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Multi-dimensional quantum mechanical simulations are carried out to understand the multi-state and multi-mode vibronic interactions in the first six low-lying viz., X ̃ 2 B 1 , A ̃ 2 A 1 , B ̃ 2 B 2 , C ̃ 2 A 2 , D ̃ 2 A 1 , and E ̃ 2 B 1 electronic states of c-C2H4O·+. Vibronic coupling theory is applied to study interactions among electronic states using symmetry selection rules. A model 6 × 6 diabatic electronic Hamiltonian is constructed. The parameters of the diabatic Hamiltonian are estimated by performing extensive ab initio electronic structure calculations, using the EOM-IP-CCSD method. The nuclear dynamics calculations are performed with both time-independent and time-dependent quantum mechanical methods. The calculated vibronic structures of six electronic states are found to be in excellent agreement with the available experimental findings. Progressions found in the theoretical spectrum are assigned in terms of vibrational modes. It is found that extremely strong vibronic interactions among the X ̃ 2 B 1 – A ̃ 2 A 1 , B ̃ 2 B 2 – C ̃ 2 A 2 , and D ̃ 2 A 1 – E ̃ 2 B 1 electronic states results into highly overlapping vibronic bands due to multiple multi-state conical intersections. The impact of associated nonadiabatic effects on the vibronic structure and dynamics of the mentioned electronic states is examined at length. Interesting comparison is made with the results obtained for the isomeric acetaldehyde radical cation. [ABSTRACT FROM AUTHOR]

We investigate roaming in the photodissociation of acetaldehyde (CH3CHO), providing insights into the contrasting roaming dynamics observed for this molecule compared to formaldehyde. We carry out trajectory studies for full-dimensional acetaldehyde, supplemented with an analysis of a two-degree-of-freedom restricted model and obtain evidence for two distinct roaming pathways. Trajectories exhibit roaming at both shorter (9–11.5 au) and larger (14.5–22.9 au) maximum CH3–HCO separations, characterized by differing amounts of HCO rotation. No roaming trajectories were found in the intervening gap region. The roaming dynamics near 14.5–22.9 au are well-reproduced by the restricted model and involve passage through a centrifugal barrier, analogous to formaldehyde roaming. However, the shorter-range 9–11.5 au roaming appears unique to acetaldehyde and is likely facilitated by repulsive interactions absent in the simplified models. Phase space analysis reveals that this additional roaming pathway is inaccessible in the reduced dimensionality system. The findings suggest that acetaldehyde's increased propensity for roaming compared to formaldehyde may arise from the presence of multiple distinct roaming mechanisms rather than solely the higher roaming fragment mass. [ABSTRACT FROM AUTHOR]

Acetaldehyde is a very relevant atmospheric species whose photodissociation has been extensively studied in the first absorption band both experimentally and theoretically. Very few works have been reported on acetaldehyde photodissociation at higher excitation energies. In this work, the photodissociation dynamics of acetaldehyde is investigated by means of high-level multireference configuration interaction ab initio calculations. Five different fragmentation pathways of acetaldehyde are explored by calculating the potential-energy curves of the ground and several excited electronic states along the corresponding dissociating bond distances. The excitation energy range covered in the study is up to 10 eV, nearly the ionization energy of acetaldehyde. We intend to rationalize the available experimental results and, in particular, to elucidate why some of the studied fragmentation pathways are experimentally observed in the different excitation energy regions and some others are not. Based on the shape of the calculated potential curves, we are able to explain the main findings of the available experiments, also suggesting possible dynamical dissociation mechanisms in the different energy regions. Thus, the reported potential curves are envisioned as a useful tool to interpret the currently available experiments as well as future ones on acetaldehyde photodissociation at excitation wavelengths in the range studied here. [ABSTRACT FROM AUTHOR]

A new portable miniaturized atmospheric microplasma discharge (μAPD) system coupled with the optical emission spectrometry (OES) detection for the determination of Hg in water samples was developed. The device was built from cheap, easily replaceable, and commercially available parts and was able to work with the photo-induced chemical vapor generation (PCVG). To optimize the photochemical volatile Hg generation process, a wide range of low molecular weight organic compounds (LMWOCs), namely formic, oxalic, acetic, propionic, and malonic acids, in addition to methanol, ethanol, glycerin, ethylene glycol, formaldehyde, and acetaldehyde, were tested to establish their influence on the signal of Hg. To assess the excitation and atomization potential of the newly developed μAPD system and its impact on the analytical performance of this microplasma excitation source, the plasma temperatures and the electron number density were evaluated. The analytical figures of merit were determined for the coupled PCVG-μAPD system. Additionally, the usability of the method was tested in reference to the analysis of selected environmental samples, i.e., tap, well, and river water spiked with Hg. A recovery test was also performed to evaluate the accuracy of the method. The examined analytical system allowed to detect Hg in water at a level lower than 0.33 μg L−1 when operating it at relatively low sample flow rates (2 mL min−1) and Ar supporting and plasma forming gas rates (20 mL min−1). The precision of measurements was better than 5% for formic acid. We believe that the presented system might be an attractive, cheaper alternative to commercial, highly expensive systems, e.g. based on inductively coupled plasma optical emission spectrometry (ICP OES). [ABSTRACT FROM AUTHOR]

The effects of the simultaneous consumption of amphetamine or amphetamine derivatives and alcohol have not yet been adequately clarified, particularly concerning potential condensation products resulting from the endogenous reaction between these substances and their metabolites (e.g., acetaldehyde, a metabolite of ethanol). In this study, we developed an LC–MS/MS method employing liquid–liquid extraction for the qualitative detection of some relevant condensation products belonging to the class of tetrahydroisoquinolines and their derivatives in human blood, brain, and liver samples. This includes the analysis of the substrates amphetamine, methamphetamine, methylenedioxymethamphetamine, methylenedioxyamphetamine, as well as the condensation products 1,3-dimethyl-1,2,3,4-tetrahydroisoquinoline, N-methyl-1,3-dimethyl-1,2,3,4-tetrahydroisoquinoline, 1,3-dimethyl-7,8-methylenedioxy-1,2,3,4-tetrahydroisoquinoline, and N-methyl-1,3-dimethyl-7,8-methylenedioxy-1,2,3,4-tetrahydroisoquinoline. Therefore, the reference standards of the mentioned tetrahydroisoquinolines were synthesized in advance and the method was validated with regard to the question of the qualitative detection of these compounds. The validation parameters included selectivity, specificity, limit of detection, lower limit of quantification, recovery, matrix effects, and stability for blood, brain, and liver samples. Following the analysis of human blood and post-mortem tissue samples, evidence of the condensation product 1,3-dimethyl-1,2,3,4-tetrahydroisoquinoline originating from the interaction between amphetamine and acetaldehyde was identified in two liver samples. On the contrary, no evidence of this or other tetrahydroisoquinolines was found in the remaining tissue and serum samples. [ABSTRACT FROM AUTHOR]

We report the catalytic synthesis of 3‐hydroxy‐2‐butanon (acetoin) from acetaldehyde as a key step in the synthesis of C4‐molecules from ethanol. Facile C−C bond formation at the α‐carbon of the C2 building block is achieved using an N‐heterocyclic carbene (NHC) catalyst. The immobilization of the catalyst on a Merrifield's peptide resin and its spectroscopic characterisation using solid‐state Nuclear Magnetic Resonance (NMR) is described herein. The immobilization of the NHC catalyst allows for process intensification steps and the reported catalytic system was subjected to batch recycling as well as continuous flow experiments. The robustness of the catalytic system was shown over a maximum of 10 h time‐on‐stream. Overall, high selectivity S>90 % was observed. The observed deactivation of the catalyst with increasing time‐on‐stream is explained by ex‐situ1H solution‐state, as well as 13C and 15N solid‐state NMR spectra allowing us to develop a deeper understanding of the underlying decomposition mechanism of the catalyst. [ABSTRACT FROM AUTHOR]

