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Dator, Romel P., Morwena J. Solivio, Peter W. Villalta, and Silvia Balbo. "Bioanalytical and Mass Spectrometric Methods for Aldehyde Profiling in Biological Fluids." Toxics 7, no. 2 (June 4, 2019): 32. http://dx.doi.org/10.3390/toxics7020032.
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Human exposure to aldehydes is implicated in multiple diseases including diabetes, cardiovascular diseases, neurodegenerative disorders (i.e., Alzheimer’s and Parkinson’s Diseases), and cancer. Because these compounds are strong electrophiles, they can react with nucleophilic sites in DNA and proteins to form reversible and irreversible modifications. These modifications, if not eliminated or repaired, can lead to alteration in cellular homeostasis, cell death and ultimately contribute to disease pathogenesis. This review provides an overview of the current knowledge of the methods and applications of aldehyde exposure measurements, with a particular focus on bioanalytical and mass spectrometric techniques, including recent advances in mass spectrometry (MS)-based profiling methods for identifying potential biomarkers of aldehyde exposure. We discuss the various derivatization reagents used to capture small polar aldehydes and methods to quantify these compounds in biological matrices. In addition, we present emerging mass spectrometry-based methods, which use high-resolution accurate mass (HR/AM) analysis for characterizing carbonyl compounds and their potential applications in molecular epidemiology studies. With the availability of diverse bioanalytical methods presented here including simple and rapid techniques allowing remote monitoring of aldehydes, real-time imaging of aldehydic load in cells, advances in MS instrumentation, high performance chromatographic separation, and improved bioinformatics tools, the data acquired enable increased sensitivity for identifying specific aldehydes and new biomarkers of aldehyde exposure. Finally, the combination of these techniques with exciting new methods for single cell analysis provides the potential for detection and profiling of aldehydes at a cellular level, opening up the opportunity to minutely dissect their roles and biological consequences in cellular metabolism and diseases pathogenesis.
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Kunjapur, Aditya M., and Kristala L. J. Prather. "Microbial Engineering for Aldehyde Synthesis." Applied and Environmental Microbiology 81, no. 6 (January 9, 2015): 1892–901. http://dx.doi.org/10.1128/aem.03319-14.
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ABSTRACTAldehydes are a class of chemicals with many industrial uses. Several aldehydes are responsible for flavors and fragrances present in plants, but aldehydes are not known to accumulate in most natural microorganisms. In many cases, microbial production of aldehydes presents an attractive alternative to extraction from plants or chemical synthesis. During the past 2 decades, a variety of aldehyde biosynthetic enzymes have undergone detailed characterization. Although metabolic pathways that result in alcohol synthesis via aldehyde intermediates were long known, only recent investigations in model microbes such asEscherichia colihave succeeded in minimizing the rapid endogenous conversion of aldehydes into their corresponding alcohols. Such efforts have provided a foundation for microbial aldehyde synthesis and broader utilization of aldehydes as intermediates for other synthetically challenging biochemical classes. However, aldehyde toxicity imposes a practical limit on achievable aldehyde titers and remains an issue of academic and commercial interest. In this minireview, we summarize published efforts of microbial engineering for aldehyde synthesis, with an emphasis onde novosynthesis, engineered aldehyde accumulation inE. coli, and the challenge of aldehyde toxicity.
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Hellenthal, Katharina E. M., Laura Brabenec, Eric R. Gross, and Nana-Maria Wagner. "TRP Channels as Sensors of Aldehyde and Oxidative Stress." Biomolecules 11, no. 10 (September 24, 2021): 1401. http://dx.doi.org/10.3390/biom11101401.
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The transient receptor potential (TRP) cation channel superfamily comprises more than 50 channels that play crucial roles in physiological processes. TRP channels are responsive to several exogenous and endogenous biomolecules, with aldehydes emerging as a TRP channel trigger contributing to a cellular cascade that can lead to disease pathophysiology. The body is not only exposed to exogenous aldehydes via tobacco products or alcoholic beverages, but also to endogenous aldehydes triggered by lipid peroxidation. In response to lipid peroxidation from inflammation or organ injury, polyunsaturated fatty acids undergo lipid peroxidation to aldehydes, such as 4-hydroxynonenal. Reactive aldehydes activate TRP channels via aldehyde-induced protein adducts, leading to the release of pro-inflammatory mediators driving the pathophysiology caused by cellular injury, including inflammatory pain and organ reperfusion injury. Recent studies have outlined how aldehyde dehydrogenase 2 protects against aldehyde toxicity through the clearance of toxic aldehydes, indicating that targeting the endogenous aldehyde metabolism may represent a novel treatment strategy. An addition approach can involve targeting specific TRP channel regions to limit the triggering of a cellular cascade induced by aldehydes. In this review, we provide a comprehensive summary of aldehydes, TRP channels, and their interactions, as well as their role in pathological conditions and the different therapeutical treatment options.
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Mao, Qingqing, Jieyao Yuan, Lei Wang, Makayla Maher, and Chi Chen. "Novel Urinary Metabolites of Aldehydic Lipid Oxidation Products From Heated Soybean Oil Revealed by Aldehyde Abatement and Metabolomic Fingerprinting." Current Developments in Nutrition 6, Supplement_1 (June 2022): 310. http://dx.doi.org/10.1093/cdn/nzac053.051.
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Abstract Objectives Heated cooking oils are a constitutive component of contemporary human diets and a common ingredient in animal feed. Aldehydes, as the most reactive lipid oxidation products (LOPs) in heated oils, are widely considered as a contributor to the adverse health effect associated with heated oil consumption. Aldehydes-derived metabolites in biofluids are valuable for monitoring the exposure of the aldehydes from heated oils, but the efforts for their identification were hampered by the high reactivity of aldehydes as well as the chemical complexity caused by the coexistence of other LOPs in heated oils. To address this challenge, this study investigated the aldehydes-derived metabolites through the metabolomic fingerprinting of mouse urine samples from feeding heated oils with and without aldehyde abatement. Methods The heated soybean oil (HSO) was prepared by heating the control soybean oil (CSO) at 185°C for 6 h with constant air flow (50 ml/min). Both HSO and CSO were then mixed with the silica gel with piperazine side chain to remove their aldehyde content, producing the silica gel-treated HSO (HSO-si) and the silica gel-treated CSO (CSO-si), respectively. The urine, serum, fecal samples were collected from the C57BL/6 mice fed with 4 diets containing CSO, CSO-si, HSO, HSO-si, and then analyzed by the liquid chromatography-mass spectrometry (LC-MS) metabolomic analysis. Results The silica gel treatment dramatically reduced the aldehyde contents in HSO. Novel urinary metabolites formed by the reactions between 2,4-decadienal and lysine were identified through the metabolomic comparison between the HSO samples and the samples from 3 other treatment groups. Conclusions The identification of novel urinary metabolites of aldehydic LOPs warrants further biochemical examination on the chemical and metabolic processes responsible for their formation. These metabolites could become the biomarkers for monitoring the exposure of aldehydes in humans and animals. Funding Sources The research is partially supported by the NIFA project MIN-18–125.
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Nurbekova, Z. "Toxicity of reactive carbonyl compounds to plants." BULLETIN of the L.N. Gumilyov Eurasian National University. BIOSCIENCE Series 136, no. 3 (2021): 86–92. http://dx.doi.org/10.32523/2616-7034-2021-136-3-86-92.
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In plants, environmental stresses result in oxidative stress, lipid peroxidation and the generation of reactive carbonyl aldehydes. Reactive carbonyl aldehydes are downstream products of reactive oxygen species which can be described as critical cell-damaging agents in plants under various environmental stresses. In this paper toxicity of reactive carbonyl aldehydes and its generation under stress conditions are discussed. Moreover, involvement of reactive carbonyl aldehydes in stress- induced damage to plants is demonstrated. Toxic effect of reactive aldehydes such as acrolein, malondialdehyde and crotonaldehyde in plants under different stresses and their high electrophilicity is also discussed. Increases in malondialdehyde was demonstrated in UV-C stressed plants as the result of carbonyl modified proteins. A malondialdehyde is one of the widely shown aldehyde, which can be demonstrated as an indicator of reactive oxygen species. Malondialdehyde isomerized to 3-hydroxyacrolein whereas it can be described as a dialdehyde. The article considers detrimental actions of reactive carbonyl aldehydes and their chemical properties as well as detoxification of reactive carbonyl aldehydes by multiple enzymes such as aldehyde dehydrogenase, aldehyde reductase, aldo-keto reductase and 2-alkenal reductase.
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Nuñez, Alberto, Thomas A. Foglia, and George J. Piazza. "Cofactor recycling in a coupled enzyme oxidation–reduction reaction: conversion of ω‐oxo‐fatty acids into ω‐hydroxy and dicarboxylic acids." Biotechnology and Applied Biochemistry 29, no. 3 (June 1999): 207–12. http://dx.doi.org/10.1111/j.1470-8744.1999.tb00550.x.
