Artykuły w czasopismach na temat „Alcohols”
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Karkoulias, Kiriakos, Haralampos Tsitsaras, Dimitrios Patouchas, Fotis Sampsonas, Dimostenis Likouras, Alexander Kaparianos i Kostas Spiropoulos. "The alcoholic lung disease: Historical background and clinical features". Medicina 44, nr 9 (22.10.2007): 651. http://dx.doi.org/10.3390/medicina44090084.
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The purpose of this review article is to prove the damage that alcohol causes to the respiratory system. We will make a brief review of alcohols history in the course of the centuries till nowadays. The problem of addiction to alcohol (alcoholism) will be examined for several countries. Alcohol’s metabolism is another topic to be discussed parallel to its pharmacological action. In addition, alcohol’s impact on the respiratory system varies from damaging the mucociliary system to the regulation of breathing and from the sleep apnea syndrome to diffusion disorders. “Alcoholic lung disease” constitutes a syndrome despite the fact that the damage of the lung due to concurrent smoking and drug use is often indistinguishable.
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Solodun, Yuriy, Yulia Monakhova, Thomas Kuballa, Andriy Samokhvalov, Jürgen Rehm i Dirk Lachenmeier. "Unrecorded alcohol consumption in Russia: toxic denaturants and disinfectants pose additional risks". Interdisciplinary Toxicology 4, nr 4 (1.12.2011): 198–205. http://dx.doi.org/10.2478/v10102-011-0030-x.
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Unrecorded alcohol consumption in Russia: toxic denaturants and disinfectants pose additional risksIn 2005, 30% of all alcohol consumption in Russia was unrecorded. This paper describes the chemical composition of unrecorded and low cost alcohol, including a toxicological evaluation. Alcohol products (n=22) from both recorded and unrecorded sources were obtained from three Russian cities (Saratov, Lipetsk and Irkutsk) and were chemically analyzed. Unrecorded alcohols included homemade samogons, medicinal alcohols and surrogate alcohols. Analysis included alcoholic strength, levels of volatile compounds (methanol, acetaldehyde, higher alcohols), ethyl carbamate, diethyl phthalate (DEP) and polyhexamethyleneguanidine hydrochloride (PHMG). Single samples showed contamination with DEP (275-1269 mg/l) and PHMG (515 mg/l) above levels of toxicological concern. Our detailed chemical analysis of Russian alcohols showed that the composition of vodka, samogon and medicinal alcohols generally did not raise major public health concerns other than for ethanol. It was shown, however, that concentration levels of DEP and PHMG in some surrogate alcohols make these samples unfit for human consumption as even moderate drinking would exceed acceptable daily intakes.
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Florido-Barba, Antonio, Gustavo Cordero-Bueso i Jesús Manuel Cantoral. "Alcoholes no vínicos para la mejora del desarrollo del velo de flor y de las características sensoriales de los vinos Finos de la D.O. Jerez-Xérèz-Sherry". BIO Web of Conferences 68 (2023): 02011. http://dx.doi.org/10.1051/bioconf/20236802011.
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Abstract The wines produced in the Jerez-Xérès-Sherry Designation of Origin fall within the category of Fortified Wines, according to Regulation 1308/2013 of the European Parliament, which stipulates that they must be exclusively fortified with wine alcohol, with an acquired alcoholic strength between 95.0% and 96.0%. However, there are other alternative alcohols whose behavior is unknown but could be equally effective in the development of biological aging, with an impact on the final product quality and lower economic costs. This study examines the effect of using malt alcohols, grape pomace, agave, sugarcane, and cereal alcohols, as well as wine alcohols obtained through different distillation methods and at varying alcohol concentrations, for fortifying wines subjected to biological aging. The development of the "flor" yeast veil will be evaluated under each aging condition and isolated and characterized using molecular techniques. Additionally, the base wine fortified with the different alcohols will be monitored and analyzed both physicochemically and organoleptically.
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Wang, Ya-Ping, Lin Liu, Xue-Shan Wang, Kun-Qiang Hong, Li-Hua Zhang, Zhong-Guan Sun i Dong-Guang Xiao. "GAT1 Gene, the GATA Transcription Activator, Regulates the Production of Higher Alcohol during Wheat Beer Fermentation by Saccharomyces cerevisiae". Bioengineering 8, nr 5 (8.05.2021): 61. http://dx.doi.org/10.3390/bioengineering8050061.
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Uncoordinated carbon-nitrogen ratio in raw materials will lead to excessive contents of higher alcohols in alcoholic beverages. The effect of GAT1 gene, the GATA transcription activator, on higher alcohol biosynthesis was investigated to clarify the mechanism of Saccharomyces cerevisiae regulating higher alcohol metabolism under high concentrations of free amino nitrogen (FAN). The availability of FAN by strain SDT1K with a GAT1 double-copy deletion was 28.31% lower than that of parent strain S17, and the yield of higher alcohols was 33.91% lower. The transcript levels of the downstream target genes of GAT1 and higher alcohol production in the double-copy deletion mutant suggested that a part of the effect of GAT1 deletion on higher alcohol production was the downregulation of GAP1, ARO9, and ARO10. This study shows that GATA factors can effectively regulate the metabolism of higher alcohols in S. cerevisiae and provides valuable insights into higher alcohol biosynthesis, showing great significance for the wheat beer industry.
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Woo, Kang-Lyung. "Determination of Low MolecularWeight Alcohols Including Fusel Oil in Various Samples by Diethyl Ether Extraction and Capillary Gas Chromatography". Journal of AOAC INTERNATIONAL 88, nr 5 (1.09.2005): 1419–27. http://dx.doi.org/10.1093/jaoac/88.5.1419.
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Abstract Low molecular weight alcohols including fusel oil were determined using diethyl ether extraction and capillary gas chromatography. Twelve kinds of alcohols were successfully resolved on the HP-FFAP (polyethylene glycol) capillary column. The diethyl ether extraction method was very useful for the analysis of alcohols in alcoholic beverages and biological samples with excellent cleanliness of the resulting chromatograms and high sensitivity compared to the direct injection method. Calibration graphs for all standard alcohols showed good linearity in the concentration range used, 0.001–2% (w/v) for all alcohols. Salting out effects were significant (p < 0.01) for the low molecular weight alcohols methanol, isopropanol, propanol, 2-butanol, n-butanol and ethanol, but not for the relatively high molecular weight alcohols amyl alcohol, isoamyl alcohol, and heptanol. The coefficients of variation of the relative molar responses were less than 5% for all of the alcohols. The limits of detection and quantitation were 1–5 and 10–60 μg/L for the diethyl ether extraction method, and 10–50 and 100–350 g/L for the direct injection method, respectively. The retention times and relative retention times of standard alcohols were significantly shifted in the direct injection method when the injection volumes were changed, even with the same analysis conditions, but they were not influenced in the diethyl ether extraction method. The recoveries by the diethyl ether extraction method were greater than 95% for all samples and greater than 97% for biological samples.
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Gutierrez, L. E. "Effect of some vitamins and micronutrient deficiencies on the production of higher alcohols by Saccharomyces cerevisiae". Scientia Agricola 50, nr 3 (grudzień 1993): 484–89. http://dx.doi.org/10.1590/s0103-90161993000300024.
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A study was carried out in order to determine the effect of vitamins (biotin, thiamine, pantotheniic acid and pyridoxal) and micronutrient (zinc, boron, manganese and iron) deficiencies on higher alcohol production during alcoholic fermentation with the industrially used yeast Saccharomyces cerevisiae M-300-A. Zinc deficiency induced a reduction on the levels of isobutyl and isoamyl alcohols. An increase on isobutyl alcohol (fivefold) and a reduction of isoamyl alcohol (two fold) and n-propyl alcohol (three fold) contents resulted from pantotheiiic acid deficiency, whereas pyridoxal deficiency caused an increase on the levels of isobutyl and isoamyl alcohols. Biotin was not essential for the growth of this strain.
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Maia, Amazile Biagioni, Lorena Simão Marinho i David Lee Nelson. "On the role of higher alcohols in the characterization of cachaça". Research, Society and Development 9, nr 10 (21.10.2020): e8299109135. http://dx.doi.org/10.33448/rsd-v9i10.9135.
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There is a growing interest in chemical markers for the identification and certification of cachaça as a cane spirit produced in Brazil. It is known that the higher alcohols that are usually analyzed (propyl alcohol, Isobutyl alcohol and isoamyl alcohol) occur in all alcoholic beverages (fermented and distilled), but the relative proportions can vary markedly according to the peculiarities of the raw material and the production process. In this work, the contents of higher alcohols in 300 samples of alembic cachaça were compared, 220 from the state of Minas Gerais and 80 from other states, as well as three samples of industrial cachaça and 14 samples of whiskeys of various brands. The typical range of total higher alcohols in cachaça was 180-360 mg/100 mL ethanol. Cachaça containing higher alcohol concentrations greater than 360 mg/100 mL ethanol do not comply with Brazilian legislation. However, cachaças with higher alcohols concentrations below 180 mg/100 mL ethanol, as was found in one of the industrial cachaças, signify adulteration, for example, by mixing with fuel alcohol. The C4/C5 ratio varied less than the C3/C5 ratio, being consistently within the range of 0.20-0.50. In the whiskeys analyzed, the concentrations of higher alcohols were in the range of 160 and 270 mg/100 mL. Therefore, this parameter would not assist in differentiating between cachaça and whiskey. But the C4/C5 ratio was consistently different, being always greater than 0.50 for the whiskeys. Thus, the routine analysis of higher alcohols provides useful information both for tracking possible fraud and for assessments related to the identity or origin of cachaça.
