Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Benzaldehydes”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 955 records · Page 53Linked to original sources
PubMed1994

Identification of the class-3 aldehyde dehydrogenases present in human MCF-7/0 breast adenocarcinoma cells and normal human breast tissue.

Affinity column chromatography was used to semipurify the very small amounts of class-3 aldehyde dehydrogenase (ALDH-3) present in human MCF-7/0 breast adenocarcinoma cells and human normal breast tissue. Characterization of the semipurified enzymes revealed that each was a type-1 ALDH-3 rather than a type-2 ALDH-3 as previously reported. Although clearly a type-1 ALDH-3, the MCF-7/0 enzyme, as well as the type-1 ALDH-3 constitutively present in cultured colon C cells and induced in cultured MCF-7/0 cells by methylcholanthrene, does, however, differ from the prototypical human stomach mucosa type-1 ALDH-3 in one, perhaps pharmacologically important, way, viz. when the ability to catalyse the oxidation of aldophosphamide is normalized by the ability to catalyse the oxidation of benzaldehyde, each of these enzymes, as well as the type-2 ALDH-3 found in MCF-7/OAP cells, exhibits greater ability to catalyse the oxidation of aldophosphamide than does stomach mucosa type-1 ALDH-3; hence, although not type-2 ALDH-3s, they may be slight variants of the prototypical type-1 ALDH-3.

Adenocarcinoma↗
PubMed1988

Spatial coding of olfactory information in the antennal lobe of Drosophila melanogaster.

[3H]2-deoxyglucose autoradiography has revealed foci in the antennal lobe of Drosophila melanogaster that are active during olfactory stimulation. Labelling in the receptor axons and the lobe interneurons can be observed. Each class of odors stimulates activity in a specific subset of antennal glomeruli. This defines the activity domain, which is recognizably distinct, although overlapping, for different classes of volatile chemicals. Unilateral stimulation with attractants predominantly results in excitation of the ipsilateral glomeruli. Collaterals of the receptor neurons to the contralateral lobe stimulate no visible postsynaptic activity. On the other hand, unilateral stimulation with repellent odors, such as benzaldehyde, results in an equally strong activity in both antennal lobes.

Acids↗
PubMed1984

Synthetic mucin fragments: benzyl 2-acetamido-6-O-(2-acetamido-2-deoxy-beta- D-glucopyranosyl)-2-deoxy-3-O-beta-D-galactopyranosyl-alpha-D- galactopyranoside and benzyl 2-acetamido-6-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)- 3-O-[6-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-beta-D- galactopyranosyl]-2-deoxy-alpha-D-galactopyranoside.

Glycosylation of benzyl 2-acetamido-4,6-O-benzylidene-2-deoxy-alpha-D- galactopyranoside with 2,3,4,6-tetra-O-acetyl-alpha-D-galactopyranosyl bromide, catalyzed by mercuric cyanide, afforded benzyl-2-acetamido-4,6-O-benzylidene-2-deoxy-3- O-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-alpha-D- galactopyranoside (3). O-Deacetylation of 3 gave benzyl 2-acetamido-4,6-O-benzylidene-2-deoxy-3-O-beta- D-galactopyranosyl-alpha-D-galactopyranoside which, on acetalation with benzaldehyde-zinc chloride complex followed by acetylation of the resulting dibenzylidene acetal, gave the disaccharide diacetate (7). Cleavage of the acetal groups of 3 and 7 in hot, 80% aqueous acetic acid furnished, respectively, the disaccharide tetraacetate (4) and diacetate (8). O-Deacetylation of 8 in methanolic sodium methoxide gave the disaccharide (9). Condensation of 4 or 8 with 2-methyl-(3,4,6-tri-O-acetyl-1,2- dideoxy-alpha-D-glucopyrano)-[2,1-d]-2-oxazoline, followed by O-deacetylation, afforded the title tri- and tetra-saccharides, 12 and 14, respectively. The structures of compounds 9, 12, and 14 were established by 13C-n.m.r. spectroscopy.

Indicators and Reagents↗
PubMed1981

On interactions of cytostatic benzylidine hydrazines with SH-groups.