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Aldehydes are reduced to alcohols by the enzyme alcohol dehydrogenase (ADH), whereas the enzyme aldehyde dehydrogenase (AldDH) oxidizes aldehydes to carboxylic acids. ADH and AldDH require, respectively, the reduced and oxidized forms of the cofactor NAD (NAD+/NADH). By combining both oxidation and reduction reactions into one process, it is possible to produce alcohols and carboxylic acids simultaneously from aldehydes by continuous recycling of the NAD+/NADH cofactor. However, both enzymes need to be active within the same pH region and buffer system. To test this hypothesis, the pH profile (Vmax and Vmax/Km) as well as the pKa of the prototropic groups involved in catalysis for both dehydrogenases were determined using (Z,Z)‐nona‐2,4‐dienal as a model substrate. The pH profile (Vmax and Vmax/Km) of both enzymes overlapped in the pH range of 6–8 in potassium phosphate buffer. When the coupled enzyme system was used at pH 7 with 10% NAD+ cofactor, over 90% of the starting aldehyde was converted to its corresponding acid and alcohol derivatives in a 1:1 ratio. The sequential action of the enzymes lipoxygenase and hydroperoxide lyase converts polyunsaturated fatty acids to aldehydic fatty acids. The products arising from the oxidation or reduction of the aldehydic functionality are of industrial interest. It was found that 13‐oxo‐9‐(Z),11‐(E)‐tridecadienoic acid, the product of the sequential reaction of soya bean lipoxygenase and hydroperoxide lyase from Chlorella pyrenoidosaon linoleic acid, is also a substrate in this coupled enzyme system.
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Mai, Juri, and Sascha Ott. "The Fascinating World of Phosphanylphosphonates: From Acetylenic Phosphaalkenes to Reductive Aldehyde Couplings." Synlett 30, no. 16 (August 13, 2019): 1867–85. http://dx.doi.org/10.1055/s-0039-1690129.
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This account highlights the versatility of phosphanylphosphonates, which can be used for the preparation of phosphorus-containing π-systems and as reagents for the reductive coupling of carbonyl compounds to alkenes. Phosphanylphosphonates with metal fragments coordinated to the P-lone pair have been known for a long time and they have been used for the synthesis of phosphaalkenes by means of the phospha-Horner–Wadsworth–Emmons reaction. With the original aim of incorporating phosphorus heteroatoms into classical all-carbon ethynylethene scaffolds, we entered the field of phosphanylphosphonates with the discovery that these compounds engage in complex cascade reactions with acetylenic ketones, forming 1,2-oxaphospholes, cumulenes, and bisphospholes. Later, we synthesized the first metal-free phosphanylphosphonate, which reacts with aldehydes to yield phosphaalkenes, but gives phospholones when diacetylenic ketones are used as substrates. In the final part of the account, we outline our discovery and the development of an unprecedented carbonyl–carbonyl cross-coupling reaction. This protocol offers a straightforward method for the synthesis of nonsymmetric 1,2-disubstituted alkenes directly from two dissimilar aldehydes.1 Combining Acetylenes with Phosphaalkenes2 Synthetic Examples of Acetylenic Phosphaalkenes3 The Phospha-Horner–Wadsworth–Emmons Approach to Phosphaalkenes3.1 Metal-Coordinated Phosphanylphosphonates3.2 Mechanism of the Phospha-Horner–Wadsworth–Emmons Reaction3.3 The First Metal-Free Phosphanylphosphonate and Its Reactivity with Aldehydes4 Reactions with Acetylenic Ketones4.1 Metal-Coordinated Phosphanylphosphonate and Monoacetylenic Ketones4.2 Metal-Coordinated Phosphanylphosphonate and Diacetylenic Ketones4.3 Metal-Free Phosphanylphosphonate and Diacetylenic Ketones5 Metal-Free Phosphanylphosphonate as a Coupling Reagent for Aldehydes6 E-Alkenes by the Reductive Coupling of Two Aldehydes7 Conclusions and Outlook
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Wang, Meng, Felix A. Dingler, and K. J. Patel. "Genotoxic aldehydes in the hematopoietic system." Blood 139, no. 14 (April 7, 2022): 2119–29. http://dx.doi.org/10.1182/blood.2019004316.
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Abstract Reactive aldehydes are potent genotoxins that threaten the integrity of hematopoietic stem cells and blood production. To protect against aldehydes, mammals have evolved a family of enzymes to detoxify aldehydes, and the Fanconi anemia DNA repair pathway to process aldehyde-induced DNA damage. Loss of either protection mechanisms in humans results in defective hematopoiesis and predisposition to leukemia. This review will focus on the impact of genotoxic aldehydes on hematopoiesis, the sources of endogenous aldehydes, and potential novel protective pathways.
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Gibson, Miles, Benita Claire Percival, Mark Edgar, and Martin Grootveld. "Low-Field Benchtop NMR Spectroscopy for Quantification of Aldehydic Lipid Oxidation Products in Culinary Oils during Shallow Frying Episodes." Foods 12, no. 6 (March 15, 2023): 1254. http://dx.doi.org/10.3390/foods12061254.
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Introduction: Toxic aldehydic lipid oxidation products (LOPs) arise from the thermo-oxidative deterioration of unsaturated fatty acids present in heated culinary oils when exposed to high-temperature frying episodes, and currently these effects represent a major public health concern. Objectives: In this study, we investigated the applications of low-field (LF), benchtop NMR analysis to detect and quantify toxic aldehyde species in culinary oils following their exposure to laboratory-simulated shallow frying episodes (LSSFEs) at 180 °C. Four culinary oils of variable fatty acid (FA) composition were investigated to determine the analytical capabilities of the LF NMR instrument. Oil samples were also analysed using a medium-field (400 MHz) NMR facility for comparative purposes. Results: Aldehydes were quantified as total saturated and total α,β-unsaturated classes. The time-dependent production of α,β-unsaturated aldehydes decreased in the order chia > rapeseed ≈ soybean > olive oils, as might be expected from their polyunsaturated and monounsaturated FA (PUFA and MUFA, respectively) contents. A similar but inequivalent trend was found for saturated aldehyde concentrations. These data strongly correlated with medium-field 1H NMR data obtained, although LF-determined levels were significantly lower in view of its inability to detect or quantify the more minor oxygenated aldehydic LOPs present. Lower limit of detection (LLOD) values for this spectrometer were 0.19 and 0.18 mmol/mol FA for n-hexanal and trans-2-octenal, respectively. Aldehydic lipid hydroperoxide precursors of aldehydic LOPs were also detectable in LF spectra. Conclusions: We therefore conclude that there is scope for application of these smaller, near-portable NMR facilities for commercial or ‘on-site’ quality control determination of toxic aldehydic LOPs in thermally stressed frying oils.
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Barua, Shawon, Siddharth Iyer, Avinash Kumar, Prasenjit Seal, and Matti Rissanen. "An aldehyde as a rapid source of secondary aerosol precursors: theoretical and experimental study of hexanal autoxidation." Atmospheric Chemistry and Physics 23, no. 18 (September 25, 2023): 10517–32. http://dx.doi.org/10.5194/acp-23-10517-2023.
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Abstract. Aldehydes are common constituents of natural and polluted atmospheres, and their gas-phase oxidation has recently been reported to yield highly oxygenated organic molecules (HOMs) that are key players in the formation of atmospheric aerosol. However, insights into the molecular-level mechanism of this oxidation reaction have been scarce. While OH initiated oxidation of small aldehydes, with two to five carbon atoms, under high-NOx conditions generally leads to fragmentation products, longer-chain aldehydes involving an initial non-aldehydic hydrogen abstraction can be a path to molecular functionalization and growth. In this work, we conduct a joint theoretical–experimental analysis of the autoxidation chain reaction of a common aldehyde, hexanal. We computationally study the initial steps of OH oxidation at the RHF-RCCSD(T)-F12a/VDZ-F12//ωB97X-D/aug-cc-pVTZ level and show that both aldehydic (on C1) and non-aldehydic (on C4) H-abstraction channels contribute to HOMs via autoxidation. The oxidation products predominantly form through the H abstraction from C1 and C4, followed by fast unimolecular 1,6 H-shifts with rate coefficients of 1.7×10-1 and 8.6×10-1 s−1, respectively. Experimental flow reactor measurements at variable reaction times show that hexanal oxidation products including HOM monomers up to C6H11O7 and accretion products C12H22O9−10 form within 3 s reaction time. Kinetic modeling simulations including atmospherically relevant precursor concentrations agree with the experimental results and the expected timescales. Finally, we estimate the hexanal HOM yields up to seven O atoms with mechanistic details through both C1 and C4 channels.
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Pikh, Zoryan. "Oxidation of unsaturated aldehydes by different oxidants." Chemistry & Chemical Technology 1, no. 2 (June 15, 2007): 61–69. http://dx.doi.org/10.23939/chcht01.02.061.