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Gil, Artyom, Sergey Savchuk, Svetlana Appolonova, Andrey Allenov i Ruslan Khalfin. "AVAILABILITY OF NON-BEVERAGE ALCOHOLS IN RUSSIA IN 2015-2020: WERE CONTROL POLICIES IMPLEMENTED SINCE 2005 EFFECTIVE?" Journal of Law, Public Policies, and Human Sciences 2, nr 2 (20.04.2021): 08–34. http://dx.doi.org/10.52571/jlpphs.v02.n02.pgi.08.2021.
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Consumption of non-beverage alcohol is an important aspect of hazardous drinking, impacting mortality from various causes of death. Since 2005, non-beverage alcohols in Russia have been the subject of active regulation to control their consumption for drinking. This study was purported to determine whether non-beverage alcohols were available in Russia in 2015–2020 to assess the effectiveness of implemented control policies. During the first wave of the survey between 2015 and 2017, 50 Russian cities of various sizes, types, and locations were surveyed. The second wave was conducted between 2018 and 2020 in 5 cities, which were surveyed during the first wave. Fieldworkers visited various retail outlets and purchased samples of non-beverage alcohols: spirituous liquids with an ethanol content of at least 60% by volume sold at a price of less than 45 roubles per bottle ($0.57, €0.49, £0.44). Up until 2016 various types of non-beverage alcohols known as consumed for drinking were available in retail. The availability of these alcohols differed between cities depending on the level of local enforcement of control regulations. The regulations enacted in response to the 2016 Irkutsk outbreak of mass alcohol poisonings, caused by the consumption of methanol containing fake bath additive “Hawthorn”, removed from the market several types of non-beverage alcohols, significantly reducing their availability since 2017. However, low-cost ethanol sources, such as medicinal tinctures, antiseptics, not denatured eau-de-colognes, remained available in 2017-2020, while new sorts of cheap non-beverage alcohols suitable for drinking were introduced to the market (antiseptics for veterinary use, anti-SARS-CoV-2 hand sanitizers). Illegal alcoholic beverages commonly produced from diverted pharmaceutical/medicinal ethanol were also available in retail networks selling non-beverage alcohols. Since 2005, policies implemented and especially those reinforced and newly enacted in 2017 and later in response to the 2016 Irkutsk outbreak, may have indeed reduced the physical availability of non-beverage alcohols. However, more decisive action is still required to prevent consumption of newly appearing and existing specific sorts of non-beverage alcohols and illegal alcoholic beverages, which are commonly produced from the licit or diverted from the legal market unrecorded illicit pharmaceutical/medicinal ethanol.
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Wang, Bei, Liu Tao, Yu Cheng, Fang Yang, Yuguang Jin, Chunmei Zhou, Hao Yu i Yanhui Yang. "Electrocatalytic Oxidation of Small Molecule Alcohols over Pt, Pd, and Au Catalysts: The Effect of Alcohol’s Hydrogen Bond Donation Ability and Molecular Structure Properties". Catalysts 9, nr 4 (25.04.2019): 387. http://dx.doi.org/10.3390/catal9040387.
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The direct alcohol fuel cell is a kind of power generation device that directly converts the chemical energy of small molecule alcohols into electric energy. In this paper, the electro-oxidation behaviors of some typical alcohols (methanol, ethanol, ethylene glycol, n-propanol, 2-propanol, and glycerol) over Pt, Pd, and Au electrodes were investigated in acidic, neutral, and alkaline media, respectively. By analyzing the activity information from a cyclic voltammetry (CV) method and some dynamic tests, several regularities were revealed in those electro-oxidation behaviors. Firstly, alkaline media is the best for the electro-oxidation of all these alcohols over Pt, Pd, and Au catalysts. Secondly, the hydrogen bond donation abilities (HBD) of different alcohols were found have a great relationship with the catalytic performance. In alkaline media, on Pt electrodes, the solute HBD is positively correlated with the ease of electrooxidation within the scope of this experiment. Contrarily, it is negatively correlated on Pd and Au electrodes. Additionally, for Pt catalysts in acidic and neutral media, the relationship becomes negative again as the HBD increases. Finally, the alcohol’s molecular structure properties were found to have a remarkably influence on the activity of different catalysts. Over the Pt electrode in alkaline media, the activation energy of methanol oxidation is 44.1 KJ/mol, and is obviously lower than the oxidation of other alcohols. Under similar conditions, the lowest activation energy was measured in the oxidation of n-propanol (14.4 KJ/mol) over the Pd electrode, and in the oxidation of glycerol (42.2 KJ/mol) over the Au electrode. Totally, among all these electrodes, Pt electrodes showed the best activities on the oxidation of C1 alcohol, Pd electrodes were more active on the oxidation of C2-3 monobasic alcohols, and Au electrodes were more active on the oxidation of polybasic alcohols.
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Bakanov, Vyacheslav Vadimovich, Dmitriy Nikolaevich Vedernikov i Lyubov Sergeevna Khabarova. "EXTRACTIVE SUBSTANCES OF SAPROTROPHIC MUSHROOMS LENTINULA EDODES AND PHOLIOTA SQUARROSA. HEAVY METAL CONTENT". chemistry of plant raw material, nr 3 (22.10.2020): 67–72. http://dx.doi.org/10.14258/jcprm.2020037277.
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The article is devoted to comparing the chemical composition of extractive substances of the legs and caps of two types of saprotrophic fungi Lentinula edodes and Pholiota squarrosa. The content of metals: mercury, cadmium and iron in different parts of the mushrooms is compared in the article. The amount of substances recovered by various solvents is determined. The amount of ester-soluble substances is more found in caps than in stems. Water soluble substances are more extracted from P. squarrosa. Isopropyl alcohol extracts more substances from shiitake. Qualitative and quantitative analysis of neutral compounds, acids, and compounds of isopropanol extract was carried out by chromatography-mass spectrometry. Isopropyl alcohol mainly extracts disaccharides and sugar alcohols. It was revealed that the main sugar alcohols of L. edodes are mannitol and ribitol. Sugar alcohols content differs in different parts. Ribitol predominates in the stems. Shiitake caps contain mannitol and ribitol in equal amounts. Sugar alcohols are present in trace amounts in P. squarrosa, but trehalose (disaccharide) is the main component of the alcoholic extract. The compositions of fatty acids, sterols, carbohydrates and sugar alcohols in various parts of mushrooms were determined. Ergosterol predominates among sterols, while linoleic acid prevails among acids. Caps have a more diverse sterol composition. Both types of fungi contain polysaccharides consisting of glucose residues. It grows in P. squarrosa; mercury and cadmium accumulate in vivo. Wood-based shiitake grown in a greenhouse contains almost no mercury and cadmium, but contains iron. The amount of cadmium and mercury in the caps is greater than the stems. Metals are not extracted with isopropyl alcohol and are practically not extracted with hot water.
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Ikpeazu, V. O., S. A. U. Offiah, J. Chikezie, L. N. Chigbu, A. J. Ekenjoku, N. C. A. Chinyere i N. M. Igboh. "Lipid Profile and Reductive Enzyme Activities in Chronic Alcoholics in Aba Metropolis". American Journal of Health, Medicine and Nursing Practice 7, nr 13 (8.01.2023): 14–17. http://dx.doi.org/10.47672/ajhmn.1316.
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Purpose: Chronic alcohol consumption predisposes individuals to several disorders, though, such effect depends on its level of concentration in the blood overtime. To ascertain the effects of alcohol on various tissues and organs of the body, the study evaluated the plasma lipids and reductive enzymes in alcoholics in Aba Metropolis.
Methodology: A total of one hundred and fifty subjects comprising hundred alcoholics and fifty age marched non-alcoholics were included in the study. Subjects with chronic diseases or other health issues and subjects with intake of drugs like thiazides, beta blockers and steroids were excluded from the study while those who were regular drinkers met the inclusion criteria for the test group. Both the test group and control group resided within Aba Metropoli. The alcoholic subjects were grouped into moderate and heavy drinkers based on the amount of alcohols consumed per week. Serum was obtained from blood collected from the subjects by venipuncture was used to determine lipid profile and the reductive enzymes. The data obtained were analyzed using statistical package for social science (SPSS version 25) and analysis of variance (ANOVA). Significance level for the analysis was set at P-value equal to or less than 0.05 (P=<0.05).
Findings: There was a significant increase in the mean levels of TC, TG, LDL, GGT and LDH in heavy drinkers’ alcoholics when compared to those who consumed alcohol moderately and non-alcoholics (control). In moderate alcoholics, there was significant increase in HDL and decrease in LDL when compared with heavy alcoholics. However, the increase in the assayed parameters in alcoholics suggest that high alcoholic beverages may induce derangement in some biochemical parameters monitored.
Recommendation: The study recommend that health awareness to be carried out to inform the public and vulnerable individuals on the risk of chronic alcohol consumption which may predispose them to various health problems.
