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Molecules (Basel, Switzerland) May 2020Due to the nature of the carboxylic group, acetic acid can serve as both a donor and acceptor of a hydrogen bond. Gaseous acetic acid is known to form cyclic dimers with...
Due to the nature of the carboxylic group, acetic acid can serve as both a donor and acceptor of a hydrogen bond. Gaseous acetic acid is known to form cyclic dimers with two strong hydrogen bonds. However, trimeric and various oligomeric structures have also been hypothesized to exist in both the gas and liquid phases of acetic acid. In this work, a combination of gas-phase NMR experiments and advanced computational approaches were employed in order to validate the basic dimerization model of gaseous acetic acid. The gas-phase experiments performed in a glass tube revealed interactions of acetic acid with the glass surface. On the other hand, variable-temperature and variable-pressure NMR parameters obtained for acetic acid in a polymer insert provided thermodynamic parameters that were in excellent agreement with the MP2 (the second order Møller-Plesset perturbation theory) and CCSD(T) (coupled cluster with single, double and perturbative triple excitation) calculations based on the basic dimerization model. A slight disparity between the theoretical dimerization model and the experimental data was revealed only at low temperatures. This observation might indicate the presence of other, entropically disfavored, supramolecular structures at low temperatures.
Topics: Acetic Acid; Algorithms; Gases; Hydrogen Bonding; Magnetic Resonance Spectroscopy; Models, Chemical; Pressure; Quantum Theory
PubMed: 32375390
DOI: 10.3390/molecules25092150 -
Scientific Reports Sep 2019The Asian citrus psyllid (ACP) is a vector of a pathogen associated with greening and thus a major problem in citriculture worldwide. Lures are much needed for improving...
The Asian citrus psyllid (ACP) is a vector of a pathogen associated with greening and thus a major problem in citriculture worldwide. Lures are much needed for improving ACP trapping systems for monitoring populations and surveillance. Previously, we have identified acetic acid as a putative sex pheromone and measured formic acid- and propionic acid-elicited robust electroantennographic responses. We have now thoroughly examined in indoor behavioral assays (4-way olfactometer) and field tests the feasibility of these three semiochemicals as potential lures for trapping ACP. Formic acid, acetic acid, and propionic acid at appropriate doses are male-specific attractants and suitable lures for ACP traps, but they do not act synergistically. An acetic acid-based homemade lure, prepared by impregnating the attractant in a polymer, was active for a day. A newly developed slow-release formulation had equal performance but lasted longer, thus leading to an important improvement in ACP trap capture at low population densities.
Topics: Acetic Acid; Animals; Behavior, Animal; Brazil; California; Citrus; Hemiptera; Male; Pheromones; Volatile Organic Compounds
PubMed: 31501479
DOI: 10.1038/s41598-019-49469-3 -
Journal of Food Science Jan 2022Fresh-cut potato slices are very popular in the service of hot-pots. However, the gelatinized starch easily escaping from the potato cells during cooking causes the...
Fresh-cut potato slices are very popular in the service of hot-pots. However, the gelatinized starch easily escaping from the potato cells during cooking causes the thickening of beef tallow or soup in the hot-pot. Thus, acetic acid is considered for solving the problem of potato slices. Besides, the nutritional and quality characteristics of potato slices are also evaluated in this study. Results show that 1.0%-1.5% (v/v) acetic acid treatment can decrease mass loss and starch digestion rate, and delay the degradation of ascorbic acid and deterioration of color and texture of potato slices. Such treatment also inhibits membrane oxidation and PPO activity, and increase the total phenolic accumulation of potato slice in 7-day storage. The cell wall integrity of the potato slice is strengthened by acetic acid treatment, providing a strategy for the improvement of the boiling resistance of potato slice, and endowing potato slice with the digesting resistance. PRACTICAL APPLICATION: Acid pretreatment would cause the intensification of potato cell wall, which finally decrease the in vitro digestibility through decrease of leakage of gelatinized starch from potato cell and the contact between gelatinized starch and digesting enzyme. This observation proved that the integrity of cell structure in vegetable is important for their processing quality improvement (especially for their hardness improvement after heating or fermentation).