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The new data about oxidation of unsaturated aldehydes of a general structure R–CH = C(R)–CHO by molecular oxygen (in liquid and gaseous phase), peracids and hydrogen peroxide were obtained. The composition of reaction products for a series of aldehydes with different structures was determined. The dependencies of the selectivity of reaction from an aldehyde structure and oxidant type have been evaluated. It has been assumed that a stage of aldehyde interaction with peracid determines the formation of reaction products. The common mechanisms of unsaturated aldehydes oxidation by different oxidants have been established on the basis of generalization of obtained results.
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Ferreira, Patricia, Aitor Hernández-Ortega, Beatriz Herguedas, Jorge Rencoret, Ana Gutiérrez, María Jesús Martínez, Jesús Jiménez-Barbero, Milagros Medina, and Ángel T. Martínez. "Kinetic and chemical characterization of aldehyde oxidation by fungal aryl-alcohol oxidase." Biochemical Journal 425, no. 3 (January 15, 2010): 585–93. http://dx.doi.org/10.1042/bj20091499.
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Fungal AAO (aryl-alcohol oxidase) provides H2O2 for lignin biodegradation. AAO is active on benzyl alcohols that are oxidized to aldehydes. However, during oxidation of some alcohols, AAO forms more than a stoichiometric number of H2O2 molecules with respect to the amount of aldehyde detected due to a double reaction that involves aryl-aldehyde oxidase activity. The latter reaction was investigated using different benzylic aldehydes, whose oxidation to acids was demonstrated by GC-MS. The steady- and presteady state kinetic constants, together with the chromatographic results, revealed that the presence of substrate electron-withdrawing or electron-donating substituents had a strong influence on activity; the highest activity was with p-nitrobenzaldehyde and halogenated aldehydes and the lowest with methoxylated aldehydes. Moreover, activity was correlated to the aldehyde hydration rates estimated by 1H-NMR. These findings, together with the absence in the AAO active site of a residue able to drive oxidation via an aldehyde thiohemiacetal, suggested that oxidation mainly proceeds via the gem-diol species. The reaction mechanism (with a solvent isotope effect, 2H2Okred, of approx. 1.5) would be analogous to that described for alcohols, the reductive half-reaction involving concerted hydride transfer from the α-carbon and proton abstraction from one of the gem-diol hydroxy groups by a base. The existence of two steps of opposite polar requirements (hydration and hydride transfer) explains some aspects of aldehyde oxidation by AAO. Site-directed mutagenesis identified two histidine residues strongly involved in gem-diol oxidation and, unexpectedly, suggested that an active-site tyrosine residue could facilitate the oxidation of some aldehydes that show no detectable hydration. Double alcohol and aldehyde oxidase activities of AAO would contribute to H2O2 supply by the enzyme.
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Kitajima, Seiji, Yutaka Maruyama, and Motonaka Kuroda. "Volatile Short-Chain Aliphatic Aldehydes Act as Taste Modulators through the Orally Expressed Calcium-Sensing Receptor CaSR." Molecules 28, no. 12 (June 6, 2023): 4585. http://dx.doi.org/10.3390/molecules28124585.
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Aldehydes are natural volatile aroma compounds generated by the Maillard reaction of sugars and amino acids in food and affect the flavor of food. They have been reported to exert taste-modifying effects, such as increases in taste intensity at concentrations below the odor detection threshold. The present study examined the taste-enhancing effects of short-chain aliphatic aldehydes, such as isovaleraldehyde (IVAH) and 2-methylbutyraldehyde, thus attempting to identify the taste receptors involved. The results obtained revealed that IVAH enhanced the taste intensity of taste solutions even under the condition of olfactory deprivation by a noseclip. Furthermore, IVAH activated the calcium-sensing receptor CaSR in vitro. Receptor assays on aldehyde analogues showed that C3-C6 aliphatic aldehydes and methional, a C4 sulfur aldehyde, activated CaSR. These aldehydes functioned as a positive allosteric modulator for CaSR. The relationship between the activation of CaSR and taste-modifying effects was investigated by a sensory evaluation. Taste-modifying effects were found to be dependent on the activation state of CaSR. Collectively, these results suggest that short-chain aliphatic aldehydes function as taste modulators that modify sensations by activating orally expressed CaSR. We propose that volatile aroma aldehydes may also partially contribute to the taste-modifying effect via the same molecular mechanism as kokumi substances.
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Lin, Jiawei, Hecheng Meng, Xiaobing Guo, Zhongsheng Tang, and Shujuan Yu. "Natural Aldehyde-Chitosan Schiff Base: Fabrication, pH-Responsive Properties, and Vegetable Preservation." Foods 12, no. 15 (July 31, 2023): 2921. http://dx.doi.org/10.3390/foods12152921.
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The aim of the present work was to fabricate Schiff base compounds between chitosan and aldehydes and use the resultant aldehyde-chitosan Schiff bases for broccoli preservation. Using an element analyzer, the degree of substitution was calculated as 68.27–94.65%. The aldehyde-chitosan Schiff bases showed acidic sensitivity to rapid hydrolysis for releasing aldehyde at a buffer solution of pH 4–6, in which more than 39% of the aldehydes were released within 10 h. The release of aldehydes endows the aldehyde-chitosan Schiff bases with a better antibacterial activity at pH 5 than at pH 7. In a simulated CO2 (5–15%) atmosphere with high humidity (92%), the hydrolysis of imine bonds (C=N) was triggered and continuously released aldehyde, even without direct contact with the aqueous phase. The application of aldehyde-chitosan Schiff bases significantly extended the shelf life of broccoli from 4 d to 5–7 d and decreased the weight loss of broccoli during storage. In summary, the fabrication of aldehyde-chitosan Schiff bases and the strategy of using pH-response imine bond (C=N) hydrolysis (thus releasing aldehyde to kill microorganisms) were feasible for use in developing EO-incorporated intelligent food packages for vegetable preservation.
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Chaubey, Girija S., Simi Das, and Mahendra K. Mahanti. "Kinetics of oxidation of α,β-unsaturated aldehydes by quinolinium dichromate." Canadian Journal of Chemistry 81, no. 3 (March 1, 2003): 204–8. http://dx.doi.org/10.1139/v03-022.
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A series of α,β-unsaturated aldehydes (crotonaldehyde, cinnamaldehyde, acrylaldehyde, and methacrylaldehyde) were oxidized by quinolinium dichromate in sulfuric acid to the corresponding acids in 50% (v/v) acetic acid water medium. The kinetic data have been discussed with reference to the aldehyde hydration equilibria. The kinetic results support a mechanistic pathway proceeding via a rate-determining oxidative decomposition of the chromate ester of the aldehyde hydrate.Key words: kinetics, oxidation, unsaturated aldehydes, quinolinium dichromate.
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Spite, Matthew, Shahid P. Baba, Yonis Ahmed, Oleg A. Barski, Kanchan Nijhawan, J. Mark Petrash, Aruni Bhatnagar, and Sanjay Srivastava. "Substrate specificity and catalytic efficiency of aldo-keto reductases with phospholipid aldehydes." Biochemical Journal 405, no. 1 (June 13, 2007): 95–105. http://dx.doi.org/10.1042/bj20061743.
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Phospholipid oxidation generates several bioactive aldehydes that remain esterified to the glycerol backbone (‘core’ aldehydes). These aldehydes induce endothelial cells to produce monocyte chemotactic factors and enhance monocyte–endothelium adhesion. They also serve as ligands of scavenger receptors for the uptake of oxidized lipoproteins or apoptotic cells. The biochemical pathways involved in phospholipid aldehyde metabolism, however, remain largely unknown. In the present study, we have examined the efficacy of the three mammalian AKR (aldo-keto reductase) families in catalysing the reduction of phospholipid aldehydes. The model phospholipid aldehyde POVPC [1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine] was efficiently reduced by members of the AKR1, but not by the AKR6 or the ARK7 family. In the AKR1 family, POVPC reductase activity was limited to AKR1A and B. No significant activity was observed with AKR1C enzymes. Among the active proteins, human AR (aldose reductase) (AKR1B1) showed the highest catalytic activity. The catalytic efficiency of human small intestinal AR (AKR1B10) was comparable with the murine AKR1B proteins 1B3 and 1B8. Among the murine proteins AKR1A4 and AKR1B7 showed appreciably lower catalytic activity as compared with 1B3 and 1B8. The human AKRs, 1B1 and 1B10, and the murine proteins, 1B3 and 1B8, also reduced C-7 and C-9 sn-2 aldehydes as well as POVPE [1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphoethanolamine]. AKR1A4, B1, B7 and B8 catalysed the reduction of aldehydes generated in oxidized C16:0-20:4 phosphatidylcholine with acyl, plasmenyl or alkyl linkage at the sn-1 position or C16:0-20:4 phosphatidylglycerol or phosphatidic acid. AKR1B1 displayed the highest activity with phosphatidic acids; AKR1A4 was more efficient with long-chain aldehydes such as 5-hydroxy-8-oxo-6-octenoyl derivatives, whereas AKR1B8 preferred phosphatidylglycerol. These results suggest that proteins of the AKR1A and B families are efficient phospholipid aldehyde reductases, with non-overlapping substrate specificity, and may be involved in tissue-specific metabolism of endogenous or dietary phospholipid aldehydes.
