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1.
Food Chem ; 366: 130526, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34274705

RESUMO

An in-house method, employing magnetic stirring-assisted aqueous extraction combined with gas chromatography-flame ionization detector, for determination of ethanol in different foods and beverages was validated according to the ISO/IEC 17025 standard. Validation parameters, including selectivity, method limits of detection (approx. 0.006 mg/g) and quantification (approx. 0.02 mg/g), linearity (R2 of >0.999), trueness (relative biases of <3%), accuracy (recoveries of 96-105%), and precision (relative standard deviations of <5%), were satisfactory. The proposed method was as accurate and precise as and more sensitive than the AOAC method 2016.12, with estimated relative expanded uncertainties of around 8% for all samples. The validated method was successfully applied for determination of ethanol in 108 commercially processed foods and beverages, and it could be used for halal verification. Accordingly, this study provided a reliable method for routine quantitative analysis of ethanol in processed foods and beverages to ensure their halal integrity prior to halal certification.


Assuntos
Bebidas , Etanol , Bebidas/análise , Cromatografia Gasosa , Fenômenos Magnéticos , Água
2.
Chemosphere ; 286(Pt 1): 131587, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34303047

RESUMO

Alcohols could be the biggest factor for the improvement of world biofuel economy in the present century due to their excellent properties compared to petroleum products. The primary concerns of sustainable alcohol production for meeting the growing energy demand owing to the selection of viable feedstock and this might enhance the opportunities for developing numerous advanced techniques. In this review, the valorization of alcohol production from several production routes has been exposed by covering the traditional routes to the present state of the art technologies. Even though the fossil fuel conversion could be dominant method for methanol production, many recent innovations like photo electrochemical synthesis and electrolysis methods might play vital role in production of renewable methanol in future. There have been several production routes for production of ethanol and among which the fermentation of lignocellulose biomass would be the ultimate choice for large scale shoot up. The greenhouse gas recovery in the form of alcohols through electrochemistry technique and hydrogenation method are the important methods for commercialization of alcohols in future. It is also observed that algae based renewable bio-alcohols is highly influenced by carbohydrate content and sustainable approaches in algae conversion to bio-alcohols would bring greater demand in future market. There is a lack of innovation in higher alcohols production in single process and this could be bounded by combining dehydrogenation and decarboxylation techniques. Finally, this review enlists the opportunities and challenges of existing alcohols production and recommended the possible routes for making significant enhancement in production.


Assuntos
Biocombustíveis , Éteres , Biomassa , Etanol , Fermentação
3.
Chemosphere ; 286(Pt 1): 131361, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34280833

RESUMO

The continuous dredging of sediments contaminated by polycyclic aromatic hydrocarbons such as phenanthrene (PHE) has required the employment of high-efficiency technologies, including sediment washing (SW). However, the large amount of generated spent SW effluents requires the development of effective, eco-friendly and cost-saving approaches, which can tackle the waste formation in favor of the recovery of chemicals. This study proposes the treatment of a spent SW solution containing ethanol (EtOH) as extracting agent, by testing different initial PHE concentrations (i.e. 20-140 mg L-1) within six consecutive cycles in a fed-batch bioreactor under aerobic conditions. The biological process achieved a PHE removal of 63-91% after the enrichment of PHE-degrading bacteria and the proper supplementation of nutrients, and was mainly affected by the initial PHE concentration value and the excessive decrease of pH and dissolved oxygen. Achromobacter, Sphingobacterium and Dysgonomonas genera were mainly involved in PHE degradation, which followed a first-order kinetic model (R2 = 0.652-0.928) with a degradation rate and half-life time of 0.127-1.177 d-1 and 0.589-2.912 d, respectively. A techno-economic assessment revealed that a virtuous operation of SW, EtOH recovery and biodegradation of the SW solution can allow the recovery of up to 1.35 tons of EtOH per ton of remediated sediment and the decrease of the overall costs by 50%.


