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Journal of Equine Veterinary Science Sep 2019Alcohol-based antisepsis has been extensively studied in human health care, but only little information is available regarding efficacy and tolerance in other species....
Alcohol-based antisepsis has been extensively studied in human health care, but only little information is available regarding efficacy and tolerance in other species. The purpose of this study was to determine if an alcohol-based antiseptic is effective at reducing bacterial counts on equine skin and the appropriate contact time to do so, without causing any adverse skin reactions. Samples were collected before and after preparation from clipped sites over both jugular veins of horses and were plated on 3M Petrifilm Aerobic Count Plates in duplicate. Trial 1 tested an alcohol-based product (ET-80% ethanol) against a control of sterile saline at a contact time of 180-second. Trial 2 tested two different contact times of ET-90 and 180 seconds. All samples were assessed for colony-forming unit counts using an automated 3M Petrifilm reader. Data were analyzed by Kruskal-Wallis test, and the significance was set at P < .05. The results determined that ET had a mean 2.95 log reduction from prepreparation to postpreparation colony-forming unit counts. A significant difference in log reduction between ET and control (P = .0033) was observed. There was no difference in log reduction between the two contact times (P = .75). Mild urticaria was the only skin reaction observed and was often present in both ET and control groups. These findings demonstrate that ET is effective at reducing bacterial counts on equine skin at a contact time of 90 seconds without producing significant adverse skin reaction.
Topics: 2-Propanol; Animals; Anti-Infective Agents, Local; Antisepsis; Ethanol; Horses; Humans; Skin
PubMed: 31443836
DOI: 10.1016/j.jevs.2019.06.004 -
Regulatory Toxicology and Pharmacology... Nov 2019Read-across and grouping is one of the most commonly used alternative approaches for data gap filling in registrations submitted under the REACH Regulation as defined by... (Review)
Review
Read-across and grouping is one of the most commonly used alternative approaches for data gap filling in registrations submitted under the REACH Regulation as defined by the European Chemicals Agency (ECHA) in their 'Read-Across Assessment Framework' (RAAF, 2017). At the same time, the application of read-across is rejected by ECHA frequently due to various reasons. As a major reason hereof, applicants fail to reduce the level of 'remaining uncertainty' intrinsical to every read-across approach compared to testing a substance experimentally. Recently, the use of metabolomics to support read-across cases with biological information has been reported in a case study with phenoxy herbicides (Ravenzwaay et al., 2016). In the present case-study a 'weight-of-evidence' read-across approach from 2-aminoethanol (MEA = 'source') to 3-aminopropanol (3AP = 'target') with metabolomics as 'supporting evidence' reducing the remaining uncertainties is reported. We demonstrate the high structural similarity of the two analogous substances based on the available data and we report how metabolome data add confidence concerning mechanistic similarity in this read-across approach. Finally, the herein described read-across case supported by metabolomics is used to cover the data gaps in repeated dose and reproductive toxicity endpoint of 3AP via weight of evidence for the REACH-registration.
Topics: Animals; Ethanolamine; Female; Male; Metabolome; Metabolomics; Propanolamines; Rats, Wistar; Risk Assessment; Toxicity Tests
PubMed: 31421187
DOI: 10.1016/j.yrtph.2019.104442 -
Environmental Microbiology Jan 2021Acetobacterium woodii utilizes the Wood-Ljungdahl pathway for reductive synthesis of acetate from carbon dioxide. However, A. woodii can also perform non-acetogenic...
Acetobacterium woodii utilizes the Wood-Ljungdahl pathway for reductive synthesis of acetate from carbon dioxide. However, A. woodii can also perform non-acetogenic growth on 1,2-propanediol (1,2-PD) where instead of acetate, equal amounts of propionate and propanol are produced as metabolic end products. Metabolism of 1,2-PD occurs via encapsulated metabolic enzymes within large proteinaceous bodies called bacterial microcompartments. While the genome of A. woodii harbours 11 genes encoding putative alcohol dehydrogenases, the BMC-encapsulated propanol-generating alcohol dehydrogenase remains unidentified. Here, we show that Adh4 of A. woodii is the alcohol dehydrogenase required for propanol/ethanol formation within these microcompartments. It catalyses the NADH-dependent reduction of propionaldehyde or acetaldehyde to propanol or ethanol and primarily functions to recycle NADH within the BMC. Removal of adh4 gene from the A. woodii genome resulted in slow growth on 1,2-PD and the mutant displayed reduced propanol and enhanced propionate formation as a metabolic end product. In sum, the data suggest that Adh4 is responsible for propanol formation within the BMC and is involved in redox balancing in the acetogen, A. woodii.