The cytostatic and mutagenic compound N'-methyl-N'-cyano-(p-chloro)-benzaldehyde hydrazone (CyB4) has been found to be a strong SH-blocking agent since it reacts with the thiol groups of glutathione and of the cell membrane of Ehrlich ascites carcinoma cells (EAC). Furthermore, it decreases the intracellular, non-proteinogenic SH(NPSH)-level of tumor cells. CyB4 is not able to alkylate 4-(p-nitrobenzyl)-pyridine (NBP) by a nucleophilic substitution reaction, but it could be shown that the reactivity of CyB4 with thiol groups is due to a Michael-addition-type reaction of SH-groups with the cyano-group of CyB4. On the other hand, cytostatic beta-chloroethyl hydrazones showed a negligible reactivity against glutathione and led even to an increase of thiol groups, detectable by the 5,5'-dithiobis-2-nitrobenzoic acid (DTNB)-method, at the cell membrane of EAC when incubated in the presence of beta-chloroethyl hydrazones N-benzylidene-N'-methyl-N'-(2-chloroethyl) hydrazine (B1) and N-(4-dimethylaminobenzylidene)-N'-methyl-N'-(2-chloroethyl) hydrazine (B2). Therefore, it is concluded that the cytostatic efficiency of CyB4 is due to its SH-blocking while that of the beta-chloroethyl hydrazones is due to a rearrangement of the tumor cell membrane, as indicated by the increased level of reactive SH-groups.

Alkylating Agents↗
PubMed1992

Induction of class 3 aldehyde dehydrogenase in the mouse hepatoma cell line Hepa-1 by various chemicals.

The mouse hepatoma cell line Hepa-1 was shown to express an aldehyde dehydrogenase (ALDH) isozyme which was inducible by TCDD and carcinogenic polycyclic aromatic hydrocarbons. The induced activity could be detected with benzaldehyde as substrate and NADP as cofactor (B/NADP ALDH). As compared with rat liver and hepatoma cell lines, the response was moderate (maximally 5-fold). There was an apparent correlation between this specific form of ALDH and aryl hydrocarbon hydroxylase (AHH) in the Hepa-1 wild-type cell line--in terms of inducibility by several chemicals. However, the magnitude of the response was clearly smaller for ALDH than for AHH. Southern blot analysis showed that a homologous gene (class 3 ALDH) was present in the rat and mouse genome. The gene was also expressed in Hepa-1 and there was a good correlation between the increase of class 3 ALDH-specific mRNA and B/NADP ALDH enzyme activity after exposure of the Hepa-1 cells to TCDD. It is concluded that class 3 ALDH is inducible by certain chemicals in the mouse hepatoma cell line, although the respective enzyme is not inducible in mouse liver in vivo.

Aldehyde Dehydrogenase↗
PubMed1986

Highly selective affinity labelling of RNA polymerase B (II) from wheat germ.

DNA-dependent RNA polymerase B (II) from wheat germ was modified by incubation with 4-[N-(beta-hydroxyethyl)-N-methyl]benzaldehyde esters of AMP, ADP or ATP, followed by reduction with NaBH4. Reaction of the modified enzyme with [alpha-32P]UTP in the presence of various DNA templates led to a highly selective affinity labelling of the subunit with Mr 140 000 by covalently linked ApU. Labelling was inhibited by 1 microgram/ml alpha-amanitin.

Affinity Labels↗
PubMed1990

Oxidation of non-phenolic substrates. An expanded role for laccase in lignin biodegradation.

In the presence of substrates such as Remazol Blue and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulphonate) (ABTS), laccases Coriolus (Trametes) versicolor can also oxidize non-phenolic lignin model compounds. Veratryl alcohol (I) and 1-(3,4-dimethoxyphenyl)-2-(2-methoxyphenoxy)-propane-1,3-diol (III) were oxidized by laccase and mediator to give the alpha-carbonyl derivatives. The beta-1 lignin model dimer, 1-(3,4-dimethoxyphenyl)-2-phenoxy-ethane-1,2-diol (II) was cleaved by laccase in the presence of ABTS to give veratraldehyde and benzaldehyde. On the basis of these observations, we propose that laccase is capable of oxidizing both phenolic and non-phenolic moieties of lignin but that the latter is dependent on the co-presence of primary laccase substrates.