Assuntos
Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos , Biodegradação Ambiental , Etanol , Sedimentos Geológicos , Hidrocarbonetos Policíclicos Aromáticos/análise
4.
Addict Behav ; 124: 107110, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34530209

RESUMO

BACKGROUND: Alcohol use varies throughout the year and often peaks on weekends or during celebrations (e.g., New Year's). There is not a perfect correlation between alcohol use and negative consequences, and the extent to which one particularly risky consequence-an alcohol-related blackout-is more common during certain times of the year is unknown. Identifying when blackouts occur may help identify which periods are associated with more risk and be critical in designing public health campaigns. Thus, we examined Twitter data to ascertain whether alcohol-related blackouts occur more during certain holidays/celebrations than typical weekends and whether they differed in timing from general alcohol-related Tweets. METHODS: We used a Twitter-sponsored platform to access unique Tweets written in the United States referencing blackouts (e.g., "blackout") and alcohol generally (e.g., "drunk"). RESULTS: The final dataset included 3.5 million blackout Tweets and 591 million alcohol Tweets (written between 2009 and 2020). Both blackout and alcohol Tweets were written in the late evening, on weekends, and during certain holidays (New Years, St. Patrick's). However, relative to typical weekends, only blackout Tweets were more common during Thanksgiving and only general alcohol-related Tweets were more common during Cinco de Mayo. CONCLUSION: While blackout and alcohol-related Tweets were similar in time of day (peaking in the evening) and day of week (peaking on weekends), they differed during certain celebrations/holidays, suggesting that while alcohol use may be more common during some celebrations, others are more associated with serious harms.


Assuntos
Intoxicação Alcoólica , Alcoolismo , Amnésia Anterógrada , Mídias Sociais , Consumo de Bebidas Alcoólicas/epidemiologia , Etanol , Humanos , Estados Unidos/epidemiologia
5.
Addict Behav ; 124: 107120, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560423

RESUMO

BACKGROUND: Pre-gaming, or drinking before going out, is common among young adults and associated with heavier drinking and negative consequences. However, findings have been mixed as to whether a unique, day-level association between pre-gaming and negative consequences exists independent of alcohol intake. It is also unknown whether young adults experience more positive consequences of alcohol use on days they engage in pre-gaming. This study tested day-level associations between pre-gaming and positive and negative consequences, controlling for same-day alcohol intake, as well as whether these associations were moderated by person- and day-level variables. METHODS: Participants were 148 young adult heavy drinkers (Mage = 20.30, SDage = 1.45, 57.4% female) who reported past-month simultaneous alcohol and marijuana use. For up to 14 consecutive days, participants completed electronic surveys asking about their drinking behaviors and consequences the previous day. RESULTS: Prior to adjusting for alcohol intake, Poisson multilevel models showed that participants reported more negative and positive consequences on days they pre-gamed and those who reported pre-gaming more often throughout the study also experienced more negative and positive consequences overall. After controlling for alcohol intake, a positive, day-level association between pre-gaming and positive consequences remained. There was no evidence of moderation of study associations by person- or day-level variables. CONCLUSION: The unique association between pre-gaming and positive consequences may help explain why pre-gaming is linked with heavy drinking and other risky behaviors as positive consequences have been shown to reinforce such behaviors. Findings suggest pre-gaming may be a useful intervention point for alcohol reduction programs.


Assuntos
Intoxicação Alcoólica , Fumar Maconha , Uso da Maconha , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Etanol , Feminino , Humanos , Lactente , Masculino , Uso da Maconha/epidemiologia , Adulto Jovem
6.
Addict Behav ; 124: 107118, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34583272