Photo‐driven cross‐coupling of o‐arylenediamines and alcohols has emerged as an alternative for the synthesis of bio‐active benzimidazoles. However, tackling the key problem related to efficient adsorption and activation of both coupling partners over photocatalysts towards activity enhancement remains a challenge. Here, we demonstrate an efficient interface synergy strategy by coupling exposed oxygen vacancies (VO) and Pd Lewis acid sites for benzimidazole and hydrogen (H2) coproduction over Pd‐loaded TiO2 nanospheres with the highest photoredox activity compared to previous works so far. The results show that the introduction of VO optimizes the energy band structure and supplies coordinatively unsaturated sites for adsorbing and activating ethanol molecules, affording acetaldehyde active intermediates. Pd acts as a Lewis acid site, enhancing the adsorption of alkaline amine molecules via Lewis acid‐base pair interactions and driving the condensation process. Furthermore, VO and Pd synergistically promote interfacial charge transfer and separation. This work offers new insightful guidance for the rational design of semiconductor‐based photocatalysts with interface synergy at the molecular level towards the high‐performance coproduction of renewable fuels and value‐added feedstocks. [ABSTRACT FROM AUTHOR]

Acetaldehyde is a key carbonyl by-product during red wine alcoholic fermentation; it is reactive and takes part in certain reactions involving anthocyanin. The aim of this study was to investigate the influence of SO2 and condensed tannin on the acetaldehyde accumulation of Saccharomyces cerevisiae (S. cerevisiae) during alcoholic fermentation and the ripple effect on wine anthocyanin. In this study, six sets of Cabernet Sauvignon alcoholic fermentation with two different sulfur levels (HS and LS) were carried out by adding exogenous condensed tannins before fermentation (T0) in the acetaldehyde rise period (TA) of S. cerevisiae and at the end of fermentation (TE), separately. The acetaldehyde evolution was identified during fermentation and anthocyanin was analyzed comparatively. The results showed that HS treatment slowed down the degradation of acetaldehyde, while tannins accelerated the degradation of acetaldehyde during alcoholic fermentation, especially TA wines. Furthermore, TA wines possessed a unique anthocyanin profile after fermentation regardless of SO2 level compared with other wines. These results suggest that acetaldehyde-mediated anthocyanin polymerization most likely occurs timely at the acetaldehyde production phase of S. cerevisiae during alcoholic fermentation, and managing tannin addition time during production could be used to regulate the anthocyanin profile. [ABSTRACT FROM AUTHOR]

We have addressed critical challenges in probiotic design to develop a commercially viable bacterial strain capable of removing the intestinal toxin, acetaldehyde. In this study, we report the engineering of the hag locus, a σD-dependent flagellin expression site, as a stable location for robust enzyme production. We demonstrate constitutive gene expression in relevant conditions driven by the endogenous hag promoter, following a deletion of the gene encoding a post-translational regulator of σD, FlgM, and a point mutation to abrogate the binding of the translational inhibitor CsrA. Reporter constructs demonstrate activity at the hag locus after germination, with a steady increase in heterologous expression throughout outgrowth and vegetative growth. To evaluate the chassis as a spore-based probiotic solution, we identified the physiologically relevant ethanol metabolic pathway and the subsequent accumulation of gut-derived acetaldehyde following alcohol consumption. We integrated a Cupriavidus necator aldehyde dehydrogenase gene (acoD) into the hag locus under the control of the flagellin promoter and observed a rapid reduction in acetaldehyde levels in gut-simulated conditions post-germination. This work demonstrates a promising approach for the development of genetically engineered spore-based probiotics. [ABSTRACT FROM AUTHOR]

The photocatalytic conversion of ethanol and the simultaneous development of hydrogen technology play a role in solving the energy crisis and reducing environmental pollution. In this research, rod-like M-MoS2 serves as a channel for charge transfer, leading to superior photocatalytic activity compared to H-MoS2. Further, two-dimensional (2D) B-doped C3N4 (BCN) nanosheets were anchored on the one-dimensional (1D) rod-like M-MoS2 surface to form a 1D/2D heterojunction, with M-MoS2/BCN-0.08 (mass ratio of M-MoS2:BCN of 0.08:1) exhibiting the highest photocatalytic performance. Under visible light irradiation, the ethanol conversion rate reached 1.79% after 5 h of photocatalytic reaction per gram of catalyst, while generating 421 μmol of 2,3-butanediol (2,3-BDO), 5460 μmol of acetaldehyde (AA), and 5410 μmol of hydrogen gas (H2). This different characterization provides evidence that a significant amount of photoinduced electrons generated in BCN under illumination conditions rapidly transfer to the conduction band (CB) of M-MoS2 through the rod-like structure of M-MoS2, and finally transfer to Pt to promote the production of hydrogen gas. The photoinduced holes in the valence band (VB) of M-MoS2 are rapidly consumed by ethanol upon transferring to BCN, effectively separating the photoinduced electron–hole pairs and resulting in superior photocatalytic performance. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is the synthesis and characterization of a CMYK palette (cyan of Cr-BiVO4, magenta of Pr-CeO2, yellow of Bi-(Ce,Zr)O2 composite and black of YMnO3) as an eco-friendly polyfunctional palette that combines (a) high near-infrared reflectance (cool pigments) that allows moderate temperatures in indoor environments and the urban heat island effect; (b) photocatalytic activity for the degradation of organic contaminants of emerging concern of substrates in solution (such as Orange II or methylene blue) and gaseous (NOx and volatile organic compounds such as acetaldehyde or toluene); (c) X-ray radiation attenuators associated with bismuth ions; and (d) biocidal effect combined with co-doping with bactericidal agents. Design/methodology/approach: Pigments were prepared by a solid-state reaction and characterized by X-ray diffraction, diffuse reflectance spectroscopy, photocatalytic activity over Orange II and scanning electron microscopy. Findings: The behaviour of the proposed palette was compared to that of a commercial inkjet palette, and an improvement in all functionalities was observed. Social implications: The functionalities of pigments allow the building envelope and indoor walls to exhibit temperature-moderating effects (with the additional effects of moderating global warming and increasing air conditioning efficiency), purification and disinfection of both indoor and outdoor air, and radiation attenuation. Originality/value: The proposed palette and its polyfunctional characterization are novel. [ABSTRACT FROM AUTHOR]

Practical Application Unlike many commercial sweeteners for which sweetness dose‐response curves have been constructed, honey's sweetness has yet to be quantified. Honey differs from most commercial sweeteners in that it has a robust aroma; this aroma may impact its perceived sweetness. This study quantified the sweetness intensity and the impact of aroma on the perceived sweetness of four different honey varieties (clover, wildflower, alfalfa, and orange) compared to sucrose. Each sweetener evaluated was diluted to six concentrations in water ranging from 12.5 g/L to 125 g/L. Panelists (n = 55) rated the sweetness intensities with and without aroma, in replicate, on the Global Sensory Intensity Scale. Additionally, the volatile organic compounds in the honey samples were profiled using gas chromatography‐mass spectrometry (GC/MS) analysis. Honey and sugar were equivalently sweet at a given concentration (g/L), with aroma present (p = 0.251). Additionally, honey and sugar were not equivalently sweet without aroma; aroma significantly increased sweetness intensities for all sweeteners (p = 0.042) and especially honeys. In a 100 g/L solution, the aromas in honey increased its sweetness by 23%–43%, depending on the floral source. Compounds with sweet aroma characteristics were identified at high concentrations in all honey samples using GC/MS analysis, including furfural, benzaldehyde, benzene acetaldehyde, and dimethyl sulfide. Additionally, (S)‐limonene and toluene were present in high quantities in the orange and alfalfa samples. This study can inform appropriate honey usage levels and identify major volatiles that may enhance sweetness.Honey sweetness has not been determined quantitatively, despite the widespread use of honey among consumers and product formulators. Sweetness enhancement by honey aroma volatiles may support a reduction in added sugars while maintaining sweetness intensity. [ABSTRACT FROM AUTHOR]

