado en profundidad, se necesitan más métodos experimentales para determinar las vías electrónicas de ET. La comprensión de cómo funciona la ET es importante no sólo por razones fundamentales, sino también por las potenciales aplicaciones tecnológicas de estos sistemas redox nanoscópicos. El objetivo general de esta tesis es investigar la transferencia de electrones en las proteínas redox a nivel de molécula individual. Para ello utilizamos la Microscopía de Túnel Electroquímico (ECSTM) y la Microscopía de Fuerza Atómica Conductor (cAFM), que son excelentes herramientas para estudiar materiales electrónicos y moléculas redox, incluyendo proteínas. En esta tesis, nos centramos en dos sistemas de proteínas redox: azurina, una pequeña proteína portadora de electrones y el fotosistema I, un complejo de proteína oxidorreductasa sensible a la luz. En el estudio de la azurina, estudiamos la conductancia de las proteínas en función de su estado redox y el efecto de parámetros técnicos como las propiedades de contacto entre la azurina y los electrodos metálicos, y la fuerza mecánica aplicada en dicho contacto. Para ello hemos adaptado nuestra configuración de ECSTM para un método de corriente alterna a menudo utilizado en Microscopía de Túnel de ultra alto vacío (UHV‐STM). También trabajamos en el desarrollo de una metodología que combina medidas de fuerza de una sola molécula basadas en AFM con medidas eléctricas, mientras trabajamos en un ambiente controlado electroquímicamente. Estas técnicas pueden conducir a una comprensión más profunda de las vías de ET y de la compleja relación entre la estructura de las proteínas redox y sus propiedades electrónicas. En el estudio del fotosistema I, desarrollamos un método para inmovilizar complejos sobre un sustrato adecuado para la obtención de imágenes y espectroscopía con ECSTM, oro atómicamente plano. En estas condiciones, caracterizamos el fotosistema I mediante imágenes y espectroscopia, y evaluamos sus propiedades de conductancia y sus parámetros de decaimiento de la corriente con la distancia, en una amplia gama de potenciales electroquímicos biológicamente relevantes. La caracterización de las vías de conducción en las proteínas redox a escala nanométrica puede permitir importantes avances en bioquímica y causar un alto impacto en el campo de la nanotecnología.