RESUMO

Simultaneous alcohol and marijuana use (SAM) such that their effects overlap has emerged as a behavior that is riskier than using either substance separately. It has been associated with high-risk binge drinking and driving while intoxicated during young adulthood, and it has been demonstrated to cause greater physical and mental impairment than use of alcohol or marijuana separately. To identify intervention and prevention targets specific to SAM, we examined the relationships between alcohol- and marijuana-specific beliefs and attitudes (risk factors) and self-reported SAM compared to non-simultaneous co-use (CAM) and alcohol use only in the past 30 days in a sample of young adults (n = 1,023, mean age = 23.17; SD = 0.43). Of those who reported drinking alcohol in the past 30 days, 20.7% reported SAM, 12.6% reported CAM, and 66.6% reported using only alcohol. Results from multinomial logistic regression analyses indicated that some marijuana-specific risk factors (e.g., belief that it is not at all wrong for someone their age to use marijuana) differentiated SAM or CAM from alcohol use only, but alcohol-specific risk factors generally did not. However, the perceptions that parents approved of their using marijuana or frequently drinking heavily were associated with a greater likelihood of SAM compared to CAM (OR ranged from 2.25 to 3.53). Findings point to the salience of individuals' attitudes and beliefs around marijuana use and their perception of parental approval of heavy drinking and marijuana use as potential targets for prevention programs targeting risk reduction among young adults.


Assuntos
Cannabis , Fumar Maconha , Uso da Maconha , Adulto , Consumo de Bebidas Alcoólicas , Etanol , Humanos , Uso da Maconha/epidemiologia , Adulto Jovem
7.
J Sci Food Agric ; 102(1): 175-184, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34061382

RESUMO

BACKGROUND: To improve the aroma of kiwi wine through the utilization of Wickerhamomyces anomalus, kiwi juice was fermented using a selected W. anomalus strain in pure culture and mixed fermentations with Saccharomyces cerevisiae, which was inoculated simultaneously and sequentially. The physicochemical indices, volatile compounds and aroma properties of the kiwi wines were assessed. RESULTS: The study suggested that the ethanol, color indices and organic acids of the wines were closely related to the method of inoculation. Compared with the pure S. cerevisiae fermentation, the mixed fermentations produced more varieties and concentrations of volatiles. The sequential fermentations increased the concentrations of esters and terpenes, improving the flower and sweet fruit notes of the wines. The simultaneous inoculation enhanced the contents of esters and aldehydes, intensifying the flower, sweet and sour fruit of the wines. Partial least-squares regression analysis showed that esters and terpenes contributed greatly to the flower and sweet fruit aroma, whereas aldehydes were the major contributors to the sour note. CONCLUSION: Based on our results, the mixed fermentations not only enriched the types and concentrations of volatiles, but also had better sensory properties. © 2021 Society of Chemical Industry.


Assuntos
Actinidia/microbiologia , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/metabolismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Vinho/análise , Actinidia/metabolismo , Etanol/análise , Etanol/metabolismo , Fermentação , Frutas/metabolismo , Frutas/microbiologia , Humanos , Odorantes/análise , Paladar , Vinho/microbiologia
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120245, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34364037

RESUMO

Simultaneous saccharification and fermentation (SSF) of cassava is one of the key steps in the production of fuel ethanol. In order to improve the monitoring efficiency of the ethanol production process and the product yield, this study puts forward a new idea for monitoring of the cassava SSF process based on the molecular spectroscopy fusion (MSF) technique. Savisky-Golay (SG) combined with standard normal variable (SNV) was used to preprocess the obtained Raman spectra and near-infrared (NIR) spectra. Competitive adaptive reweighted sampling (CARS) was used to optimize the characteristic wavelengths of the preprocessed Raman spectra and the NIR spectra, and the optimized features were fused in the feature layer. The support vector machine (SVM) model of the process parameters during the cassava SSF based on the MSF features was established. The experimental results showed that compared with the best CARS-SVM model based on the single-molecule spectral features, the performance of the best CARS-SVM model based on fusion features has been significantly improved. For detection of the glucose content, the RMSEP, RP2 and RPD of the best CARS-SVM model were 5.398, 0.957 and 4.922, respectively. For detection of the ethanol content, the RMSEP, RP2 and RPD of the best CARS-SVM model were 4.394, 0.977 and 6.758, respectively. The obtained results reveal that the combination of MSF technique and appropriate chemometric methods can achieve high-precision quantitative detection of the process parameters during the cassava SSF. This study can provide technical basis and experimental reference for the development of portable spectrometer equipment for process monitoring of the cassava SSF.