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Lemay, Christian T. Y., Derek F. J. Ceccarelli i Richard M. Epand. "Fusion of influenza to liposomes is not inhibited by aliphatic primary alcohols". Bioscience Reports 14, nr 1 (1.02.1994): 33–42. http://dx.doi.org/10.1007/bf01901636.
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Reports of the antiviral activity of aliphatic alcohols led us to investigate the effects of aliphatic alcohols, from 10 to 20 carbons in length, on the phase transition behaviour of model phospholipids and on the fusion of influenza to liposomes. Contrary to the effects of many other antiviral agents, we find that alcohols are potent promoters of the inverted hexagonal phase. However, we also find that aliphatic alcohols have little effect on influenza fusion to liposomes. Eicosanol is the only aliphatic alcohol tested which substantially increases in fusion of influenza virus. We also find that long chain alcohols display multi-component bilayer to hexagonal phase transitions at higher mole fractions. This suggests that eicosanol may be facilitating fusion by creating defects between alcohol-rich and alcohol-poor regions of the lipid bilayer.
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Ménassa, Pierre, i Camille Sandorfy. "Hydrogen bonding of alcohols with AOT in carbon tetrachloride: an infrared study". Canadian Journal of Chemistry 63, nr 12 (1.12.1985): 3367–70. http://dx.doi.org/10.1139/v85-554.
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The interaction of the inverted micelles of AOT (sodium di(2-ethylhexyl)sulfosuccinate) with different alcohols due to hydrogen bonding has been studied by means of infrared spectroscopy. Spectra of solutions of the alcohols with increasing concentrations of AOT showed a decrease in the intensity of the free OH stretching band. At the same time a new OH band due to a H-bonded alcohol-inverted micelle complex appears and its intensity increases as the intensity of the free band decreases. Calculated values of the equilibrium constants for the formation of the complexes n-alcohol–AOT, showed a decrease in alcohol–AOT association with the increase of the length of the aliphatic chains in the n-alcohols. Surprisingly, cholesterol behaved like a short chain while other cyclic alcohols like long chain alcohols.
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Surya, I., B. Siregar, M. Khatami, Sudibyo i H. P. S. Abdul Khalil. "Fatty alcohols as sustainable compatibilizer agents for the compound of natural rubber/silica: The curing, rubberiness and tensile strength behaviours". IOP Conference Series: Earth and Environmental Science 1352, nr 1 (1.05.2024): 012030. http://dx.doi.org/10.1088/1755-1315/1352/1/012030.
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Abstract Fatty alcohols are derived from palm oil production and, stearyl and lauryl alcohols are examples of them. The stearyl and lauryl alcohols have the potential to be used as rubber additives for the compounding and vulcanizing processes. These materials are relatively new as rubber additives and, they were added into silica-filled natural rubber (NR) compound. The aim of using them is to increase the grade of silica dispersion inside the NR matrix. Initially, the NR was filled by (precipitate) silica at 30 parts per hundred of NR, whilst the fatty alcohols were added into the silica-filled NR with variable concentrations from 1 to 4 phr, separately. The compounds of NR/silica/stearyl alcohol and NR/silica/lauryl alcohol have been vulcanised at 150 °C by implementing a semi-efficient rubber composition. From the vulcanization behaviour, it was observed that both fatty alcohols have the role of compatibilizer and plasticising agents for the compound of NR/silica. Those fatty alcohols decreased the viscousness but increased the curing rate index (CRI). The more concentration of fatty alcohols was supplied, the less viscousness and the higher the CRI. Those fatty alcohols also shifted the crosslinking level and tensile strength. It also observed that the break elongation or rubberiness has been shifted up. Tensile strength has been shifted to a maximal value with a 2 phr of stearyl alcohol or 3 phr of lauryl alcohol addition.
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Singh, Vishwanath, i Nagappa Badiger. "Study of effective atomic numbers and electron densities, kerma of alcohols, phantom and human organs, and tissues substitutes". Nuclear Technology and Radiation Protection 28, nr 2 (2013): 137–45. http://dx.doi.org/10.2298/ntrp1302137s.
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Effective atomic numbers (ZPIeff) and electron densities of eighteen alcohols such as wood alcohol, CH3OH; grain alcohol, C2H5OH; rubbing alcohol, C3H7OH; butanol, C4H9OH; amyl alcohol, C5H11OH; cetyl alcohol, C16H33OH; ethylene glycol, C2H4(OH)2; glycerin, C3H5(OH)3; PVA, C2H4O; erythritol, C4H6(OH)4; xylitol, C5H7(OH)5; sorbitol, C6H8(OH)6; volemitol, C7H9(OH)7; allyl alcohol, C3H5OH; geraniol, C10H17OH; propargyl alcohol, C3H3OH; inositol, C6H6(OH)6, and menthol, C10H19OH have been calculated in the photon energy region of 1 keV-100 GeV. The estimated values have been compared with experimental values wherever possible. The comparison of ZPIeff of the alcohols with water phantom and PMMA phantom indicate that the ethylene glycol, glycerin, and PVA are substitute for PMMA phantom and PVA is substitute of water phantom. ZPIeff of alcohols have also been compared with human organs and tissues. Ethylene glycol, glycerin and PVA, allyl alcohol, and wood alcohols are found tissue substitutes for most of human organs. Kerma which is the product of the energy fluence and mass energy-absorption coefficient, have been calculated in the energy region from 1 keV to 20 MeV for the alcohols. The results show the kerma is more or less independent of energy above 100 keV.
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Gonçalves, Reinaldo Simões, i Luciano Valmir das Chagas. "Estudos potenciométricos da adsorção de álcoois insaturados sobre o eletrodo de cobre em meio H2SO4 diluído". Ciência e Natura 11, nr 11 (11.12.1989): 55. http://dx.doi.org/10.5902/2179460x25532.
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Potentiometric studies show the interaction between the copper surface electrode and propanol alcohol (H3C-CH2-CH2OH), allyl alcohol (H2C=CH-CH2OH) and propargyl alcohol (HC≡C-CH2OH). From them, only allyl alcohol and propargyl alcohol change the value of the electrode potentials, when the organic compounds are added to the solutions. The potential shifts suggest a strong interaction, with a chemical and stable adsorption of the alcohols on the surfasse electrode. The electrode potentials change quickly in the presence of the alcohols and depend on the concentration that is added. The adsorption of the alcohols independs on the acid concentration of the solution but it depends on the dissolved oxygen concentration. The shifts of the electrode potentials are lower in aerated solutions than in deaerated solutions, with both alcohols. The potential-time curves at 65ºC shown that allyl alcohol adsorption is weaker at high temperatures. However, the propargyl alcohol adsorption independs on the temperature of the solutions.
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Cáceres-Alonso, Mercedes, Miguel Costas, Lina Andreoli-Ball i Donald Patterson. "Steric effects on the self-association of branched and cyclic alcohols in inert solvents. Apparent heat capacities of secondary and tertiary alcohols in hydrocarbons". Canadian Journal of Chemistry 66, nr 4 (1.04.1988): 989–98. http://dx.doi.org/10.1139/v88-165.
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Apparent heat capacities have been measured for fifteen branched and cyclic alcohols in dilute n-decane solution at 25 °C. The alcohols were 2-methyl-2-propanol, cyclohexanol, 3-methyl-3-pentanol, trans-, cis-, and mixed isomer 2-methylcyclohexanol, 1-methylcyclohexanol, 3-ethyl-3-pentanol, cyclooctanol, 3,7-dimethyl-1-octanol, 5-decanol, 4-propyl-4-heptanol, cyclododecanol, 5-butyl-5-nonanol, and 8-hexadecanol (in n-hexane). Excess heat capacities CpE throughout the concentration range were measured at 25 °C for: 1-hexanol + n-hexadecane (n-C16) and + 2,2,4,4,6,8,8-heptamethylnonane (br-C16), 4-propyl-4-heptanol, and 1-decanol + n-decane, 3-methyl-3-pentanol + n-C16 and + br-C16 and at 27 °C for cyclohexanol + n-C16 and + br-C16. Also, for 3-methyl-3-pentanol + n-decane CpE was measured at 10, 25, 40, and 50 °C. For a series of isomeric alcohols, the apparent molar heat capacities show a maximum against concentration which decreases and moves to higher alcohol concentration as the hydroxyl group on the alcohol becomes increasingly hindered, effectively reducing the alcohol self-association capabilities. This situation is also reflected by the heat capacities of the pure alcohols which increase strongly in magnitude in going from a linear 1-alcohol to an isomeric alcohol which has its hydroxyl group on a quaternary carbon atom. CpE of the mixtures are negative at low alcohol concentrations turning positive at increasingly higher alcohol concentrations as the steric hindrance on the hydroxyl group increases. Throughout most of the concentration range CpE for the branched or cyclic alcohols is considerably more positive than for the corresponding isomeric 1 -alcohol. For the highly hindered 3-methyl-3-pentanol CpE(T) passes through a maximum. All of the above behaviour is explained by the Treszczanowicz–Kehiaian model for self-associated liquids + inert solvents which has been applied to the present data. Equilibrium constants have been obtained for alcohol association and are sensitive to alcohol structure. At low alcohol concentrations, while for the linear 1-alcohols tetramers are the predominant species and dimer are almost absent, for the corresponding isomeric alcohols the concentration of tetramers is severely reduced and the lower species, i.e. trimers and dimers, are more important. For the highly hindered alcohols, monomers are the predominant species in dilute solution reflecting the decrease in self-association ability that steric hindrance of the hydroxyl group imposes on them.
