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Microbiological Research Mar 2022The cassava-alcohol fermentation process employing cassava requires nitrogen source to maximize yields by a commercial strain of S. cerevisiae TG1348. In this study, a...
The cassava-alcohol fermentation process employing cassava requires nitrogen source to maximize yields by a commercial strain of S. cerevisiae TG1348. In this study, a factorial experimental design was used to assess a suitable nitrogen source for growth and fermentative performance of S. cerevisiae in cassava-ethanol fermentation. The alcohol fermentation time was about 39 h for urea and ammonium acetate, which was 48 h for ammonium chloride and ammonium sulphate. The fermentation time was reduced by 19 % when using urea and ammonium acetate as nitrogen source. Ammonium acetate leaded to the highest alcohol yield, which was 4% higher than for ammonium sulphate. In addition, byproduct formation differed obviously between the nitrogen sources. The glycerol yields were similar for urea, ammonium sulphate and ammonium chloride but were 24 % lower for ammonium acetate. However, glycerol yield for ammonium carbonate was higher than for other nitrogen sources. Clearly, in batch cultures the ammonium acetate not only increased ethanol generation, but also decreased glycerol generation. In order to understand why ammonium acetate promotes alcohol fermentation, acetic acid was added to different nitrogen sources. The weight loss effect of ammonium sulphate adding acetic acid and ammonium acetate as nitrogen source was the same. The fermentation time was shortened by adding acetic acid. And pH was increased by addition of acetic acid when ammonium sulfate and urea were used as nitrogen sources. The results showed that the acetate root plays an important role in ammonium acetate. The results of this study could facilitate the development of new strategies to control fermentation performance.
Topics: Acetates; Fermentation; Manihot; Saccharomyces cerevisiae
PubMed: 34972024
DOI: 10.1016/j.micres.2021.126868 -
International Journal of Molecular... Jan 2023Short-chain fatty acids as well as their bacterial producers are of increasing interest in inflammatory bowel diseases. Although less studied compared to butyrate,...
High Acetate Concentration Protects Intestinal Barrier and Exerts Anti-Inflammatory Effects in Organoid-Derived Epithelial Monolayer Cultures from Patients with Ulcerative Colitis.
Short-chain fatty acids as well as their bacterial producers are of increasing interest in inflammatory bowel diseases. Although less studied compared to butyrate, acetate might also be of interest as it may be less toxic to epithelial cells, stimulate butyrate-producing bacteria by cross-feeding, and have anti-inflammatory and barrier-protective properties. Moreover, one of the causative factors of the probiotic potency of var. is thought to be its high acetate production. Therefore, the objective was to preclinically assess the effects of high acetate concentrations on inflammation and barrier integrity in organoid-based monolayer cultures from ulcerative colitis patients. Confluent organoid-derived colonic epithelial monolayers ( = 10) were exposed to basolateral inflammatory stimulation or control medium. After 24 h, high acetate or control medium was administered apically for an additional 48 h. Changes in TEER were measured after 48 h. Expression levels of barrier genes and inflammatory markers were determined by qPCR. Pro-inflammatory proteins in the supernatant were quantified using the MSD platform. Increased epithelial resistance was observed with high acetate administration in both inflamed and non-inflamed conditions, together with decreased expression levels of IL8 and TNFα and CLDN1. Upon high acetate administration to inflamed monolayers, upregulation of HIF1α, MUC2, and MKI67, and a decrease of the majority of pro-inflammatory cytokines was observed. In our patient-derived human epithelial cell culture model, a protective effect of high acetate administration on epithelial resistance, barrier gene expression, and inflammatory protein production was observed. These findings open up new possibilities for acetate-mediated management of barrier defects and inflammation in IBD.
Topics: Humans; Colitis, Ulcerative; Intestinal Mucosa; Inflammation; Butyrates; Acetates; Organoids; Colitis
PubMed: 36614212
DOI: 10.3390/ijms24010768 -
Molecular Biology of the Cell Jun 2023The short-chain fatty acid metabolite acetyl-coenzyme A (acetyl-CoA) has emerged as a major signal transducer that can broadly affect cell fate and function, at least...