[eng] Electron Transfer (ET) is undoubtedly one of the most important processes in life. Molecularly well-defined ET pathways in complex protein ensembles play a vital role in biological processes such as cell respiration or photosynthesis. The fundamental understanding of ET processes in biology is important not only to understand such key natural processes but also to advance in the design of biomolecule/electrode interfaces for Bioelectronic applications. The development of new techniques such as scanning probe microscopies (SPM) played a key role. In particular, the electrochemical scanning tunnelling microscopy (EC-STM) has been exploited to in situ monitor the ET rate as a function of the applied potential of individual metalloproteins immobilized on an Au electrode thanks to the single-molecule spatial resolution and the electrochemical gate capabilities. Azurin from Pseudomonas aeruginosa is a widely studied redox protein model both in bulk and at the single molecule level. Its globular structure contains a coordinated copper ion, which makes the protein capable of exchanging electrons by switching its redox state (Cu I/II) and supports its role as a soluble electron carrier in the respiratory chain of bacteria. In this thesis, we will show our advances on the design and characterization of single-protein devices using a Cu-Azurin metalloprotein model. We have demonstrated transistor like-behaviour in an electrochemically-gated single-protein wire that operates at very low voltages thanks to the Cu-Azurin redox properties. It was demonstrated that the conductance varies depending on the redox state of the Cu centre, having its maximum value at the redox-midpoint. We have also analysed the spontaneous formation of single-Azurin electrical contacts through the monitored current when the two ECSTM electrodes were placed at a fixed distance. Discrete switching events for the conductance were observed, whose frequency depends on the applied electrochemical conditions and, therefore, they were univocally ascribed to discrete changes in the redox state of the trapped protein. In order to tailor the charge transport behaviour of the single-protein wire, we have synthesized several mutants of the protein by exploiting point-site bioengineering schemes at different positions of the protein second coordination sphere. Our results show that we can rationally change the transport mechanism of the single-protein device by studying the effect of the specific residue modification on the particular ET pathways in the protein backbone., [spa] La transferencia de electrones (ET) es uno de los procesos más importantes de la vida. La comprensión fundamental de los procesos de ET en biología es importante no sólo para comprender tales procesos naturales claves, sino también para avanzar en el diseño de interfaces biomolécula / electrodo para aplicaciones bioelectrónicas. En particular, se ha explotado la microscopía de efecto túnel con control electroquímico (EC-STM) para monitorizar in situ la constante de ET en función del potencial aplicado de las metaloproteínas. La Azurina de Pseudomonas aeruginosa es un modelo de proteína redox ampliamente estudiado, tanto en ‘bulk’ como a nivel de una sola proteina. Su estructura globular contiene un ion de cobre coordinado, que hace que la proteína sea capaz de intercambiar electrones cambiando su estado redox (Cu I/II). Este ion es el responsable de su rol como portador de electrones en la cadena respiratoria de las bacterias. En esta tesis, mostraremos nuestros avances en el diseño y caracterización de dispositivos de una sola proteína utilizando un modelo de metaloproteína Cu-Azurin. Hemos demostrado un comportamiento similar a un transistor en un hilo electroquímico de una sola proteína que funciona a muy bajos voltajes gracias a las propiedades redox de Cu-Azurin. Se demostró que la conductancia varía dependiendo del estado redox del centro de Cu, teniendo su valor máximo en el punto medio redox. También hemos analizado la formación espontánea de los contactos eléctricos de Azurin única a través de la corriente monitorizada cuando los dos electrodos ECSTM se colocaron a una distancia fija. Se observaron eventos discretos de conmutación para la conductancia, cuya frecuencia depende de las condiciones electroquímicas aplicadas y, por lo tanto, se atribuyeron unívocamente cambios discretos en el estado redox de la proteína atrapada. Con el fin de adaptar el comportamiento de transporte de carga de la unión uniproteica, hemos sintetizado varios mutantes de la misma proteína mediante bioingeniería en diferentes posiciones de la proteína. Nuestros resultados muestran que podemos cambiar racionalmente el mecanismo de transporte del dispositivo de una sola proteína mediante el estudio del efecto de la modificación de residuos específicos en las vías ET particular en el esqueleto de la proteína.

