Dilute Alcohol Research Articles

Transepithelial Photorefractive Keratectomy-Review.

The type and nature of refractive surgery procedures has greatly increased over the past few decades, allowing for almost all patient populations to be treated to extremely high satisfaction. Conventional photorefractive keratectomy involves the removal of the corneal epithelium through mechanical debridement or dilute alcohol instillation. An improvement to this method utilises laser epithelial removal in a single-step process termed transepithelial photorefractive keratectomy (transPRK). We explore the history of transPRK from its early adoption as a two-step process, identify different transPRK platforms from major manufacturers, and describe the role of transPRK in the refractive surgery armamentarium. This is a narrative review of the literature. This review finds that TransPRK is a safe and effective procedure that works across a variety of patient populations. Though often not seen as a primary treatment option when compared to other corneal-based procedures that offer a faster and more comfortable recovery, there are many scenarios in which these procedures are not possible. These include, but are not limited to, cases of corneal instability, previous refractive surgery, or transplant where higher-order aberrations can impair vision in a manner not amenable to spectacle or contact lens correction. We discuss refinements to the procedure that would help improve outcomes, including optimising patient discomfort after surgery as well as reducing corneal haze and refractive regression.

ETHYL ALCOHOL - WATER SEPARATION BY EXTRACTIVE DISTILLATION: SIMULATION USING ASPEN PLUS™ AND EXPERIMENTAL VALIDATION

Dilute ethyl alcohol (ethanol, EtOH) is produced using fermentation (< 20 mass%), but it needs to be further purified because it contains large water content. EtOH forms an azeotrope with water and to separate this azeotrope, advanced separation processes like pressure swing distillation (PSD), azeotropic distillation (AD), and extractive distillation (ED) are employed. In this work, ethylene glycol (EG) was used as an entrainer in extractive distillation. Vapour liquid equilibrium (VLE) data was used to validate the chosen rigorous thermodynamic model. To find a workable range of operating parameters, sensitivity analysis was performed to find out the number of stages (N), feed stage (NF), distillate rate (DR), and reflux ratio (RR). Simulation shows that use of accurate operating parameters and correct entrainer can help to obtain almost pure EtOH (99.89 mole %, 99.92 mass %). In order to validate the theoretical findings from the simulation, experimental investigations in the form of batch and semi - batch distillation runs were conducted. It was seen from these runs that it is indeed possible to obtain EtOH with high purity. It was also verified that EG can be separated and recycled back with high purity with a very high recovery.

Improving the performance of polyacrylate latex binders for water-based inks through the application of reactive emulsifiers and nanosized zinc oxide

The poor redissolution and low ethanol resistance stability of room temperature self-cross-linking polyacrylate latexes (RTSPLs) made from conventional emulsifiers are the main obstacles for their industrial application in water-based inks. To address these issues, in this study, anionic SR-10 (allyloxy polyoxyethylene ammonium sulfate) /nonionic ER-10 (allyloxy fatty alcohol polyoxyethylene ether) dual-reactive composite emulsifier is developed to replace the conventional 2A1 (sodium dodecyl diphenyl ether disulfonate) /TX-30 (alkyl phenol polyoxyethylene ether) non-reactive composite emulsifier for the synthesis of polyacrylate latexes, and a certain mass of nanosized zinc oxide (ZnO) was added into as-prepared latexes as an ionic cross-linking agent to partially replace the cross-linking monomer of diacetone acrylamide (DAAM). Properties of the latexes and the latex films, with emphasis on redissolution, stability against ethanol, and adhesion on biaxially oriented polypropylene (BOPP) and polyethylene (PE) substrates, were evaluated to study the effect of the reactive emulsifiers and the nanosized ZnO. The application of the reactive composite emulsifier eliminates the disadvantages associated with the desorption from the latex particles and migration during film formation of the non-reactive emulsifier, thus improving the ethanol resistance stability of latexes and adhesion of their inks on BOPP substrate. The introduction of a certain amount of nanosized ZnO to replace DAAM in equimass amounts improves the redissolution but reduces the cross-linking density and water resistance of the latex film. Surprisingly, the addition of nanosized ZnO substantially improves the ethanol stability of latexes. When ZnO replaces DAAM, accounting for approximately 1 wt% of the total monomers, not only the prepared latex exhibits excellent alcohol dilution stability, but also the latex film has a relatively high cross-linking density, good redissolution, and good comprehensive properties. These findings provide an effective, yet simple way to balance the redissolution and high cross-linking degree of latex films while ensuring that the latexes have good ethanol resistance stability.