Assuntos
Manihot , Etanol , Fermentação , Máquina de Vetores de Suporte
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120266, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34391063

RESUMO

In this paper, two tetrahydo[5]helicene-based dyes (THH1 and THH2) were studied on their twist intramolecular charge transfer. And the water-soluble blue carbon dots (N-CDs) were synthesized. Considering that their different optical propeties, the ratiometric fluorescence probes N-CDs/THH1 and N-CDs/THH2 were constructed by mixing N-CDs and dyes simply. It was found that N-CDs/THH1 and N-CDs/THH2 could quickly and sensitively detect water content in ethanol, with linear range of 0.500-25.0 vol% and 0.500-30.0 vol%, respectively. What's more, through the actual sample test, it showed that the detection had good accuracy and precision. At the same time, it was found that two ratiometric probes could also be applied to the thermometry with good reversibility based on optical temperature sensors.


Assuntos
Corantes Fluorescentes , Pontos Quânticos , Etanol , Temperatura , Água
11.
Food Chem ; 369: 130769, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34461509

RESUMO

A colorimetric indicator cube for use in smart packaging was designed and fabricated to detect ethanol produced by microbial fermentation in preserved baby mangoes. The presence and level of ethanol was indicated by color variations of the indicator cube, which consists of porous melamine foam (MF) that entraps an indicator solution of potassium dichromate and sulfuric acid. Within the packaging, the cube sits behind a gas-permeable membrane. The morphological structure of MF was studied by digital microscope and X-ray fluorescence analysis. In the optimal condition, the indicator cube exhibited distinct color changes from yellow to brown, green and blue over an ethanol concentration range from 0.25% to 5.0%. Color changes were clearly visible to the naked eye. The repeatability of the ethanol indicator cube was good and storage stability was maintained for up to 19 and 74 days at room and refrigeration temperatures, respectively. The smart packaging was applied to detect ethanol in preserved baby mangoes at different storage times.


Assuntos
Colorimetria , Mangifera , Etanol , Embalagem de Produtos , Refrigeração
12.
J Pharm Biomed Anal ; 207: 114426, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34689062

RESUMO

Alcoholism is a severe threat to public health, and there are no adequate treatments for alcoholic liver disease. The aim of this study was to identify bioactive peptides derived from natural proteins that prevent acute alcohol-induced liver injury. We identified a peptide with the sequence Gly-Leu-hydroxyproline-Gly-Glu-Arg (GLpGER) from the hydrolysate of crucian carp swim bladder using size-exclusion chromatography and reversed-phase chromatography. The in vitro EC50 value of GLpGER to activate alcohol dehydrogenase (ADH) was 137.9 ± 9 µM. Molecular docking experiments indicated that the mechanism by which GLpGER activates ADH may be related to the formation of stable complexes with ADH active pockets through hydrogen bonding, and electrostatic and hydrophobic interactions. Oral administration of GLpGER one hour before acute alcohol ingestion significantly increased alcohol metabolism, manifesting as reduced incidence of the loss of righting reflex, increased alcohol tolerance time, shortened sobering time, and decreased blood alcohol concentration level. GLpGER restored liver ADH activity, maintained the typical morphology of hepatocytes, and reduced serum levels of alanine aminotransferase and aspartate aminotransferase. These findings suggest that GLpGER might reduce acute alcohol-induced liver injury and may have the potential to be developed as an anti-inebriation ingredient.