[cat] El malbaratament dels productes frescos suposa la pèrdua de fins a un 45% dels fruits i vegetals. El canvi global i el previst increment de la freqüència de fenòmens meteorològics extrems representaran una major pressió a la producció i la cadena logística des del camp fins al consumidor, especialment als països en desenvolupament on la cadena del fred no sempre es pot mantenir i les pèrdues poden representar una fracció encara major de la collita. La senescència post-collita i els estressos associats limiten la longevitat comercial, però també la qualitat organolèptica i valor nutricional dels vegetals i productes frescos. Una millor comprensió d'aquests processos crea oportunitats per a una millor gestió i per dirigir programes de millora. Després de la collita, l’exposició controlada a estressos abiòtics i/o aplicacions exògenes de fitohormones i reguladors del creixement pot millorar característiques nutricèutiques, organolèptiques i de longevitat comercial. En aquesta tesi s’han desenvolupat noves metodologies per combinar trets fisiològics, perfils hormonals i bioquímics, i eines transcriptòmiques per caracteritzar millor els processos de senescència d'òrgans. Permetent així el disseny d’estratègies biotecnològiques per millorar la qualitat i/o longevitat de productes frescos, tot descrivint els efectes subjacents d'aquesta manipulació en la fisiologia de la post-collita i la maduració de fruits. Els resultats suggereixen el potencial per manipular la senyalització per àcid abscísic (ABA) amb aplicacions d’ABA i/o pirabactina (pyrabactin) per millorar la qualitat post-collita de les verdures de fulla verda (Brassica oleracea var capitata) emmagatzemades a temperatura ambient (Capítol 3) i per millorar el contingut de vitamina C i E de fruits de gerdera (Rubus idaeus; Capítols 1 i 2); i l’estudi i caracterització de la senescència floral post-collita de flors insensibles a l’etilè (Lilium, Iris) i el potencial d’aplicacions de melatonina per millorar la longevitat post-collita de Lilium (Capítol 1, Apèndix 1). S’observà com els processos de senescència de fulles i flors, i de maduració de fruits, comparteixen característiques fisiològiques i de la seva regulació hormonal i redox, resultant l’ABA un important regulador d’aquests processos., [eng] Food waste and loss represents 45% of fruits and vegetables production. Global change and the forecasted increase in the frequency of extreme weather events will further strain the production and the logistic chain from the field to the consumer, especially in the developing world where the cold chain cannot always be properly maintained. Post-harvest senescence and associated stresses limit longevity, but also the organoleptic quality and nutritional value of fresh products. Improved understanding of these processes creates options for better management and to inform breeding programs. After harvest, controlled exposure to abiotic stresses and/or exogenous phytohormones can enhance nutraceutical, organoleptic and commercial longevity traits. In this Thesis new methodologies to combine physiological features, hormonal and biochemical profiles, and transcriptomic tools have been developed to better characterise organ senescence processes. Thus, allowing the design of biotechnological strategies to improve the quality and/or longevity of fresh products, describing the underlying effects of this manipulation on post-harvest physiology and fruit maturation. The results suggest the potential to manipulate ABA signalling through ABA and/or pyrabactin applications to improve the post-harvest quality of green leafy vegetables (Brassica oleracea var capitata) stored at room temperature (Chapter 3) and to improve vitamin C and E content of raspberry fruits (Rubus idaeus; Chapters 1 and 2); and the characterization of the post-harvest senescence of ethylene-insensitive flowers (Lilium, Iris) and the potential of melatonin applications to improve Lilium post-harvest longevity (Chapter 1, Appendix 1). It was observed how the processes of leaf and flower senescence, and of fruit ripening, share physiological characteristics and its hormonal and redox regulation, resulting in ABA being an important regulator of these processes.

The addition of some fat co- and by-products to feeds is usual nowadays; however, the regulations of their use are not always clear and vary between countries. For instance, the use of recycled cooking oils is not allowed in the European Union, but they are used in other countries. However, oils recovered from industrial frying processes could show satisfactory quality for this purpose. Here we studied the effects of including oils recovered from the frying industry in rabbit and chicken feeds (at 30 and 60 g/kg, respectively) on the fatty acid (FA) and tocol (tocopherol + tocotrienol) compositon of meat, liver and plasma, and on their oxidative stability. Three dietary treatments (replicated eight times) were compared: fresh non-used oil (LOX); oil discarded from the frying industry, having a high content of secondary oxidation compounds (HOX); and an intermediate level (MOX) obtained by mixing 50 : 50 of LOX and HOX. The FA composition of oil diets and tissues was assessed by GC, their tocol content by HPLC, the thiobarbituric acid value was used to assess tissue oxidation status, and the ferrous oxidation-xylenol orange method was used to assess the susceptibility of tissues to oxidation. Our results indicate that FA composition of rabbit and chicken meat, liver and plasma was scarcely altered by the addition of recovered frying oils to feed. Differences were encountered in the FA composition between species, which might be attributed mainly to differences in the FA digestion, absorption and metabolism between species, and to some physiological dietary factors (i.e. coprophagy in rabbits that involves fermentation with FA structure modification). The α-tocopherol (αT) content of tissues was reduced in response to the lower αT content in the recovered frying oil. Differences in the content of other tocols were encountered between chickens and rabbits, which might be attributable to the different tocol composition of their feeds, as well as to species differences in the digestion and metabolism of tocols. Tissue oxidation and susceptibility to oxidation were in general low and were not greatly affected by the degree of oxidation of the oil added to the feeds. The relative content of polyunsaturated fatty acids/αT in these types of samples would explain the differences observed between species in the susceptibility of each tissue to oxidation. According to our results, oils recovered from the frying industry could be useful for feed uses.