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Egaña-Juricic, María Esperanza, Gastón Gutiérrez-Gamboa i Yerko Moreno-Simunovic. "Making wine in Pañul’s craft pottery vessels: a first approach in the study of the dynamic of alcoholic fermentation and wine volatile composition". Ciência e Técnica Vitivinícola 37, nr 1 (2022): 29–38. http://dx.doi.org/10.1051/ctv/ctv20223701029.
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Traditional winemaking in amphora-like clay vessels is one of the oldest known methods of wine production. Currently, some wine producers have readopted traditional winemaking methods to generate unique attributes that differentiate their products raising regional wine typicity. The aim of this research was to study the dynamic of alcoholic fermentation and volatile composition of ‘Carignan’ wines fermented into Pañul’s clay vessels and comparing them with the wines vinified into stainless-steel tanks. Density curve of the musts contained in the Pañul’s pottery vessels followed a similar trend than in the samples contained in the stainless-steel tanks. The temperatures of the must and the cap during alcoholic fermentation were lower in the Pañul’s pottery vessels than in the stainless-steel tanks in most of the evaluated days. Thus, clay vessels may provide temperature-regulating properties beneficing wine fermentation compared to stainless-steel tanks. Pañul’s clay vessels produced wines with higher terpenes, β-ionone and 2-phenylethyl alcohol content, and lower values of some individual higher alcohols, isoamyl acetate, lactones, and pH than the stainless-steel tanks. Therefore, the results suggest that Pañul’s pottery vessels favored increasing the terpene alcohols and other volatile compounds concentrations, in addition to decreasing certain higher alcohols and acetate esters contents such as benzyl alcohol and iso-amyl acetate. These outcomes may be of interest to ceramic producers and wine producers since they open a range of economic opportunities to diversify their products.
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Sharma, Kakali, Shiba Prasad Sharma i SujitChandra Lahiri. "Novel Method for Identification and Quantification of Methanol and Ethanol in Alcoholic Beverages by Gas Chromatography-Fourier Transform Infrared Spectroscopy and Horizontal Attenuated Total ReflectanceFourier Transform Infrared Spectroscopy". Journal of AOAC INTERNATIONAL 92, nr 2 (1.03.2009): 518–26. http://dx.doi.org/10.1093/jaoac/92.2.518.
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Abstract Numerous methods are being used to identify and quantify methanol and ethanol in alcoholic beverages, including country liquors. Some of the known methods are density and refractive index measurements, and spectrophotometric measurements using Schiff's reagent or chromatropic acid. Other advanced techniques involve head space gas chromatography (GC), GCflame ionization detection, high-performance liquid chromatography, enzymatic reactions, and biosensors. However, identification and quantification of methanol and ethanol in beverages can be accurately done using GC-Fourier transform infrared spectroscopy (FTIR) and horizontal attenuated total reflectance (HATR)-FTIR. Identification of alcohols is possible from library matching of the IR spectra obtained from GC-FTIR. In water, methanol and ethanol show a very strong peak for CO, stretching at 1015.3 and 1044.2 cm1, respectively. The strong absorption of vibrational stretching frequency of CO present in alcohols was used for quantification purposes. The absorptions of CO group frequency of alcohols in water mixtures were measured using HATR-FTIR with a zincselenide crystal. Samples were placed directly on the HATR crystal, with alcohol concentrations ranging from 0.2 to 50.0 (v/v). The plot of absorptions against concentrations of methanol and ethanol obeyed Beer's law (r2 0.9998 and 0.9987, respectively), from which alcohol in the mixtures was quantified. Propan-2-ol and n-butanol showed no interference. The method is validated from absorption measurements of known mixtures of standard ethanol in water. This is a simple, specific, rapid, accurate, and nondestructive method of identification and quantification of methanol and ethanol in mixtures. It can be used to ascertain methanol contamination in alcoholic beverages that can lead to death or methanol poisoning by alcohol consumption.
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Yan, Tongshuai, Zexiang Wang, Haoyang Zhou, Jiaojiao He i Shishui Zhou. "Effects of Four Critical Gene Deletions in Saccharomyces cerevisiae on Fusel Alcohols during Red Wine Fermentation". Fermentation 9, nr 4 (14.04.2023): 379. http://dx.doi.org/10.3390/fermentation9040379.
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Excessive fusel alcohols in red wine will bring an uncomfortable bitterness and generate an intoxicating effect, which affects the quality and attractivity of the red wine. In order to achieve better regulation of fusel alcohols in red wine, strains with LEU1 and PDC5 deletions were constructed, and seven engineered yeast strains based on THI3 and BAT2 deletions were applied to red wine fermentation to dissect the effects of four critical genes on fusel alcohols during wine fermentation. The fermentation results of these recombinant strains showed that the deletion of THI3 increased the contents of n-propanol, isobutanol, and isoamyl alcohol by 48.46%, 42.01%, and 7.84%, respectively; the deletion of BAT2 decreased isoamyl alcohol and isobutanol by 32.81% and 44.91%; the deletion of PDC5 and LEU1 decreased isoamyl alcohol by 40.21% and 68.28%, while increased isobutanol by 24.31% and 142%, respectively; the deletion of THI3 exerted a negative influence on the reduction of isoamyl alcohol caused by BAT2 or PDC5 deletion; the deletion of THI3 and PDC5 had a synergistic effect on the increase of isobutanol, while BAT2 and PDC5 deletion presented no additive property to the decrease of isoamyl alcohol. Hence, it is concluded that either BAT2, PDC5, or LEU1 deletion can effectively decrease fusel alcohols, especially isoamyl alcohol, which provides an important reference for the control of fusel alcohols in red wine.
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Lin, Claire Lin, Mikael Agerlin Petersen i Andrea Gottlieb. "Increasing Higher Alcohols and Acetates in Low-Alcohol Beer by Proteases". Molecules 28, nr 11 (29.05.2023): 4419. http://dx.doi.org/10.3390/molecules28114419.
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The market of non-alcoholic and low-alcohol beer has grown continuously thanks to the advocacy for healthy and responsible drinking. Non-alcoholic and low-alcohol products usually possess less higher alcohols and acetates and more aldehyde off-flavors due to the manufacturing processes. The employment of non-conventional yeasts partially mitigates this problem. In this study, we used proteases to optimize the wort amino acid profile for better aroma production during yeast fermentation. The design of experiments was applied to increase the leucine molar fraction, aiming to boost 3-methylbutan-1-ol and 3-methylbutyl acetate (banana-like aromas). This led to an increase from 7% to 11% leucine in wort after protease treatment. The aroma output in the subsequent fermentation, however, was yeast-dependent. An 87% increase of 3-methylbutan-1-ol and a 64% increase of 3-methylbutyl acetate were observed when Saccharomycodes ludwigii was used. When Pichia kluyveri was employed, higher alcohols and esters from valine and isoleucine were increased: 58% more of 2-methylpropyl acetate, 67% more of 2-methylbutan-1-ol, and 24% more of 2-methylbutyl acetate were observed. Conversely, 3-methylbutan-1-ol decreased by 58% and 3-methylbutyl acetate largely remained the same. Apart from these, the amounts of aldehyde intermediates were increased to a varying extent. The impact of such increases in aromas and off-flavors on the perception of low-alcohol beer remains to be evaluated by sensory analysis in future studies.
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Idarraga-Mora, Jaime A., Michael A. Lemelin, Steven T. Weinman i Scott M. Husson. "Effect of Short-Term Contact with C1–C4 Monohydric Alcohols on the Water Permeance of MPD-TMC Thin-Film Composite Reverse Osmosis Membranes". Membranes 9, nr 8 (26.07.2019): 92. http://dx.doi.org/10.3390/membranes9080092.
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In this paper, we discuss the effect of alcohol contact on the transport properties of thin-film composite reverse osmosis membranes. Five commercial membranes were studied to quantify the changes in water permeance and sodium chloride rejection from contact with five C1–C4 monohydric, linear alcohols. Water permeance generally increased without decreasing rejection after short-term contact. The extent of these changes depends on the membrane and alcohol used. Young′s modulus measurements showed decreased stiffness of the active layer after contacting the membranes with alcohol, suggesting plasticization. Data analysis using a dual-mode sorption model identified positive correlations of the initial water permeance, as well as the change in free energy of mixing between water and the alcohols, with the increase in water permeance after alcohol contact. We suggest that the mixing of water with the alcohols facilitates alcohol penetration into the active layer, likely by disrupting inter-chain hydrogen bonds, thus increasing the free volume for water permeation. Our studies provide a modeling framework to estimate the changes in transport properties after short-term contact with C1–C4 alcohols.
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Zhong, Hui, Zheng Fang, Bao Hua Zou, Xin Li i Kai Guo. "Studies on the Immobilized-Lipase-Catalyzed Esterification of Alkyl Oleates in Solvent-Free Systems". Advanced Materials Research 645 (styczeń 2013): 19–23. http://dx.doi.org/10.4028/www.scientific.net/amr.645.19.