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Cava, R., J. Ruiz, J. Ventanas, and T. Antequera. "Effect of α—tocopheryl acetate supplementation and the extensive feeding of pigs on the volatile aldehydes during the maturation of Iberian ham / Efecto del suplemento con acetato de α—tocoferol y de la alimentación en extensive del cerdo en los aldehídos volátiles durante la maduración del jamón Ibérico." Food Science and Technology International 5, no. 3 (June 1999): 235–41. http://dx.doi.org/10.1177/108201329900500306.
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The effect of feeding regime—free—range reared on acorn and pasture, or in confinement with and without the incorporation of 100 mg/kg α-tocopheryl acetate to pig mixed feeds—on volatile alde hyde content in Biceps femoris muscle throughout the ripening of Iberian ham was studied. Saturated aldehydes from 4 to 10 carbon chain and two diunsaturated aldehydes, 2,4-nonadienal and 2,4- decadienal, were found in ham samples. Volatile aldehyde evolution was not affected by feeding regime throughout ripening of hams. Volatile aldehyde content and individual aldehydes rose mark edly from Day 0 to Day 210 ( p < 0.05), and afterwards decreased to Day 700 ( p < 0.05). Both α- tocopheryl acetate supplementation and feeding on acorn and pasture significantly decreased the total and individual aldehydes in Biceps femoris samples at Days 0, 210 and 700 ( p < 0.05) in compari son with muscle samples from pigs fed the non-supplemented diet.
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Averill-Bates, Diana A., Enzo Agostinelli, Ewa Przybytkowski, and Bruno Mondovi. "Aldehyde dehydrogenase and cytotoxicity of purified bovine serum amine oxidase and spermine in Chinese hamster ovary cells." Biochemistry and Cell Biology 72, no. 1-2 (January 1, 1994): 36–42. http://dx.doi.org/10.1139/o94-006.
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Bovine serum amine oxidase (EC 1.4.3.6) catalyses the oxidative deamination of polyamines giving rise to the corresponding aldehydes, ammonia, and hydrogen peroxide. It has been suggested that the dialdehyde produced during the oxidation of spermine subsequently undergoes spontaneous β-elimination to form acrolein. Oxidation of the aldehydes by aldehyde dehydrogenase (EC 1.2.1.5) thus eliminates these reactive species and prevents the formation of acrolein. This work studies the role of each of the oxidation products of spermine in cytotoxicity induced by purified bovine serum amine oxidase. The inhibition patterns of NAD-dependent aldehyde dehydrogenase and catalase against cytotoxicity of bovine serum amine oxidase were determined in Chinese hamster ovary cells at 37 °C. Cytotoxicity caused by exogenous hydrogen peroxide, added directly (> 10 μM) or generated by glucose oxidase (0.5 U/mL), was completely inhibited by catalase. Cytotoxicity caused by bovine serum amine oxidase (5.7 × 10−3 U/mL) and spermine (340 μM) was completely inhibited by catalase only during short incubation times after which time cytotoxicity occurred. This indicates that hydrogen peroxide was the only species contributing to cytotoxicity at this stage of the reaction. Aldehyde dehydrogenase alone caused partial inhibition of cytotoxicity, but only later in the reaction. Cytotoxicity was completely eliminated in the presence of both catalase and aldehyde dehydrogenase. Exogenous acrolein (> 50 μM) also caused cytotoxicity in Chinese hamster ovary cells. However, hydrogen peroxide was toxic to cells at lower concentrations and at shorter exposure times relative to aldehydes. These data show that both peroxide and aldehydes contribute to cytotoxicity of oxidation products of spermine. Aldehydes such as acrolein are responsible for cytotoxicity that cannot be accounted for by hydrogen peroxide.Key words: acrolein, hydrogen peroxide, catalase, polyamine.
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Bercich, Mark D., Richard C. Cambie, and Peter S. Rutledge. "Experiments Directed Towards the Synthesis of Anthracyclinones. XXXII. Synthesis of Anthraquinone Aldehydes." Australian Journal of Chemistry 52, no. 4 (1999): 241. http://dx.doi.org/10.1071/c98102.
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Syntheses of C2 anthraquinone aldehydes from the commercially availableanthraru¯n (1) have been investigated. A synthesis of the keto aldehyde(2) in nine steps and 73% overall yield was achieved. Syntheses of (2)exploiting selective oxidations of either a C-boundallyl group by Wacker oxidation to introduce the methyl keto functionality orof a C-bound prop-1-enyl moiety by dihydroxylation andoxidative cleavage to generate the C2 formyl group were also developed. Thealdehyde (27) was synthesized in seven steps and in 81% overall yieldfrom (1), and syntheses of the phenolic aldehydes (33), (34), and (35), the C1benzyloxy aldehyde (36) and the anthracene aldehyde (37) were also developed.
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Liang, Xin, Ruyi Qian, Dan Wang, Lijuan Liu, Chengliang Sun, and Xianyong Lin. "Lipid-Derived Aldehydes: New Key Mediators of Plant Growth and Stress Responses." Biology 11, no. 11 (October 29, 2022): 1590. http://dx.doi.org/10.3390/biology11111590.
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Aldehydes, derivatives of lipids, are ubiquitously produced through non-enzymatic and enzymatic pathways in higher plants and participate in many physiological and biological processes. Increasing evidence demonstrates that aldehydes are involved in plants response to many abiotic stresses, such as light, drought, heat and nutrient deficiency. In plant cells, endogenously triggered or exogenously applied high concentrations of aldehydes can damage proteins and nucleic acid, disturb redox homeostasis, and consequently inhibit plant growth; therefore, they are considered cytotoxins. Aldehyde levels are also used as biomarkers to evaluate the health status of plants. Further genetic research shows that several enzymes have strong capacities to detoxify these electrophilic aldehydes. Small molecules, such as carnosine and glutathione, also exhibit the ability to scavenge aldehydes, effectively promoting plant growth. Recently, increasing evidence has shown that certain aldehydes at certain concentrations can upregulate survival genes, activate antioxidant responses, increase defense against pathogens and stimulate plant growth. This review summarizes recent studies of lipid-derived aldehydes in higher plants, mainly focusing on the generation pathway, toxic effects, and detoxification strategies. In addition, the signaling effects of aldehydes in plants are also discussed.
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Floss, Maximilian Alexander, Tobias Fink, Felix Maurer, Thomas Volk, Sascha Kreuer, and Lukas Martin Müller-Wirtz. "Exhaled Aldehydes as Biomarkers for Lung Diseases: A Narrative Review." Molecules 27, no. 16 (August 17, 2022): 5258. http://dx.doi.org/10.3390/molecules27165258.
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Breath analysis provides great potential as a fast and non-invasive diagnostic tool for several diseases. Straight-chain aliphatic aldehydes were repeatedly detected in the breath of patients suffering from lung diseases using a variety of methods, such as mass spectrometry, ion mobility spectrometry, or electro-chemical sensors. Several studies found increased concentrations of exhaled aldehydes in patients suffering from lung cancer, inflammatory and infectious lung diseases, and mechanical lung injury. This article reviews the origin of exhaled straight-chain aliphatic aldehydes, available detection methods, and studies that found increased aldehyde exhalation in lung diseases.
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Matsui, K., S. Kurishita, A. Hisamitsu, and T. Kajiwara. "A lipid-hydrolysing activity involved in hexenal formation." Biochemical Society Transactions 28, no. 6 (December 1, 2000): 857–60. http://dx.doi.org/10.1042/bst0280857.
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Short-chain aldehydes such as (3Z)-hexenal and n-hexanal are formed from lipids through sequential actions of lipid-hydrolysing, lipoxygenase and fatty acid hydroperoxide lyase activities. The aldehydes are formed upon wounding of plant tissues, and are reported to have bactericidal and fungicidal activities. Furthermore, it has been reported that the aldehydes can induce expression of a subset of genes involved in disease resistance and that they are involved in a defence response against insect herbivores. Although several genes encoding lipoxygenases and the lyases have been isolated, and characterized to some extent, only little is known about the enzyme accountable for the lipid-hydrolysing step. In this study, we tried to characterize the lipid-hydrolysing activity involved in the short-chain aldehyde formation in Arabidopsis. When Arabidopsis leaves were homogenized, (3Z)-hexenal was formed rapidly within a few minutes. During this time period, the amount of α-linolenic acid and C16:3 rapidly decreased. Such a rapid increase of the aldehyde was repressed almost completely when the leaves were homogenized under a nitrogen stream, and instead free trienoic acids accumulated. A lipase inhibitor, quinacrine, successfully repressed the hydrolysis. It was revealed that trienoic acids in monogalactosyldiacylglycerol were predominantly hydrolysed during the formation of short-chain aldehydes. Collectively, it is suggested that the lipolytic enzyme involved in the short-chain aldehyde formation is a galactolipid-specific lipase.