Topics: 1-Propanol; Acetaldehyde; Acetates; Acetobacterium; Alcohol Dehydrogenase; Aldehydes; Bacterial Proteins; Carbon Dioxide; Ethanol; Genome, Bacterial; NAD; Oxidation-Reduction
PubMed: 33283462
DOI: 10.1111/1462-2920.15340 -
International Journal of Environmental... Jan 2024Accurate determination of the concentration of alcohols and their metabolites is important in forensics and in several life science areas. A new headspace gas...
Accurate determination of the concentration of alcohols and their metabolites is important in forensics and in several life science areas. A new headspace gas chromatography-mass spectrometry method has been developed to quantify alcohols and their oxidative products using isotope-labeled internal standards. The limit of detection (LOD) of the analytes in the developed method was 0.211 µg/mL for methanol, 0.158 µg/mL for ethanol, 0.157 µg/mL for isopropanol, 0.010 µg/mL for n-propanol, 0.157 µg/mL for acetone, and 0.209 µg/mL for acetaldehyde. The precision and accuracy of the method were evaluated, and the relative standard deviation percentages were found to be less than 3%. This work demonstrates the application of this method, specifically in quantifying the concentration of oxidative products of alcohol and other minor alcohols found in hand sanitizers, which have become an essential household item since the COVID-19 pandemic. Apart from the major components, the minor alcohols found in hand sanitizers include methanol, isopropanol, and n-propanol. The concentration range of these minor alcohols found in ethanol-based hand sanitizer samples was as follows: methanol, 0.000921-0.0151 mg/mL; isopropanol, 0.454-13.8 mg/mL; and n-propanol, 0.00474-0.152 mg/mL. In ethanol-based hand sanitizers, a significant amount of acetaldehyde (0.00623-0.231 mg/mL) was observed as an oxidation product, while in the isopropanol-based hand sanitizer, acetone (0.697 mg/mL) was observed as an oxidation product. The concentration of acetaldehyde in ethanol-based hand sanitizers significantly increased with storage time and temperature, whereas no such increase in acetone concentration was observed in isopropanol-based hand sanitizers with storage time and temperature. In two of the selected hand sanitizers, the acetaldehyde levels increased by almost 200% within a week when stored at room temperature. Additionally, exposing the hand sanitizers to a temperature of 45 °C for 24 h resulted in a 100% increase in acetaldehyde concentration. On the contrary, the acetone level remained constant upon the change in storage time and temperature.
Topics: Humans; Methanol; Acetaldehyde; Hand Sanitizers; Acetone; 2-Propanol; 1-Propanol; Temperature; Gas Chromatography-Mass Spectrometry; Pandemics; Ethanol
PubMed: 38248538
DOI: 10.3390/ijerph21010074 -
ACS Sensors Jan 2023As an important biomarker of lung cancer, -propanol at the sub-ppm level is still challenging to be detected for a simple and immediate early diagnosis. In this work, a...
As an important biomarker of lung cancer, -propanol at the sub-ppm level is still challenging to be detected for a simple and immediate early diagnosis. In this work, a new -propanol gas sensor with an ultralow detection limit down to 100 ppb is presented using AgCrO nanoparticles synthesized by a simple hydrothermal method. Compared with the congeneric CuCrO and commercial SnO, AgCrO exhibits prevailing performances, including a higher selectivity, dynamic response, and logarithmical linearity but lower working temperature. The first-principles calculation and the energy band theoretical analysis are combined to elucidate the sensing mechanism, in which the chemical adsorption of gaseous molecules to silver followed by the dehydrogenation on chromium on the surface of AgCrO is responsible for the outstanding susceptibility toward -propanol. The proposed metal oxide semiconductor gas sensor capable of sub-ppm -propanol detection provides a route to design and optimize the sensitive material system for the advanced trace detection of the volatile organic compounds.
Topics: 1-Propanol; Propanols; Nanoparticles; Adsorption; Chromium; Gases
PubMed: 36584336
DOI: 10.1021/acssensors.2c02182 -
BMC Microbiology Feb 2021Degradation of acetone by aerobic and nitrate-reducing bacteria can proceed via carboxylation to acetoacetate and subsequent thiolytic cleavage to two acetyl residues. A...
BACKGROUND
Degradation of acetone by aerobic and nitrate-reducing bacteria can proceed via carboxylation to acetoacetate and subsequent thiolytic cleavage to two acetyl residues. A different strategy was identified in the sulfate-reducing bacterium Desulfococcus biacutus that involves formylation of acetone to 2-hydroxyisobutyryl-CoA.