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The esterification of oleic acid with alkyl alcohols in solv ent-free systems was catalyzed by an immobilized lipase from Candida sp . 99-125. The influence of several factors, including enzyme concentration, temperature, molar ratio between oleic acid and alkyl alcohols, and structure of alcohol was also investigated. The results indicated that the reactions catalyzed by lipase at 20 o C, in the presence of 3% (w/w) lipase, on the molar ratio of 1:1 between oleic acid and alcohols, afforded products in high yield. It showed high selectivity to primary and low selectivity to secondary alcohols and tertiary alcohols because of the sterically hindered effect. Methanol has certain toxicity on the activity of the lipase. The lipase from Candida sp. 99-125 was identified to be an effective catalyst in the esterification of alcohol and oleic acid at low temperature.
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Man, Adrian, Andrei Şerban Gâz, Anca Delia Mare i Lavinia Berţa. "Effects of low-molecular weight alcohols on bacterial viability". Revista Romana de Medicina de Laborator 25, nr 4 (26.10.2017): 335–43. http://dx.doi.org/10.1515/rrlm-2017-0028.
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Abstract Alcohol based solutions are among the most convenient and wide spread aid in the prevention of nosocomial infections. The current study followed the efficacy of several types and isomers of alcohols on different bacterial species. Seven alcohols (ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl alcohol, and ethylene glycol) were used to evaluate their minimal inhibitory and bactericidal effects by microdilution method on bacteria that express many phenotypical characteristics: different cell-wall structure (Gram positive/negative bacteria), capsule production (Klebsiella pneumoniae), antibiotic resistance (MRSA vs MSSA) or high environmental adaptability (Pseudomonas aeruginosa). Results: The best inhibitory effect was noticed for n-propyl, followed by iso-propyl, n-butyl, and iso-butyl alcohols with equal values. Ethylene glycol was the most inefficient alcohol on all bacteria. In K. pneumoniae and P. aeruginosa, the bactericidal concentrations were higher than the inhibitory one, and to a level similar to that encountered for most of the Gram-positive bacteria. Among Gram-positive cocci, E. faecalis presented the lowest susceptibility to alcohols. Conclusions: All alcohols presented good effect on bacteria, even in low concentrations. Compared to ethanol as standard, there are better alternatives that can be used as antimicrobials, namely longer-chain alcohols such as propyl or butyric alcohols and their iso- isomers. Ethylene glycol should be avoided, due to its toxicity hazard and low antimicrobial efficacy. Bacterial phenotype (highly adaptable bacteria, biofilm formation) and structure (cell wall structure, presence of capsule) may drastically affect the responsiveness to the antimicrobial activity of alcohols, leading to higher bactericidal than inhibitory concentrations.
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Wang, Ya-Ping, Xiao-Qing Wei, Xue-Wu Guo i Dong-Guang Xiao. "Effect of the Deletion of Genes Related to Amino Acid Metabolism on the Production of Higher Alcohols by Saccharomyces cerevisiae". BioMed Research International 2020 (5.11.2020): 1–12. http://dx.doi.org/10.1155/2020/6802512.
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The higher alcohols produced by Saccharomyces cerevisiae exert remarkable influence on the taste and flavour of Chinese Baijiu. In order to study the regulation mechanism of amino acid metabolism genes on higher alcohol production, eight recombinant strains with amino acid metabolism gene deletion were constructed. The growth, fermentation performance, higher alcohol production, and expression level of genes in recombinant and original α5 strains were determined. Results displayed that the total higher alcohol concentration in α5ΔGDH1 strain decreased by 27.31% to 348.68 mg/L compared with that of α5. The total content of higher alcohols in α5ΔCAN1 and α5ΔGAT1 strains increased by 211.44% and 28.36% to 1493.96 and 615.73 mg/L, respectively, compared with that of α5. This study is the first to report that the CAN1 and GAT1 genes have great influence on the generation of higher alcohols. The results demonstrated that amino acid metabolism plays a substantial role in the metabolism of higher alcohols by S. cerevisiae. Interestingly, we also found that gene knockout downregulated the expression levels of the knocked out gene and other genes in the recombinant strain and thus affected the formation of higher alcohols by S. cerevisiae. This study provides worthy insights for comprehending the metabolic mechanism of higher alcohols in S. cerevisiae for Baijiu fermentation.
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Cantoral, Jesús Manuel, Antonio Florido-Barba, María Fernanda Lopez-Molina i Gustavo Cordero-Bueso. "Adaptación y desarrollo del velo de flor en vinos “sobretablas” de la D.O. Jerez-Xèrés-Sherry fortificados con alcoholes no vínicos". BIO Web of Conferences 56 (2023): 02029. http://dx.doi.org/10.1051/bioconf/20235602029.
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The EC 2019/187 shows the rules for the usage of ethyl alcohols to fortify wines. These must be obtained from products derived from agriculture and the use of alcohols of mineral or chemical origin is not authorized. The ethyl alcohols authorized for the fortification in the D.O. Sherry have wine origin. But, there are other alcohols that could be equally productive and at a lower economic cost, such as beet or sugar cane alcohol. The effect that different types of ethyl alcohols may have on the yeasts of flor remains unknown. Our goal was to analyze the effects of other alcohols (beet, sugar cane, etc.) on the development of the veil of flor. In this way, the yeasts that constitute the veil of flor of Fino wines were isolated and identified by microbiological techniques and characterized by molecular tools and by biochemical and microbiological tests such as cellular hydrophobicity, flocculation, acetic acid production, etc. Then, base wines were fortified with different distilled alcohols, such as malt brandy, tequila, among others. Biological aging under the veil of flor was monitored to later determine the volatile fractions. Alcohol from sugar cane could be a promising alternative to fortify Fino wines.
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Alcarde, André Ricardo, Paula Araújo de Souza i André Eduardo de Souza Belluco. "Volatilization kinetics of secondary compounds from sugarcane spirits during double distillation in rectifying still". Scientia Agricola 67, nr 3 (2010): 280–86. http://dx.doi.org/10.1590/s0103-90162010000300005.
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The qualitative variation of secondary components plays a key role in the aroma and taste of the sugarcane spirit. The objective of this work was to study the volatilization kinetics of secondary components of sugarcane spirits during double distillation process in a rectifying still to verify the cutoff point in ethanol between "head" and "tail" fractions. Fermented sugarcane juice was distilled in rectifying still according to the methodology used for whisky production. Both distillates from first and second distillations were collected in fractions of 500 mL and analyzed for the concentrations of ethanol, copper, volatile acidity, furfural and hydroxymethylfurfural, aldehydes, esters, methanol and higher alcohols. In the first distillation, aldehydes and esters were distilled at the beginning of the distillation, while acetic acid was distilled at the end of the distillation. Methanol was found in the fractions up to almost half of the first distillation. Higher alcohols were distilled during the whole first distillation, but with greater intensity up to the alcoholic degree of 40% v v-1 of the distillate. During the second distillation, aldehydes, esters and methanol were distilled in the first distillate fractions, being collected mainly at alcohol concentrations above 80% v v-1. Acetic acid was distilled in the final distillate fractions, with concentrations in alcohol content below 20% v v-1. Higher alcohols followed a distillation kinetics pattern similar to ethanol, being collected mainly at alcoholic concentrations above 60% v v-1 of the distillate. The presence of copper, furfural and hydroxymethylfurfural was not detected in any fraction of the distillates of the first and second distillation.
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Sohilait, Hanoch J. "OXIDATION OF BENZYLIC SECONDARY ALCOHOL WITH PYRIDINIUM CHLOROCHROMATE-ALUMINA (PCC-Al2O3)". Indonesian Journal of Chemistry 8, nr 1 (17.06.2010): 91–93. http://dx.doi.org/10.22146/ijc.21658.
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In these studies, Pyridinium chlorochromate-Alumina was used for oxidation of secondary alcohols (safryl alcohol and methyleugenyl alcohol) to ketone. The oxidation of safryl alcohol with PCC-Al2O3 followed by purification by potassium bisulfite yields safryl ketone (62,92%). The oxidation of methyleugenyl alcohol with PCC-Al2O3, followed by purification by potassium bisulfite yields methyleugenyl ketone (68,04%). The elucidation of these products was analyzed by FTIR, 1H-NMR and MS. Keywords : PCC-alumina, secondary alcohols, ketone
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Pantazopoulous, Panagiotis E., i Michael T. Madigan. "Primary alcohols and di-alcohols as growth substrates for the purple nonsulfur bacteriumRhodobacter capsulatus". Canadian Journal of Microbiology 46, nr 12 (1.12.2000): 1166–70. http://dx.doi.org/10.1139/w00-104.
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Growth experiments were performed with the purple nonsulfur bacterium Rhodobacter capsulatus to test its ability to use aliphatic, methyl-substituted, and unsaturated alcohols, as well as di-alcohols, as carbon sources for growth. Both phototrophic and chemotrophic growth was observed on a wide variety of such alcohols. By contrast, secondary or tertiary alcohols, or primary alcohols containing an ethyl or propyl substituent, did not support growth. In addition, preculture history and serial subculturing were found to be important factors for obtaining reliable growth of R. capsulatus on alcohols. Collectively, these results suggest that the carbon nutritional diversity of Rhodobacter capsulatus is even greater than previously suspected and that besides metabolizing organic acids and fatty acids in nature, this species may also be a major consumer of alcohols.Key words: purple nonsulfur bacteria, Rhodobacter capsulatus, alcohol metabolism, primary alcohols, di-alcohols.