This research evaluates the effects of adding a tocopherol mix (0 or 200 mg/kg), two nitrite sources (sodium nitrite or a nitrate-rich vegetable concentrate) and the use of Staphylococcus carnosus together with fermentation types that varied in temperature (12 h at 4 ℃ or 16 ℃) on different quality parameters and acceptability of cooked cured sausages after vacuum packing and storage at 4 ℃ for 120 days. In the presence of S. carnosus, residual nitrate and nitrite levels were reduced. Sausages containing vegetable concentrates and without S. carnosus resulted in higher amounts of residual nitrate and lower curing efficiency. The lowest values in redness and acceptability were observed in those sausages without starter cultures. The addition of tocopherols had no effect on oxidative status and susceptibility to oxidation. However, the highest amount of hydroperoxides was related with nitrite decreased formation. Overall, vegetable concentrates can be used as curing agents if fermentation with a nitrate-reducing starter culture is allowed.

Fortification of food products with iron is a common strategy to prevent or overcome iron deficiency. However, any form of iron is a pro-oxidant and its addition will cause off-flavours and reduce a product's shelf life. A highly bioavailable heme iron ingredient was selected to fortify a chocolate cream used to fill sandwich-type cookies. Two different strategies were assessed for avoiding the heme iron catalytic effect on lipid oxidation: ascorbyl palmitate addition and co-spray-drying of heme iron with calcium caseinate. Oxidation development and sensory acceptability were monitored in the cookies over one-year of storage at room temperature in the dark. The addition of ascorbyl palmitate provided protection against oxidation and loss of tocopherols and tocotrienols during the preparation of cookies. In general, ascorbyl palmitate, either alone or in combination with the co-spray-dried heme iron, prevented primary oxidation and hexanal formation during storage. The combination of both strategies resulted in cookies that were acceptable from a sensory point of view after 1year of storage.

The plant pathogenic bacterium Ralstonia solanacearum injects more than 70 effector proteins (virulence factors) into the host plant cells via the needle-like structure of a type III secretion system. The type III secretion system effector proteins manipulate host regulatory networks to suppress defense responses with diverse molecular activities. Uncovering the molecular function of these effectors is essential for a mechanistic understanding of R. solanacearum pathogenicity. However, few of the effectors from R. solanacearum have been functionally characterized, and their plant targets remain largely unknown. Here, we show that the ChaC domain-containing effector RipAY/RSp1022 from R. solanacearum exhibits γ-glutamyl cyclotransferase (GGCT) activity to degrade the major intracellular redox buffer, glutathione. Heterologous expression of RipAY, but not other ChaC family proteins conserved in various organisms, caused growth inhibition of yeast Saccharomyces cerevisiae, and the intracellular glutathione level was decreased to ∼30% of the normal level following expression of RipAY in yeast. Although active site mutants of GGCT activity were non-toxic, the addition of glutathione did not reverse the toxicity, suggesting that the toxicity might be a consequence of activity against other γ-glutamyl compounds. Intriguingly, RipAY protein purified from a bacterial expression system did not exhibit any GGCT activity, whereas it exhibited robust GGCT activity upon its interaction with eukaryotic thioredoxins, which are important for intracellular redox homeostasis during bacterial infection in plants. Our results suggest that RipAY has evolved to sense the host intracellular redox environment, which triggers its enzymatic activity to create a favorable environment for R. solanacearum infection., This work was supported by Japan Society for the Promotion of Science KAKENHI Grants 22580095 and 25450104 and also, in part, by the General Research Grant of the Institute of Fermentation, Osaka.