Alcohol-related hangovers impact both physical and mental wellness, largely due to acetaldehyde levels produced through alcohol metabolism. The present study investigated the efficacy and safety of the Wilac L probiotic complex (Levilactobacillus brevis WiKim0168 and Leuconostoc mesenteroides WiKim0172 isolated from kimchi) in improving hangovers post-alcohol consumption. This study was conducted as a randomized, double-blind, crossover placebo-controlled clinical trial from August 2023 to February 2024. Subjects (n = 26) were randomized into six test groups consuming three products, the Wilac L probiotic complex, Wilac L35 (Wilac L probiotic complex with Pyrus pyrifolia Nakai), or placebo, in different orders with crossover after a wash-out interval of 7–10 days. Blood alcohol and acetaldehyde concentrations were measured 0, 0.25, 0.5, 1, 2, 4, 6, and 15 h after alcohol consumption. The blood acetaldehyde levels measured with Wilac L probiotic complex supplementation were significantly lower than the control at 0.25 (p = 0.0381), 0.5 (p = 0.0498), and 1 h (p = 0.0260) post-consumption. The blood acetaldehyde levels after Wilac L35 consumption compared to the control are significant at 0.25 (p = 0.0115), 0.5 (p = 0.0054), 1 (p = 0.0285), 2 (p = 0.0113), and 6 h (p = 0.0287) post-consumption. No significant adverse events were reported. The Wilac L probiotic complex is associated with decreased blood acetaldehyde levels and improved subjective hangover symptoms. [ABSTRACT FROM AUTHOR]

The conversion of methanol over zeolites offers a sustainable alternative for fuels and chemicals production. However, a complete understanding of the competing reaction pathways, particularly those leading to C-C bond formation, remains elusive. This work presents a novel mechanism for selective methanol conversion in ZSM-5 zeolites, involving a Brønsted acid site (BAS)-mediated Meerwein–Ponndorf–Verley (MPV) reduction pathway. Employing a multidimensional solid-state NMR spectroscopy combined with isotopic labeling and theoretical calculations, we identify this pathway for acetaldehyde reduction with methanol, directly contributing to ethene formation. This mechanism, involving carbenium ion intermediates like 1-hydroxyethane or 1-methoxyethane ions, contrasts with the well-established Lewis acid-catalyzed MPV process. Based on reactant adsorption modes, we propose two distinct reaction routes for BAS-MPV reduction, bridging the gap between direct and hydrocarbon pool mechanisms in methanol conversion. We further demonstrate the applicability of this pathway to acetone, highlighting its broader role in the early stages of the reaction. A complete understanding of the competing reaction pathways in methanol conversion over zeolites remains elusive. Here the authors explore a Brønsted acid site (BAS)-mediated Meerwein–Ponndorf–Verley (MPV) reduction pathway within ZSM-5 zeolites, facilitating the conversion of acetaldehyde to ethene. [ABSTRACT FROM AUTHOR]

The emergence of global warming issues has triggered the interest in producing carbon-neutral energy sources and fossil-based chemicals from affordable and renewable feedstocks (e.g., bio-ethanol). Herein, the synthesis of highly dispersed CuS/TiO 2 photothermal catalysts is reported for simultaneously converting ethanol into hydrogen and acetaldehyde under simulated sunlight. The catalyst achieved a hydrogen evolution rate of 51.61 mmol g−1 h−1 and an acetaldehyde production rate of 48.63 mmol g−1 h−1, with a maximal acetaldehyde selectivity of 97% among carbon-containing products. Compared to pristine TiO 2 , the introduction of plasmonic CuS largely extended the light adsorption range and enhanced the photothermal performance, whilst the formation of heterojunction structure improved the charge transfer and separation efficiency. The density functional theory calculation results demonstrate that CuS/TiO 2 composite interfaces could significantly lower the activation energy of ethanol dehydrogenation reaction and improve hydrogen evolution reaction ability. This study provides deep insight into understanding and optimizing hot carrier dynamics in photothermal catalytic systems. • Novel CuS/TiO 2 catalyst for efficient ethanol dehydrogenation to co-produce hydrogen and acetaldehyde under mild conditions. • 0.05 CuS/TiO 2 achieved a H 2 evolution rate of 51.61 mmol g−1 h−1 and an acetaldehyde production rate of 48.63 mmol g−1 h−1. • Synergistic effects of heterojunction and significant photothermal effect induced by CuS enhanced catalytic performance. • Reduced activation energy for ethanol dehydrogenation and improved H 2 evolution were achieved by CuS/TiO2 interface. [ABSTRACT FROM AUTHOR]

Protective effect of quercetin against acetaldehyde was evaluated using the cultured hepatocyte models with aldehyde dehydrogenase (ALDH) isozyme deficiency (aldh2-kd and aldh1a1-kd). The quercetin-induced cytoprotection against acetaldehyde in the ALDH1A1-deficient mutant (aldh1a1-kd) was weaker than that in the wild type. Furthermore, quercetin did not enhance the ALDH activity in aldh1a1-kd cells, suggesting that ALDH1A1 is involved in quercetin-induced cytoprotection. [ABSTRACT FROM AUTHOR]

Alcoholic beverages are widely consumed around the world. However, excessive alcohol consumption is harmful to human health, which can cause a series of health problems. Herbals with antioxidant activity as antialcoholic agents have a long history in Asia. In this study, we made a Noni complex beverage (NCB) using Noni and nine other plant materials, which has a potential antialcoholic effect. The total flavonoid content (TFC) and total phenolic content (TPC) were analyzed, and then the antioxidant activities in vitro and antialcoholic effects in vivo were assessed. The results showed that NCB contains TFC of 0.543 ± 0.001 mg/mL and TPC of 1.685 ± 0.029 mg/mL, with significant antioxidant activity in vitro. Furthermore, NCB also showed a good antialcoholic effect in mice. Whether before or after alcohol intake, the consumption of NCB could significantly extend the drunken latency time, shorten the sobriety time, and decrease the blood alcohol concentration compared with the model group. Analysis of the antialcoholic mechanism demonstrated that NCB can remarkably increase the activity of superoxide dismutase, improve glutathione level, and reduce malondialdehyde content, thereby combating oxidative stress caused by alcohol, maintaining the stability of the intracellular antioxidant defense system, and alleviating liver damage; In addition, NCB can upregulate the activities of alcohol dehydrogenase and acetaldehyde dehydrogenase and accelerate alcohol metabolism, thus decreasing the blood alcohol concentration, shortening the sobriety time, and lowering the risk of liver damage caused by alcohol. Taken together, NCB has the potential to be developed as an important natural antialcoholic functional beverage. [ABSTRACT FROM AUTHOR]

Background: Alcohol use, even in moderation, causes hangover discomforts. It has been reported that alcohol-associated symptoms can be improved by either probiotics or medicinal plant extracts to some extent. However, the effects of a combination of multi-strain probiotics, prebiotic, and plant extracts have not been fully explored. Objective: Our main goal is to assess behavioral responses and alcohol metabolism in zebrafish treated with a combination of multi-strain probiotics, prebiotic, and plant extracts after ethanol administration. Methods: In this study, the zebrafish were first treated with the probiotic-prebiotic-plant extract mixture, and then was exposed to different levels of ethanol. The moving distance and activities of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) of zebrafish were measured after ethanol treatment. Results: This probiotic-prebiotic-plant extract mixture significantly improved total distance moved and activities of ADH and ALDH in zebrafish treated with either 1.5% or 4.0% ethanol. In particular, the mixture outperformed plant extracts (both at 250 µg/mL) in total distance moved under 1.5% ethanol administration and degrading acetaldehyde under 4.0% ethanol treatment. Conclusion: A combination of probiotics, prebiotic, and plant extracts effectively mitigated hangover symptoms in cases of moderate and heavy alcohol use and demonstrated superior performance in acetaldehyde metabolism compared to plant extracts alone after heavy drinking, based on a zebrafish model. [ABSTRACT FROM AUTHOR]

