BACKGROUND: This study was designed to evaluate and compare antioxidant capacity and radical scavenging activity of naringin and its aglycone by different in vitro assays. The effects of flavanones ...on lipid peroxidation, glutathione (GSH) oxidation and DNA cleavage were also assessed.RESULTS: The results showed that naringenin exhibited higher antioxidant capacity and hydroxyl and superoxide radical scavenger efficiency than naringin. Our results evidenced that glycosylation attenuated the efficiency in inhibiting the enzyme xanthine oxidase and the aglycone could act like a more active chelator of metallic ions than the glycoside. Additionally, naringenin showed a greater effectiveness in the protection against oxidative damage to lipids in a dose-dependent manner. Both flavanones were equally effective in reducing DNA damage. However, they show no protective effect on oxidation of GSH.CONCLUSION: The data obtained support the importance of characterizing the ratio naringin/naringenin in foods when they are evaluated for their health benefits.
The integration of environmental, social and governance (ESG) criteria into the evaluation process of assets is a theme that is widely accepted among socially responsible investors. In this process, ...however, the integration of investors’ preferences has not been adequately developed. The challenge is to integrate the preferences of heterogeneous investors—not only conventional investors but also investors who are particularly sensitive to sustainability issues (socially responsible investors)—considering that socially responsible investors are not necessarily homogeneous. This paper attempts to address this challenge by developing a methodological approach based on an application of fuzzy multicriteria decision-making methods (MCDM) to integrate ESG investors’ preferences, as jointly considered. Because investors’ preferences may vary depending on which material aspects are considered within a sector, this study has been tested using clothing-sector data. Results confirm the usefulness of the methodological approach proposed for a proper generation of a ‘commercial solution’ that integrates the preferences of various investors and simultaneously is consistent with individually defined preferences.
•Multiple investors’ ESG preferences were integrated into sustainable investment.•The integration was performed through a fuzzy TOPSIS MCDM.•MCDM allows the generation of more accurate investment portfolios.•Institutional investors can use it to further a better engagement with stakeholders.
Environmental, social, and governance (ESG) rating agencies, acting as relevant financial market actors, should take a stand on working towards achieving a more sustainable development. In this ...context, the objective of this paper is, on the one hand, to understand how criteria used by ESG rating agencies in their assessment processes have evolved over the last ten years and, on the other hand, to analyze whether ESG rating agencies are contributing to fostering sustainable development by the inclusion of sustainability principles into their assessment processes and practices according to the ESG criteria. This research is based on a comparative descriptive analysis of the public information provided by the most representative ESG rating and information provider agencies in the financial market in two periods: 2008 and 2018. The findings show that ESG rating agencies have integrated new criteria into their assessment models to measure corporate performance more accurately and robustly in order to respond to new global challenges. However, a deep analysis of the criteria also shows that ESG rating agencies do not fully integrate sustainability principles into the corporate sustainability assessment process.
PURPOSE OF REVIEWNuts in general and walnuts in particular are in the limelight for the association of their consumption with improved health outcomes. Walnuts have an optimal composition in ...bioactive nutrients and recent clinical and experimental studies have uncovered a number of beneficial effects of walnut micronutrients, working in isolation or in concert, on metabolic pathways and clinical outcomes that make this review timely and relevant.
RECENT FINDINGSAlpha-linolenic acid, a critical walnut component, is metabolized into bioactive oxylipins, has been shown to protect microglial cells from inflammation, and is associated with lower fatal myocardial infarction rates through a putative antiarrhythmic effect. Phytosterols relate to the cholesterol-lowering effect of nut consumption. Nonsodium minerals are associated with better cardiometabolic health. Walnut phytomelatonin has anticancer effects that are shared by the main walnut polyphenols and their metabolites, ellagitannins and urolithins, respectively.
SUMMARYThis review highlights new evidence on the health-promoting properties of walnuts and their main micronutrient components. The conclusion is that walnuts are optimal healthful foods.
In the framework of optoelectronic luminescent materials, non-radiative decay mechanisms are relevant to interpret efficiency losses. These radiationless processes are herein studied theoretically ...for a series of stilbenoid derivatives, including distyrylbenzene (DSB) and cyano-substituted distyrylbenzene (DCS) molecules in vacuo . Given the difficulties of excited-state reaction path determinations, a simplified computational strategy is defined based on the exploration of the potential energy surfaces (PES) along the elongation, twisting, and pyramidalization of the vinyl bonds. For such exploration, density functional theory (DFT), time-dependent (TD)DFT, and complete-active-space self-consistent field/complete-active-space second-order perturbation theory (CASSCF/CASPT2) are combined. The strategy is firstly benchmarked for ethene, styrene, and stilbene; next it is applied to DSB and representative DCS molecules. Two energy descriptors are derived from the approximated PES, the Franck–Condon energy and the energy gap at the elongated, twisted, and pyramidalized structures. These energy descriptors correlate fairly well with the non-radiative decay rates, which validates our computational strategy. Ultimately, this strategy may be applied to predict the luminescence behavior in related compounds.
•Manganese-iron mixed oxide was tested in chemical looping units burning syngas and coal.•Optimal preparation to achieve high reactivity, mechanical strength and magnetic behavior.•Oxygen uncoupling ...was lost when adequate mechanical properties were obtained.•Improved performance was achieved in comparison with other iron-based materials.
