EtOH Concentrations Research Articles

Electrolyte Formulation By Design of Experiments: The Hidden Correlations in the Li-Mediated Nitrogen Reduction Reaction for Ammonia Production

Ammonia, a fundamental building-block for fertilizers and other many commodities, is responsible, through the Haber-Bosh (HB) process, of around 1.4% of the global greenhouse gas emissions. Indeed, HB operates in severe conditions (200 atm), and is fossil fuel dependent, since the few huge, centralized plants are combined with steam reforming for H2 production. To find a renewable-driven and delocalized electrochemical process for NH3 production, complementary to HB, could be a key solution for our society that is facing climate change crisis and that is demographically growing [1].In view of process electrification, the Li-mediated (Li-m) pathway represents the most promising solution in the N2 reduction reaction (NRR) challenging field. Exploiting the unique reducing power of this alkali metal, this strategy achieves the highest Faradic efficiency (FE) and NH3 production rate [2,3,4].Li+ ions from the aprotic electrolyte are electrodeposited on the cathode, where N2 is reduced and protonated into NH3 thanks to a proton donor or a proton shuttle, as EtOH. On the plated Li, a solid electrolyte interphase (SEI) unavoidably forms, and its nature and morphology are straightly dependent on the electrolyte composition. The different diffusion rate of Li+, N2, and H+ trough the SEI layer determines the selectivity towards NH3 formation. The correct reactant ratio at the electrode surface is essential to hinder both the hydrogen evolution reaction and an excessive Li plating, maximizing the FE [5,6].Design of experiment (DoE) together with response surface methodology (RSM) are a powerful tool that can reveal, with a restricted number of experiments (e.g. 9), the optimal composition of the electrolyte towards the highest FE and the hidden intercorrelations among variables. In particular, we aimed at studying two key variables, i.e. EtOH and Li-salt concentration; to this purpose, the Doehlert design with two factors and three replicates of the central point was chosen and RSM was employed to model the response and determine the optimal conditions.The study was repeated with two different fluorinated Li-salt, LiBF4 and LiFOB. LiBF4 has recently shown an improved stability and FE for the Li-m NRR process, correlated to the LiF presence in the SEI layer. The optimal combination of the electrolyte components obtained from the DoE for LiBF4 is in accordance with previous study, validating the statistical methodology applied. The newly proposed salt showed an increase of the 25% in the FE with respect to LiBF4 in the same conditions [7,8]. Experiments was conducted under 20 bar N2 in an autoclaved glass cell with a proper gas purification. As in previous study with this Li-m strategy in this set-up, even in this case the total NH3 amount obtained overcame the amount of possible impurities coming from the N2 gas, moreover controls tests with Ar instead of N2 were performed.

One-Pot Synthesis of 1,3,5-Trisubstitued Pyrazoles via Immobilized Thermomyces lanuginosus Lipase (TLL) on a Metal-Organic Framework.

A regioselective enzyme-catalyzed system is selected for the synthesis of 1,3,5-trisubstituted pyrazole derivatives by adding phenyl hydrazines, nitroolefins, and benzaldehydes. The reaction is performed in a one-pot vessel with a yield ranging from 49 to 90%. TLL@MMI, immobilized Thermomyces lanuginosus lipase (TLL) on a multivariate of MOF-5/IRMOF-3 (MMI), showed good performance for the catalysis of this reaction. The prepared biocatalyst was characterized by FTIR, XRD, SEM, and EDX. The thermal and solvent stability of TLL@MMI was investigated in MeOH and EtOH after 24 h incubation. In the presence of 100% concentrations of EtOH, TLL@MMI has 80% activity.

Reaction Mechanisms and Production of Hydrogen and Acetic Acid from Aqueous Ethanol Using a Rn-Sn/TiO2 Catalyst in a Continuous Flow Reactor

The catalytic reforming of bioethanol can produce green hydrogen (H2) and acetic acid (AcOH). In the present study, the conversion of aqueous ethanol (EtOH) over 4 wt%Ru-4 wt%Sn/TiO2 in a flow reactor was investigated at different temperatures at 0.1 MPa or at various pressures at 260 °C. The ethanol conversion was rather slow in liquid water, while the reactivity increased significantly when water was evaporated. Under gas-phase conditions at 0.1 MPa, the conversion rate increased with increasing reaction temperature, but the AcOH yield and H2 purity decreased due to by-production of CH4, CO, and CO2. The CH4 and CO generated by fragmentation of acetaldehyde (AA), an intermediate, were suppressed by increasing reaction pressure, although the formation of CH4 and CO2 generated from AcOH was pressure independent. Thus, the highest-pressure conditions in steam at a given reaction temperature are preferred for the production of pure H2. The initial step, EtOH → AA, was the rate-determining reaction, and the model experiments using AA as a substrate showed that the Cannizzaro reaction of two AA molecules to form EtOH and AcOH occurred preferentially. This oxidation system was confirmed to be effective at EtOH concentrations of up to 500 g/L in water.