Recently, non-Saccharomyces yeasts have gained considerable attention as a novel strategy to enhance the aroma diversity of alcoholic beverages. This study explores the effect of sequential fermentations involving Lachancea thermotolerans and Torulaspora delbrueckii on the aroma profile of apple spirits. Additionally, the influence of time, temperature, and alcohol content on the volatile composition during the maturation of distillates was described. The results revealed that distillates obtained from mixed cultures exhibited improved aroma complexity, primarily due to increased ester production. Torulaspora delbrueckii positively influenced the synthesis of 2-phenethyl acetate, diethyl succinate, and hexyl acetate. Lachancea thermotolerans promoted the formation of ethyl lactate, ethyl myristate, and ethyl phenylacetate while reducing the concentration of higher alcohols. During maturation, changes in aroma constituents were observed. In general, the concentration of the investigated volatile compounds tends to decrease during maturation, with this trend being strongly related to the alcohol content of the distillates. Temperature did not affect the variations of methanol, acetaldehyde, 1-propanol, 2-butanol, 2-methyl-1-butanol, cis-2-hexen-1-ol, and diethyl succinate. Regarding esters, increases were observed in the concentration of ethyl octanoate, ethyl myristate, and, under certain circumstances, ethyl acetate and isoamyl acetate. No correlation was found between changes in acetaldehyde and the conditions tested. [ABSTRACT FROM AUTHOR]

Copyright of China Fiber Inspection / Zhongguo Xian-Jian is the property of China Fiber Inspection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The definition of alcohol hangovers refers to a combination of mental and physical side effects that occur after drinking. One of the ways that hangovers can be ameliorated is by promoting the rapid and effective elimination of acetaldehyde to alleviate the discomfort it causes. This study aimed to investigate the effects of GSH (yeast extract containing 50 mg of glutathione) on the hangover-relieving effect. Methods: A randomized double-blind placebo-controlled crossover clinical trial was conducted with 40 participants who reported experiencing hangover symptoms. Participants consumed alcohol at a rate of 0.78 g per kg body weight with 40% whiskey, adjusted according to their weight. Alcohol and acetaldehyde concentrations in serum were analyzed at 0, 0.25, 1, 2, 4, 6, and 15 h after alcohol consumption. Results: In the GSH group, the serum alcohol concentration decreased, although this change was not statistically significant. The serum acetaldehyde concentration was significantly lower in the GSH group in comparison to the placebo group (at 0.25, 1, 4, and 6 h (p < 0.01) and at 0.5, 2, and 15 h (p < 0.001) after alcohol consumption). However, there was no significant difference between the two groups on questionnaires such as the Acute Hangover Scale and the Alcohol Hangover Severity Scale. Conclusions: Overall, we consider the discovery that GSH lowered acetaldehyde concentration, a crucial factor in alcohol metabolism, to be more considerable. Therefore, GSH administration effectively reduces acetaldehyde levels in serum. This result suggests that this effect may contribute to the relief of hangover symptoms. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chemometric evaluation of potentially harmful volatile compound and toxic metal(loid) distribution patterns in fruit spirits relating to distinct fruit classes most commonly used in spirit production highlighted the potential of several volatiles as candidates for differentiation markers while dismissing toxic metal(loid)s. Pome fruit and grape pomace spirits were mostly characterized by a lower abundance of n-propanol, methanol, ethyl acetate and acetaldehyde, while stone fruit spirits contained lower amounts of isoamyl alcohol and isobutanol. Chemometric analysis of the fruit spirit composition of aromatics identified additional potential markers characteristic for certain fruits—benzoic acid ethyl ester, benzyl alcohol, benzaldehyde, butanoic acid 3-methyl-ethyl ester, butanoic acid 2-methyl-ethyl ester and furfural. This study explored the variability in the risk potential of the investigated spirits, considering that some chemicals known to be detected in spirits are potent health hazards. Ethyl carbamate in combination with acetaldehyde showed a higher potential risk in stone fruit spirits, methanol in stone and pome fruit spirits and acetaldehyde in grape pomace spirits. It is of great interest to evaluate to what extent consumers' preference for spirits of distinct fruit types affects health risks. Consumers of stone fruit spirits are potentially at higher risk than those consuming pome fruit or grape pomace spirits. [ABSTRACT FROM AUTHOR]

This study presents a GIS-based on-road vehicular emission inventory from the tailpipe, brake wear, tire wear and road dust resuspension due to vehicles plying on the road in the city of Lucknow. From the tailpipe, carbon monoxide (CO), sulphur dioxide (SO2), Particulate Matter (PM), oxides of Nitrogen (NOx), 1,3 Butadiene, Total aldehyde and Total PAH emissions were estimated. From the non-exhaust (brake wear and tire wear) and road dust resuspension PM10, PM2.5, and heavy metals were estimated. PM, SO2, NOx, and CO, emissions from the tailpipe are estimated to be 5.8, 0.2, 58, and 141 tons/day respectively. 1,3 Butadiene, Formaldehyde, Acetaldehyde, Total aldehyde, and Total PAH emission are estimated to be 575, 853, 113, 1468, and 57,542 gm/day respectively. PM10 and PM2.5 emission from road dust resuspension in Lucknow city was estimated to be 155 tons/day and 37 tons/day respectively. The results show that PM10 emission from road dust resuspension is 27 times higher as compared to tailpipe emission. This indicates inadequate road conditions or high silt loads in the city of Lucknow. Priority should be given to reducing silt load on roads while developing a PM mitigation plan or policy for air pollution control. [ABSTRACT FROM AUTHOR]

The consumption of red wine induces headaches in some subjects who can drink other alcoholic beverages without suffering. The cause for this effect has been attributed to a number of components, often the high level of phenolics in red wine, but a mechanism has been elusive. Some alcohol consumers exhibit flushing and experience headaches, and this is attributed to a dysfunctional ALDH2 variant, the enzyme that metabolizes acetaldehyde, allowing it to accumulate. Red wine contains much higher levels of quercetin and its glycosides than white wine or other alcoholic beverages. We show that quercetin-3-glucuronide, a typical circulating quercetin metabolite, inhibits ALDH2 with an IC50 of 9.6 µM. Consumption of red wine has been reported to result in comparable levels in circulation. Thus, we propose that quercetin-3-glucoronide, derived from the various forms of quercetin in red wines inhibits ALDH2, resulting in elevated acetaldehyde levels, and the subsequent appearance of headaches in susceptible subjects. Human-subject testing is needed to test this hypothesis.

Abstract Background Aldehyde dehydrogenase 2 (ALDH2) is critical for alcohol metabolism by converting acetaldehyde to acetic acid. In East Asian descendants, an inactive genetic variant in ALDH2, rs671, triggers an alcohol flushing response due to acetaldehyde accumulation. As alcohol flushing is not exclusive to those of East Asian descent, we questioned whether additional ALDH2 genetic variants can drive facial flushing and inefficient acetaldehyde metabolism using human testing and biochemical assays. Methods After IRB approval, human subjects were given an alcohol challenge (0.25 g/kg) while quantifying acetaldehyde levels and the physiological response (heart rate and skin temperature) to alcohol. Further, by employing biochemical techniques including human purified ALDH2 proteins and transiently transfected NIH 3T3 cells, we characterized two newly identified ALDH2 variants for ALDH2 enzymatic activity, ALDH2 dimer/tetramer formation, and reactive oxygen species production after alcohol treatment. Results Humans heterozygous for rs747096195 (R101G) or rs190764869 (R114W) had facial flushing and a 2-fold increase in acetaldehyde levels, while rs671 (E504K) had facial flushing and a 6-fold increase in acetaldehyde levels relative to wild type ALDH2 carriers. In vitro studies with recombinant R101G and R114W ALDH2 enzyme showed a reduced efficiency in acetaldehyde metabolism that is unique when compared to E504K or wild-type ALDH2. The effect is caused by a lack of functional dimer/tetramer formation for R101G and decreased Vmax for both R101G and R114W. Transiently transfected NIH-3T3 cells with R101G and R114W also had a reduced enzymatic activity by ~ 50% relative to transfected wild-type ALDH2 and when subjected to alcohol, the R101G and R114W variants had a 2-3-fold increase in reactive oxygen species formation with respect to wild type ALDH2. Conclusions We identified two additional ALDH2 variants in humans causing facial flushing and acetaldehyde accumulation after alcohol consumption. As alcohol use is associated with a several-fold higher risk for esophageal cancer for the E504K variant, the methodology developed here to characterize ALDH2 genetic variant response to alcohol can lead the way precision medicine strategies to further understand the interplay of alcohol consumption, ALDH2 genetics, and cancer.