CH3OH on a single-crystal rutile TiO2(110) surface is a widely studied model system for heterogeneous photocatalysis. Using spin-polarized density functional theory with a hybrid functional (HSE06), we study the photocatalytic oxidation of CH3OH adsorbed at a coordinately unsaturated Ti site as an excited-state process with triplet spin multiplicity. The oxidation to CH2O is stepwise and involves a CH3O intermediate. The first O–H dissociation step follows an excitonic interfacial proton-coupled electron transfer mechanism where the hole–electron (h–e) pair generated during the excitation is bound, and the h is transferred to the adsorbate. The O–H dissociation paths associated with other h–e pairs are unreactive, and the moderate experimental efficiency is due to the different reactivity of the h–e pairs. The excited-state CH3O intermediate further deactivates through a seam of intersection between the ground and excited states. It can follow three different paths, regeneration of adsorbed CH3OH or formation of the ground-state CH3O anion or an adsorbed CH2O radical anion. The third channel corresponds to photochemical CH2O formation from CH3OH, where a single photon induces one electron oxidation and transfer of two protons. These results expand the current view on the photocatalysis of CH3OH on TiO2(110) by highlighting the role of excitons and showing that adsorbed CH3OH may also be an active species in the photocatalytic oxidation to CH2O., We acknowledge financial support from Spanish Ministerio de Economia y Competitividad (FIS2012-37549-C05-02, UNGI10-4E-801, RYC-2011-09582, CTQ2015-69363-P), Generalitat de Catalunya (2014SGR-301, 2014SGR-1202, XRQTC)

Fortification of food products with non-heme or heme iron is a common strategy to overcome nutritional iron deficiency. Heme iron is highly bioavailable but it promotes oxidation, as do other iron forms. Palm oil is widely used in the formulation of bakery products and chocolate fillings. The work reported here aims to delay the onset of oxidation of a palm oil matrix fortified with heme iron, as a model for bakery products, through the use of ascorbyl palmitate (0 and 400 mg/kg) and the co-spray-drying of the heme iron with calcium caseinate in two ratios (heme iron concentrate:caseinate, 2:1 and 1:1, w/w). Primary (peroxide value and lipid hydroperoxide content) and secondary (p-anisidine value and hexanal content) oxidation were measured over one year of storage at room temperature in the dark. The combination of ascorbyl palmitate at 400 mg/kg and the co-spray-dried heme iron in a 1:1 ratio was the treatment that best protected iron fortified samples from oxidation during the storage time. Practical applications: Food fortification with iron has been suggested as a good strategy for overcoming iron deficiency. In this study, a heme iron ingredient has been selected due to its higher bioavailability than inorganic iron forms. Nevertheless, as other iron forms, heme iron is a potent pro-oxidant, which may affect the nutritional value, the sensory properties and shelf life of the fortified product. Thus, in this study the co-spray-drying of the heme iron with several coatings was assessed in order to reduce its pro-oxidant activity. The different heme irons were mixed with palm oil, which is a fat widely used in bakery. The combination of co-spray-dried heme iron and ascorbyl palmitate delayed the onset of oxidation, which demonstrates its effectiveness in future iron fortified bakery products. Palm oil is widely used in the formulation of bakery products and chocolate fillings. Therefore, this matrix can be a useful model for iron fortification in bakery products. In a preliminary study with heme iron fortified sunflower oil, the co-spray-drying of heme iron with different coating agents delayed the oxidation onset during accelerated storage at 60°C (see the figure).The combination of ascorbyl palmitate and the co-spray-drying of heme iron with calcium caseinate at 1:1 ratio (CAS 1:1) prevented oxidation of a heme iron fortified palm oil during storage at room temperature in the dark for one year.