Benzyl Alcohols↗
PubMed1988

Purification by affinity chromatography and characterization of porcine liver cytoplasmic polyamine oxidase.

1. Polyamine oxidase was purified from the soluble fraction of porcine liver by more than 70,000-fold to electrophoretic homogeneity using N8-acetylspermidine-Sepharose 4B affinity chromatography. 2. The molecular weight and isoelectric point of this enzyme were 62,000 and pH 4.5, respectively. 3. Optimal pH for the catalytic activity was close to 10.0. 4. The enzyme activity was enhanced by 5 mM dithiothreitol or 5 mM benzaldehyde. 5. Preferential substrates for this cytoplasmic PAO were N1-acetylspermine, N1-acetylspermidine and spermine. 6. Spermidine was not virtually the substrate for this enzyme. 7. The present results suggested the physiological roles of cytoplasmic PAO, being coupled with the reaction of spermidine/spermine N1-acetyltransferase, in recycling the cellular polyamines to putrescine.

Animals↗
PubMed1992

Kinetic behaviour and properties of aldehyde dehydrogenase from rat testis mitochondria. Effect of Mg2+ ions.

1. Mitochondrial aldehyde dehydrogenase is purified to near homogeneity by hydroxylapatite-, affinity- and hydrophobic interaction-chromatography. 2. The enzyme is an oligomeric protein and its molecular weight, as determined by gel-filtration, is 117,000 +/- 5000. 3. Active only in the presence of exogenous sulfhydryl compounds and NAD(+)-dependent, aldehyde dehydrogenase works optimally with linear-chain aliphatic aldehydes and is practically inactive with benzaldehyde. The pH-optimum is at about pH 8.5. 4. Km-Values for aliphatic aldehydes (C2-C6) range between 0.17 and 0.32 microM. The Km for NAD+ increases from 16 microM with acetaldehyde to 71 microM with capronaldehyde. 5. Millimolar concentrations of Mg2+ promote high increases of both V and Km for NAD+. At the same time, saturation curves with C4-C6 aldehydes can be simulated with a substrate inhibition model. 6. Inhibition by NADH is competitive: with capronaldehyde, the inhibition constant for NADH is 52 microM in the absence of Mg2+ and 14 microM in the presence of 4 mM Mg2+; with acetaldehyde, the inhibition constant is about three times higher (36 and 159 microM, respectively).

Aldehyde Dehydrogenase↗
PubMed1990

Hyperthermic and anorectic effects of oxazolidines derived from L-ephedrine in rats.

Oxazolidines synthesized from (-) ephedrine have been proposed as potential pro-drugs, but no pharmacological data on these compounds has been yet reported. In this study, four such compounds are tested in rats for ephedrine-like activity using the hyperthermia and anorexia models. The compounds were synthesized by reaction of (-) ephedrine with salicylaldehyde, acetone, cyclohexanone, and benzaldehyde, respectively. The results showed that all of the compounds decreased food intake significantly, but only the acetone and the salicylaldehyde derivatives caused a significant elevation of body temperature. All of the compounds were less effective than (-) ephedrine in the anorexia model. The acetone and salicylaldehyde derivatives showed similar potency to (-) ephedrine in the hyperthermia model.

Animals↗
PubMed1977

Taste and olfaction in human obesity.

Earlier studies have shown differences between normal weight and obese humans in responsivity to external and internal stimuli. This study shows that normal weight and obese subjects do not differ in hedonic response to sucrose (taste) and benzaldehyde (odor). However, a perceptual typing of individuals based upon hedonic response is possible for both gustatory and olfactory processes. Ratings of pleasantness for the sweet taste of sucrose appear to generalize to the food-related odor of bitter almonds. The method of magnitude estimation as applied to the study of taste and olfaction in man may reveal relationship between changes in internal state and hedonic behavior.