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Huffer, Sarah, Melinda E. Clark, Jonathan C. Ning, Harvey W. Blanch i Douglas S. Clark. "Role of Alcohols in Growth, Lipid Composition, and Membrane Fluidity of Yeasts, Bacteria, and Archaea". Applied and Environmental Microbiology 77, nr 18 (22.07.2011): 6400–6408. http://dx.doi.org/10.1128/aem.00694-11.
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ABSTRACTIncreased membrane fluidity, which causes cofactor leakage and loss of membrane potential, has long been documented as a cause for decreased cell growth during exposure to ethanol, butanol, and other alcohols. Reinforcement of the membrane with more complex lipid components is thus thought to be beneficial for the generation of more tolerant organisms. In this study, organisms with more complex membranes, namely, archaea, did not maintain high growth rates upon exposure to alcohols, indicating that more complex lipids do not necessarily fortify the membrane against the fluidizing effects of alcohols. In the presence of alcohols, shifts in lipid composition to more saturated and unbranched lipids were observed in most of the organisms tested, including archaea, yeasts, and bacteria. However, these shifts did not always result in a decrease in membrane fluidity or in greater tolerance of the organism to alcohol exposure. In general, organisms tolerating the highest concentrations of alcohols maintained membrane fluidity after alcohol exposure, whereas organisms that increased membrane rigidity were less tolerant. Altered lipid composition was a common response to alcohol exposure, with the most tolerant organisms maintaining a modestly fluid membrane. Our results demonstrate that increased membrane fluidity is not the sole cause of growth inhibition and that alcohols may also denature proteins within the membrane and cytosol, adversely affecting metabolism and decreasing cell growth.
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Manjunath, M. S., P. Sivagurunathan i J. Sannappa. "Studies of Hydrogen Bonding BetweenN, N-Dimethylacetamide and Primary Alcohols". E-Journal of Chemistry 6, s1 (2009): S143—S146. http://dx.doi.org/10.1155/2009/120362.
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Hydrogen bonding betweenN, N-dimethylacetamide (DMA) and alcohols has been studied in carbon tetrachloride solution by an X-band Microwave bench at 936GHz. The dielectric relaxation time (τ) of the binary system are obtained by both Higasi's method and Gopalakrishna method. The most likely association complex between alcohol and DMA is 1:1 stoichiometric complex through the hydroxyl group of the alcohol and the carbonyl group of amide. The results show that the interaction between alcohols and amides is 1:1 complex through the free hydroxyl group of the alcohol and the carbonyl group of amide and the alkyl chain-length of both the alcohols and amide plays an important role in the determination of the strength of hydrogen bond (O-H: C=O) formed and suggests that the proton donating ability of alcohols is in the order: 1-propanol < 1-butanol < 1-pentanol and the accepting ability of DMA.
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Carlson, Charles G., Judith E. Hall, Yan Y. Huang, Sirpa Kotila, Arvi Rauk i Donald F. Tavares. "The preparation of esters of formic acid using boron oxide". Canadian Journal of Chemistry 65, nr 10 (1.10.1987): 2461–63. http://dx.doi.org/10.1139/v87-411.
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Boron oxide has been found to act as an efficient reagent in the preparation of a number of formate esters by the direct esterification of formic acid with the alcohol. The reaction is most appropriate for primary and secondary alcohols, including unsaturated alcohols. The formate ester so produced is free of contamination by unreacted alcohol.
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Scully, Sean Michael, Aaron E. Brown, Yannick Mueller-Hilger, Andrew B. Ross i Jóhann Örlygsson. "Influence of Culture Conditions on the Bioreduction of Organic Acids to Alcohols by Thermoanaerobacter pseudoethanolicus". Microorganisms 9, nr 1 (12.01.2021): 162. http://dx.doi.org/10.3390/microorganisms9010162.
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Thermoanaerobacter species have recently been observed to reduce carboxylic acids to their corresponding alcohols. The present investigation shows that Thermoanaerobacter pseudoethanolicus converts C2–C6 short-chain fatty acids (SCFAs) to their corresponding alcohols in the presence of glucose. The conversion yields varied from 21% of 3-methyl-1-butyrate to 57.9% of 1-pentanoate being converted to their corresponding alcohols. Slightly acidic culture conditions (pH 6.5) was optimal for the reduction. By increasing the initial glucose concentration, an increase in the conversion of SCFAs reduced to their corresponding alcohols was observed. Inhibitory experiments on C2–C8 alcohols showed that C4 and higher alcohols are inhibitory to T. pseudoethanolicus suggesting that other culture modes may be necessary to improve the amount of fatty acids reduced to the analogous alcohol. The reduction of SCFAs to their corresponding alcohols was further demonstrated using 13C-labelled fatty acids and the conversion was followed kinetically. Finally, increased activity of alcohol dehydrogenase (ADH) and aldehyde oxidation activity was observed in cultures of T. pseudoethanolicus grown on glucose as compared to glucose supplemented with either 3-methyl-1-butyrate or pentanoate, using both NADH and NADPH as cofactors, although the presence of the latter showed higher ADH and aldehyde oxidoreductase (ALDH) activity.
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Phan, Thanh Binh, i Herbert Mayr. "Comparison of the nucleophilicities of alcohols and alkoxides". Canadian Journal of Chemistry 83, nr 9 (1.09.2005): 1554–60. http://dx.doi.org/10.1139/v05-170.
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The kinetics of the reactions of benzhydrylium ions with some alcohols and alkoxides dissolved in the corresponding alcohols were photometrically investigated. Using the correlation equation log k (20 °C) = s(E + N), the N and s parameters of methoxide, ethoxide, n-propoxide, and isopropoxide in alcoholacetonitrile (91:9, v/v) were determined. The cosolvent acetonitrile has only a little influence on the rate constants of the reactions of alcohols and alkoxides. The order of N values (OH << MeO < EtO < n-PrO < i-PrO) shows that alkoxides differ only moderately in reactivity but are considerably more nucleophilic than hydroxide. As a consequence, the nucleophilic reactivity of a 0.5 mmol/L aqueous hydroxide solution increases by a factor of 13 when 10% (v/v) methanol is added. In 110 mmol/L alkoxide solutions in alcohols, weak electrophiles react considerably faster with alkoxides than with the corresponding alcohols. With increasing electrophilicity, the preference for alkoxides decreases, and electrophiles of 3 < E < 3 react with alkoxides (110 mmol/L) and alcohols with comparable rates. Stronger electrophiles will react with alcohols exclusively when alkoxides are present in concentrations ≤10 mmol/L. Key words: kinetics, alcohol, alkoxide, linear free energy relationship, nucleophilicity.<
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Liltorp, Karin, Peter Westh i Yoshikata Koga. "Thermodynamic properties of water in the water-poor region of binary water + alcohol mixtures". Canadian Journal of Chemistry 83, nr 5 (1.05.2005): 420–29. http://dx.doi.org/10.1139/v05-050.
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In our previous thermodynamic studies, we suggested that alcohol molecules in water-poor water + alcohol mixtures exist as alcohol clusters in a form similar to the pure alcohols. Here, we use calorimetry and densitometry to investigate how H2O interacts with alcohol clusters in water-poor binary aqueous mixtures of 12 different alcohols. The composition dependence of the measured excess partial molar enthalpy and volume of water (HEW and VEW), along with entropy data calculated from HEW and literature data for excess chemical potentials, showed that in water-poor solutions of small alcohols such as methanol, ethanol, and 1-propanol, mutual waterwater interactions are endothermic, but entropically favorable. Conversely, in long-chain solvents such as 1-octanol and 1-decanol, the interaction is exothermic and entropically unfavorable. We suggest that these observations reflect wateralcohol hydrogen bonding in short-chain solvents and water clustering with more hydrogen bonding than in pure water or "dewetting" in mixtures of the longer alcohols, respectively. The composition dependence of HEW was also used to locate anomalies that specify the boundary between the mixing schemes characterizing the intermediate and the water-poor regions of alcohol + water mixtures.Key words: aqueous alkane-mono-ols, excess partial molar enthalpy, entropy and volume, mixing schemes.
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Indrati, Retno, i Yoshiyuki Ohta. "Purification and properties of alcohol dehydrogenase from a mutant strain of Candida guilliermondii deficient in one form of the enzyme". Canadian Journal of Microbiology 38, nr 9 (1.09.1992): 953–57. http://dx.doi.org/10.1139/m92-153.
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Alcohol dehydrogenase (ADH1) was purified from Candida guilliermondii strain B10-05 to homogeneity, using affinity chromatography on triazine dyes and gel filtration. The enzyme was tetrameric, with a subunit molecular weight of 38 000. The purified enzyme oxidized primary and secondary alcohols, although it preferred primary alcohols. Its activity toward secondary alcohols was better than those of other yeast ADH; however, the enzyme was less sensitive toward inhibitors. Kinetic studies indicated that C. guilliermondii ADH1 oxidized ethanol by an ordered bi–bi mechanism, with NAD as the first substrate fixed. Key words: Candida guilliermondii, alcohol dehydrogenase, ADH1, tetrameric.
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Sohilait, Hanoch J., Hardjono Sastrohamidjojo i Sabirin Matsjeh. "SYNTHESIS OF SECONDARY ALCOHOL COMPOUNDS FROM SAFROLE AND METHYLEUGENOL". Indonesian Journal of Chemistry 3, nr 3 (9.06.2010): 176–78. http://dx.doi.org/10.22146/ijc.21885.