Ultrasonication and RSM-based optimization of antioxidant activity, saccharide composition and fatty acids from Phoenix dactylifera L. Medjool date seeds influenced by ethanol

In response with the demand in date industry finding on sustainable solution for date seeds management and its bioactive rich constituent, current study envisaged the optimum condition for the ultrasound extraction of Phoenix dactylifera L. Medjool date seeds and its antioxidative activity by employing a three-level three-factor Box–Behnken design via response surface methodology (RSM). Ethanol (EtOH) concentration (50-80%), time (30-90 min) and temperature (40-70 °C) were the independent variables investigated for ABTS•+ scavenging antioxidant activity and subjected to analysis of variance (ANOVA). The optimum conditions for maximum antioxidant activity (60.93% ± 0.021) were achieved at 80% EtOH, 44 min and at 57 °C, where the effect of EtOH concentration were notably significant. The observed agreement between the experimental (60.93% ± 0.021) and predicted (60.35%) values indicated the employed model suitability while substantiates the successful implementation of RSM for optimizing extraction parameters. The optimized extract characterized through UPLC-QTOF/MS and GC-MS/MS, detailed the presence of saccharides (isomaltose, mannotriose and stachyose) and volatile compounds, namely 5 saturated fatty acids that encompassed within the 8.42% (w/w) of total fat obtained. This verifies the ability of the solvent mixture extracting fatty acids and saccharides even under high EtOH concentration.
 KEY WORDS: Date seeds, Response surface methodology (RSM), Antioxidant, Saccharide, GC-MS/MS, UPLC-QTOF/MS
 Bull. Chem. Soc. Ethiop. 2024, 38(3), 547-562. 
 DOI: https://dx.doi.org/10.4314/bcse.v38i3.1

Effects of Hovenia dulcis fruit and peduncle extract on alcohol metabolism

Ethnopharmacological relevanceThe dried fruit and peduncle of Hovenia dulcis Thunberg (Rhamnaceae) (HD) has been used as a folk medicine to treat liver disease, detoxify alcoholism, and prevent and cure hangovers. Aim of the studyWe investigated the pharmacology of HD on the kinetics of EtOH and on the enzymes related to alcohol metabolism to seek the scientific evidence of HD to prevent hangover, the effectiveness as a folk medicine. Materials and methodsEtOH was orally administered 30 min after oral administration of HD boiling water extract in rats. Then, the profiles of blood EtOH concentrations were measured. Mice were reared with food containing powdered HD for 7 days, and the activities of alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) in liver were measured. Hepa1c1c7 cells were cultured with the medium containing HD extract, and the activities of ADH and ALDH were measured. ResultsHD extract reduced the blood EtOH concentrations in rats and induced the activities of ADH and ALDH and mRNA and protein expressions of ADH1B, ALDH1A1, and ALDH2 in the liver of mice and Hepa1c1c7 cells. Dihydromyricetin, one of the ingredients of HD, significantly induced the activities of ADH and ALDH in Hepa1c1c7 cells, however, the fractions containing hydrophilic organic compounds with small molecular weight contributed the most of the activities of HD extract. ConclusionsWe clarified the experimental pharmacological evidences of HD as a folk medicine to detoxify alcoholism and prevent hangovers.

Dynamic Alterations to Hepatic MicroRNA-29a in Response to Long-Term High-Fat Diet and EtOH Feeding.