Synthetic manganese-iron mixed oxides are considered promising materials to be used as oxygen carriers for Chemical Looping Combustion of coal with carbon dioxide capture at low cost. The aim of this work was to evaluate a manganese-iron mixed oxide material with a manganese to iron molar ratio of 0.77:0.23 as oxygen carrier for coal combustion by means of chemical looping processes, including both ex-situ and in-situ gasification of coal. The preparation method -spray drying followed by calcination- was optimized in order to produce particles with high reactivity and mechanical strength. The material was studied in two continuously operated facilities designed to burn either gaseous or solid fuels. While full combustion was achieved burning syngas, showing the feasibility of the use of this material considering the ex-situ gasification process. Coal combustion efficiency by in-situ gasification process was improved in comparison with other previously tested low-cost materials such as ilmenite and iron ore. Moreover, the oxygen carrier particles showed an interesting magnetic behavior that was able to facilitate oxygen carrier recovery from the purge ash stream. In view of these results, the manganese-iron mixed oxide as oxygen carrier is proposed as a promising candidate for use coal combustion by the chemical looping process.
Biogas conversion is a renewable alternative for producing hydrogen. In this work, dry reforming of simulated biogas was performed in a 1 kWth continuous chemical looping reforming (CLR) unit in ...which the oxygen required for the partial oxidation of biogas to CO and H2 is supplied by an oxygen carrier. The performance of two different oxygen carriers (an iron oxide-based residue and a synthetic material based on an iron-manganese mixed oxide) was evaluated. The residue was capable of performing the dry reforming of biogas to a larger extent than the synthetic oxygen carrier. To enhance hydrogen yield, NiO addition was also considered with both materials. The presence of NiO increased methane conversion and H2 selectivity for both oxygen carriers. A value of approximately 2.6 mol H2/mol CH4 was achieved with both materials with the presence of only 2.7 wt% NiO in the bed.
•Dry-CLR of biogas was evaluated in a 0.5 kWth chemical looping unit.•Two Fe-based oxygen carriers tested: one residue and one iron-manganese mixed oxide.•The residue performed the dry reforming of biogas in a larger extent.•NiO addition to both oxygen carriers increased methane conversion and H2 selectivity.•Yield of 2.6 mol H2/molCH4 with both materials with 2.7 wt% NiO in the bed.
Highly N- and O-doped carbons were prepared from pine tannins by hydrothermal carbonisation (HTC) and subsequently applied as materials for supercapacitor electrodes. Pine tannins were transformed ...into carbon materials by using environment-friendly solvents (water or ammonia) without applying any activation or functionalisation post-treatment. Depending on the solution used for extracting tannins and on the HTC method, carbons with different physicochemical and electrochemical properties were obtained. The material prepared from the water-extracted tannin and subjected to HTC in ammonia displayed a porous texture composed of: (a) low ultramicroporosity and well-developed mesoporosity; (b) a hydrophilic surface with a high density of surface functionalities; and (c) a high nanotextural order. These features accounted for the excellent electrochemical performance of the resultant carbon electrode in terms of high rate capability up to 1 V s-1, high energy density up to similar to 1500 mA g-1, low cell resistance and fast frequency response, making it a suitable material for practical supercapacitors.
Chemical looping combustion (CLC) is a low-cost CO2 capture technology with a low energy penalty. Bio-energy with CO2 capture and storage (BECCS) opens up the possibility for negative CO2 emissions ...involving the removal of CO2 already emitted into the atmosphere. The oxygen needed for combustion in CLC processes is supplied by a solid oxygen carrier circulating between the fuel reactor and the air reactor. In this work, the combustion of different types of biomass, such as pine sawdust, olive stones and almond shells, was studied in a continuous 1.5kWth CLC unit. A mixed Cu-Mn oxide was used as the oxygen carrier. This material releases gaseous oxygen when reduced, resulting in Chemical looping combustion with oxygen uncoupling (CLOU). The released oxygen reacts with both the volatiles and char generated inside the fuel reactor when biomass is fed into it. The oxygen carrier is reoxidized in air inside the air reactor. High CO2 capture and 100% combustion efficiencies were achieved with this Cu-Mn oxygen carrier. The oxygen concentration inside the air reactor did not affect CO2 capture efficiency under the studied conditions.
•Combustion of three different biomasses was carried out in a CLOU unit.•Cu-Mn mixed oxide prepared by spray granulation was the oxygen carrier.•Complete combustion to CO2 and H2O was achieved in the interval 775–850°C.•CO2 capture efficiency depends on biomass type: pine>olive shell=almod shell.
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Biochar derived from the pyrolysis of pine tannin is a green and available by-product of oil manufacturing that presents interesting features after having been activated by KOH at ...650 °C. Different weight ratios of KOH to biochar were used and the resulting activated carbons (ACs) presented highly developed specific surface areas of up to 2190 m2 g−1, well-connected porosity and high oxygen content, leading to enhanced electrochemical performance when used as electrochemical capacitor electrodes in a 1 M H2SO4 aqueous electrolyte. Galvanostatic charge/discharge experiments evidenced that the best material achieved a maximum electrode capacitance of up to 232 F g−1 (at 0.5 A g−1) with a capacitance retention of 70% at 10 A g−1 using commercial mass loadings (i.e., approx. 10 mg cm−2). In addition, long cycling stability with a residual capacitance of 92 to 94% after 10,000 cycles at 5 A g−1 was achieved. These results prove that ACs derived from pine tannin biochars have great potential for their commercial use as electrochemical energy storage devices.
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