Development of an Alcohol Dilution-Lyophilization Method for the Preparation of mRNA-LNPs with Improved Storage Stability.

The lipid nanoparticle (LNP) is one of the promising nanotechnologies for the delivery of RNA molecules, such as small interfering RNA (siRNA) and messenger RNA (mRNA). A series of LNPs that contain an mRNA encoding the antigen protein of SARS-CoV-2 were already approved as RNA vaccines against this infectious disease. Since LNP formulations are generally metastable, their physicochemical properties are expected to shift toward a more stable state during the long-time storage of suspensions. The current mRNA vaccines are supplied in the form of frozen formulations with a cryoprotectant for preventing deterioration. They must be stored in a freezer at temperatures from -80 °C to -15 °C. It is thought that therapeutic applications of this mRNA-LNP technology could be accelerated if a new formulation that permits mRNA-LNPs to be stored under milder conditions were available. We previously reported on a one-pot method for producing siRNA-encapsulated LNPs by combining freeze-drying technology with the conventional alcohol dilution method (referred to herein as the "alcohol dilution-lyophilization method"). In this study, this method was applied to the preparation of mRNA-LNPs to provide a freeze-dried formulation of mRNA LNPs. The resulting formulation can be stored at 4 °C for at least 4 months.

Acoustically induced birefringence in polymer aqueous solutions: The case of polyvinyl alcohol

Transient and stationary ultrasonically induced birefringence traces of various relatively dilute poly-vinyl alcohol aqueous solutions were measured over a range 500–1400 kHz of ultrasonic frequencies and 0.02–0.13 W/cm2 of acoustic field amplitudes. The intrinsic value of the stationary birefringence for all polymer solutions investigated in this study was found to be proportional to the solution mass concentration, the square root of the ultrasonic intensity and the frequency of the ultrasound in agreement with theoretical predictions. Systematic analysis of the transient birefringence signals caused by the applied ultrasonic field has been performed in order to evaluate the orientational relaxation times from the viewpoint of dynamics of polymer chain orientation and anisotropy changes in polarizability. The results are discussed in the context of recent experimental studies and theoretical predictions of the ultrasonically induced birefringence in terms of transport phenomena.

A Comprehensive Review on Pharmacological Activities of Alkaloids: Evidence from Preclinical Studies

Plant alkaloids are a broad range of chemical entities that make up one of the biggest classes of natural goods. Even though man has used alkaloids-containing plants for at least 3000 years as medicines, teas, and potions, the chemicals implicated for their action were not determined till the 19th century. Alkaloids' essential nature causes them to form salts when mixed with alkaline solutions or organic acids. Except in extraordinary circumstances, alkaloids salts are generally soluble in water and dilute alcohols, but not in organic solvents. They are classified using a variety of markers, such as natural origins or chemical composition. The distribution of alkaloids according to their primary structure, the major C-N skeleton, is the most correct and frequent categorization. Alkaloids, which are compounds isolated from natural sources, exhibit promising pharmacological activity, including pharmacological activity for the curing of neurogenerative illnesses like vascular dementia, which currently treated with a variety of medications. As a result, the article focuses on the technological prospecting of alkaloids with important properties for curing the illness, such as antioxidant, anxiolytic, anti-inflammatory, antiviral, antiemetic, antifungal, antihyperlipedemic, antihypoglycemic, muscle relaxant, antiulcer, antitussive, expectorant, anticancer, antimicrobial, antimalarial, immunosuppressant, antidepressant.