MicroRNA-29a (miR-29a) is a well characterized fibro-inflammatory molecule and its aberrant expression is linked to a variety of pathological liver conditions. The long-term effects of a high-fat diet (HFD) in combination with different levels of EtOH consumption on miR-29a expression and liver pathobiology are unknown. Mice at 8 weeks of age were divided into five groups (calorie-matched diet plus water (CMD) as a control group, HFD plus water (HFD) as a liver disease group, HFD plus 2% EtOH (HFD + 2% E), HFD + 10% E, and HFD + 20% E as intervention groups) and fed for 4, 13, 26, or 39 weeks. At each time point, analyses were performed for liver weight/body weight (BW) ratio, AST/ALT ratio, as well as liver histology assessments, which included inflammation, estimated fat deposition, lipid area, and fibrosis. Hepatic miR-29a was measured and correlations with phenotypic traits were determined. Four-week feeding produced no differences between the groups on all collected phenotypic traits or miR-29a expression, while significant effects were observed after 13 weeks, with EtOH concentration-specific induction of miR-29a. A turning point for most of the collected traits was apparent at 26 weeks, and miR-29a was significantly down-regulated with increasing liver injury. Overall, miR-29a up-regulation was associated with a lower liver/BW ratio, fat deposition, inflammation, and fibrosis, suggesting a protective role of miR-29a against liver disease progression. A HFD plus increasing concentrations of EtOH produces progressive adverse effects on the liver, with no evidence of beneficial effects of low-dose EtOH consumption. Moreover, miR-29a up-regulation is associated with less severe liver injury.

Exploring microstructure of MgCl2·nEtOH adducts for Ziegler-Natta catalysts

The activation of MgCl2 through the formation of MgCl2·nEtOH adducts is considered the principal step for the preparation of high performance Ziegler-Natta catalysts for olefins polymerizations in industry. Despite this importance, due to the complicated microstructure of the adducts, the precise structural characterization of these compounds has been left behind. In this research, four MgCl2.nEtOH adducts (with n = 0.6, 1.0, 1.8, and 3.2) were prepared by melt quenching procedure and assessed thoroughly by different techniques. Despite the multiple peaks in TGA analysis, similar FTIR spectra were recorded, and the adducts with n = 3.2 revealed sticky nature in SEM pictures which enhanced their particle size and broadened SPAN. According to the XRD spectra, the adducts showed distinct peaks related to the lateral cuts of distorted MgCl2, in which the ratio of α-MgCl2 to β-MgCl2 form enhanced by increasing the EtOH content, that was further confirmed by DFT calculations, even though it must be accepted that it is only a minimalist exercise in terms of a clear characterization of the adducts.

Effect of Ethanol Vapor Inhalation Treatment on Lethal Respiratory Viral Infection With Influenza A.

Ethanol (EtOH) effectively inactivates enveloped viruses in vitro, including influenza and severe acute respiratory syndrome coronavirus 2. Inhaled EtOH vapor may inhibit viral infection in mammalian respiratory tracts, but this has not yet been demonstrated. Here we report that unexpectedly low EtOH concentrations in solution, approximately 20% (vol/vol), rapidly inactivate influenza A virus (IAV) at mammalian body temperature and are not toxic to lung epithelial cells on apical exposure. Furthermore, brief exposure to 20% (vol/vol) EtOH decreases progeny virus production in IAV-infected cells. Using an EtOH vapor exposure system that is expected to expose murine respiratory tracts to 20% (vol/vol) EtOH solution by gas-liquid equilibrium, we demonstrate that brief EtOH vapor inhalation twice a day protects mice from lethal IAV respiratory infection by reducing viruses in the lungs without harmful side effects. Our data suggest that EtOH vapor inhalation may provide a versatile therapy against various respiratory viral infectious diseases.

Sex chromosome and gonadal hormone contributions to binge-like and aversion-resistant ethanol drinking behaviors in Four Core Genotypes mice.