In this work, we present the synthesis, spectroscopic and redox characterization of a new chromophore‐catalyst dyad ruthenium compound, (Rup‐Ruc‐Cl), linked by a bridging polypiridyl ligand (trpy‐ph‐trpy). A preliminary study of it catalytic behaviour in the photo‐oxidation of 1‐ phenylethanol in aqueous medium is also presented. The system consists of a catalyst based on a ruthenium chlorocomplex [RuCl (R‐trpy)(bpy)] 2+ (RuII‐Cl, Ruc) and a chromophore which absorbs light in the visible spectrum, [Ru (trpy)(R‐trpy)] 2+(Rup). Both compounds share the bridging ligand (trpy‐ph‐trpy). Two synthetic pathways have been carried out to obtain this compound : 1) First, it has been carried out the synthesis of catalyst [RuIICl(trpy‐ph‐trpy)(bpy)]+ (Ruc‐Cl) [3] by the reaction of bridging ligand (trpy‐ph‐trpy) with cis (Cl),cis (S)‐[RuCl2(DMSO‐S)2] [2]. Then, the complex Ruc IICl [3] reacts with [RuIII(trpy)Cl3] [4], to obtain the final complex Rup‐Ruc‐Cl [5]. In another synthetic patway, 2), first, it is carried out the synthesis of chromophore [RuII(trpy)(trpy‐ph‐trpy)]2+(Rup) [7] by the reaction of [RuII(trpy)(DMSO)Cl2] [6] with the bridging (trpy‐ph‐trpy) ligand. Then, compound [7] reacts with cis(Cl),cis(S)‐ [RuIICl2(bpy)(DMSO‐S)2] [2] to obtain the final complex Rup‐Ruc‐Cl [5]. The characterization of complexes have been carried out in solid state through elemental analysis and infrared spectroscopy (IR) and in solution by spectroscopic techniques such as nuclear magnetic resonance (NMR) and ultraviolet visible (UV‐Vis).The redox characterization has been done by cyclic voltammetry (CV). Finally, it has been evaluated the catalytic activity of the compound Rup‐Ruc‐Cl [5], in the photooxidation reaction of 1‐phenylethanol in aqueous medium

Carnitine palmitoyltransferase 1 (CPT1) catalyzes the first step in long-chain fatty acid import into mitochondria, and it is believed to be rate limiting for beta-oxidation of fatty acids. However, in muscle, other proteins may collaborate with CPT1. Fatty acid translocase/CD36 (FAT/CD36) may interact with CPT1 and contribute to fatty acid import into mitochondria in muscle. Here, we demonstrate that another membrane-bound fatty acid binding protein, fatty acid transport protein 1 (FATP1), collaborates with CPT1 for fatty acid import into mitochondria. Overexpression of FATP1 using adenovirus in L6E9 myotubes increased both fatty acid oxidation and palmitate esterification into triacylglycerides. Moreover, immunocytochemistry assays in transfected L6E9 myotubes showed that FATP1 was present in mitochondria and coimmunoprecipitated with CPT1 in L6E9 myotubes and rat skeletal muscle in vivo. The cooverexpression of FATP1 and CPT1 also enhanced mitochondrial fatty acid oxidation, similar to the cooverexpression of FAT/CD36 and CPT1. However, etomoxir, an irreversible inhibitor of CPT1, blocked all these effects. These data reveal that FATP1, like FAT/CD36, is associated with mitochondria and has a role in mitochondrial oxidation of fatty acids.

Màster Oficial en Física Avançada. Facultat de Física, Universitat de Barcelona, Curs: 2015, Tutors: Felix Ritort i Anna Alemany, We investigate the unfolding and folding processes of redox protein Flavodoxin under the action of mechanical forces at the single molecule level using force spectroscopy methods with optical tweezers. Previous bulk studies have provided valuable information about the structure of the folded and unfolded states, and pointed out the existence intermediate states along the unfolding and folding pathways. However direct evidence about the existence of such kinetic intermediates and their lifetimes is still missing. Here we pull molecular constructs of the protein Flavodoxin flanked by double stranded DNA linkers tethered to micron-sized beads with optical tweezers to mechanically unfold the protein. The distributions of rupture forces have been characterized and intermediate states have been found along the unfolding and folding pathways. Moreover, the molecular free energy landscape of the protein has been characterized from the unfolding kinetics using the Bell-Evans model and an estimate of the free energy of formation of the protein has been extracted using the Crooks fluctuation theorem