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Jockers, R., and R. D. Schmid. "Synthesis of Long-Chain Triazine Aldehydes - Substrates of Bacterial Luciferase and Photosynthetic Inhibitors." Zeitschrift für Naturforschung C 47, no. 7-8 (August 1, 1992): 573–79. http://dx.doi.org/10.1515/znc-1992-7-814.
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S-triazines are photosynthetic inhibitors. They have been substituted with ω-aminoundecanoic acid. The coupling products have been transformed into triazine aldehydes. These compounds displace radioactive terbutryn and have inhibitory effects on photosynthesis in plants and bacteria. Triazine aldehydes were shown to be effective substrates for bacterial luciferase. A competitive assay between photosystem-II-herbicides and aldehyde-labeled triazines is discussed.
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Czaplicka, Marianna, and Michał Chrobok. "Selected carbonyl compounds in the air of Silesia region." E3S Web of Conferences 28 (2018): 01006. http://dx.doi.org/10.1051/e3sconf/20182801006.
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This study was carried out to characterize three aldehydes of health concern (formaldehyde, acetaldehyde, and acrolein) at a three sites in Silesian region (Poland) in January and June 2015. Aldehydes in polluted atmospheres comes from both primary and secondary sources, which limits the control strategies for these reactive compounds. Average aldehyde concentration in summer period lies in range from 3.13 μg/m3 to 10.43 μg/m3, in winter period in range from 29.0 μg/m3 to 32.2 μg/m3. Acetaldehyde was dominant compound in winter period, in summer formaldehyde concentration was highest of all determined aldehydes.
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Monteiro, Júlia L., Natália M. Moreira, Deborah A. dos Santos, Márcio W. Paixão, and Arlene G. Corrêa. "Step economy strategy for the synthesis of amphoteric aminoaldehydes, key intermediates for reduced hydantoins." Pure and Applied Chemistry 90, no. 1 (January 26, 2018): 121–32. http://dx.doi.org/10.1515/pac-2017-0705.
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AbstractDespite of the orthogonal reactivity of the N–H aziridines aldehyde, these compounds exist as an equilibrium of three different forms – whereas the dimeric one is mostly observed in a variety of solvents. In this work, we have developed an alternative protocol for the aminoaldehyde dimers synthesis in two steps starting with an organocatalyzed aziridination between α,β-unsaturated aldehydes and a protected amine to afford known isolable and stable N-protected aziridine aldehydes. After Boc-deprotection, dimeric species were immediately formed from monomeric N–H aziridine aldehydes. From this building-block new reduced hydantoins were prepared via [3+2]-annulation with isocyanates.
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Kippo, Takashi, Yuki Kimura, Mitsuhiro Ueda, Takahide Fukuyama, and Ilhyong Ryu. "Bromine-Radical-Mediated Synthesis of β-Functionalized β,γ- and δ,ε-Unsaturated Ketones via C–H Functionalization of Aldehydes." Synlett 28, no. 14 (June 29, 2017): 1733–37. http://dx.doi.org/10.1055/s-0036-1588494.
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The bromine-radical-mediated allylation reaction of aldehydes was studied. In the presence of V-65 as radical initiator, the reaction of aldehydes with allyl bromides gave β,γ-unsaturated ketones in good yields (13 examples, 45–84%). The reaction is triggered by hydrogen abstraction from the aldehyde by bromine radical to form an acyl radical, which undergoes an SH2′-type addition–elimination reaction with allyl bromides to give coupling products with liberation of bromine radical. Three-component coupling reactions comprising aldehydes, electron-deficient alkenes, and methallyl bromide also proceeded to give δ,ε-unsaturated ketones.
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Yuan, Zeqin, Jun Liao, Hao Jiang, Peng Cao, and Yang Li. "Aldehyde catalysis – from simple aldehydes to artificial enzymes." RSC Advances 10, no. 58 (2020): 35433–48. http://dx.doi.org/10.1039/d0ra06651f.
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Gryko, Daniel T., and Katarzyna E. Piechota. "Straightforward route to trans-A2B-corroles bearing substituents with basic nitrogen atoms." Journal of Porphyrins and Phthalocyanines 06, no. 02 (February 2002): 81–97. http://dx.doi.org/10.1142/s1088424602000129.
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We have developed a comprehensive methodology that affords regioisomerically pure trans- A 2 B -corroles bearing substituents with basic nitrogen atoms at meso positions. The corrole formation reaction involves the acid-catalyzed condensation of a dipyrromethane (DPM) and an aldehyde followed by oxidation with DDQ. The optimal conditions for this process were identified by extensive modifications of the previously developed conditions for the synthesis of trans-A2B-corroles with aromatic substituents. In particular three distinct sets of conditions were identified for various specific cases. Pyridine, quinoline and quinoxaline derived aldehydes as well as other aromatic aldehydes with tertiary amine groups in different positions were succesfully used in the condensation involving sterically hindered dipyrromethanes under the following conditions: (First step: CH 2 Cl 2, [DPM] = 33 mM, [aldehyde] = 17 mM, [TFA] = 50 mM, 1h, room temperature, second step: neutralization with Et 3 N , CH 2 Cl 2, dilution 26 times, 1.5 or 1.3 eqs. of DDQ versus DPM). A different set of conditions was developed for the condesation involving sterically unhindered dipyrromethanes: (first step: CH 2 Cl 2, [DPM] = 33 mM, [aldehyde] = 17 mM, [TFA] = 17 mM, 5h, room temperature, second step: neutralization with Et 3 N , CH 2 Cl 2, dilution 26 times, 1 eq of DDQ versus DPM). In this case only aldehydes with the formyl group directly adjacent to the heterocylic ring are efficient substrates; for the remaining aldehydes an extensive scrambling was observed. The condensation of pyridyldipyrromethanes with aldehydes bearing electron-withdrawing substituents (first step: CH 2 Cl 2, [DPM] = 33 mM, [aldehyde] = 17 mM, [TFA] = 67 mM, 1h, room temperature, second step: neutralization with Et 3 N , CH 2 Cl 2, dilution 26 times, 1 eq of DDQ versus DPM) leads to corroles in 2-11 % yield depending on the position of the nitrogen atom. Finally, 10-(4-formylphenyl)-5,15-dimesitylcorrole was obtained and reacted with mesityldipyrromethane, giving the symmetrical corrole dyad in 14% yield. A total of 21 new corroles of type trans- A 2 B were prepared.
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Lodge, J. K., S. U. Patel, and P. J. Sadler. "Aldehydes from metal ion- and lipoxygenase-induced lipid peroxidation: detection by 1H-n.m.r. spectroscopy." Biochemical Journal 289, no. 1 (January 1, 1993): 149–53. http://dx.doi.org/10.1042/bj2890149.
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The modification of lipoproteins by reactive aldehydes formed via lipid peroxidation is thought to be a key process in the pathogenesis of atherosclerosis. We show that 1H-n.m.r. spectroscopy can readily be used to detect a variety of different aldehydes resulting from peroxidation of liposomes induced by Fenton's reagent or lipoxygenase, and aldehydes arising from copper-induced reactions of low-density lipoprotein. There is a clear contrast between the major aldehydic products arising from metal-ion- and lipoxygenase-induced reactions.
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Roffman, E., and M. Wilchek. "The extent of oxidative mitogenesis does not correlate with the degree of aldehyde formation of the T lymphocyte membrane." Journal of Immunology 137, no. 1 (July 1, 1986): 40–44. http://dx.doi.org/10.4049/jimmunol.137.1.40.
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Abstract Chemical oxidation of T lymphocytes with periodate or the combined action of the enzymes neuraminidase and galactose oxidase (NAGO) results in T cell activation. The latter process includes the production of interleukin 2 (IL 2) and the induction of IL 2 receptors. Because membrane-bound aldehydes act in the transmission of the oxidative mitogenic signal, we designed a comparative study in human thymocytes and peripheral blood leukocytes in order to determine a possible correlation between the degree of the membrane aldehydes generated chemically or enzymatically and the extent of the resulting activation. The differences between periodate- and NAGO-induced aldehydes were demonstrated by flow cytometry of cells stained with a novel fluoresceinated hydrazide and by an electrophoretic procedure performed with biocytin hydrazide and 125I-streptavidin. In both cellular systems, periodate oxidation resulted in stronger formation of aldehydes than NAGO oxidation. However, the IL 2 receptor induced by NAGO formation and the resultant activation were significantly higher than those induced by periodate. The degree of aldehyde formation on peripheral blood leukocytes was also considerably higher than that of thymocytes, yet similar patterns of [3H]thymidine uptake were observed in the mitogenic assays of both cellular systems. The data indicate that no correlation exists between the extent of aldehyde formation and the degree of oxidative mitogenesis. It is thus suggested that relatively few (or maybe only one) membrane-bound aldehyde-containing molecules act in the transmission of the oxidative mitogenic signal.