Topics: Acetic Acid; Cooking; Hardness; Solanum tuberosum; Starch
PubMed: 34953084
DOI: 10.1111/1750-3841.16000 -
FEMS Yeast Research Jan 2024Maintenance of asymmetric ion concentrations across cellular membranes is crucial for proper yeast cellular function. Disruptions of these ionic gradients can... (Review)
Review
Maintenance of asymmetric ion concentrations across cellular membranes is crucial for proper yeast cellular function. Disruptions of these ionic gradients can significantly impact membrane electrochemical potential and the balance of other ions, particularly under stressful conditions such as exposure to acetic acid. This weak acid, ubiquitous to both yeast metabolism and industrial processes, is a major inhibitor of yeast cell growth in industrial settings and a key determinant of host colonization by pathogenic yeast. Acetic acid toxicity depends on medium composition, especially on the pH (H+ concentration), but also on other ions' concentrations. Regulation of ion fluxes is essential for effective yeast response and adaptation to acetic acid stress. However, the intricate interplay among ion balancing systems and stress response mechanisms still presents significant knowledge gaps. This review offers a comprehensive overview of the mechanisms governing ion homeostasis, including H+, K+, Zn2+, Fe2+/3+, and acetate, in the context of acetic acid toxicity, adaptation, and tolerance. While focus is given on Saccharomyces cerevisiae due to its extensive physiological characterization, insights are also provided for biotechnologically and clinically relevant yeast species whenever available.
Topics: Acetic Acid; Homeostasis; Saccharomyces cerevisiae; Adaptation, Physiological; Stress, Physiological; Ions; Hydrogen-Ion Concentration
PubMed: 38658183
DOI: 10.1093/femsyr/foae016 -
Sensors (Basel, Switzerland) Mar 2022An optical pH sensor that enables the non-destructive measurement of acetic acid and its distribution in a photovoltaic module during damp heat (DH) testing is reported....
An optical pH sensor that enables the non-destructive measurement of acetic acid and its distribution in a photovoltaic module during damp heat (DH) testing is reported. The sensor was fabricated by impregnating a solution of a pH-sensitive fluorescent dye into a fluororesin membrane filter, which was then dried. While conducting the DH test, fluorescence spectra from 20 pH sensors were periodically recorded and converted into pH values using a predetermined calibration curve. As a result, we succeeded in measuring changes in pH with a DH test time of up to 2000 h, and it was possible to obtain information on the pH distribution in the module. We also confirmed no change in pH in a module with a silicone encapsulant free from acetic acid, and revealed that the sensor that we developed does not respond to moisture and heat, but only to acetic acid.
Topics: Acetic Acid; Calibration; Fluorescent Dyes; Hot Temperature; Hydrogen-Ion Concentration
PubMed: 35408134
DOI: 10.3390/s22072520 -
Food Additives & Contaminants. Part A,... Jun 2020The effects of acid soaking as a pre-treatment on the glycoalkaloid and acrylamide levels in raw and cooked potatoes (French fries) were examined. Soaking raw potato...
The effects of acid soaking as a pre-treatment on the glycoalkaloid and acrylamide levels in raw and cooked potatoes (French fries) were examined. Soaking raw potato cuts in 1.0%, 2.5% or 5.0% acetic acid solutions for at least 8 hours resulted in >90% reduction of α-solanine and α-chaconine in potato samples. Processing of pre-acid soaked potato cuts into French fries resulted in an additional >50% decrease in the glycoalkaloid contents in the samples. Soaking time was found to be a more important factor in reducing glycoalkaloid levels compared to the acid solution concentrations. Over a 95% reduction in acrylamide was also observed in potato cuts pre-soaked in acetic acid before cooking. The reduction in acrylamide formation in the pre-soaked French fry samples was attributed to the lowered pH and the removal of reducing sugars and asparagine in the raw samples prior to cooking. Findings in this study demonstrate that pre-treatment using acid soaking provides a simple and effective way to mitigate glycoalkaloid and acrylamide levels in potatoes.