The short-chain fatty acid metabolite acetyl-coenzyme A (acetyl-CoA) has emerged as a major signal transducer that can broadly affect cell fate and function, at least partly by influencing acetylation of key proteins. The mechanism by which acetyl-CoA regulates CD4 T-cell fate determination remains poorly understood. Herein, we report that acetate modulates glyceraldehyde-3-phosphate dehydrogenase (GAPDH) acetylation and CD4 T helper 1 (Th1) cell differentiation by altering acetyl-CoA levels. Our transcriptome profiling shows that acetate is a robust positive regulator of CD4 T-cell gene expression typical of glycolysis. We further show that acetate potentiates GAPDH activity, aerobic glycolysis, and Th1 polarization through regulation of GAPDH acetylation levels. This acetate-dependent GAPDH acetylation occurs in a dose- and time-dependent manner, while decreasing acetyl-CoA levels by fatty acid oxidation inhibition results in a decline in acetyl-GAPDH levels. Thus, acetate functions as a potent metabolic regulator in CD4 T-cells by promoting GAPDH acetylation and Th1 cell fate decision.
Topics: Acetyl Coenzyme A; Acetylation; Cell Differentiation; Acetates
PubMed: 37133968
DOI: 10.1091/mbc.E23-02-0070 -
TheScientificWorldJournal 2012Various Biginelli compounds (dihydropyrimidinones) have been synthesized efficiently and in high yields under mild, solvent-free, and eco-friendly conditions in a...
Lithium-acetate-mediated Biginelli one-pot multicomponent synthesis under solvent-free conditions and cytotoxic activity against the human lung cancer cell line A549 and breast cancer cell line MCF7.
Various Biginelli compounds (dihydropyrimidinones) have been synthesized efficiently and in high yields under mild, solvent-free, and eco-friendly conditions in a one-pot reaction of 1,3-dicarbonyl compounds, aldehydes, and urea/thiourea/acetyl thiourea using lithium-acetate as a novel catalyst without the addition of any proton source. Comparative catalytic efficiency of lithium-acetate and polyphosphoric acid to catalyze Biginelli condensation is also studied under neat conditions. The reaction is carried out in the absence of any solvent and represents an improvement of the classical Biginelli protocol and an advantage in comparison with FeCl(3)·6H(2)O, NiCl(2)·6H(2)O and CoCl(2)·6H(2)O that were used with HCl as a cocatalyst. Compared to classical Biginelli reaction conditions, the present method has advantages of good yields, short reaction times, and experimental simplicity. The obtained products have been identified by spectral ((1)H NMR and IR) data and their melting points. The prepared compounds are evaluated for anticancer activity against two human cancer cell lines (lung cancer cell line A549 and breast cancer cell line MCF7).
Topics: Acetates; Breast Neoplasms; Catalysis; Cell Line, Tumor; Cell Survival; Female; Humans; Lung Neoplasms; Solvents
PubMed: 22619575
DOI: 10.1100/2012/109432 -
Angewandte Chemie (International Ed. in... May 2022A catalytic enantioselective β-O-elimination reaction is reported in the form of a zirconium-catalyzed asymmetric opening of meso-ketene acetals. Furthermore, a...
A catalytic enantioselective β-O-elimination reaction is reported in the form of a zirconium-catalyzed asymmetric opening of meso-ketene acetals. Furthermore, a regiodivergent β-O-elimination is demonstrated. The reaction proceeds under mild conditions, at low catalyst loadings, and produces chiral monoprotected cis-1,2-diols in good yield and enantiomeric excess. The combination with a Mitsunobu reaction or a one-pot hydroboration/Suzuki reaction sequence then gives access to additional diol and aminoalcohol building blocks. A stereochemical analysis supported by DFT calculations reveals that a high selectivity in the hydrozirconation step is also important for achieving high enantioselectivity, although it does not constitute the asymmetric step. This insight is crucial for the future development of related asymmetric β-elimination reactions.