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Synthesis of secondary alcohols compound from safrole and methyleugenol has been achieved through conversion of allyl group to alcohol.The reaction of safrole and methyleugenol with mercuric acetate in aqueous tetrahydrofuran, followed by in situ reduction of the mercurial intermediate by alkaline sodium borohydride produced secondary alcohol namely safryl alcohol (71.25%) and methyleugenil alcohol (65.56%). The structure elucidation of these products were analyzed by FTIR, 1H-NMR, 13C-NMR and MS. Keywords: Secondary alcohols; safrole; methyleugenol
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Luo, Hui Bo, Yi Wang, Cai Hong Wang, Xiao Dong Yang i Dan Yu Li. "Metabolic Control of Higher Alcohols Producing by Saccharomyces cerevisia in Mulberry Wine Brewing". Advanced Materials Research 781-784 (wrzesień 2013): 1861–65. http://dx.doi.org/10.4028/www.scientific.net/amr.781-784.1861.
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Aiming at the problem that higher alcohols has too high level in mulberry wine, the factors which have impact on the production of higher alcohols during alcoholic fermentation in mulberry wine was studied, including pH, fermentation temperature, inoculation, SO2, the amount of nitrogen. The results showed that: higher alcohols formation was significantly reduced when increase inoculation or lower the pH and fermentation temperature. Added nitrogen lead to the increasing formation of higher alcohols. With the increased levels of SO2, higher alcohols formation increased in a certain range. The higher alcohols formation was inhibited when the SO2content up to 200.00mg/L.
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Vogt, Thomas, i Paul-Gerhard Gülz. "Epicuticular Leaf Wax of Cistus albanicus, Cistaceae". Zeitschrift für Naturforschung C 42, nr 1-2 (1.02.1987): 157–58. http://dx.doi.org/10.1515/znc-1987-1-226.
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The epicuticular wax of Cistus albanicus was investigated. Homologous series of alkanes, wax esters, alcohols and long chain fatty acids were identified. The alcohol fraction consisted of primary and most probably of secondary alcohols.
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Gotsulskyi, V. Ya, N. P. Malomuzh i V. E. Chechko. "Extraordinary Properties of Alcohols from the Homologous Series of Methanol". Ukrainian Journal of Physics 65, nr 1 (3.02.2020): 31. http://dx.doi.org/10.15407/ujpe65.1.31.
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Non-trivial properties of thermodynamic quantities such as the density, the critical and triple point temperatures, and their ratio, as well as the optical and dielectric properties, have been analyzed for primary alcohols from the methanol series. The aim is to reveal relationships among their values measured at the same temperatures for alcohols with different ordinal numbers m’s in the methanol series. It is shown that the non-monotonic character of the temperature dependences of alcohol densities is associated with methanol rather than ethanol, as may seem at first glance. The critical temperature of methanol also deviates from the quasilinear dependence of the critical alcohol temperatures on m. With the growing m, the ratio between the critical and triple-point temperatures for alcohols is shown to tend to the corresponding value for water. Simple linear dependences of the electronic and effective static polarizabilities of alcohol molecules on m are established. The transverse and longitudinal components of the polarizability tensor for alcohol molecules are found. The dipole moments of the closest neighbor molecules in the alcohols are proved to anticorrelate, i.e. to orient in opposite directions.
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Balanyuk, V., N. Kozyar i A. Kravchenko. "PROSPECTS AEROSOL SUBLAYER QUENCHING OF ALCOHOLS". Fire Safety 35 (26.02.2020): 5–9. http://dx.doi.org/10.32447/20786662.35.2019.01.
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The study addresses the problems of gas alcohols and describes the factors that make the fire extinguishing efficiency of aerosol refractory gas alcohol. To date, alcohol storage facilities are not sufficiently protected, as evidenced by the fires that occur on them. The actuality of the work is emphasized by the fact that the fires at the objects for the storage and processing of alcohols and their mixtures are characterized by a high velocity of flame propagation up to 10 m / s, and the achievement of high values of temperatures inside the volume in the first minutes, the possibility of explosions of both gas and air mixtures and pressure vessels subjected to heat. The article theoretically describes the quenching process and shows that such quenching must be effective at the expense of synergies between the factors of influence. The paper presents the analysis and theoretical generalizations of the process of extinguishing alcohols and alcohol-containing liquids. The disadvantages of quenching alcohols and alcohol-containing liquids by foam agents are indicated. The process of quenching by inert gas is considered and the method of sublayer quenching of alcohols by extinguishing aerosol is proposed. It is established that sublayer quenching by aerosol occurs in 3 stages. At the first stage - at the exit of the aerosol there will be mixing of the liquid, reducing the surface temperature of the combustible liquid and equalizing the temperature on its height the column of the liquid. At the second stage - after the aerosol exits the fluid layer and enters the surface, the concentrations of the components of the combustion mixture are reduced, the radiation shielded from the combustion zone and its influence on the surface of the combustible liquid and the sides of the tank are reduced. At the third stage, when the aerosol enters the combustion zone, the following extinguishing factors are realized: inhibition, phlegmatization, cooling, and partially change of physical parameters, such as increase in pressure and volume. The combination of these factors at the same time provides a significant reduction in the time of quenching of alcohol compared to conventional methods of quenching. By the result of the analysis of the process of extinguishing alcohol and alcohol-containing mixtures by different extinguishing agents it has been theoretically substantiated and experimentally confirmed the high efficiency of sublayer quenching by gas-aerosol mixtures of alcohols and their mixtures. The advantages of this type of extinguishing are the low cost of the fire extinguishing system, the considerable period of operation, the high extinguishing efficiency and ease of maintenance and use.
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Loskutnikova, E. I., A. U. Gil, I. N. Alekhin i R. A. Khalfin. "Analysis of morbidity with poisonings with ethanol and surrogate alcohols in irkutsk region between 2010 and 2017". Sechenov Medical Journal 10, nr 2 (30.06.2019): 36–44. http://dx.doi.org/10.47093/22187332.2019.2.36-44.
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Aim. Poisonings with ethanol and surrogate alcohols are preventable causes of morbidity and mortality posing a serious threat to population health. The aim of the study was to analyze the dynamics of the incidence of acute poisoning with ethyl and surrogate alcohols in the Irkutsk region for the period from 2010 to 2017, and to discuss it in the context of the regional and federal policy aimed at regulation of the alcohol - containing products. Materials and methods. The data of the statistical reporting form No. 12-15 “Information on the results of toxicological monitoring” in the Irkutsk region for the period from 2010 to 2017, the data of the Federal State Statistics Service RosStat on the incidence of acute chemical poisoning, and on incidence of acute poisoning with ethyl alcohol and surrogate alcohols were analyzed. Subsequent interpretation of the results in the context of the regional and federal alcohol control policy has been performed. Results. In the Irkutsk region, during the analyzed period of time there was observed a high incidence of acute poisonings with ethanol and surrogate alcohols with territorial differences within the region, and with positive dynamics of reduction of incidence by 38.7% in 2017 in comparison to 2010. Poisonings with ethanol occupy a leading place in the structure of the incidence in comparison with poisoning with other alcohols. The Irkutsk region was ranked 9th among all other subjects of the Russian Federation in 2017 by level of morbidity with alcohol poisonings. Among all cases of poisonings the proportion of the adult working age population was 89.1%, males - 77%, and unemployed population - 57.8%, which suggests that these categories of population are under the highest risk of acute poisoning with ethanol and surrogate alcohols. Conclusion. Strengthening control over the illegal distribution of ethyl alcohol and alcohol - containing products, especially in the territories situated along the Federal highways is seen as a priority area for action. Control of distribution of alcohols between 2010 and 2017 on the territory of the Irkutsk region allowed reducing incidence of poisonings by 38.7%. To maintain the positive dynamics of reducing morbidity and mortality from acute poisoning of alcohol etiology, to preserve the labor potential of the population of the Irkutsk region, it is necessary to further strengthen and reinforce control measures at the regional level.
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Kalichkina, L. E., A. A. Bakibaev i V. S. Malkov. "Spectral study of thione-thiol tautomerization of thiourea in aqueous alcohol solution". Bulletin of the Karaganda University. "Chemistry" series 99, nr 3 (30.09.2020): 66–71. http://dx.doi.org/10.31489/2020ch3/66-71.
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In this work we studied the equilibrium of thione–thiol tautomerization by Raman and UV spectroscopies. This type of tautomerization influences on the course and direction of the reaction between thiourea and other organic compounds. The studies were carried out in water and aqueous alcohol medium. Мethanol, ethanol, propanol-1 and propanol-2 were used as alcohols. Hydrochloric acid was used to protonate thiourea in water and aqueous alcoholic solutions. UV spectroscopy made it possible to establish the tautomer ratio in water and aqueous alcohol solutions as the ratio of the intensities of absorption bands at 236 and 200 nm. There is an increase in the content of the thiol form and a decrease of the thione form observed in the row water-methanol-ethanol-propanol-isopropyl alcohol. The addition of hydrochloric acid to the thiourea water or aqueous alcohol solutions leads to the increase of the thione form and to the decrease of the thiol form in the composition. The thione form of thiourea can be determine by Raman spectra of –C=S group. The thiol form of thiourea is difficult to detect by Raman spectroscopy due to the overlap of the –S–H bond absorption band with alcohols absorption bands.