RESULTS
Utilization of short-chain ketones (acetone, butanone, 2-pentanone and 3-pentanone) and isopropanol by the sulfate reducer Desulfosarcina cetonica was investigated by differential proteome analyses and enzyme assays. Two-dimensional protein gel electrophoresis indicated that D. cetonica during growth with acetone expresses enzymes homologous to those described for Desulfococcus biacutus: a thiamine diphosphate (TDP)-requiring enzyme, two subunits of a B-dependent mutase, and a NAD-dependent dehydrogenase. Total proteomics of cell-free extracts confirmed these results and identified several additional ketone-inducible proteins. Acetone is activated, most likely mediated by the TDP-dependent enzyme, to a branched-chain CoA-ester, 2-hydroxyisobutyryl-CoA. This compound is linearized to 3-hydroxybutyryl-CoA by a coenzyme B-dependent mutase followed by oxidation to acetoacetyl-CoA by a dehydrogenase. Proteomic analysis of isopropanol- and butanone-grown cells revealed the expression of a set of enzymes identical to that expressed during growth with acetone. Enzyme assays with cell-free extract of isopropanol- and butanone-grown cells support a B-dependent isomerization. After growth with 2-pentanone or 3-pentanone, similar protein patterns were observed in cell-free extracts as those found after growth with acetone.
CONCLUSIONS
According to these results, butanone and isopropanol, as well as the two pentanone isomers, are degraded by the same enzymes that are used also in acetone degradation. Our results indicate that the degradation of several short-chain ketones appears to be initiated by TDP-dependent formylation in sulfate-reducing bacteria.
Topics: 2-Propanol; Acetone; Deltaproteobacteria; Ketones; Oxidation-Reduction; Proteome; Proteomics; Sulfates
PubMed: 33593288
DOI: 10.1186/s12866-021-02112-6 -
Bioresource Technology Sep 2019Production of butanol for fuel via the conventional Acetone-Butanol-Ethanol fermentation has been considered economically risky because of a potential oversupply of... (Review)
Review
Production of butanol for fuel via the conventional Acetone-Butanol-Ethanol fermentation has been considered economically risky because of a potential oversupply of acetone. Alternatively, acetone is converted into isopropanol by specific solventogenic Clostridium species in the Isopropanol-Butanol-Ethanol (IBE) fermentation. This route, although less efficient, has been gaining attention because IBE mixtures are a potential fuel. The present work is dedicated to reviewing past and recent advances in microorganisms, feedstock, and fermentation equipment for IBE production. In our analysis we demonstrate the importance of novel engineered IBE-producing Clostridium strains and cell retention systems to decrease the staggering number of fermentation tanks required by IBE plants equipped with conventional technology. We also summarize the recent progress on recovery techniques integrated with fermentation, especially gas stripping. In addition, we assessed ongoing pilot-plant efforts that have been enabling IBE production from woody feedstock.
Topics: 2-Propanol; Acetone; Butanols; Ethanol; Fermentation
PubMed: 31085056
DOI: 10.1016/j.biortech.2019.121425 -
Inhalation Toxicology 2020The inhalation of air-borne toxicants is associated with adverse health outcomes which can be somewhat mitigated by enhancing endogenous anti-oxidant capacity. Carnosine...
OBJECTIVE
The inhalation of air-borne toxicants is associated with adverse health outcomes which can be somewhat mitigated by enhancing endogenous anti-oxidant capacity. Carnosine is a naturally occurring dipeptide (β-alanine-L-histidine), present in high abundance in skeletal and cardiac muscle. This multi-functional dipeptide has anti-oxidant properties, can buffer intracellular pH, chelate metals, and sequester aldehydes such as acrolein. Due to these chemical properties, carnosine may be protective against inhaled pollutants which can contain metals and aldehydes and can stimulate the generation of electrophiles in exposed tissues. Thus, assessment of carnosine levels, or levels of its acrolein conjugates (carnosine-propanal and carnosine-propanol) may inform on level of exposure and risk assessment.
METHODS
We used established mass spectroscopy methods to measure levels of urinary carnosine ( = 605) and its conjugates with acrolein ( = 561) in a subset of participants in the Louisville Healthy Heart Study (mean age = 51 ± 10; 52% male). We then determined associations between these measures and air pollution exposure and smoking behavior using statistical modeling approaches.