While substantial research has focused on the contribution of sex hormones to driving elevated levels of alcohol drinking in female rodents, fewer studies have investigated how genetic influences may underlie sex differences in this behavior. We used the Four Core Genotypes (FCG) mouse model to explore the contribution of sex chromosome complement (XX/XY) and gonad type [ovaries (Sry-)/testes (Sry+)] to ethanol (EtOH) consumption and quinine-resistant drinking across two voluntary self-administration tasks: limited access consumption in the home cage and an operant response task. For limited access drinking in the dark, XY/Sry + (vs. XX/Sry +) mice consumed more 15% EtOH across sessions while preference for 15% EtOH vs. water was higher in XY vs. XX mice regardless of gonad type. XY chromosomes promoted quinine-resistant drinking in mice with ovaries (Sry-) and the estrous cycle did not affect the results. In the operant response task, responding for EtOH was concentration dependent in all genotypes except XX/Sry + mice, which maintained consistent response levels across all concentrations (5-20%) of EtOH. When increasing concentrations of quinine (100-500 μM) were added to the solution, FCG mice were insensitive to quinine-punished EtOH responding, regardless of sex chromosome complement. Sry + mice were further found to be insensitive to quinine when presented in water. Importantly, these effects were not influenced by sensitivity to EtOH's sedative effect, as no differences were observed in the time to lose the righting reflex or the time to regain the righting reflex between genotypes. Additionally, no differences in EtOH concentration in the blood were observed between any of the genotypes once the righting reflex was regained. These results provide evidence that sex chromosome complement regulates EtOH consumption, preference, and aversion resistance and add to a growing body of literature suggesting that chromosomal sex may be an important contributor to alcohol drinking behaviors. Examination of sex-specific genetic differences may uncover promising new therapeutic targets for high-risk drinking.

Ethanol combined with energy drinks: Two decades of research in rodents

Many studies raised concerns on alcoholic beverages consumption mixed with energy drinks (AmED), which can induce higher rates of binge drinking and earlier development of alcohol use disorders. After 20 years of research, few studies with laboratory animals have focused on the effects of this mixture and the neurobiological and pharmacological mechanisms underlying them. We found 16 articles on AmED administration to rodents evaluating its effects on voluntary consumption, locomotion, anxiety-like behavior, memory, influence on the onset time of seizures, biochemical and neurochemical measures. Some of these studies indicated energy drinks (ED) can alter the pattern of use and motivation to consume ethanol (EtOH); increase the expression of sensitization to EtOH stimulant effect and the proportion of sensitized mice; decrease the aversiveness of high concentrations of EtOH, among other effects. In addition AmED hastens the loss of righting reflex and its effects on memory are controversial. After acute administration no difference was found in blood ethanol concentration (BEC) of rodents which received EtOH with or without ED, but after 60 days of treatment, AmED group had lower BEC levels than EtOH group. Data on biochemical and neurochemical parameters after AmED are not consistent. Although the AmED group presented higher glucose levels than the EtOH group when drugs were administered by gavage, this was not observed in a self-administration protocol. AmED may induce higher kidney damage, higher levels of plasma urea, uric acid and creatinine when compared to EtOH. Chronic consumption of AmED causes an inflammatory response and oxidative stress, which may induce cell death in the cortex and hypothalamus of adult rats. These controversial results show that AmED diverse effects depend on sex, age and lineage of the animals, duration of the treatment and route of administration. Further research is necessary to evaluate the mechanisms underlying AmED biological effects.

Revisiting the Solubility–Permeability Relationship with Hydrophobic Drug Umifenovir in Pluronic Solutions: Impact of pH and Co-Solvent

This study describes the influence of pluronic F-127 (F-127) and ethanol (EtOH) on the solubility of umifenovir (UMF) in buffer solutions of pH 2.0 and pH 7.4, and its permeability through cellulose membranes. A 44.4-fold greater UMF solubility in acidic medium as compared to an alkaline one was estimated at 310.15 K. The concentration of UMF in the saturated solution was enhanced by the interaction with F-127 micelles. The combined positive effect of EtOH and F-127 on the solubility was estimated. The aggregation number of F-127 micelles in the presence of 10% and 20% ethanol appeared to be reduced by 2.1-fold and 4.1-fold, respectively, as compared to buffer pH 7.4. The presence of ethanol in buffer pH 7.4 solution provided better solvent conditions but inhibited the formation of F-127 micelles. The impact of UMF on the aggregation number of F-127 was not pronounced and was expressed only by a slight increase of 1 and 3 units in 10% and 20% EtOH, respectively. According to the values of zeta potential, addition of EtOH reduced the stability of the system. The permeation of UMF in buffer pH 7.4 measured through the cellulose membrane MWCO 12-14 kDa was increased 1.4-fold by 10% EtOH. An increase in EtOH content to 20% reduced this effect to 1.2-fold. Decreasing effect of 1.5% F-127 on the permeability was inhibited by using 10% EtOH. The solution containing 1.5% F-127 and 10% EtOH was shown to be an advantageous system for UMF in view of the solubility-permeability balance. The authors suppose the findings of the study to be useful for the design of pharmaceutical formulations based on UMF antiviral drugs.