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Miyamoto, Takaki, Eiji Minami i Haruo Kawamoto. "Gasification of Lower Monohydric Alcohols by Solution Plasma Treatment and Its Reaction Mechanism". Hydrogen 4, nr 2 (16.06.2023): 373–88. http://dx.doi.org/10.3390/hydrogen4020026.
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Solution plasma is a gas-phase discharge in the vapor bubbles in a solution and has the potential to efficiently produce H2 by decomposing aqueous alcohols. However, the mechanism of alcohol decomposition in solution plasma remains unclear. In this study, lower monohydric alcohols (methanol and ethanol, as well as 1- and 2-propanol) were treated in solution plasma, and in this paper, the gasification mechanism is discussed. The gases produced from these alcohols were mainly H2 and CO, with small ratios of C1–C3 hydrocarbons. Thus, the O/C ratio in the product gas was close to 1 for all alcohols, and most of the C atoms in the alcohols were bonded to O atoms. This excess of O atoms could have only come from water, suggesting a strong contribution of OH radicals from water for gasification. However, the C1–C3 hydrocarbons were produced solely by the decomposition of the alcohol. For both decomposition routes, possible reaction pathways are proposed that are consistent with the experimental facts such as the composition of the product gas and the intermediates detected.
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Rahman, Maizar, Widjoseno Kaslan, Atung Kontawa i Retno Ambarwati. "RESPONSES OF GASOLINES TO METHANOL/TBA". Scientific Contributions Oil and Gas 11, nr 1 (13.04.2022): 16–19. http://dx.doi.org/10.29017/scog.11.1.1143.
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Low level alcohol-gasoline blends with normally under 10 vol% of alcohols are intended for use in the existing curs. Because the alcohols have differents properties than hydrocarbon components, their impact on critical gasoline properties have to be understood. This article discussed the research results on the properties of MEOH TBA (50/50) gasoline mixture at different alcohol levels using base fuels from different local refineries.
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Fonte, Aníbal. "Complexities in the Investigation of Alcohol Consumption in the Elderly: Challenges and Perspectives". International Journal of Psychology and Neuroscience 9, nr 2 (31.08.2023): 65–69. http://dx.doi.org/10.56769/ijpn09206.
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Abstract Alcohol, primarily represented by the molecule CH3CH2OH, is a key component in various alcoholic beverages. These beverages encompass a wide range of ingredients, including aliphatic alcohols, organic acids, esters, aldehydes, ketones, phenols, sugars, tannins, flavonoids, natural flavors, and water. The global alcohol market has immense potential, with over half of the population in certain regions already consuming alcoholic beverages. Despite the aging global population, there is a lack of comprehensive studies on alcohol use among the elderly, who face unique challenges related to aging. Several factors contribute to this research gap, including a historical focus on younger age groups, underreporting and underestimation of the issue, stigma, participation barriers, lack of recognition, and the complexity of factors involved. However, as the elderly population continues to grow, interest in this area is likely to increase. Additionally, the aging demographic represents a significant economic market, and the "elderly empowerment" movement may influence changing consumption patterns among older individuals, making continued research into alcohol consumption in this demographic essential. Keywords: Alcohol, Elderly, Aging, Alcohol consumption, CH3CH2OH, alcoholic beverages, elder.
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Gong, Jiani, Kaixin Yao, Qihan Sun, Yujia Sun, Lijie Sun, Changyao Liu, Bo Xu, Jiajing Tan, Li Zhao i Baocai Xu. "Interfacial Composition of Surfactant Aggregates in the Presence of Fragrance: A Chemical Trapping Study". Molecules 27, nr 14 (6.07.2022): 4333. http://dx.doi.org/10.3390/molecules27144333.
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In recent years, there has been increasing interest in daily-use chemical products providing a pleasant scent. The added fragrance molecules may induce microstructural transitions of surfactant aggregates, which further affect the physical and chemical properties of the products. Here, the effects of four types of aromatic alcohols (cinnamyl alcohol, phenyl ethanol, phenyl methanol and anisyl alcohol) on cetyltrimethylammonium bromide (CTAB)/KBr aggregates were studied. The combined results from rheology, dynamic light scattering, and transmission electron microscopy measurements showed that cinnamyl alcohol induced significant micellar growth, while increases in micellar growth were less obvious for the other aromatic alcohols. The changes in the interfacial molarities of water, aromatic alcohol, and bromide ions during such transitions were studied using the chemical trapping method. Transitions resulting from added cinnamyl alcohol were accompanied by significant declines in interfacial water and bromide ion molarities, and a rise in interfacial alcohol molarity. The marked decrease in interfacial water molarity was not observed in previous studies of the octanol induced formation of wormlike micelles and vesicles, indicating that a different mechanism was presented in the current system. Nuclear magnetic resonance investigation showed that π–π stacking between cinnamyl alcohols, but not cation–π interactions between alcohols and CTAB headgroups, facilitated the tight packing of alcohol molecules in CTAB aggregates and the repulsion of water from the interfacial region. The current study may provide a theoretical basis for the morphological regulation of surfactant aggregates in the presence of additives.
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Peña, Laura F., Enol López, Ángel Sánchez-González i Asunción Barbero. "Diastereoselective Synthesis of cis-2,6-Disubstituted Dihydropyrane Derivatives through a Competitive Silyl-Prins Cyclization versus Alternative Reaction Pathways". Molecules 28, nr 7 (30.03.2023): 3080. http://dx.doi.org/10.3390/molecules28073080.
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A convenient regioselective synthesis of allyl- and vinylsilyl alcohols, from a common precursor, was described, by selecting the appropriate reaction conditions. Allyl- and vinylsilyl alcohols were tested in silyl-Prins cyclizations for the preparation of disubstituted oxygenated heterocycles in a one-pot sequential reaction. The methodology was sensitive to the structure of the starting alkenylsilyl alcohol and reaction conditions, with competitive pathways observed (particularly for allylsilyl alcohols), such as Peterson elimination and oxonia-Cope reactions. However, the use of vinylsilyl alcohols allowed the preparation of differently disubstituted cis-2,6-dihydropyrans in moderate to good yields. Computational studies support the proposed mechanism.
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Rossi, Pier Francesco, i Paola Rossi. "Heats of Adsorption of Aliphatic Alcohols on α-Al2O3 at 25–200°C. II. Variations with Chain Length". Adsorption Science & Technology 15, nr 1 (luty 1997): 69–77. http://dx.doi.org/10.1177/026361749701500107.
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The adsorption of the first five members of the aliphatic alcohol series on α-Al2O3 has been studied at 25–200°C by means of a heat-flow Calvet microcalorimeter (moderately high temperature). At very low coverage and at 25°C, the values of the differential heats of adsorption of the different alcohols were very high (250–200 kJ/mol) and were apparently independent of the chain length. However, at average coverage, the chain length of the alcohol began to influence both the values and the trends in the differential heats of adsorption of the various alcohols on α-Al2O3. Finally, at high coverage, it was found that the incorporation of each additional –CH2–group in the homologous series led to a decrease in both the integral heat of adsorption and the amount of alcohol adsorbed according to the series MeOH > EtOH > 1-PrOH > 1-BuOH > 1-PeOH. Increasing the temperature led to an increasing dependence of the differential heat on the chain length of the alcohol. In addition, from measurements of the thermokinetic parameters for the heat emission peaks for the adsorbed alcohols, it has been deduced that all five aliphatic alcohols studied adsorb on to an α-Al2O3 surface in an open-chain perpendicular fashion.
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Mondal, Suman Kumar, Prasanta Gorai, Milan Sil, Rana Ghosh, Emmanuel E. Etim, Sandip K. Chakrabarti, Takashi Shimonishi i in. "Is There Any Linkage between Interstellar Aldehyde and Alcohol?" Astrophysical Journal 922, nr 2 (30.11.2021): 194. http://dx.doi.org/10.3847/1538-4357/ac1f31.
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Abstract It is speculated that there might be some linkage between interstellar aldehydes and their corresponding alcohols. Here an observational study and astrochemical modeling are coupled together to illustrate the connection between them. The ALMA cycle 4 data of a hot molecular core, G10.47+0.03, are utilized for this study. Various aldehydes (acetaldehyde, propanal, and glycolaldehyde), alcohols (methanol and ethylene glycol), and a ketone (acetone) are identified in this source. The excitation temperatures and column densities of these species were derived via the rotation diagram method assuming local thermodynamic equilibrium conditions. An extensive investigation is carried out to understand the formation of these species. Six pairs of aldehyde–alcohol are considered for this study: (i) methanal and methanol, (ii) ethanal and ethanol, (iii) propanal and 1-propanol, (iv) propenal and allyl alcohol, (v) propynal and propargyl alcohol, and (vi) glycolaldehyde and ethylene glycol. One pair of ketone–alcohol (acetone and isopropanol) and ketene–alcohol (ethenone and vinyl alcohol) are also considered. Two successive hydrogenation reactions in the ice phase are examined to form these alcohols from aldehydes, ketone, and ketene, respectively. Quantum chemical methods are extensively executed to review the ice-phase formation route and the kinetics of these species. Based on the obtained kinetic data, astrochemical modeling is employed to derive the abundances of these aldehydes, alcohols, ketone, and ketene in this source. It is seen that our model could successfully explain the observed abundances of various species in this hot molecular core.