Study of the effect of sesame oil on the ability of bacteria to infect urinary tracts in adhesion to epithelial cells

Three concentrations of sterile sesame oil were obtained by mineral filters diluted with water (25% ,50% ,75%), as well as three concentrations of the same extract diluted with dilute alcohol at 50% (25% ,50% ,75%). Their inhibitory effect was tested on bacterial isolation that Isolated from samples of healthy women. The results of the statistical analysis showed that the 0.08 concentrations diluted with water and 50% diluted with alcohol were more inhibitory effect of bacterial isolation by measuring the diameter of the inhibition circuit in the petri dishes as well as the microscopic examination and observation of the adhesion of the bacteria to the epithelial cells at a rate of (4 ± 0.1) and (7 ± 0.3 ) Respectively at P ≤00.05.

Electrochemical esterification in distilled liquor via gold catalysis and its application for enhancing ester aroma of low-alcohol liquor

The development of low-alcohol liquor (Baijiu) can represent a tool to solve the problems of excessive alcohol intake. However, low-alcohol liquor has an insufficient ester aroma and a bland taste due to the alcohol dilution process. This study proposes an electrochemical catalysis technology to catalyze the esterification reaction between the acid and alcohol in liquor, thereby enhancing the ester aroma of low-alcohol liquor. In the electrochemical conversion process, the gold electrode with a certain potential promotes the formation of carbocation intermediate from corresponding carboxylic acid, thereby improving the esterification reaction efficiency. The key finding is that the total ester content of liquor treated using this technology is increased by more than 20%, and a strong ester aroma is attained. This study clarifies the electrocatalytic mechanism of the esterification reaction in liquor, and provides a new idea for making low-alcohol liquor become more attractive for aroma and taste aspects trying to obtain an alternative product contributing to the public health.

Toward a Better Understanding of Perceptive Interactions between Volatile and Nonvolatile Compounds: The Case of Proanthocyanidic Tannins and Red Wine Fruity Esters-Methodological, Sensory, and Physicochemical Approaches.

The impact of commercial proanthocyanidic tannins on fruity pool of esters, representing the fruitiness of Bordeaux red wines, was assessed in model solutions. It was shown that the presence of tannins in the matrix significantly attenuated perception of fruity notes (p = 0.013). Physicochemical analysis demonstrated that the presence of proanthocyanidic tannins in dilute alcohol solution resulted in a decrease in ester partition coefficients and thus in a decrease in ester contents in the headspace (p < 0.05). This fact highlighted the changes that may occur in wines at a pre-sensory level, prior to sensory evaluation. Finally, a new sensory tool was developed, consisting in an ISO glass containing two compartments separated by a glass wall, providing a way to compare perceived odors according to whether or not the components of the odor mixtures were actually mixed in solution (p < 0.001). This new tool was used to demonstrate the impact and the only implication of pre-sensory level in the consequences of physical mixture between proanthocyanidic tannins and esters on their odor perception.

In-Vitro Evaluation of Antimicrobial Activities of Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Neisseria gonorrhoeae, and Candida albicans Nosodes.

This study presents the results of the minimum inhibitory concentration (MIC) assay of a series of nosodes: namely Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Neisseria gonorrhoeae, and Candida albicans. Each was tested against its corresponding infection as well as cross infections. In-vitro efficacy of polyvalent nosodes was tested using the MIC assay technique. The nosodes, namely C. albicans polyvalent nosode (35c, 100c), N. gonorrhoeae (35c), K. pneumoniae (35c, 100c), E. coli polyvalent nosode (35c, 100c) and Salmonella typhi polyvalent nosode (30c, 100c), were tested along with positive and negative controls. Nosodes were studied in different potencies and at 1:1 dilution. C. albicans polyvalent nosode 35c, 100c, N. gonorrhoeae 35c, and positive control amphotericin B showed inhibition of the growth of C. albicans species. K. pneumoniae 35c, E. coli polyvalent nosode 100c, and meropenem (positive control) showed inhibition of the growth of K. pneumoniae; this effect was not seen with ceftriaxone, ofloxacin and amoxicillin antibiotics. E. coli polyvalent nosode 30c in 10% alcohol (direct and dilution 1:1) and the positive controls ciprofloxacin, ofloxacin, and amoxicillin showed inhibition of the growth of E. coli. The S. typhi polyvalent nosode 30c in 10% alcohol showed inhibition of growth of S. typhi. This study reveals that the tested nosodes exhibited antibacterial potential against the corresponding micro-organisms and against other selected organisms studied using this assay.