Promotion and mechanism of action of EtOH addition on the energy release characteristics of B/JP-10 suspension fuel

B/JP-10 suspension fuel is a novel energetic blended fuel with high application prospects, but it suffers from incomplete energy release in the actual combustion process. In this study, B/EtOH/JP-10 suspension fuels with different EtOH contents were prepared by a two-step method. The ignition and combustion characteristics were investigated using a CO2 laser ignition test system. The focus is on the effect of EtOH addition on the fragmentation process and energy release of boron agglomerates. The results show that the addition of EtOH changes the ignition pattern of B/JP-10 suspension fuel and thus shortens its ignition delay, and the ignition delay of fuel droplets decreases with increasing EtOH content when the EtOH content is >31.2 wt%. During the combustion process, on the one hand, EtOH will strengthen the droplet's own “microburst” in the early stage of combustion, transporting JP-10 vapor and active boron to the oxygen-rich zone, thus improving the utilization of oxygen around the droplet; on the other hand, after the agglomerates are formed, EtOH will gradually break the agglomerates and transport active boron outward, promoting the contact between active boron and oxygen and finally improving the overall energy release efficiency of the fuel.

Beam-induced redox chemistry in iron oxide nanoparticle dispersions at ESRF-EBS.

The storage ring upgrade of the European Synchrotron Radiation Facility makes ESRF-EBS the most brilliant high-energy fourth-generation light source, enabling in situ studies with unprecedented time resolution. While radiation damage is commonly associated with degradation of organic matter such as ionic liquids or polymers in the synchrotron beam, this study clearly shows that highly brilliant X-ray beams readily induce structural changes and beam damage in inorganic matter, too. Here, the reduction of Fe3+ to Fe2+ in iron oxide nanoparticles by radicals in the brilliant ESRF-EBS beam, not observed before the upgrade, is reported. Radicals are created due to radiolysis of an EtOH-H2O mixture with low EtOH concentration (∼6 vol%). In light of extended irradiation times during insitu experiments in, for example, battery and catalysis research, beam-induced redox chemistry needs to be understood for proper interpretation of insitu data.

Influence of Two Widely Used Solvents, Ethanol and Dimethyl Sulfoxide, on Human Sperm Parameters.

To study mechanisms involved in fertility, many experimental assays are conducted by incubating spermatozoa in the presence of molecules dissolved in solvents such as ethanol (EtOH) or dimethyl sulfoxide (DMSO). Although a vehicle control group is usually included in such studies, it does not allow to evaluate the intrinsic effect of the solvent on sperm parameters and its potential influence on the outcome of the experiment. In the present study, we incubated human spermatozoa for 4 h in a capacitation medium in the absence or the presence of different concentrations of EtOH and DMSO (0.1, 0.5, 1.0, and 2.0%) to assess the impact of these solvents on sperm motility, vitality, capacitation, and acrosome integrity. The presence of statistically significant relationships between increasing solvent concentrations and the investigated parameters was assessed using linear mixed models. A significant effect was observed with both solvents for total and progressive sperm motilities. We also evaluated the effect of time for these parameters and showed that the influence of the solvents was stable between 0 and 4 h, indicating an almost direct impact of the solvents. While EtOH did not influence sperm vitality and acrosome integrity, a significant effect of increasing DMSO concentrations was observed for these parameters. Finally, regarding capacitation, measured via phosphotyrosine content, although a dose-dependent effect was observed with both solvents, the statistical analysis did not allow to precisely evaluate the intensity of the effect. Based on the results obtained in the present study, and the corresponding linear mixed models, we calculated the concentration of both solvents which would result in a 5% decline in sperm parameters. For EtOH, these concentrations are 0.9, 0.7, and 0.3% for total motility, progressive motility, and capacitation, respectively, while for DMSO they are 1.5, 1.1, >2, 0.3 and >2% for total motility, progressive motility, vitality, capacitation, and acrosome integrity, respectively. We recommend using solvent concentrations below these values to dissolve molecules used to study sperm function in vitro, to limit side effects.