Topics: Acetals; Catalysis; Oxygen; Stereoisomerism; Zirconium
PubMed: 35263503
DOI: 10.1002/anie.202114044 -
Organic Letters Jul 2023After a recent total synthesis had resolved all issues surrounding the constitution and stereostructure of prorocentin, it was possible to devise a new approach aiming...
After a recent total synthesis had resolved all issues surrounding the constitution and stereostructure of prorocentin, it was possible to devise a new approach aiming at an improved supply of this scarce marine natural product; this compound is a cometabolite of the prototypical phosphatase inhibitor okadaic acid but still awaits detailed biological profiling. The revised entry starts from 2-deoxy-d-glucose; keys to success were a telescoped hemiacetal reduction/acetal cleavage and an exquisitely selective gold/Brønsted acid-cocatalyzed spiroacetalization.
Topics: Okadaic Acid; Enzyme Inhibitors; Furans; Acetals
PubMed: 37358405
DOI: 10.1021/acs.orglett.3c01720 -
International Journal of Molecular... Oct 2022d-Arabinofuranosyl-pyrimidine and -purine nucleoside analogues containing alkylthio-, acetylthio- or 1-thiosugar substituents at the C2' position were prepared from the...
d-Arabinofuranosyl-pyrimidine and -purine nucleoside analogues containing alkylthio-, acetylthio- or 1-thiosugar substituents at the C2' position were prepared from the corresponding 3',5'--silylene acetal-protected nucleoside 2'-exomethylenes by photoinitiated, radical-mediated hydrothiolation reactions. Although the stereochemical outcome of the hydrothiolation depended on the structure of both the thiol and the furanoside aglycone, in general, high d-arabino selectivity was obtained. The cytotoxic effect of the arabinonucleosides was studied on tumorous SCC (mouse squamous cell) and immortalized control HaCaT (human keratinocyte) cell lines by MTT assay. Three pyrimidine nucleosides containing C2'-butylsulfanylmethyl or -acetylthiomethyl groups showed promising cytotoxicity at low micromolar concentrations with good selectivity towards tumor cells. SAR analysis using a methyl β-d-arabinofuranoside reference compound showed that the silyl-protecting group, the nucleobase and the corresponding C2' substituent are crucial for the cell growth inhibitory activity. The effects of the three most active nucleoside analogues on parameters indicative of cytotoxicity, such as cell size, division time and cell generation time, were investigated by near-infrared live cell imaging, which showed that the 2'-acetylthiomethyluridine derivative induced the most significant functional and morphological changes. Some nucleoside analogues also exerted anti-SARS-CoV-2 and/or anti-HCoV-229E activity with low micromolar EC values; however, the antiviral activity was always accompanied by significant cytotoxicity.
Topics: Humans; Mice; Animals; Arabinonucleosides; Nucleosides; Antiviral Agents; Acetals; Thiosugars; COVID-19; Pyrimidine Nucleosides; Sulfhydryl Compounds; Purines; Structure-Activity Relationship
PubMed: 36293420
DOI: 10.3390/ijms232012566 -
Molecules (Basel, Switzerland) Jul 2020The advantageous properties of ethylene glycol diacetate (EGDA) qualify it as a useful substitute for glycerol triacetate (GTA) for various green applications. We...
The advantageous properties of ethylene glycol diacetate (EGDA) qualify it as a useful substitute for glycerol triacetate (GTA) for various green applications. We scrutinised the lipase-mediated acetylation of structurally diverse alcohols in neat EGDA furnishing the range of naturally occurring fragrant acetates. We found that such enzymatic system exhibits high reactivity and selectivity towards activated (homo) allylic and non-activated primary/secondary alcohols. This feature was utilised in the scalable multigram synthesis of fragrant ()-hex-3-en-1-yl acetate in 70% yield. In addition, the Lipozyme 435/EGDA system was also found to be applicable for the chemo-selective acetylation of (hydroxyalkyl) phenols as well as for the kinetic resolution of chiral secondary alcohols. Lastly, its discrimination power was demonstrated in competitive experiments of equimolar mixtures of two isomeric alcohols. This enabled the practical synthesis of 1-pentyl acetate isolated as a single product in 68% yield from the equimolar mixture of 1-pentanol and 3-pentanol.