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Seebacher, Werner, Michael Hoffelner, Ferdinand Belaj, Teresa Pirker, Muaaz Alajlani, Rudolf Bauer, Eva-Maria Pferschy-Wenzig, Robert Saf, and Robert Weis. "Formation of 5-Aminomethyl-2,3-dihydropyridine-4(1H)-ones from 4-Amino-tetrahydropyridinylidene Salts." Molecules 28, no. 19 (September 29, 2023): 6869. http://dx.doi.org/10.3390/molecules28196869.
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Various 4-aminotetrahydropyridinylidene salts were treated with aldehydes in an alkaline medium. Their conversion to 5-substituted β-hydroxyketones in a one-step reaction succeeded only with an aliphatic aldehyde. Instead, aromatic aldehydes gave 5-substituted β-aminoketones or a single δ-diketone. The new compounds were characterized using spectroscopic methods and a single crystal structure analysis. Some of them showed anticancer and antibacterial properties.
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Dehoux-Zenou, S. M., M. Guenounou, H. Zinbi, P. Ougen, R. Couderc, and J. C. Agneray. "Behavior of aldehyde moieties involved in the activation of suppressor cells by sodium periodate." Journal of Immunology 138, no. 4 (February 15, 1987): 1157–63. http://dx.doi.org/10.4049/jimmunol.138.4.1157.
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Abstract The treatment of mouse spleen cells with periodate at the optimal mitogenic concentration (1 mM) induces the activation of suppressor cells of the in vitro antibody response and leads to the formation of aldehydes on the carbohydrate termini of the surface sialoglycoconjugates. These aldehyde moieties are found on the C8 (N-AN 8) and the C7 (N-AN 7) derivatives of sialic acid. Immediate borohydride reduction prevents the activation of the suppressor cells. Data from this work show that borohydride reduction must be performed within the first 6 hr to prevent the generation of suppressor cells; 18 hr after the initial periodate oxidation, borohydride treatment did not reverse the in vitro suppressive activity of periodate-treated cells. The kinetics of the disappearance of aldehydes from the cell surface were studied by using [3H]borohydride labeling and chromatographic analysis of sialic acid derivatives. About 70 to 80% of the aldehyde moieties were found to be present 6 hr after periodate oxidation. After 18 hr, 50 to 70% of the aldehyde had disappeared from the lymphocyte membrane. Oxidized sialyl residues disappear completely after 60 hr of culture. This period corresponds to the de novo synthesis of sialic acid residues on the surface of periodate-activated cells. The two classes of oxidized sialyl-glycoconjugates were found to behave in different ways. In effect, our data showed that the aldehydes remaining at 18 hr are mainly located on the gangliosides, whereas the aldehyde moieties located on high m.w. glycoproteins disappear from the cell surface between 9 and 18 hr. This would suggest that the remaining aldehydes located on gangliosides are not directly involved in the expression of suppressive activity.
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WINBERG, Jan-Olof, and John S. McKINLEY-McKEE. "Drosophila melanogaster alcohol dehydrogenase: mechanism of aldehyde oxidation and dismutation." Biochemical Journal 329, no. 3 (February 1, 1998): 561–70. http://dx.doi.org/10.1042/bj3290561.
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Drosophila alcohol dehydrogenase (Adh) catalyses the oxidation of both alcohols and aldehydes. In the latter case, the oxidation is followed by a reduction of the aldehyde, i.e. a dismutation reaction. At high pH, dismutation is accompanied by a small release of NADH, which is not observed at neutral pH. Previously it has been emphasized that kinetic coefficients obtained by measuring the increase in A340, i.e. the release of NADH at high pH is not a direct measure of the aldehyde oxidation reaction and these values cannot be compared with those for alcohol dehydrogenation. In this article we demonstrate that this is not entirely true, and that the coefficients ϕB and ϕAB, where B is the aldehyde and A is NAD+, are the same for a dismutation reaction and a simple aldehyde dehydrogenase reaction. Thus the substrate specificity of the aldehyde oxidation reaction can be determined by simply measuring the NADH release. The coefficients for oxidation and dehydrogenation reactions (ɸ0d and ϕAd respectively) are complex and involve the constants for the dismutation reaction. However, dead-end inhibitors can be used to determine the quantitative contribution of the kinetic constants for the aldehyde oxidation and reduction pathways to the ϕ0d and ϕAd coefficients. The combination of dead-end and product inhibitors can be used to determine the reaction mechanism for the aldehyde oxidation pathway. Previously, we showed that with Drosophila Adh, the interconversion between alcohols and aldehydes followed a strictly compulsory ordered pathway, although aldehydes and ketones formed binary complexes with the enzyme. This raised the question regarding the reaction mechanism for the oxidation of aldehydes, i.e. whether a random ordered pathway was followed. In the present work, the mechanism for the oxidation of different aldehydes and the accompanying dismutation reaction with the slow alleloenzyme (AdhS) from Drosophila melanogaster has been studied. To obtain reliable results for the liberation of NADH during the initial-rate phase, the reaction was measured with a sensitive recording filter fluorimeter, and the complexes formed with the different dead-end and product inhibitors have been interpreted on the basis of a full dismutation reaction. The results are only consistent with a compulsory ordered reaction mechanism, with the formation of a dead-end binary enzyme-aldehyde complex. Under initial-velocity conditions, the rate of acetate release was calculated to be larger than 2.5 s-1, which is more than ten times that of NADH. The substrate specificity constant (kcat/Km or 1/ϕB) with respect to the oxidation of substrates was propan-2-ol > ethanol > acetaldehyde > trimethylacetaldehyde.
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Sutaria, Saurin R., Sadakatali S. Gori, James D. Morris, Zhenzhen Xie, Xiao-An Fu, and Michael H. Nantz. "Lipid Peroxidation Produces a Diverse Mixture of Saturated and Unsaturated Aldehydes in Exhaled Breath That Can Serve as Biomarkers of Lung Cancer—A Review." Metabolites 12, no. 6 (June 18, 2022): 561. http://dx.doi.org/10.3390/metabo12060561.
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The peroxidation of unsaturated fatty acids is a widely recognized metabolic process that creates a complex mixture of volatile organic compounds including aldehydes. Elevated levels of reactive oxygen species in cancer cells promote random lipid peroxidation, which leads to a variety of aldehydes. In the case of lung cancer, many of these volatile aldehydes are exhaled and are of interest as potential markers of the disease. Relevant studies reporting aldehydes in the exhaled breath of lung cancer patients were collected for this review by searching the PubMed and SciFindern databases until 25 May 2022. Information on breath test results, including the biomarker collection, preconcentration, and quantification methods, was extracted and tabulated. Overall, 44 studies were included spanning a period of 34 years. The data show that, as a class, aldehydes are significantly elevated in the breath of lung cancer patients at all stages of the disease relative to healthy control subjects. The type of aldehyde detected and/or deemed to be a biomarker is highly dependent on the method of exhaled breath sampling and analysis. Unsaturated aldehydes, detected primarily when derivatized during preconcentration, are underrepresented as biomarkers given that they are also likely products of lipid peroxidation. Pentanal, hexanal, and heptanal were the most reported aldehydes in studies of exhaled breath from lung cancer patients.
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Knaus, Tanja, Vasilis Tseliou, Luke D. Humphreys, Nigel S. Scrutton, and Francesco G. Mutti. "A biocatalytic method for the chemoselective aerobic oxidation of aldehydes to carboxylic acids." Green Chemistry 20, no. 17 (2018): 3931–43. http://dx.doi.org/10.1039/c8gc01381k.
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Kabalka, George W., Su Yu, and Nan-Sheng Li. "Selective hydroboration of alkenes and alkynes in the presence of aldehydes and ketones." Canadian Journal of Chemistry 76, no. 6 (June 1, 1998): 800–805. http://dx.doi.org/10.1139/v98-042.
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The reactions of terminal alkenes in the presence of ketones or aldehydes with a variety of borane reagents have been investigated. It was found that the selective hydroboration of a terminal alkene in the presence of a ketone or an aldehyde is most efficient when dicyclohexylborane is used as the hydroborating agent. The hydroboration of olefinic ketones and olefinic aldehydes with dicyclohexylborane generates the corresponding hydroxyaldehydes and hydroxyketones in good yields after oxidation with sodium perborate. The hydroboration of alkynyl ketones and alkynyl aldehydes with dicyclohexylborane yields the corresponding olefinic carbonyl compounds after protonation, or dicarbonyl compounds after oxidation.Key words: hydroboration, reduction, dicyclohexylborane, hydroxyaldehyde, hydroxyketone.