Topics: Acetic Acid; Acrylamide; Alkaloids; Food Analysis; Food Contamination; Food Handling; Solanum tuberosum
PubMed: 32240039
DOI: 10.1080/19440049.2020.1743883 -
Microbiology (Reading, England) Jul 2023, a combination of honey and vinegar, has been used as a remedy for wounds and infections in historical and traditional medical settings. While honey is now clinically...
, a combination of honey and vinegar, has been used as a remedy for wounds and infections in historical and traditional medical settings. While honey is now clinically used to treat infected wounds, this use of a complex, raw natural product (NP) mixture is unusual in modern western medicine. Research into the antimicrobial activity of NPs more usually focuses on finding a single active compound. The acetic acid in vinegar is known to have antibacterial activity at low concentrations and is in clinical use to treat burn wound infections. Here, we investigated the potential for synergistic activity of different compounds present in a complex ingredient used in historical medicine (vinegar) and in an ingredient mixture (). We conducted a systematic review to investigate published evidence for antimicrobial effects of vinegars against human pathogenic bacteria and fungi. No published studies have explicitly compared the activity of vinegar with that of a comparable concentration of acetic acid. We then characterized selected vinegars by HPLC and assessed the antibacterial and antibiofilm activity of the vinegars and acetic acid, alone and in combination with medical-grade honeys, against and . We found that some vinegars have antibacterial activity that exceeds that predicted by their acetic acid content alone, but that this depends on the bacterial species being investigated and the growth conditions (media type, planktonic vs. biofilm). Pomegranate vinegars may be particularly interesting candidates for further study. We also conclude that there is potential for acetic acid, and some vinegars, to show synergistic antibiofilm activity with manuka honey.
Topics: Humans; Acetic Acid; Honey; Anti-Bacterial Agents; Biofilms; Biological Products
PubMed: 37435775
DOI: 10.1099/mic.0.001351 -
International Journal of Food... Aug 2022Organic acids and their salts are usually the first choice in the bread industry to restrict fungal spoilage, but their efficacy is pH-dependent and spoilage by fungi...
Organic acids and their salts are usually the first choice in the bread industry to restrict fungal spoilage, but their efficacy is pH-dependent and spoilage by fungi remains as a common threat. Therefore, this study aimed to evaluate the susceptibility of spoilage fungi of bakery products to acetic, sorbic, and propionic acids at different pH. Penicillium roqueforti, Penicilium paneum, Aspergillus pseudoglaucus, Aspergillus montevidensis and Hyphopichia burtonii strains isolated from spoiled products had their minimum inhibitory concentration (MIC) defined by macrodilution. The concentrations tested were: (i) sorbic acid up to 32 mM; (ii) propionic acid up to 1024 mM and (iii) acetic acid up to 800 mM with pH adjusted in 4.5, 5.0, 5.0 and 6.0 after setting the agent concentration. The lowest MICs for all agents were obtained at pH 4.5, usually doubling with every 0.5 pH increase. P. roqueforti strains isolated from spoiled products were the most resistant to all tested preservatives; while strains of the related species P. paneum, showed similar tolerance to acetic and propionic acids but was double more susceptible to sorbic acid. Strains of A. pseudoglaucus and A. montevidensis were indistinctly susceptible to the preservatives and were the most susceptible species to propionic and acetic acids. H. burtonii strains demonstrated the most variable behaviour in comparison to the other strains being the most susceptible to sorbic acid, were like Aspergillus strains regarding propionic acid, but tolerate well acetic acid. Propionic acid concentrations usually allowed in baked goods are lower than the concentrations required to inhibit the most tolerant isolates tested in this study. The same is true for sorbic acid at higher pH levels. Spoilage species of bakery ware presents a distinct susceptibility profile to the preservatives commonly used in this sector, but the high tolerance observed is a cause of concern.