Detailed experimental and computational studies of the nitrone 3,3‐dimethyl‐6‐phenyl‐2,3‐dihydro‐1,2,4‐triazin‐4‐oxide (2), which is a cyclized product of an open‐chain isomer 2‐phenyl‐2‐(propan‐2‐ylidenehydrazono)acetaldehyde oxime (1), are reported. The isolated compound 2 was characterized by elemental analysis, powder X‐ray diffraction, IR and UV‐vis spectroscopy, and spectrofluorometry. Electronic properties of 1 and 2 were elucidated by the DFT‐based calculations in water, which revealed that both compounds are pronounced electrophiles. The ADMET properties of the oxime 1 and nitrone 2 were predicted using the SwissADME, which includes the BOILED‐Egg method, and ProTox‐II online tools. Using a molecular docking approach, the discussed compounds were also predicted to actively interact with all the studied herein SARS‐CoV‐2 proteins. The most pronounced activity for both discussed compounds was established with Nonstructural protein 14 (Nsp14_N7‐MTase). Complex Nsp14_N7‐MTase‐1 is characterized by the calculated ligand efficiency scores being close for a Hit. [ABSTRACT FROM AUTHOR]

Due to the forensic aspects of drinking and exposure to toxic substances, more sophisticated quantitative technology is needed to quantify the concentration of ethyl alcohol and acetaldehyde in the blood. In this study, we developed a headspace gas chromatography tandem mass spectrometry method that could simultaneously detect ethyl alcohol and acetaldehyde in human plasma. Through a simple preparation process, ethyl alcohol and acetaldehyde were quickly detected within 4 min, and a lower limit of quantification (LLOQ) (20 and 0.2 µg/mL) was obtained; these results confirmed the suitability of the system. According to Food and Drug Administration guidelines, the linearity (correlation coefficient > 0.9996), intraday and intraday accuracy, precision, and both short- and long-term stability and freeze-thaw stability satisfied the evaluation criteria (within 100.0 ± 15.0% and 20.0% of the LLOQ). Carryover and batch size assessment for the evaluation of the sample influence during analysis also satisfied the evaluation criteria. A valid method was applied to the pharmacokinetics study, and the plasma from 43 subjects after oral administration of the placebo or HK-GCM-H01 was analyzed. The developed analysis method for ethyl alcohol and acetaldehyde in blood could be used in various fields, such as forensics and those requiring precise quantification. [ABSTRACT FROM AUTHOR]

A hangover is a combination of negative mental and physical symptoms, such as headache, diarrhea, and loss of appetite, that occur after alcohol consumption and can vary depending on individual genetic and environmental factors. To quickly relieve these hangover symptoms, a new hangover relief compound called HK-GCM-H01 has been developed. This compound, HK-GCM-H01, consists of fermented rice germ extracts, yeast extract mixtures, cili extract powder, and concentrated nipafam powder, all of which are known to relieve hangover symptoms. The safety and clinical symptoms of HK-GCM-H01 were evaluated, along with the pharmacokinetic properties of alcohol and acetaldehyde after its administration. This study was conducted on 50 healthy Korean men using a randomized, double-blind, placebo-controlled, single-intake, crossover design. To evaluate clinical symptoms, Acute Hangover Scale and Alcohol Hangover Severity Scale were used, and the pharmacokinetic evaluation parameters included the maximum plasma concentration, the time to peak plasma concentration, the terminal half-life, and the area under the plasma concentration-time curve from X hours to Y hours. A significant reduction in clinical symptoms was observed after alcohol consumption in the group that consumed HK-GCM-H01 with added hangover relief compound, as was a significant decrease in blood exposure to acetaldehyde compared to the placebo group. There were no adverse events or significant changes in liver function indicators reported during the safety evaluation. These findings indicate that HK-GCM-H01 is safe and significantly reduces plasma concentrations of acetaldehyde, the main cause of hangover, suggesting that it improves hangover symptoms. [ABSTRACT FROM AUTHOR]

Redox homeostasis is the balance between oxidation and reduction reactions. Its maintenance depends on glutathione, including its reduced and oxidized form, GSH/GSSG, which is the main intracellular redox buffer, but also on the nicotinamide adenine dinucleotide phosphate, including its reduced and oxidized form, NADPH/NADP+. Under conditions that enable yeast cells to undergo fermentative metabolism, the main source of NADPH is the pentose phosphate pathway. The lack of enzymes responsible for the production of NADPH has a significant impact on yeast cells. However, cells may compensate in different ways for impairments in NADPH synthesis, and the choice of compensation strategy has several consequences for cell functioning. The present study of this issue was based on isogenic mutants: Δzwf1, Δgnd1, Δald6, and the wild strain, as well as a comprehensive panel of molecular analyses such as the level of gene expression, protein content, and enzyme activity. The obtained results indicate that yeast cells compensate for the lack of enzymes responsible for the production of cytosolic NADPH by changing the content of selected proteins and/or their enzymatic activity. In turn, the cellular strategy used to compensate for them may affect cellular efficiency, and thus, the ability to grow or sensitivity to environmental acidification. [ABSTRACT FROM AUTHOR]

3,3,3-Trifluoro-1,2-propanediol undergoes complete defluorination in two distinct steps: first, the conversion into 3,3,3-trifluoropropionaldehyde catalyzed by adenosylcobalamin (coenzyme B 12 )-dependent diol dehydratase; second, non-enzymatic elimination of all three fluorides from this aldehyde to afford malonic semialdehyde (3-oxopropanoic acid), which is decarboxylated to acetaldehyde. Diol dehydratase accepts 3,3,3-trifluoro-1,2-propanediol as a relatively poor substrate, albeit without significant mechanism-based inactivation of the enzyme during catalysis. Optical and electron paramagnetic resonance (EPR) spectra revealed the steady-state formation of cob(II)alamin and a substrate-derived intermediate organic radical (3,3,3-trifluoro-1,2-dihydroxyprop-1-yl). The coenzyme undergoes Co–C bond homolysis initiating a sequence of reaction by the generally accepted pathway via intermediate radicals. However, the greater steric size of trifluoromethyl and especially its negative impact on the stability of an adjacent radical centre compared to a methyl group has implications for the mechanism of the diol dehydratase reaction. Nevertheless, 3,3,3-trifluoropropionaldehyde is formed by the normal diol dehydratase pathway, but then undergoes non-enzymatic conversion into acetaldehyde, probably via 3,3-difluoropropenal and malonic semialdehyde. [ABSTRACT FROM AUTHOR]

The effect of small fractions of acetaldehyde (CH3CHO) on the ignition delay time of methane (CH4) was examined at high pressure. Measurements are reported for the ignition delay time obtained in a rapid compression machine (RCM) at a compression pressure (Pc) of ∼60 bar and temperatures after compression (Tc) in the range 750–900 K for fuel‐air equivalence ratios ϕ in the range 1–4. The results show that mixtures of 2%–5% CH3CHO in CH4 ignite under conditions at which pure methane does not ignite experimentally. The efficiency of acetaldehyde as a promoter seems to be comparable to that of other oxygenated fuels like alcohols and ethers. For comparison with the experimental results, ignition delay times are computed using an updated reaction mechanism and two mechanisms from the literature for CH3CHO oxidation. For most conditions, the simulations using the current mechanism agree with the measurements to within a factor of two. The ignition profile shows a pre‐ignition temperature rise and two‐stage ignition similar to that previously observed in low fractions of dimethyl ether in ammonia; both phenomena are captured by the simulations. Analysis of simulations at constant volume indicates that CH3CHO is oxidized much more rapidly than CH4, producing reactive species that initiate the oxidation of CH4 and generates heat that accelerates oxidation toward ignition. The low‐temperature chain‐branching reactions of CH3CHO are important in the early oxidation of the fuel mixture. Additional simulations were performed for equivalence ratios of ϕ = 1 and 4, at a compression pressure (Pc) of 100 bar and Tc = 750–1000 K. The simulations indicate that CH3CHO has a strong ignition‐enhancing effect on CH4, with small fractions reducing the ignition delay time by up to a factor of 100, depending on the temperature, as compared to pure CH4. [ABSTRACT FROM AUTHOR]