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McClelland, Robert A., Pratima Sukhai, Karen M. Engell, and Poul E. Sorensen. "Hydration equilibria of 9-acridinecarboxaldehyde." Canadian Journal of Chemistry 72, no. 11 (November 1, 1994): 2333–38. http://dx.doi.org/10.1139/v94-297.
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Hydration rate constants and equilibrium constants have been obtained for 9-acridinecarboxaldehyde in aqueous solution. Under acidic conditions where the acridine is protonated, signals for the hydrate and free aldehyde forms can be observed as separate species in the 1H NMR spectrum. Integration provides the hydration equilibrium constant[Formula: see text] Using an apparent acidity constant obtained from a spectroscopic titration curve, the rate–pH profile was fitted to provide the hydration constant for the equilibration of the neutral acridines, KH = 0.07. This analysis also provides the acidity constants for the two acridinium ions, the aldehyde with pK = 3.78 and the hydrate with pK = 5.36. A comparison with the 4-pyridinecarboxaldehdye system reveals that the [Formula: see text] ratios for the acridine and pyridine are the same within experimental error, but that the acridine and acridinium aldehydes are 20-fold less hydrated than their pyridine analogs. A comparison with benzaldehydes reveals that, in their reactivities, the two heterocyclic aldehydes behave in a similar manner. Thus, for example, plots of log kH for the acid-catalyzed dehydration and hydrations versus log Kh for the equilibrium hydration show single correlation lines including the points for the benzaldehydes and heterocyclic aldehydes (but not the aliphatic aldehydes).
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Suzuki, Natsuhei, Daito Suda, Nguyen Thi Thuy Ngan, Namiko Gibu, Nguyen Lan Huong, To Kim Anh, and Daisuke Kasai. "Characterization of Latex-Clearing Protein and Aldehyde Dehydrogenases Involved in the Utilization of poly(cis-1,4-isoprene) by Nocardia farcinica NBRC 15532." Microorganisms 10, no. 12 (November 24, 2022): 2324. http://dx.doi.org/10.3390/microorganisms10122324.
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Microbial degradation of natural rubber and synthetic poly(cis-1,4-isoprene) is expected to become an alternative treatment system for waste from poly(cis-1,4-isoprene) products including scrap tires. Nocardia farcinica NBRC 15,532, a gram-positive rubber-degrading bacterium, can utilize poly(cis-1,4-isoprene) as the sole source of carbon and energy to produce oligo-isoprene metabolites containing aldehyde and keto end groups. A homology-based search of the genome revealed a gene encoding a latex-clearing protein (Lcp). Gene disruption analysis indicated that this gene is essential for the utilization of poly(cis-1,4-isoprene) in this strain. Further analysis of the genome sequence identified aldehyde dehydrogenase (ALDH) genes as potential candidates for oxidative degradation of oligo-isoprene aldehydes. Based on the enzymatic activity of the ALDH candidates, NF2_RS14000 and NF2_RS14385 may be involved in the degradation of oligo-isoprene aldehydes. Analysis of the reaction products revealed that these ALDHs oxidized tri- to penta-isoprene aldehydes, which were generated by the reaction of Lcp. Based on the inability of ALDH gene deletion mutants, we concluded that NF2_RS14000 is mainly involved in the utilization of poly(cis-1,4-isoprene) and the oxidative degradation of oligo-isoprene aldehydes in Nocardia farcinica NBRC 15,532.
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Kawajiri, Takahiro, Reiya Ohta, Hiromichi Fujioka, Hironao Sajiki, and Yoshinari Sawama. "Aromatic aldehyde-selective aldol addition with aldehyde-derived silyl enol ethers." Chemical Communications 54, no. 4 (2018): 374–77. http://dx.doi.org/10.1039/c7cc08936h.
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Evans, Amanda M., and Amy L. Stuart. "A Passive Sampling Study of Small-Scale Variations in Ambient Acetaldehyde and Formaldehyde Concentrations." Air, Soil and Water Research 4 (January 2011): ASWR.S7582. http://dx.doi.org/10.4137/aswr.s7582.
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Radiello passive diffusive aldehyde samplers were used to measure ambient formaldehyde and acetaldehyde levels, approximately every 0.7 km in a 10 km2 sampling area in Hillsborough County, Florida from January 21 to 28, 2010. Samples were analyzed for aldehyde-DNPH derivatives via high performance liquid chromatography with ultraviolet detection. Concentrations were compared with values at a regulatory fixed-site monitor. Distribution statistics, concentration ratios, and spatial contours were calculated to investigate spatial variability. Mean aldehyde concentrations were 2.4 and 1.1 μg/m3 for formaldehyde and acetaldehyde, respectively. Observed spatial concentration patterns were similar for both aldehydes and suggest the influence of nearby roadway emissions. Overall, the spatial variation was small, with coefficients of variation of 13% and 22%, respectively. Results here provide methods and data for understanding exposures to aldehydes at high spatial resolution.
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Sawama, Yoshinari, Yuya Miki, and Hironao Sajiki. "N-Heterocyclic Carbene Catalyzed Deuteration of Aldehydes in D2O." Synlett 31, no. 07 (March 3, 2020): 699–702. http://dx.doi.org/10.1055/s-0040-1707993.
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An N-heterocyclic carbene (NHC)-catalyzed direct deuteration of aldehydes in a mixed solvent of deuterium oxide (D2O) and cyclopentyl methyl ether was established. The present deuteration is possibly initiated by the formation of a Breslow intermediate from the aldehyde and the NHC, with subsequent trapping by D2O providing the monodeuterated aldehyde.
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Finkelstein, Erik I., Jurjen Ruben, C. Wendy Koot, Milena Hristova, and Albert van der Vliet. "Regulation of constitutive neutrophil apoptosis by the α,β-unsaturated aldehydes acrolein and 4-hydroxynonenal." American Journal of Physiology-Lung Cellular and Molecular Physiology 289, no. 6 (December 2005): L1019—L1028. http://dx.doi.org/10.1152/ajplung.00227.2005.
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Reactive α,β-unsaturated aldehydes are major components of common environmental pollutants and are products of lipid oxidation. Although these aldehydes have been demonstrated to induce apoptotic cell death in various cell types, we recently observed that the α,β-unsaturated aldehyde acrolein (ACR) can inhibit constitutive apoptosis of polymorphonuclear neutrophils and thus potentially contribute to chronic inflammation. The present study was designed to investigate the biochemical mechanisms by which two representative α,β-unsaturated aldehydes, ACR and 4-hydroxynonenal (HNE), regulate neutrophil apoptosis. Whereas low concentrations of either aldehyde (<10 μM) mildly promoted apoptosis in neutrophils (reflected by increased phosphatidylserine exposure, caspase-3 activation, and mitochondrial cytochrome c release), higher concentrations prevented critical features of apoptosis (caspase-3 activation, phosphatidylserine exposure) and caused delayed neutrophil cell death with characteristics of necrosis/oncosis. Inhibition of caspase-3 activation by either aldehyde occurred despite increases in mitochondrial cytochrome c release and occurred in close association with depletion of cellular GSH and with cysteine modifications within caspase-3. However, procaspase-3 processing was also prevented, because of inhibited activation of caspases-9 and -8 under similar conditions, suggesting that ACR (and to a lesser extent HNE) can inhibit both intrinsic (mitochondria dependent) and extrinsic mechanisms of neutrophil apoptosis at initial stages. Collectively, our results indicate that α,β-unsaturated aldehydes can inhibit constitutive neutrophil apoptosis by common mechanisms, involving changes in cellular GSH status resulting in reduced activation of initiator caspases as well as inactivation of caspase-3 by modification of its critical cysteine residue.
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Marrufo-Curtido, Almudena, Arancha de-la-Fuente-Blanco, María-Pilar Sáenz-Navajas, Vicente Ferreira, Mónica Bueno, and Ana Escudero. "Sensory Relevance of Strecker Aldehydes in Wines. Preliminary Studies of Its Removal with Different Type of Resins." Foods 10, no. 8 (July 23, 2021): 1711. http://dx.doi.org/10.3390/foods10081711.
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The orthonasal quality of two synthetic contexts of wine (young wine and oaked wine) spiked with six different levels of the Strecker aldehydes (isobutyraldehyde, 2-methylbutanal, 3-methylbutanal, methional and phenylacetaldehyde) was evaluated by a panel of wine experts. The aldehyde levels simulated the concentrations present in wines protected from oxidation during production and storage and after severe oxidation. Significant quality detriments were observed at concentrations of 13 µg/L of methional, 49 µg/L of phenylacetaldehyde, 17 µg/L of isobutyraldehyde, 12 µg/L of 2-methylbutanal and 24 µg/L of 3-methylbutanal. The presence of these levels of aldehyde concentrations induced the reduction of fruitiness in young wines and of woody notes in oaked wines as well as the appearance of the typical attributes that define wine oxidation. More than 75% of recently opened commercial wines contain total levels of Strecker aldehydes higher than those, however their effect is not always noticeable as they are forming inodorous adducts with SO2. Nevertheless, this content is a potential risk for the shelf life of the wine, as once SO2 is depleted, these aldehydes could release back into their odour-active forms. Thus, in order to reduce the presence of Strecker aldehydes, eight different resins were studied (two scavengers, four mixed-mode anion exchange and two pure anion exchange) in white wine at two levels of SO2. After 24-h contact, the mixed mode Strata X-A resin was able to significantly reduce aldehydes’ percentages: between 11% for isobutyraldehyde and 86% for phenylacetaldehyde. On the other hand, wine colour was affected and therefore the applicability of the treatment should be further studied. However, this work can be considered a starting point to solve the technological challenge involved in the elimination of aldehydes from wine.