Topics: Acetates; Acetylation; Alcohols; Catalysis; Green Chemistry Technology; Solvents
PubMed: 32674512
DOI: 10.3390/molecules25143217 -
The Journal of Clinical Investigation Apr 2013When a person consumes ethanol, the body quickly begins to convert it to acetic acid, which circulates in the blood and can serve as a source of energy for the brain and...
When a person consumes ethanol, the body quickly begins to convert it to acetic acid, which circulates in the blood and can serve as a source of energy for the brain and other organs. This study used 13C magnetic resonance spectroscopy to test whether chronic heavy drinking is associated with greater brain uptake and oxidation of acetic acid, providing a potential metabolic reward or adenosinergic effect as a consequence of drinking. Seven heavy drinkers, who regularly consumed at least 8 drinks per week and at least 4 drinks per day at least once per week, and 7 light drinkers, who consumed fewer than 2 drinks per week were recruited. The subjects were administered [2-13C]acetate for 2 hours and scanned throughout that time with magnetic resonance spectroscopy of the brain to observe natural 13C abundance of N-acetylaspartate (NAA) and the appearance of 13C-labeled glutamate, glutamine, and acetate. Heavy drinkers had approximately 2-fold more brain acetate relative to blood and twice as much labeled glutamate and glutamine. The results show that acetate transport and oxidation are faster in heavy drinkers compared with that in light drinkers. Our finding suggests that a new therapeutic approach to supply acetate during alcohol detoxification may be beneficial.
Topics: Acetates; Adult; Alcoholism; Blood Glucose; Brain; Case-Control Studies; Female; Glutamic Acid; Glutamine; Humans; Kinetics; Male; Metabolic Networks and Pathways; Middle Aged; Models, Biological; Oxidation-Reduction; Young Adult
PubMed: 23478412
DOI: 10.1172/JCI65153 -
Applied and Environmental Microbiology Apr 1990The growth characteristics and acetate production of several Escherichia coli strains were compared by using shake flasks, batch fermentations, and... (Comparative Study)
Comparative Study
The growth characteristics and acetate production of several Escherichia coli strains were compared by using shake flasks, batch fermentations, and glucose-feedback-controlled fed-batch fermentations to assess the potential of each strain to grow at high cell densities. Of the E. coli strains tested, including JM105, B, W3110, W3100, HB101, DH1, CSH50, MC1060, JRG1046, and JRG1061, strains JM105 and B were found to have the greatest relative biomass accumulation, strain MC1060 accumulated the highest concentrations of acetic acid, and strain B had the highest growth rates under the conditions tested. In glucose-feedback-controlled fed-batch fermentations, strains B and JM105 produced only 2 g of acetate.liter-1 while accumulating up to 30 g of biomass.liter-1. Under identical conditions, strains HB101 and MC1060 accumulated less than 10 g of biomass.liter-1 and strain MC1060 produced 8 g of acetate.liter-1. The addition of various concentrations of sodium acetate to the growth medium resulted in a logarithmic decrease, with respect to acetate concentration, in the growth rates of E. coli JM105, JM105(pOS4201), and JRG1061. These data indicated that the growth of the E. coli strains was likely to be inhibited by the acetate they produced when grown on media containing glucose. A model for the inhibition of growth of E. coli by acetate was derived from these experiments to explain the inhibition of acetate on E. coli strains at neutral pH.
Topics: Acetates; Acetic Acid; Escherichia coli; Feedback; Fermentation; Glucose; Mutation
PubMed: 2187400
DOI: 10.1128/aem.56.4.1004-1011.1990