Optimization of Major Extraction Variables to Improve Recovery of Anthocyanins from Elderberry by Response Surface Methodology

Elderberry, which is well known for its richness in anthocyanin, is attracting attention in the bioindustry as a functional material with high antioxidant capacity. The aim of this study is to optimize extraction conditions to more effectively recover anthocyanins from elderberry. In a fundamental experiment to determine the suitable solvent, various GRAS reagents, such as acetone, ethanol, ethyl acetate, hexane, and isopropyl alcohol, were used, and total phenol and anthocyanin contents were detected as 9.0 mg/g-biomass and 5.1 mg/g-biomass, respectively, only in the extraction using ethanol. Therefore, ethanol was selected as the extraction solvent, and an experimental design was performed to derive a response surface model with temperature, time, and EtOH concentration as the main variables. The optimal conditions for maximal anthocyanin recovery were determined to be 20.0 °C, 15.0 min, and 40.9% ethanol, and the total anthocyanin content was 21.0 mg/g-biomass. In addition, the total phenol and flavonoid contents were detected as 67.4 mg/g-biomass and 43.8 mg/g-biomass, respectively. The very simple and economical extraction conditions suggested in this study contributed to improving the utilization potential of anthocyanin, a useful antioxidant derived from elderberry.

Morphological, physicochemical, techno-functional, phytochemical, and antioxidant evaluation of polyembryonic and non-polyembryonic maize sprouts

The growing demand for foods with better characteristics has led to the search for new alternatives, one of these being sprouts, of which polyembryonic maize kernels have been little studied. The objective of this work was to evaluate the morphological changes, as well as the physicochemical, techno-functional, phytochemical, and antioxidant properties of polyembryonic (Pem) and non-polyembryonic (NPem) corn sprouts at different germination times (0, 5, 10, and 15 days). Different analytical techniques as well as “green” extraction technique (Microwave-ultrasound) with various solvents were used to obtain phytochemicals. PEm “normal high polyembryony” (NAP) and NPEm “landrace” (CRO) maize showed higher growth (up to 24.7 and 30.6 cm) and moisture content (up to 89.5 and 87.7%). Overall protein content increased by up to 51% relative to the initial value, with higher PEm content (15.0 and 14.5% in “brachytic high polyembryony” (BAP) and NAP maize respectively). Fibre and protein content were negatively correlated with starch content. Likewise, the techno-functional properties improved, with higher values for NAP, BAP and CRO at 10 and 15 days of germination. PEm presented higher yields (13 times higher), higher content of hydrolysable polyphenols (553.08 ± 44.68 mg/100 g (BAP)) at 1/16 concentrations of 70% EtOH, and higher content of condensed tannins (1623.38 mg/100 g (NAP)) at 1/8 and 30% EtOH concentrations. Finally, PEm showed higher antioxidant activity which can be attributed to the content and presence of different polyphenols. The results indicate that sprouts produced from polyembryonic maize kernels present better physicochemical, phytochemical, techno-functional and antioxidant properties.

Development of periodic colored bands via frontal polymerization

The development of periodic brown-white colored structural patterns during the frontal polymerization process has been studied in Methacrylic acid (MAA), Resorcinol, Benzoyl peroxide (BP), and N, N Dimethyl aniline (DMA) reaction system. The reaction has been carried out in a thin glass test tube under ambient conditions. Pattern formation and their dependency on the concentration of MAA monomer, Resorcinol, and DMA initiator have largely been observed. Methanol has also been used as a solvent to optimize the effect of dilution levels on the periodicity of colored structural patterns. The materials characterization is carried out using NMR, SEM, IR, CHNS, and UV–visible analyses to show the possible reaction mechanisms and elemental composition of the polymerization reaction. It has been observed that white and brown colored polymeric phases are formed during FP reactions and polymerized simultaneously. In this context, a possible chemical mechanism has been proposed which shows the formation of white colored polymethacrylic acid and brown phase poly (2–hydroxy, 1, 4 napthaquinone methacrylic acid). The analytical data observed during the study has a good agreement with the proposed chemical mechanism. The characteristics of colored patterns found depending on the concentration of resorcinol, BP, and EtOH have been studied and properly discussed.

A pilot investigation of the efficacy and safety of magnesium chloride and ethanol as anesthetics in Loligo vulgaris embryos.