L-threo-methylsulonylphenylserine (L-threo-MSPS) is a crucial intermediate in florphenicol and thiamphenicol synthesis. L-threo-MSPS can be synthesized from L-threonine and p-methylsulfonylbenzaldehyde (p-MSBA) chiral selectively under the catalyse of L-threonine transaldolase. However, the byproduct acetaldehyde formed during the reaction process severely hinders the biosynthesis of high-quality L-threo-MSPS. The accumulated acetaldehyde reacts with L-thero-MSPS and L-threonine to form N-derivatives, and the activity of L-threonine transaldolase decreases to 14.10% even when the concentration of acetaldehyde is as low as 0.5 g/L. The acetaldehyde could be removed by aeration, and the removal efficiency is closely related to the aeration conditions, which was described by the volumetric oxygen transfer coefficient k L a in this paper. Regular aeration through pipes cannot provide enough aeration efficiency, and filters or sintered rods were used to increase the k L a value during the reaction. The residual concentration of acetaldehyde depended on the balance between the formation and removal speed of acetaldehyde. When the optimal enzyme concentration was applied and the k L a value of 5.5 min-1, the L-threo-MSPS concentration reached 293.28 mM in a 1-L reaction, and the highest conversion reached 90.03%. The need of coenzyme NAD+ was cut off in this method, and only one enzyme was applied. Consequently, the reaction was simpler and easier to control. [Display omitted] • NAD+-independent biosynthesis of L-threo-MSPS with transaldolase and aeration. • The derivatization of L-threo-MSPS and L-threonine by acetaldehyde in the reaction. • The relation between acetaldehyde removal efficiency and the kLa value of aeration. • Increased conversion of L-threo-MSPS from 60% to 90% by aeration. [ABSTRACT FROM AUTHOR]

Plant growth regulators are an appealing and fast-track method for overcoming the drastic effects of drought. Paclobutrazol (PBZ), a member of the triazole family, is a versatile chemical compound that acts as a growth regulator and retardant. This study assessed the effect of two concentrations of PBZ (30 and 60 mg L–1) on strawberry plants under two drought stress levels [40% and 80% field capacity (FC)] and 100% FC set as the control. The findings revealed that drought significantly affected strawberry plants, elevating the levels of reactive oxygen species (ROS) like hydrogen peroxide (H2O2), hydroxide ion (OH–), and superoxide ion (O2–), and reactive carbonyl species (RCS) like malondialdehyde (MDA), methylglyoxal (MG), 4-hydroxy-(E)-2-hexenal (HEE), acetone, propionaldehyde (PD), acetaldehyde (ACD), and formaldehyde (FMD), due to decreased antioxidant activities. The study also found that glutathione (GSH) is crucial in ROS and RCS scavenging. In addition, the presence of thiol groups (–SH compounds) in strawberry plants under moderate and severe drought stress was a noteworthy finding. Due to excess thiol production, drought stress significantly decreased MDA, MG, HEE, PD, ACD, FMD, and acetone levels. However, PBZ application decreased the total thiol content in strawberry leaves. Furthermore, PBZ improved plant growth and development by modulating the production of endogenous growth hormones such as abscisic acid, indole-3-acetic acid, ethylene, gibberellic acid, strigolactones, and brassinosteroids, while increasing cytokinin levels. These changes led to enhanced enzymatic and non-enzymatic antioxidant activities, reduced stomatal conductance, increased relative water content in leaves, improved chlorophyll content, elevated photosynthetic rate, and ultimately enhanced increased fruit yield. Moreover, drought stress enhanced metabolic activity (α-tocopherol, β-carotene, total phenolic content, anthocyanin, and proline) in strawberry plants, indicating that metabolites also function as stress scavengers/protectors. This study shed light on crucial physiological mechanisms underlying ROS- and RCS-induced oxidative stresses and their management in strawberry plants. [ABSTRACT FROM AUTHOR]

It is still unclear whether or how quercetin influences the toxic events induced by acetaldehyde in hepatocytes, though quercetin has been reported to mitigate alcohol-induced mouse liver injury. In this study, we evaluated the modulating effect of quercetin on the cytotoxicity induced by acetaldehyde in mouse hepatoma Hepa1c1c7 cells, the frequently used cellular hepatocyte model. The pretreatment with quercetin significantly inhibited the cytotoxicity induced by acetaldehyde. The treatment with quercetin itself had an ability to enhance the total ALDH activity, as well as the ALDH1A1 and ALDH3A1 gene expressions. The acetaldehyde treatment significantly enhanced the intracellular reactive oxygen species (ROS) level, whereas the quercetin pretreatment dose-dependently inhibited it. Accordingly, the treatment with quercetin itself significantly up-regulated the representative intracellular antioxidant-related gene expressions, including heme oxygenase-1 (HO-1), glutamate-cysteine ligase, catalytic subunit (GCLC), and cystine/glutamate exchanger (xCT), that coincided with the enhancement of the total intracellular glutathione (GSH) level. Tin protoporphyrin IX (SNPP), a typical HO-1 inhibitor, restored the quercetin-induced reduction in the intracellular ROS level, whereas buthionine sulphoximine, a representative GSH biosynthesis inhibitor, did not. SNPP also cancelled the quercetin-induced cytoprotection against acetaldehyde. These results suggest that the low-molecular-weight antioxidants produced by the HO-1 enzymatic reaction are mainly attributable to quercetin-induced cytoprotection. [ABSTRACT FROM AUTHOR]

This study investigates polyaniline (PANI) for its sensing characteristics for detecting acetaldehyde. Pristine PANI is further modified in two ways to improve its sensing capabilities: 1) addition of a side chain (i.e., two methyl groups) to form poly (2,5‐dimethylaniline), 2) addition of small amounts of metal oxide dopant (In2O3 in this case) to PANI. All the materials are evaluated for their sensing characteristics with respect to both sensitivity and selectivity. The sensitivity of PANI toward acetaldehyde is found to improve with both types of modification (i.e., poly (2,5‐dimethylaniline) and PANI doped with different wt.% of In2O3). However, upon evaluating selectivity toward acetaldehyde using binary and ternary gas mixtures, pristine PANI exhibited higher selectivity compared to its modified counterparts. [ABSTRACT FROM AUTHOR]