The metallacarborane [3,3'-Co(1,2-closo-C2B9H11)2](-) has been synthesized. This species allows the formation of redox couples in which both partners are negatively charged. The E1/2 potential can be tuned by adjusting the nature and number of substituents on B and C. The octaiodinated species [3,3'-Co(1,2-closo-C2B9H7I4)2](-) is the most favorable, as it is isolatable and stable in air. A DFT study on stability and redox potentials of complexes has been performed.

Oxidative modifications in proteins have been traditionally considered as hallmarks of damage by oxidative stress and aging. However, oxidants can generate a huge variety of reversible and irreversible modifications in amino acid side chains as well as in the protein backbones, and these post-translational modifications can contribute to the activation of signal transduction pathways, and also mediate the toxicity of oxidants. Among the reversible modifications, the most relevant ones are those arising from cysteine oxidation. Thus, formation of sulfenic acid or disulfide bonds is known to occur in many enzymes as part of their catalytic cycles, and it also participates in the activation of signaling cascades. Furthermore, these reversible modifications have been usually attributed with a protective role, since they may prevent the formation of irreversible damage by scavenging reactive oxygen species. Among irreversible modifications, protein carbonyl formation has been linked to damage and death, since it cannot be repaired and can lead to protein loss-of-function and to the formation of protein aggregates. This review is aimed at researchers interested on the biological consequences of oxidative stress, both at the level of signaling and toxicity. Here we are providing a concise overview on current mass-spectrometry-based methodologies to detect reversible cysteine oxidation and irreversible protein carbonyl formation in proteomes. We do not pretend to impose any of the different methodologies, but rather to provide an objective catwalk on published gel-free approaches to detect those two types of modifications, from a biologist's point of view. This work was supported by the Spanish Ministry of Science and Innovation (BFU2012-32045), PLAN E and FEDER, and by SGR2009-195 from Generalitat de Catalunya (Spain) to E.H. J.A. and E. H. are recipients of ICREA Academia Awards (Generalitat de Catalunya).

A fluorometric method for the determination of hydroperoxides (HP) in edible oils and fats using the reagent diphenyl-1-pyrenylphosphine (DPPP) was developed and validated. Two solvent media containing 100% butanol or a mixture of chloroform/methanol (2:1, v/v) can be used to solubilise lipid samples. Regardless of the solvent used to solubilise the sample, the DPPP method was precise, accurate, sensitive and easy to perform. The HP content of 43 oil and fat samples was determined and the results were compared with those obtained by means of the AOCS Official Method for the determination of peroxide value (PV) and the ferrous oxidation-xylenol orange (FOX) method. The proposed method not only correlates well with the PV and FOX methods, but also presents some advantages such as requiring low sample and solvent amounts and being suitable for high-throughput sample analysis. © 2014 Elsevier Ltd. All rights reserved.

Both photo-Fenton oxidation and the combination of aerobic sequencing batch reactor (SBR) + photo-Fenton processes were investigated in a bench-scale study to degrade and reuse a real textile wastewater with Total Organic Carbon (TOC) = 390 mg L −1 , Chemical Oxygen Demand (COD) = 1560 mg L −1 O 2 and Escherichia coli = 80000 CFU mL −1 in further dyeing processes. The independent variables considered for the evaluation of the oxidative process were temperature, H 2 O 2 and Fe (II) concentrations. Required treated water qualities were determined by both RD 1620/2007 (Spanish Normative for wastewater reclamation and reuse) and specific water qualities for internal reuse. The best results were obtained when applying photo-Fenton process as a polishing step, where previous aerobic SBR under 1 day hydraulic retention time (HRT), gave 75% TOC reduction after 25 cycles. The further photo-Fenton process coupled under: ([Fe (II)] = 66.5 mg L −1 ; [H 2 O 2 ] = 1518 mg L −1 ; T = 25 °C and pH = 2.7) conditions, achieved final COD and TOC reductions of 97 and 95% respectively. E. coli was fully removed according to specific normative. Finally, in order to accomplish specific water qualities for 100% internal reuse, resultant water was further conditioned by reverse osmosis and reused in bench-scale simulated dyeing processes, providing similar dyeing results in terms of K / S than those obtained by using fresh water.