Topics: Acetic Acid; Acids; Bread; Food Preservatives; Fungi; Hydrogen-Ion Concentration; Propionates; Sorbic Acid
PubMed: 35643035
DOI: 10.1016/j.ijfoodmicro.2022.109723 -
Journal of Hazardous Materials Feb 2023Neonicotinoids pose potential serious risks to human health even at environmental concentration and their removal from water is considered as a great challenge. A novel...
Ball milling and acetic acid co-modified sludge biochar enhanced by electrochemistry to activate peroxymonosulfate for sustainable degradation of environmental concentration neonicotinoids.
Neonicotinoids pose potential serious risks to human health even at environmental concentration and their removal from water is considered as a great challenge. A novel ball milling and acetic acid co-modified sludge biochar (BASBC) was the first time synthesized, which performed superior physicochemical characteristics including larger surface area, more defect structures and functional groups (e.g., CO and -OH). Electrochemistry was introduced to enhance BASBC for peroxymonosulfate (PMS) activation (E/BASBC/PMS) to degrade environmental concentration neonicotinoids (e.g., imidacloprid (IMI)). The degradation efficiency of IMI was 95.2% within 60 min (C (PMS)= 1 mM, E= 25 V, m (BASBC)= 10 mg). Solution pH and anionic species/concentrations were critical affecting factors. The scavenging and electron paramagnetic resonance experiments suggested that OH and O were the dominant reactive oxygen species contributing to IMI degradation. Three degradation pathways were proposed and pathway Ⅲ was the main one. 86.1% of IMI were mineralized into non-toxic CO and HO, and others were converted into less toxic intermediates. Also, E/BASBC/PMS system achieved the sustainable degradation of IMI in the cycle experiments. Additionally, it exhibited excellent degradation performance for other three typical neonicotinoids (96.6% of thiacloprid (THI), 96.5% of thiamethoxam (THX) and 82.6% of clothianidin (CLO)) with high mineralization efficiencies (87.8% of THI, 90.5% of THX and 75.4% of CLO).
Topics: Humans; Acetic Acid; Sewage; Electrochemistry; Neonicotinoids; Thiamethoxam
PubMed: 36403449
DOI: 10.1016/j.jhazmat.2022.130336 -
Carbohydrate Polymers Mar 2022Acetylated acid-ethanol hydrolyzed (AHS) and acetylated debranched starch (ADS) were investigated as prospective nanocarriers. Both acid-ethanol hydrolysis and...
Acetylated acid-ethanol hydrolyzed (AHS) and acetylated debranched starch (ADS) were investigated as prospective nanocarriers. Both acid-ethanol hydrolysis and debranching decreased the molecular weight and viscosity of starch. Acid-ethanol hydrolyzed starch remained the original microstructure, which was confirmed by results of scanning electron microscopy. New absorption peaks in FTIR spectra of starch confirmed the occurrence of acetylation. The substitution degree (DS) of ADS could reach up to 1.18, while that of AHS could be improved by increasing the ethanol concentration. The developed nanoparticles showed uniform spherical structure and the size of that approximated 180-260 nm. The critical micelle concentration was 0.049 mg/mL, and the shift in fluorescence spectra confirmed the interaction between starch and curcumin. These results indicate show that high DS of AHS and ADS could be used as a potential carrier for curcumin delivery.
Topics: Acetic Acid; Acetylation; Curcumin; Drug Carriers; Ethanol; Hydrolysis; Micelles; Nanoparticles; Starch
PubMed: 34980359
DOI: 10.1016/j.carbpol.2021.119019