The fraction of urban volatile organic compound (VOC) emissions attributable to fossil fuel combustion has been declining in many parts of the world, resulting in a need to better constrain other anthropogenic sources of these emissions. During the National Institute of Environmental Research (NIER) and National Aeronautics and Space Administration (NASA) Korea-United States Air Quality (KORUS-AQ) field study in Seoul, South Korea, during May–June 2016, air quality models underestimated ozone, formaldehyde, and peroxyacetyl nitrate (PAN), indicating an underestimate of VOCs in the emissions inventory. Here, we use aircraft observations interpreted with the GEOS-Chem chemical transport model (version 13.4.0) to assess the need for increases in VOC emissions and for a revised chemical mechanism to improve treatment of VOC speciation and chemistry. We find that the largest needed VOC emissions increases are attributable to compounds associated with volatile chemical products, liquefied petroleum gas (LPG) and natural gas emissions, and long-range transport. Revising model chemistry to better match observed VOC speciation together with increasing model emissions of underestimated VOC species increased calculated OH reactivity by + 2 s -1 and ozone production by + 2 ppb h -1. Ozone increased by + 6 ppb below 2 km and + 9 ppb at the surface, and formaldehyde and acetaldehyde increased by + 30 % and + 120 % aloft, respectively, all in better agreement with observations. The larger increase in acetaldehyde was attributed to ethanol emissions, which we found to be as important for ozone production as isoprene or alkenes. The increased acetaldehyde significantly reduced the model PAN bias. The need for additional unmeasured VOCs, however, was indicated by a remaining model bias of - 0.8 ppb in formaldehyde and a - 57 % and - 52 % underestimate in higher peroxynitrates (PNs) and alkyl nitrates (ANs), respectively. We added additional chemistry to the model to represent an additional six PNs from observed VOCs but were unable to account for the majority of missing PNs. However, four of these PNs were modeled at concentrations similar to other commonly measured PNs (> 2 % of PAN) indicating that these should be measured in future campaigns and considered from other VOC emission sources (e.g., fires). We hypothesize that emissions of oxygenated VOCs (OVOCs) such as ≥ C5 aldehydes from cooking and/or alkenes associated with volatile chemical products could produce both PNs and ANs and improve remaining model biases. Emerging research on the emissions and chemistry of these species will soon allow for modeling of their impact on local and regional photochemistry. [ABSTRACT FROM AUTHOR]

Microbial contamination of food and alimentary toxoinfection/intoxication in humans are commonly caused by bacteria such as Salmonella spp., Escherichia coli, Yersinia spp., Campylobacter spp., Listeria monocytogenes, and fungi (Aspergillus, Fusarium). The addition of probiotic cultures (bacterial strains Lactobacillus and Bifidobacterium and the yeast Saccharomyces cerevisiae var. boulardii) to food contributes primarily to food enrichment and obtaining a functional product, but also to food preservation. Reducing the number of viable pathogenic microorganisms and eliminating or neutralizing their toxins in food is achieved by probiotic-produced antimicrobial substances such as organic acids (lactic acid, acetic acid, propionic acid, phenylacetic acid, and phenyllactic acid), fatty acids (linoleic acid, butyric acid, caproic acid, and caprylic acid), aromatic compounds (diacetyl, acetaldehyde, reuterin), hydrogen peroxide, cyclic dipeptides, bacteriocins, and salivabactin. This review summarizes the basic facts on microbial contamination and preservation of food and the potential of different probiotic strains and their metabolites (postbiotics), including the mechanisms of their antimicrobial action against various foodborne pathogens. Literature data on this topic over the last three decades was searched in the PubMed, Scopus, and Google Scholar databases, systematically presented, and critically discussed, with particular attention to the advantages and disadvantages of using probiotics and postbiotics as food biopreservatives. [ABSTRACT FROM AUTHOR]

This open-labeled and comparative study aimed to test the efficacy and safety of a fermented rice extract-based substance containing yeast-fermented powder having aldehyde dehydrogenase (KisLip®, Pico Entech, Republic of Korea) in healthy male individuals. Healthy male subjects (n = 20) consumed 90 g of alcohol at their first visit. At the second visit, participants consumed 90 g of alcohol or alcohol with a low dose of KISLip® (2000 mg, KL-L) and then 90 g of alcohol or alcohol with a high dose of KISLip® (3000 mg, KL-H) at the third visit. The efficacy of KISLip® depends on the mutational status of important genes related to alcohol metabolism, including alcohol dehydrogenase (ADH1B), cytochrome P4502E1 (CYP2E1 (5B) and CYP2E1 (6)), and aldehyde dehydrogenase (ALDH2). KISLip® significantly reduced the highest level (Cmax) of alcohol and overall levels of acetaldehyde compared to the alcohol-only group in a dose-dependent manner. These significant effects of KISLip® on alcohol metabolism were observed independent of mutations in the four genes. In addition, hangover symptoms were significantly decreased in the KISLip® treated groups. During the study, the participants did not show any adverse events after KISLip® intake. This clinical study suggested that supplementation of KISLip® had beneficial effects on alcohol metabolism and might ameliorate the severity of hangovers without any adverse events. [ABSTRACT FROM AUTHOR]

Aminoacetaldehyde (glycinal, NH2CH2CHO) is a first-generation oxidation product of monoethanolamine (MEA, NH2CH2CH2OH), a solvent widely used for CO2 gas separation, which is proposed as the basis for a range of carbon capture technologies. A complete oxidation mechanism for MEA is required to understand the atmospheric transformation of carbon capture plant emissions, as well as the degradation of this solvent during its use and the oxidative destruction of waste solvent. In this study, we have investigated the •OH radical-initiated oxidation chemistry of aminoacetaldehyde using quantum chemical calculations and RRKM theory/master equation kinetic modeling. This work predicts that aminoacetaldehyde has a tropospheric lifetime of around 6 h and that the reaction predominantly produces the NH2CH2C•O radical intermediate at room temperature, along with minor contributions from NH2•CHCHO and •NHCH2CHO. The dominant radical intermediate NH2CH2C•O is predicted to promptly dissociate to NH2•CH2 and CO, where NH2•CH2 is known to react with O2 under tropospheric conditions to form the imine NH = CH2 + HO2. The NH2•CHCHO radical experiences captodative stabilization and is found to form a weakly bound peroxyl radical upon reaction with O2. Instead, the major oxidation product of NH2•CHCHO and the aminyl radical •NHCH2CHO is the imine NH = CHCHO (+HO2). In the atmosphere, the dominant fate of imine compounds is thought to be hydrolysis, where NH = CH2 will form ammonia and formaldehyde, and NH = CHCHO will produce ammonia and glyoxal. Efficient conversion of the dominant first-generation oxidation products of MEA to ammonia is consistent with field observations and supports the important role of imine intermediates in MEA oxidation. [ABSTRACT FROM AUTHOR]

The non-oxidative dehydrogenation of ethanol into acetaldehyde is one of the efficient solutions for biomass upgrading. In this work, a series of copper catalysts supported on MgO with different Cu loadings ranging from 2.5% to 20% were prepared by an impregnation method. The as-synthesized Cu/MgO catalysts were characterized by N2 adsorption, XRD, TEM, CO2-TPD, XPS and TPR. These catalysts were found to be effective for ethanol dehydrogenation into acetaldehyde. As the Cu loading was increased, the ethanol conversion first increased and then leveled off. At a WHSV of 1.5 h−1 and 250 °C, the 20%Cu/MgO catalyst gave an initial conversion of 81.5%, with 97.7% selectivity toward acetaldehyde. Compared to 20%Cu/SiO2, the 20%Cu/MgO catalyst displayed an equivalent initial acetaldehyde yield, higher acetaldehyde selectivity and longer stability. [ABSTRACT FROM AUTHOR]

TiO2 photocatalysts were synthesized by simple sol gel method and annealed at 300, 500, and 600°C. Photocatalytic performance of as‐prepared TiO2 and annealed TiO2 samples was evaluated for the decomposition of acetaldehyde under UV light irradiation. TiO2 annealed at 500°C (T500) showed the highest acetaldehyde removal performance, which was attributed to combined effects of its crystallinity, defect density, surface area, narrow band gap with the dual phase of TiO2, and lifetimes of charge carriers. In humid conditions, overall acetaldehyde removal performance of T500 slightly decreased, but the extent of total oxidation of acetaldehyde into CO2 increased in high humidity as compared to dry conditions. Moreover, fixation of T500 on mica sheet using binders resulted in promising photocatalytic performance, making it a potential candidate for air purification applications. Fourier‐transform infra‐red (FT‐IR) analysis confirmed the stable existence of binder structure under dry air and UV treatment, which is crucial for real applications. [ABSTRACT FROM AUTHOR]