Benchmarking of Separation Methods for Bioethanol (&lt;5 wt %) Recovery

Distillation and dehydration account for around 20 to 40% of the total energy consumption for first-generation bioethanol production. Due to the more dilute alcohol concentrations encountered in the second-generation processes, the conventional separation methods are not economically feasible. The main obstacles are the high-energy input demand and low thermodynamic efficiency. In this work, six alternative advanced layouts for alcohol recovery are simulated and benchmarked based on energy consumptions and thermodynamic efficiencies. Among these is the internally heat integrated distillation column, which, despite the research efforts of the last 40 years, is not yet established in the industry. Feed composition has been varied in the range of 0.75–5.0 wt % ethanol. The analysis results show that intensified distillation schemes can improve second law efficiency of about 65 to 80% and reduce energy consumptions by 67% compared to conventional distillation. The most optimal separation technologies investigated requires about 9.8 to 10.4 MJ/kg-EtOH for 0.75 wt % ethanol feed and 1.9–2.0 MJ/kg-EtOH for 5.0 wt % ethanol feed. These are the externally heat-integrated column, the internally heat-integrated column, and a four-effect distillation sequence. The results obtained in this study can allow for more optimal biofuel production, giving rise to potential improved business for sustainable green technology in the future.

Quantitative Analysis of Pyrazines and Their Perceptual Interactions in Soy Sauce Aroma Type Baijiu.

Pyrazines are important compounds in soy sauce aroma type Baijiu (SSAB). In this work, a total of 16 pyrazines were analyzed using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC–MS/MS) in SSAB. The quantitative results showed that 2,3,5,6-tetramethylpyrazine, 2,6-dimethylpyrazine and 2,3,5-trimethylpyrazine were the three most concentrated pyrazines. The highest odor activity value (OAV) was determined for 2-ethyl-3,5-dimethylpyrazine. Quantitative analysis combined with descriptive sensory analysis revealed that sub-threshold pyrazines (2,3-dimethylpyrazine, 2,3-diethylpyrazine, 2,3-diethyl-5-methylpyrazine and 2-acetyl-3-methylpyrazine) are significantly correlated with the roasted aroma in SSAB. Our study focused on the impact of sub-threshold pyrazines on the perception of roasted aroma in SSAB. The effect of the sub-threshold pyrazines was detected by the addition of various pyrazines in SSAB samples, despite their sub-threshold concentrations. Furthermore, the presence of sub-threshold pyrazines in dilute alcohol solution resulted in a significant reduction in the odor thresholds of supra-threshold pyrazines. Sensory investigation indicated that pyrazines have a synergistic effect on the perception of roasted aroma. The results highlighted the contribution of some pyrazines to the roasted aroma in SSAB despite their sub-threshold concentrations.