Adult↗
PubMed1984

Quality and intensity of binary odor mixtures.

The perceived intensity and quality of binary mixtures consisting of the common but dissimilar odorants, benzaldehyde (almond), eugenol (cloves), propionic acid (vinegar) and (-)-carvone (spearmint), were determined over a wide range of environmentally relevant concentrations. Consistent data were obtained from each of the odor pairs. This showed that the intensity of odorants not their quality determined the contribution of each to the quality of a mixture. Except for the pair carvone-propionic acid, both odorants were perceived only when the difference between their intensities was small. The results confirmed an earlier finding that the total intensity of a mixture is less than the sum of the intensities of the two components, and also showed that it is never less than the intensity of the weaker component. Seven major characteristics of binary odor mixtures are defined.

Adult↗
PubMed1986

Olfactory and nonolfactory odor detection in pigeons: elucidation by a cardiac acceleration paradigm.

A technique for the Pavlovian conditioning of cardiac acceleration in response to odorants was developed and used to compare the sensitivity of pigeons to four odorants before and after resection of the olfactory nerves. This method provided quite reliable psychophysical functions yet required relatively little training time. Thresholds of normal pigeons to n-amyl acetate, n-butyl acetate, benzaldehyde and butanol were approximately 10(-4), 10(-5), 10(-3.3) and 10(-4.3) of vapor saturation, respectively. Following resection surgery, sensitivity decreased by 2 to 4 log units. When transection of the ophthalmic branch of the trigeminal nerve was combined with olfactory nerve resection, little evidence of a further decline in odor sensitivity was seen. Based on these results each of these compounds could be used, at concentrations below the postoperative threshold, to study, in isolation, both normal and reconstituting olfactory systems in the pigeon.

Animals↗
PubMed1985

Sensory irritation response to inhaled aldehydes after formaldehyde pretreatment.

Pretreatment of Fischer-344 (F-344) rats with formaldehyde (HCHO) induces significant cross tolerance to the sensory irritation properties of Cl2. The purpose of this study was to determine if HCHO pretreatment would cause sensory irritation cross tolerance to other inhaled aldehydes. Male F-344 rats, weighing 190 to 210 g, were pretreated with 15 ppm HCHO, 6 hr/day for 9 days, and challenged on the 10th day with a saturated (acetaldehyde, propionaldehyde, and butyraldehyde), unsaturated (acrolein and crotonaldehyde), or cyclic (cyclohexanecarboxaldehyde, 3-cyclohexene-1-carboxaldehyde, and benzaldehyde) aldehyde. The sensory irritation response in these animals was quantified by measuring respiratory rate depression in a head-only inhalation chamber using plethysmographic techniques. Control animals were challenged identically without prior pretreatment. In naive (nonpretreated) animals, the concentration eliciting a 50% decrease in respiratory rate (RD50) was 23 ppm or less for unsaturated aliphatic aldehydes. For cyclic and saturated aliphatic aldehydes, the RD50 ranged from 600 to 1000 ppm and 3000 to 6800 ppm, respectively. Formaldehyde pretreatment resulted in cross tolerance only with acetaldehyde (RD50 increased 3.5-fold) and acrolein (RD50 increased 5-fold). These results indicate that the development of cross tolerance following HCHO pretreatment is not a general phenomenon. Prediction of acceptable concentrations of occupational exposure for the prevention of sensory irritation in humans has been based primarily on RD50 data for mice. Comparison of the RD50 values obtained for rats in this investigation with previously published results for mice varied by over one-half an order of magnitude, thereby disputing the usefulness of data from F-344 rats in setting threshold limit values for the prevention of sensory irritation.

Aldehydes↗
PubMed1988

Substrate preference of a cytosolic aldehyde dehydrogenase inducible in rat liver by treatment with 3-methylcholanthrene.