The inclusion of cephalopods in the legislation related to the use of animals for experimental purposes has been based on the precautionary principle that these animals have the capacity to experience pain, suffering, distress, and lasting harm. Recent studies have expanded this view and supported it. Handling cephalopod mollusks in research is challenging and whenever more invasive procedures are required, sedation and/or anesthesia becomes necessary. Therefore, finding adequate, safe, and effective anesthetics appears mandatory. Several substances have been considered in sedating cephalopods, in some instances applying those utilized for fish. However, species-specific variability requires more detailed studies. Despite long-lasting experience being linked to classic studies on squid giant axons, evidence of action on putative anesthetic substances is scarce for Loligo vulgaris and particularly for their embryos. The aim of the current study was to evaluate effects elicited by immersion of squid embryos in anesthetic solutions and examine whether these forms display a similar reaction to anesthetics as adults do. Different concentrations of ethanol (EtOH; 2, 2.5, and 3%) and magnesium chloride (MgCl2; 1, 1.5, and 1.8%) were tested by adopting a set of indicators aimed at exploring the physiological responses of squid embryos. Forty-two embryos of the common squid Loligo vulgaris (stages 27-28) were assigned to three conditions (EtOH, MgCl2, and controls) and video recorded for 15min (5min before, 5min during, and 5min after immersion in the anesthetic solutions). In each group, the heart rate, respiratory rate, buoyancy, chromatophore activity, and tentacles/arms responses were assessed to evaluate the embryos' vitality and responsiveness to stimulation. Both substances provoked a decrease in heart and respiratory rates and inhibited buoyancy, chromatophores, and tentacles/arms responses; no adverse effects were observed. EtOH had a faster onset of action and faster recovery than MgCl2, being potentially more adequate as an anesthetic for shorter procedures. Even though MgCl2 caused a longer muscle relaxation, the reversibility was not confirmed for the 1.8% concentration; however, lower concentrations triggered similar results as the ones obtained with the highest EtOH concentrations. We have shown that the late developmental stages of Loligo vulgaris embryos could represent a good model to evaluate anesthetics for cephalopods since they can display similar reactions to anesthetics as adults animals do.

Thermodynamic parameters and quantum chemical calculations of complex formation between rutin and 2-hydroxypropyl-β-cyclodextrin in water-ethanol solvents

The thermodynamic parameters of the complexation between rutin (Rut) and hydroxypropyl-β-cyclodextrin (HP-β-CD) in water–ethanol solvents (lgK, ΔrH, ΔrG, TΔrS) were calculated from isothermal titration calorimetry. A decrease in the stability of the complex was observed with an increase in EtOH concentration in the solvent, and the change in the Gibbs energy of the complex formation is controlled by the enthalpy factor. The increase of the entropy contribution to the change in the Gibbs energy of the [Rut ⊂ HP-β-CD] complex formation reaction is probably caused by an increase in the number of free water molecules as a result of the Rut and HP-β-CD desolvation in aqueous-ethanol solvents. The effect of different solvents such as water and ethanol was included via the analytical linearized Poisson-Boltzmann (ALPB) model, which was implemented in the GFN2-xTB code. The effect of solvent on the rutin’s ability to interact with HP-β-CD is decreasing in the following order: water > ethanol.

Diagnostic meaning of urinary ethyl glucoside concentrations in relationship to alcoholic beverage consumption

Incidents and accidents often involve the drinking of alcoholic beverages. We investigated compounds that indicate the consumption of alcoholic beverages even after ethanol (EtOH) becomes undetectable in blood and urine. Ethyl glucoside (EG) has been isolated as a possible drinking marker, and a GC–MS/MS method for EG isomers has been developed. EG isomers in several alcoholic beverages were analyzed. In sake, only αEG was observed in high concentrations. In wine and beer, both α and βEG were detected. Whisky, however, did not contain EG. EtOH and EG concentrations were analyzed in urine up to 48 h after ingestion. Maximum EtOH concentrations were reached in 1–2 h and was mostly eliminated in 6 h. Maximum EG concentrations were reached in 3–6 h, gradually decreased, and remained low after 24 h. After drinking sake, the αEG concentrations were much higher than that of other alcoholic beverages. After drinking wine or beer, βEG was detected, but lower than αEG. Also, αEG was detected in urine after drinking whisky that contained no EG. This suggested that αEG may be synthesized in vivo. Disaccharide-degrading enzymes such as α-glucosidase are present in the human small intestine. It was considered that αEG was synthesized when alcohol was consumed with certain foods, such as carbohydrates. In actual forensic autopsy cases, EtOH and EG isomer analysis provided useful information regarding drinking history. In conclusion, it is considered that urinary EG isomers can be used as drinking markers that complement EtOH analysis.