Boosting the Antimicrobial Activity of Highly Diluted Aqueous Alcoholic Sanitizers by Fortification with Essential Oil Components: I- Carvacrol

The current study aims at developing alcoholic-based sanitizing formula against some pathogenic bacteria based on highly diluted (< 70.0%) aqueous isopropanol solution which is fortified with small amount of an essential oil component like carvacrol. This phenolic compound can act as antimicrobial booster for the compensation of alcohol reduction in the sanitizer. The solubility behavior of carvacrol in the aqueous alcoholic solution containing different ratios of isopropanol and water was investigated using the Gibbs’ phase diagram. Based on that, a selected formula containing 1.0% carvacrol dissolved in the highest possible dilution of isopropanol (45.0%) was chosen for testing its antimicrobial activity against some gram positive and negative pathogenic bacteria in comparison to the standard 70.0% alcohol formula without carvacrol. Results indicated that a 45.0% aqueous isopropanol solution can hold up to 5.0% carvacrol at maximum in a physically stable and homogenous sanitizing formula. Antimicrobial evaluation of the developed diluted aqueous isopropanol fortified with 1.0% carvacrol showed the same inhibition against the tested pathogenic bacteria as the standard 70.0% alcohol sanitizer without carvacrol. In conclusion, 45.0% diluted isopropanol fortified with a minimum of 1.0% up to 5.0% carvacrol (in case of intensive sanitization) can possibly be used as sanitizer for protection against some pathogenic bacteria. The practical significance of this study is the production of diluted alcoholic sanitizing formula for decontamination of surfaces against some pathogenic bacteria with the advantage of increasing alcohol dilution in order to spare the absolute alcohol reserve for more quantitative production of the sanitizer.

Impact of Whisky Lactone Diastereoisomers on Red Wine Fruity Aromatic Expression in Model Solution.

The impact of whisky lactone diastereoisomers on the typical fruity expression of red Bordeaux wines was evaluated by sensory analysis. The detection thresholds of cis- and trans-whisky lactone in a dilute alcohol solution (12% v/v) were 20 and 130 μg/L, respectively. Consequently, considering their average concentrations found in oak-aged red wines, cis-whisky lactone was present at supra threshold levels, whereas trans-whisky lactone was below its detection threshold. Adding these diastereoisomers to a red wine fruity aromatic reconstitution at these average concentrations led to a decrease in the perception of this last one, highlighting a masking effect. Sensory profiles of cis- and trans-whisky lactone confirmed that these compounds modified the perception of fruity aromas, decreasing the intensity of red berry fruit notes and increasing that of blackberry fruit and spicy descriptors.

Fast deployment of COVID-19 disinfectant from common ethanol of gas stations in Brazil

ObjectivesCoronavirus COVID-19 is spreading very fast in Brazil, requiring innovative strategies for the fast deployment of disinfectants. Panic in population triggered by COVID-19 has caused a shortage of alcohol-based hand sanitizers and disinfectants in many cities of Brazil. Despite the governmental reaction against the outbreak, a risk of shortage of disinfectants still exists. The objective of this research is to investigate an alternative method for the fast deployment of alcohol-based disinfectants to protect the population against COVID-19. Methods and resultsThis research highlights the feasibility of disinfectant production from common ethanol available in Brazilian gas stations, as a last resort. A four-by-one (4:1) ratio of common alcohol diluted in water meets the minimum requirements set by health agencies for the alcoholic concentration of disinfectants. Risks factors on alcohol dilution process are associated with corresponding measures of risk mitigation for public health and safety. Conclusions and perspectivesThis research proposes a process for the production and deployment of ethanol-based disinfectant from gas stations. However, the implementation is not timely possible for the COVID-19 pandemic due to complexities in the productive process. For the post-COVID-19 period, the authors give three perspectives: (a) future investigation of human dermal toxicity of common ethanol, (b) establishment of a program for the ethanol decontamination, and (c) countries such as the US, Sweden, Thailand, and Colombia to rethink their energy policy for the adoption of biofuel E100 (ethanol and water) instead of E85 (blend of ethanol, gasoline, and water), as part of their biodefense strategy.

Correction to “Adsorption of Dilute Alcohols onto Cyclodextrin–Polysulfone Membrane: Experimental and Theoretical Analysis”

Correction to “Adsorption of Dilute Alcohols onto Cyclodextrin–Polysulfone Membrane: Experimental and Theoretical Analysis”

Oak Wood Volatiles Impact on Red Wine Fruity Aroma Perception in Various Matrices.