This work focuses on the use of Fenton reagent and UV-irradiation, in a lab-scale experiment, for the treatment of real dye wastewater coming from a Spanish textile manufacturer. Response surface methodology and a 2 3 factorial design were used to evaluate the effects of the three independent variables considered for the optimization of the oxidative process: temperature, Fe (II) and H 2 O 2 concentrations, for a textile wastewater generated during a dyeing process with chemical oxygen demand of 1705 mg L −1 O 2 at pH = 3. Wastewater degradation was followed in terms of chemical oxygen demand reduction. In the optimization, the correlation coefficients for the model ( R 2 ) were 0.985 and 0.990 for Fenton and photo-Fenton treatments respectively. Optimum reaction conditions at pH = 3 and temperature = 298 K were [H 2 O 2 ] = 73.5 mM and [Fe(II)] = 1.79 mM. The combination of Fenton, Fenton-like and photon-Fenton reactions has been proved to be highly effective for the treatment of such a type of wastewaters, and several advantages for this technique arise from the study. Under optimum conditions, 120 min of treatment resulted in a 62.9% and 76.3% reduction in chemical oxygen demand after Fenton and photo-Fenton treatments respectively.

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2014, Tutors: Dr. Pere Lluís Cabot i Dr. Pedro Gómez Romero, Redox Flow Batteries (RFBs) store energy in electroactive solutions stowed outside the electrochemical cells and are strong candidates to serve as load-leveling devices contributing to the development of smart grids and to offset the intermittency of renewable energy sources. Current RFBs use aqueous solutions of electroactive species1 (i.e. aqueous vanadium solutions, max conc. 2M) whose limited solubility limits in turn the energy density of the systems. In this work quinones are proposed as electroactive species to be explored as the main components in molten fluxes or in concentrated organic fluids. This approach would increase considerably the concentration of electroactive species eventually leading to a competitive alternative to vanadium solutions by providing increased voltage range, specific capacity and energy density. Quinones are known to have an electrochemical reversible process between quinone and hydroquinone, with good kinetics and a high electrochemical equivalent2 (two electrons per mole of quinone). Our work has centered on the initial and preliminary studies of electroactivity of simple quinones in organic media to determine their solubility, electroactivity, feasible voltage range and redox processes with different electrodes and electrolytes.

Treball Final de Grau en Química. Codi: QU0943. Curs: 2014/2015 Transition metal complexes with 1,2-dithiolenes are a subject of high research interest as a consequence of their rich redox chemistry, versatility in the coordination modes, biological models1,2, as well as their well-known magnetic and electrical conducting properties. Dithiolene ligands have more than one resonant form: dianionic, radical monoanionic and neutral; and the oxidation state assignment of the metal is sometimes ambiguous in these complexes. For this reason, dithiolene ligands are considered as non-innocent. As expected, the dithione form is not feasible in aromatic dithiolenes. Bis(dithiolene) complexes possess an extended electronically delocalized core comprising the central metal, the four sulphurs and the carbon-carbon units.4 Delocalization can be further extended by functionalization of the ligand. This delocalization can lead to a number of important properties: Electrochemical behavior often which one or more reversible redox processes, Low energy absorption in the visible or NIR region, distribution of the frontier orbitals over much, or all, of the molecules. In most cases, a planar arrangement of the complex with a variety of central metals. Examples include Ni, Pd, Pt, Co, Fe, Au and Cu.  The large sulphur atoms compose part of the delocalized core and as such can mediate intermolecular interactions.