The substrate preference of an aldehyde dehydrogenase induced in rat liver cytosol by 3-methylcholanthrene was examined. This enzyme, T-ALDH, is identical to the aldehyde dehydrogenase inducible in rat liver by 2,3,7,8-tetrachloro-dibenzo-p-dioxin and the tumor-associated aldehyde dehydrogenase found in rat hepatocellular neoplasms. With either NAD or NADP as coenzyme, the preferred substrates were the aliphatic aldehydes n-hexanal, n-nonanal, and isobutyraldehyde and the aromatic aldehydes 2,5-dihydroxybenzaldehyde, benzaldehyde, and 3-hydroxybenzaldehyde. The results indicate that T-ALDH may play a role in oxidizing a variety of aldehydes produced in physiological lipid metabolism. On the contrary, this isozyme does not seem to participate in the oxidation of small aliphatic aldehydes generated during lipid peroxidation. Similarly, no significant activity could be detected when the enzyme was tested with aldehydes produced in carbohydrate, amino acid, polyamine, steroid, and vitamin metabolism.

Aldehyde Dehydrogenase↗
PubMed1991

Induction of cytochrome P450 and other drug metabolizing enzymes in rat liver following dietary exposure to Aroclor 1254.

Selected drug metabolizing activities were measured in female F344/NCr rats exposed to graded dietary concentrations of Aroclor 1254 (1 to 1000 ppm) for 7 days or to lower concentrations of Aroclor (1 to 10 ppm) for up to 28 days. Following the 7-day exposure, the hepatic O-dealkylation of ethoxyresorufin (ETR), mediated primarily by cytochrome P450IA, was increased 60-, 10-, and 4-fold by 33, 10, and 3 ppm Aroclor, respectively. In rats exposed to 10 and 3 ppm Aroclor for 28 days, this activity was increased approximately 30- and 10-fold, respectively. Hepatic ETR O-dealkylase activities correlated with Aroclor concentrations in the livers of exposed rats (r = 0.99, p less than 0.01). Although the O-dealkylation of benzyloxyresorufin was highly increased by 7-days dietary exposure to 1000 ppm Aroclor, the levels of Aroclor necessary for detection of induction were substantially higher than those required for detection of ETR O-dealkylase induction. Examination of the non-P450-mediated drug metabolizing activities, epoxide hydrolase and DT-diaphorase, similarly showed limited (approximately 10-fold) increases. In contrast, aldehyde dehydrogenase (benzaldehyde, NADP+) activity was highly increased (greater than 40-fold) at 1000 ppm, however this activity was increased to only a limited extent at lower Aroclor concentrations (e.g. approximately 3-fold at 33 ppm). These results support the potential use of cytochrome P450 activities as potential biomarkers for environmental exposure to PCBs and related compounds.

Aldehyde Dehydrogenase↗
PubMed1983

Inhibition of ethanol- and aldehyde-induced release of ethane from isolated perfused rat liver by pargyline and disulfiram.

Acute addition of ethanol or acetaldehyde to the isolated, perfused rat liver leads to an increase in ethane and n-pentane release. These volatile hydrocarbons are known to originate from the peroxidation of polyunsaturated fatty acids. The effects are half-maximal at 0.5 mM ethanol or 20 microM acetaldehyde in the entering perfusate. Propionaldehyde and benzaldehyde are also able to elicit ethane release. Pargyline and disulfiram, inhibitors of aldehyde oxidation, inhibited the extra ethane release in all cases. The inhibitory effect of pargyline is suppressed during addition of metyrapone. The study indicates that the oxidation of acetaldehyde and not of ethanol itself is the step responsible for increased ethane formation by the perfused rat liver during ethanol infusion.

Acetaldehyde↗
PubMed1992

Behavioral and enzymatic interactions between benzyl alcohol and ethanol.

Acute IP injection of benzyl alcohol but not benzaldehyde (0.5 g/kg) caused aversion to voluntary drinking of 5% ethanol solution by male rats with preference to ethanol. Benzyl alcohol noncompetitively inhibited hepatic alcohol dehydrogenase of rats maintained for a short term on 5% ethanol compared to control. The results suggest an adverse interaction between benzyl alcohol and ethanol underlying the observed aversion to ethanol.

Alcohol Dehydrogenase↗