This research examined the impact of oak wood volatile compounds on the perception of red wine fruity aroma in several matrices. Several aromatic reconstitutions were prepared, consisting of 13 esters, representing the fruity pool of red wine, and 14 oak wood compounds at the various concentrations corresponding to the levels released by light, medium, and heavy toasting of barrels. These reconstitutions were prepared in dilute alcohol solution, dearomatized red wine, and commercial red wine. Sensory analysis revealed the impact of the addition or omission of some oak wood compounds. The "detection threshold" of the fruity pool was then evaluated. The presence of 2-furanmethanethiol individually and the oak wood compound mixture, at concentrations representing various toasting levels, had a significant masking effect on the fruity pool, whereas vanillin had a significant enhancing effect in model solution. Sensory profiles highlighted changes in the perception of fruity nuances in the presence of the oak wood compound mixture. The addition of compounds at concentrations representing different toasting levels led to a predictable increase in the perception of the oak wood descriptors (spicy, smoky, and toasty) in all of the matrices tested. The perception of fruity notes also varied depending upon the toasting level and the complexity of the matrix. In dilute alcohol solution and dearomatized red wine, light toasting preserved or intensified the fruity notes. Generally, in all matrices tested, fresh-fruit and red-berry-fruit notes decreased with the addition of wood at medium and heavy toasting levels.

Enthalpies of dilution of amino alcohols in aqueous solutions at 298.15 K

The enthalpies of dilution of aqueous solutions of the amino alcohols: 3-amino-1-propanol, (RS)-1-amino-2-propanol, (RS)-3-amino-1,2-propanediol, and 1,3-diamino-2-propanol were measured as a function of concentration at 298.15 K using a Thermal Activity Monitor (TAM). The results of the experimental measurements were treated according to the McMillan-Mayer theory, to obtain the enthalpic homogeneous interaction coefficients. The pair interaction coefficient hxx shows a clear dependence on the position and number of polar groups. The enthalpic coefficients are discussed in terms of the molecular interaction between solvated solute molecules.

Hydration characteristics, structural effects and the taste quality of some polyhydroxy compounds in aqueous solutions of nicotinic acid (vitamin B3) at (288.15–318.15) K

Physicochemical properties elucidating the hydration characteristics and structural effects of polyhydroxy compounds in mixed aqueous solutions offer significant information for the growth of pharmaceutical and food industries. Consequently, standard partial molar volumes and isentropic compressibilities at infinite dilution of saccharides, their derivatives and sugar alcohols in (0.01, 0.05, 0.09 and 0.13) mol kg−1 nicotinic acid(aq) (vitamin B3) solutions have been investigated by experimental density and ultrasonic velocity with respect to temperature. Their transfer values, compressibility hydration numbers, apparent massic volumes and isentropic compressibilities have also been determined. These parameters are important to study the taste behavior of polyhydroxy compounds and intermolecular interactions occurring in ternary mixtures. UV absorption spectra of the studied polyhydroxy compounds have been recorded in 1 × 10−4 mol kg−1 nicotinic acid(aq) solutions. The comparison of present results has been made with the studies reported earlier in l-ascorbic acid, thiamine HCl and pyridoxine HCl.

A REVIEW ON PHARMACOLOGICAL ACTIVITIES OF ALKALOIDS

Alkaloids are a category of molecules in nature around the globe with a relatively large occurrence. These are chemicals and biomolecules that are very complex. Alkaloids are compounds of a very diverse class of secondary plant metabolites; alkaloids, such as anticholinergics, antitumor, diuretic, antiviral, antihypertensive, antiulcer, analgesic, and anti-inflammatory, have been linked to the extensive list of biological activities. The basic character of alkaloids allows salts to be formed with mineral acids or organic acids, alkaloid salts are usually soluble in water and dilute alcohols, and are not soluble in organic solvents except in rare cases. This research is carried out mainly in the context and classification of alkaloids and alkaloids pharmacological practices.