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Acetaldehyde (AL), a primary carcinogen, not only pollutes the environment, but also endangers human health after drinking alcohol. Here a promising bacterial strain was successfully isolated from a white wine cellar pool in the province of Shandong, China, and identified as Bacillus velezensis-YW01 with 16 S rDNA sequence. Using AL as sole carbon source, initial AL of 1 g/L could be completely biodegraded by YW01 within 84 h and the cell-free extracts of YW01 has also been detected to biodegrade the AL, which indicate that YW01 is a high-potential strain for the biodegradation of AL. The optimal culture conditions and the biodegradation of AL of YW01 are at pH 7.0 and 38 °C, respectively. To further analyze the biodegradation mechanism of AL, the whole genome of YW01 was sequenced. Genes ORF1040, ORF1814 and ORF0127 were revealed in KEGG, which encode for acetaldehyde dehydrogenase. Furthermore, ORF0881 and ORF052 encode for ethanol dehydrogenase. This work provides valuable information for exploring metabolic pathway of converting ethanol to AL and subsequently converting AL to carboxylic acid compounds, which opened up potential pathways for the development of microbial catalyst against AL. [ABSTRACT FROM AUTHOR]

Acetaldehyde is a volatile organic compound that can cause damage at the cellular and genomic levels. The monitoring of acetaldehyde gas at low concentrations requires fast-response and low-cost sensors. Herein, we propose the design of an acetaldehyde gas sensor based on a low-cost Microelectromechanical System (MEMS) process. This sensor is formed by a single-clamped piezoelectric multilayer resonator (3000 × 1000 × 52.2 µm) with a simple operating principle and easy signal processing. This resonator uses a zinc oxide piezoelectric layer (1 µm thick) and a sensing film of titanium oxide (1 µm thick). In addition, the resonator uses a support layer of 304 stainless steel (50 µm thick) and two aluminum layers (100 nm thick). Analytical and Finite-Element Method (FEM) models are developed to predict the mechanical behavior of the gas sensor, considering the influence of the different layers of the resonator. The analytical results agree well with respect to the FEM model results. The gas sensor has a first bending frequency of 4722.4 Hz and a sensitivity of 8.22 kHz/g. A minimum detectable concentration of acetaldehyde of 102 ppm can be detected with the proposed sensor. This gas sensor has a linear behavior to detect different acetaldehyde concentrations using the frequency shifts of its multilayer resonator. The gas sensor design offers advantages such as small size, a light weight, and cost-efficient fabrication. [ABSTRACT FROM AUTHOR]

Saccharomyces cerevisiae LBTF 21.3, Pichia manshurica LBTF 21.1, and Leuconostoc lactis LBTF 21.1 were used as single and mixed cultures in coffee fermentations. Fermentations carried out in glass jars with P. manshurica LBTF 21.1/Leuc. lactis LBTF 21.1 showed higher fermentation rates than S. cerevisiae LBTF 21.3/P. manshurica LBTF 21.1 or S. cerevisiae LBTF 21.3/Leuc. lactis LBTF 21.1. The highest cup quality was reached with P. manshurica LBTF 21.1/Leuc. lactis LBTF 21.1 (83.0 points). Full factorial design (22) carried out with P. manshurica LBTF 21.1 revealed that the higher proportion of water added before the fermentation resulted in higher production of acetic acid. A contrary effect of this variable was observed on the production of lactic acid with Leuc. lactis LBTF 21.1. Fermentations conducted in bioreactor evidenced the production of acetaldehyde by P. manshurica LBTF 21.1/Leuc. lactis LBTF 21.1, P. manshurica LBTF 21.1, and Leuc. lactis LBTF 21.1. Additionally, the highest cup quality was reached in fermentations with P. manshurica LBTF 21.1 (82.5 points) followed by Leuc. lactis LBTF 21.1 (81.5 points) and P. manshurica LBTF 21.1/Leuc. lactis LBTF 21.1 (81.0 points). Fermentations of coffee with single and mixed cultures are interesting strategies for the improvement of the sensory quality. [ABSTRACT FROM AUTHOR]

Background: Aldehyde dehydrogenase 2 (ALDH2) is critical for alcohol metabolism by converting acetaldehyde to acetic acid. In East Asian descendants, an inactive genetic variant in ALDH2, rs671, triggers an alcohol flushing response due to acetaldehyde accumulation. As alcohol flushing is not exclusive to those of East Asian descent, we questioned whether additional ALDH2 genetic variants can drive facial flushing and inefficient acetaldehyde metabolism using human testing and biochemical assays. Methods: After IRB approval, human subjects were given an alcohol challenge (0.25 g/kg) while quantifying acetaldehyde levels and the physiological response (heart rate and skin temperature) to alcohol. Further, by employing biochemical techniques including human purified ALDH2 proteins and transiently transfected NIH 3T3 cells, we characterized two newly identified ALDH2 variants for ALDH2 enzymatic activity, ALDH2 dimer/tetramer formation, and reactive oxygen species production after alcohol treatment. Results: Humans heterozygous for rs747096195 (R101G) or rs190764869 (R114W) had facial flushing and a 2-fold increase in acetaldehyde levels, while rs671 (E504K) had facial flushing and a 6-fold increase in acetaldehyde levels relative to wild type ALDH2 carriers. In vitro studies with recombinant R101G and R114W ALDH2 enzyme showed a reduced efficiency in acetaldehyde metabolism that is unique when compared to E504K or wild-type ALDH2. The effect is caused by a lack of functional dimer/tetramer formation for R101G and decreased Vmax for both R101G and R114W. Transiently transfected NIH-3T3 cells with R101G and R114W also had a reduced enzymatic activity by ~ 50% relative to transfected wild-type ALDH2 and when subjected to alcohol, the R101G and R114W variants had a 2-3-fold increase in reactive oxygen species formation with respect to wild type ALDH2. Conclusions: We identified two additional ALDH2 variants in humans causing facial flushing and acetaldehyde accumulation after alcohol consumption. As alcohol use is associated with a several-fold higher risk for esophageal cancer for the E504K variant, the methodology developed here to characterize ALDH2 genetic variant response to alcohol can lead the way precision medicine strategies to further understand the interplay of alcohol consumption, ALDH2 genetics, and cancer. [ABSTRACT FROM AUTHOR]

Context. The presence of grains is key to the synthesis of molecules in the interstellar medium that cannot form in the gas phase due to its low density and temperature conditions. In these reactions, the role of the grains is to enhance the encounter rate of the reactive species on their surfaces and to dissipate the energy excess of largely exothermic reactions, but less is known about their role as chemical catalysts; namely, bodies that provide low activation energy pathways with enhanced reaction rates. Different refractory materials with catalytic properties, such as those containing space-abundant d-block transition metals like iron (Fe), are present in astrophysical environments. Aims. Here, we report for first time mechanistic insights into the Fischer-Tropsch-type (FTT) synthesis of ethanol (CH3CH2OH), through ketene (CH2CO) and acetaldehyde (CH3CHO) intermediates, and methane (CH4) via a chain growing mechanism using a single-Fe atom supported on silica (SiO2) surfaces as a heterogeneous astrocatalyst. Methods. Quantum chemical simulations based on extended periodic surfaces were carried out to characterize the potential energy surfaces of the FTT chain growing mechanism. Calculations of the binding energies of reaction intermediates and products and Rice–Ramsperger–Kassel–Marcus kinetic calculations were performed to evaluate catalytic efficiencies and determine the feasibility of the reactions in different astrophysical environments. Results. Mechanistic studies demonstrate that the FTT chain growing mechanism enters into direct competition with FTT methanol formation, since formation of the CH2 chain growth initiator is feasible. The coupling of the CH2 with CO (forming ketene) and subsequent H2 additions yield acetaldehyde and finally ethanol, while direct H2 addition to CH2 produces methane. Thermodynamically, both processes are largely exergonic, but they present energy barriers that require external energy inputs to be overcome. Kinetic calculations demonstrate the strong temperature dependency of the FTT processes as tunneling does not dominate. Conclusions. The results could explain the presence of CH3CH2OH and CH4 in diverse astrophysical regions where current models fail to reproduce their observational quantities. The evidence that the chain growing mechanism is operating opens a new reactivity paradigm toward the formation of complex organic molecules, which is constrained by the temperature-dependent behaviour of the FTT reactions and by making their energy features a crucial aspect. [ABSTRACT FROM AUTHOR]