RESULTS
We found that higher levels of non-conjugated carnosine, carnosine-propanal, and carnosine-propanol were significantly associated with males ( < 0.02) and those of Caucasian ethnicity ( < 0.02). Levels of carnosine-propanol were significantly higher in never-smokers ( = 0.001) but lower in current smokers ( = 0.037). This conjugate also demonstrated a negative association with mean-daily particulate air pollution (PM) levels ( = 0.01).
CONCLUSIONS
These findings suggest that urinary levels of carnosine-propanol may inform as to risk from inhaled pollutants.
Topics: 1-Propanol; Adult; Air Pollutants; Aldehydes; Biological Monitoring; Carnosine; Female; Humans; Inhalation Exposure; Male; Middle Aged; Smoking
PubMed: 33179563
DOI: 10.1080/08958378.2020.1845257 -
Applied and Environmental Microbiology May 2022Isopropanol dehydrogenase (IPADH) is one of the most attractive options for nicotinamide cofactor regeneration due to its low cost and simple downstream processing....
Isopropanol dehydrogenase (IPADH) is one of the most attractive options for nicotinamide cofactor regeneration due to its low cost and simple downstream processing. However, poor thermostability and strict cofactor dependency hinder its practical application for bioconversions. In this study, we simultaneously improved the thermostability (433-fold) and catalytic activity (3.3-fold) of IPADH from Brucella suis via a flexible segment engineering strategy. Meanwhile, the cofactor preference of IPADH was successfully switched from NAD(H) to NADP(H) by 1.23 × 10-fold. When these variants were employed in three typical bioredox reactions to drive the synthesis of important chiral pharmaceutical building blocks, they outperformed the commonly used cofactor regeneration systems (glucose dehydrogenase [GDH], formate dehydrogenase [FDH], and lactate dehydrogenase [LDH]) with respect to efficiency of cofactor regeneration. Overall, our study provides two promising IPADH variants with complementary cofactor specificities that have great potential for wide applications. Oxidoreductases represent one group of the most important biocatalysts for synthesis of various chiral synthons. However, their practical application was hindered by the expensive nicotinamide cofactors used. Isopropanol dehydrogenase (IPADH) is one of the most attractive biocatalysts for nicotinamide cofactor regeneration. However, poor thermostability and strict cofactor dependency hinder its practical application. In this work, the thermostability and catalytic activity of an IPADH were simultaneously improved via a flexible segment engineering strategy. Meanwhile, the cofactor preference of IPADH was successfully switched from NAD(H) to NADP(H). The resultant variants show great potential for regeneration of nicotinamide cofactors, and the engineering strategy might serve as a useful approach for future engineering of other oxidoreductases.
Topics: 2-Propanol; Formate Dehydrogenases; NAD; NADP; Niacinamide; Regeneration
PubMed: 35442081
DOI: 10.1128/aem.00341-22 -
ChemSusChem Oct 2022Upcoming biorefineries, such as lignin-first provide renewable aromatics containing unique aliphatic alcohols. In this context, a Cu-ZrO catalyzed hydrogen borrowing...
Upcoming biorefineries, such as lignin-first provide renewable aromatics containing unique aliphatic alcohols. In this context, a Cu-ZrO catalyzed hydrogen borrowing approach was established to yield tertiary amine from the lignin model monomer 3-(3,4-dimethoxyphenyl)-1-propanol and the actual lignin-derived monomers, (3-(4-hydroxyphenyl)-1-propanol and dihydroconiferyl alcohol), with dimethylamine. Various industrial metal catalysts were evaluated, resulting in nearly quantitative mass balances for most catalysts. Identified intermediates, side and reaction products were placed into a corresponding reaction network, supported by kinetic evolution experiments. Cu-ZrO was selected as most suitable catalyst combining high alcohol conversion with respectable aliphatic tertiary amine selectivity. Low pressure H was key for high catalyst activity and tertiary amine selectivity, mainly by hindering undesired reactant dimethylamine disproportionation and alcohol amidation. Besides dimethylamine model, diverse secondary amine reactants were tested with moderate to high tertiary amine yields. As most active catalytic site, highly dispersed Cu species in strong contact with ZrO is suggested. ToF-SIMS, N O chemisorption, TGA and XPS of spent Cu-ZrO revealed that imperfect amine product desorption and declining surface Cu lowered the catalytic activity upon catalyst reuse, while thermal reduction readily restored the initial activity and selectivity demonstrating catalyst reuse.
Topics: 1-Propanol; Amines; Catalysis; Copper; Dimethylamines; Ethanol; Hydrogen; Lignin
PubMed: 35900053
DOI: 10.1002/cssc.202200868