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Wann, Angela I., Benita C. Percival, Katy Woodason, Miles Gibson, Siâny Vincent, and Martin Grootveld. "Comparative 1H NMR-Based Chemometric Evaluations of the Time-Dependent Generation of Aldehydic Lipid Oxidation Products in Culinary Oils Exposed to Laboratory-Simulated Shallow Frying Episodes: Differential Patterns Observed for Omega-3 Fatty Acid-Containing Soybean Oils." Foods 10, no. 10 (October 17, 2021): 2481. http://dx.doi.org/10.3390/foods10102481.
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Soybean oil is the second most exported oil from the United States and South America, and is widely marketed as a cooking oil product containing numerous health benefits for human consumers. However, culinary oils with high polyunsaturated fatty acid (PUFA) contents, are known to produce high quantities of lipid oxidation products (LOPs), including toxic aldehydes upon exposure to high-temperature frying episodes. Previous studies have demonstrated causal links between aldehyde ingestion and inhalation with deleterious health perturbations, including mutagenic and carcinogenic effects, along with cardiovascular and teratogenic actions. In this study, aldehydic LOPs were detected and quantified in commercially available samples of soybean, avocado, corn and extra-virgin olive oil products before and after their exposure to laboratory-simulated laboratory frying episodes (LSSFEs) using high-resolution 1H nuclear magnetic resonance (NMR) analysis. Results acquired demonstrated that PUFA-rich soybean and corn oils gave rise to the highest concentrations of oil aldehydes from the thermo-oxidation of unsaturated fatty acids, whereas monounsaturated fatty acid (MUFA)-laden avocado and olive oils were much more resistant to this peroxidation process, as expected. Multivariate chemometrics analyses provided evidence that an orthogonal component pattern of aldehydic LOPs featuring low-molecular-mass n-alkanals such as propanal, and 4-oxo-alkanals, arises from thermo-oxidation of the ω-3 fatty acid (FA) linolenic acid (present in soybean oils at levels of ca. 7% (w/w)), was able to at least partially distinguish this oil from corresponding samples of thermally-stressed corn oil. Despite having a similar total PUFA level, corn oil has only a negligible ω-3 FA content, and therefore generated significantly lower levels of these two aldehyde classes. In view of the adverse health effects associated with dietary LOP ingestion, alternative methodologies for the incorporation of soybean oils within high-temperature frying practices are proposed.
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Zeng, Lidan, Xuesong Li, Christopher B. Preusch, Gary J. He, Ningyi Xu, Tom H. Cheung, Jianan Qu, and Ho Yi Mak. "Nuclear receptors NHR-49 and NHR-79 promote peroxisome proliferation to compensate for aldehyde dehydrogenase deficiency in C. elegans." PLOS Genetics 17, no. 7 (July 8, 2021): e1009635. http://dx.doi.org/10.1371/journal.pgen.1009635.
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The intracellular level of fatty aldehydes is tightly regulated by aldehyde dehydrogenases to minimize the formation of toxic lipid and protein adducts. Importantly, the dysregulation of aldehyde dehydrogenases has been implicated in neurologic disorder and cancer in humans. However, cellular responses to unresolved, elevated fatty aldehyde levels are poorly understood. Here, we report that ALH-4 is a C. elegans aldehyde dehydrogenase that specifically associates with the endoplasmic reticulum, mitochondria and peroxisomes. Based on lipidomic and imaging analysis, we show that the loss of ALH-4 increases fatty aldehyde levels and reduces fat storage. ALH-4 deficiency in the intestine, cell-nonautonomously induces NHR-49/NHR-79-dependent hypodermal peroxisome proliferation. This is accompanied by the upregulation of catalases and fatty acid catabolic enzymes, as indicated by RNA sequencing. Such a response is required to counteract ALH-4 deficiency since alh-4; nhr-49 double mutant animals are sterile. Our work reveals unexpected inter-tissue communication of fatty aldehyde levels and suggests pharmacological modulation of peroxisome proliferation as a therapeutic strategy to tackle pathology related to excess fatty aldehydes.
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Chevolleau, Sylvie, Maria-Helena Noguer-Meireles, Loïc Mervant, Jean-François Martin, Isabelle Jouanin, Fabrice Pierre, Nathalie Naud, Françoise Guéraud, and Laurent Debrauwer. "Towards Aldehydomics: Untargeted Trapping and Analysis of Reactive Diet-Related Carbonyl Compounds Formed in the Intestinal Lumen." Antioxidants 10, no. 8 (August 6, 2021): 1261. http://dx.doi.org/10.3390/antiox10081261.
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Lipid peroxidation and subsequent formation of toxic aldehydes, such as 4-hydroxynonenal, is known to be involved in numerous pathophysiological processes, possibly including the development of colorectal cancer. This work aimed at the development of an untargeted approach using high-performance liquid chromatography coupled with high-resolution mass spectrometry (HPLC–HRMS) for tracking aldehydes in both suspect screening and untargeted methods in fecal water, representing the aqueous environment of colon epithelial cells. This original approach is based on the introduction of a characteristic isotopic labeling by selective derivatization of the carbonyl function using a brominated reagent. Following a metabolomics workflow, the developed methodology was applied to the characterization of aldehyde compounds formed by lipid peroxidation in rats fed two different diets differentially prone to lipoperoxidation. Derivatized aldehydes were first selectively detected on the basis of their isotopic pattern, then annotated and finally identified by tandem mass spectrometry. This original approach allowed us to evidence the occurrence of expected aldehydes according to their fatty acid precursors in the diet, and to characterize other aldehydes differentiating the different diets.
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Beckers, Sebastian J., Sam Parkinson, Elizabeth Wheeldon, and David K. Smith. "In situ aldehyde-modification of self-assembled acyl hydrazide hydrogels and dynamic component selection from complex aldehyde mixtures." Chemical Communications 55, no. 13 (2019): 1947–50. http://dx.doi.org/10.1039/c8cc09395d.
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Kumar, Vikas, and Stephen J. Connon. "Direct, efficient NHC-catalysed aldehyde oxidative amidation: in situ formed benzils as unconventional acylating agents." Chemical Communications 53, no. 73 (2017): 10212–15. http://dx.doi.org/10.1039/c7cc05561g.
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Makowski, Mathias, Martin Ohlmeyer, and Dietrich Meier. "Long-term development of VOC emissions from OSB after hot-pressing." Holzforschung 59, no. 5 (September 1, 2005): 519–23. http://dx.doi.org/10.1515/hf.2005.086.
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Abstract An oriented strand board (OSB) made of Scots pine (Pinus sylvestris L.) was tested for volatile organic compound (VOC) emissions 24 h after the hot-pressing process over a period of 2 months. The predominant emissions from the OSB were monoterpenes and aldehydes. Terpene emissions decreased continuously, whereas aldehyde concentrations initially increased and subsequently decayed. Aldehydes are formed by the autoxidative splitting of unsaturated fatty acids contained in the wood. Due to the delayed release of aldehydes, a comparison of different emission test results is only possible if age and storage conditions are clearly specified. For a reduction in VOC emissions from wood-based materials, wood properties, manufacturing process, and storage conditions have to be considered.
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Palágyi, Attila, Jindřich Jindřich, Juraj Dian, and Sophie Fourmentin. "Cyclodextrin-based Schiff base pro-fragrances: Synthesis and release studies." Beilstein Journal of Organic Chemistry 18 (September 28, 2022): 1346–54. http://dx.doi.org/10.3762/bjoc.18.140.
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A simple method for the preparation of β-cyclodextrin derivatives containing covalently bonded aldehydes via an imine bond was developed and used to prepare a series of derivatives from 6I-amino-6I-deoxy-β-cyclodextrin and the following volatile aldehydes – cinnamaldehyde, cyclamen aldehyde, lilial, benzaldehyde, anisaldehyde, vanillin, hexanal, heptanal, citral, and 5-methylfurfural. Subsequently, the rate of release of the volatile compound from selected pro-fragrances, as a function of the environment (solvent, pH), was studied by 1H NMR spectroscopy (for benzaldehyde) and static headspace-gas chromatography (for benzaldehyde, heptanal, and 5-methylfurfural). The aldehyde release rate from the imine was shown to depend substantially on the pH from the solution and the air humidity from the solid state.