Assuntos
Carpas , Doença Hepática Crônica Induzida por Substâncias e Drogas , Álcool Desidrogenase , Animais , Concentração Alcoólica no Sangue , Etanol , Fígado , Camundongos , Simulação de Acoplamento Molecular , Peptídeos , Bexiga Urinária
13.
Int J Food Microbiol ; 361: 109463, 2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-34742143

RESUMO

This study aimed to identify the phenolic compounds contained in propolis and to evaluate the effect of propolis and its extracts on the antifungal activity, pH, color, and sensory analysis of creamy cheese with thyme (thyme labneh). Ethanolic and water extracts of propolis were evaluated to determine its phenolic compound content and antioxidant activity. Phenolic compounds in propolis were identified and quantified using gas chromatography-mass spectrometry (GC-MS). Antifungal activities, color, pH, and sensory evaluation of propolis and its extracts (water and ethanolic) were investigated at concentrations of 0.5%, 1%, and 1.5%. The results showed 11 phenolic compounds in the propolis extract. Our findings revealed a significant difference in phenolic content and antioxidant activity in the ethanolic extract of propolis when compared with the water extract (P < 0.05). Microbial counts in thyme labneh treated with propolis powder and its extracts (ethanolic and water) showed significant differences compared with the control at all concentrations (0.5%, 1%, and 1.5%). Propolis powder and ethanolic extracts at concentrations of 1% and 1.5% were limited the rapid growth of mold and yeast, so the results showed no significant difference between 14 and 21 days for these samples. In addition, the 1.5% water extract did not show a significant difference (P > 0.05) between Days 14 and 21. The sensory panel did not detect a significant difference in any sensory attribute in the thyme labneh treated with propolis extracts. This study identified the significant antioxidant and antimicrobial effectiveness of using propolis in dairy products, suggesting its potential as a natural preservative.


Assuntos
Anti-Infecciosos , Própole , Antioxidantes/farmacologia , Etanol , Fenóis , Extratos Vegetais/farmacologia , Própole/farmacologia
14.
Bioresour Technol ; 343: 126071, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34606923

RESUMO

One of the potential bioresources for bioethanol production is Napier grass, considering its high cellulose and hemicellulose content. However, the cost of pretreatment hinders the bioethanol produced from being economical. This study examines the effect of hydrothermal process with dilute acid on extruded Napier grass, followed by enzymatic saccharification prior to simultaneous saccharification and co-fermentation (SScF). Extrusion facilitated lignin removal by 30.2 % prior to dilute acid steam explosion. Optimum pretreatment condition was obtained by using 3% sulfuric acid, and 30-min retention time of steam explosion at 190 °C. Ethanol yield of 0.26 g ethanol/g biomass (60.5% fermentation efficiency) was attained by short-term liquefaction and fermentation using a cellulose-hydrolyzing and xylose-assimilating Saccharomyces cerevisiae NBRC1440/B-EC3-X ΔPHO13, despite the presence of inhibitors. This proposed method not only reduced over-degradation of cellulose and hemicellulose, but also eliminated detoxification process and reduced cellulase loading.


Assuntos
Saccharomyces cerevisiae , Xilose , Celulose/metabolismo , Etanol , Fermentação , Hidrólise , Lignina/metabolismo , Saccharomyces cerevisiae/metabolismo , Ácidos Sulfúricos
15.
Bioresour Technol ; 343: 126153, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34673190

RESUMO

Bioethanol is a major biofuel in industry and mainly produced from corn starch with the dry-mill process. However, one of the remaining challenges is how to economically and efficiently exploit the wasted co-products to further improve ethanol production and generate more valuable chemicals. Here, an integrative approach was developed to efficiently utilize the waste cake for ethanol production, accompanied by protein extraction for feed additives. A high-quality protein feed was produced by the ethanol-alkali extraction method (extraction rate up to 46.91%). Notably, by applying two-step chemoenzymatic strategy, the supernatant and solid recycling yield up to 4.1-, 3.8-, and 154-fold improvements of ethanol, glucose, and xylose production, respectively, comparing to non-pretreatment. Moreover, mass balance analysis found this approach significantly contributed 1.74-4.42% (5.96-15.11 kg/ton dry corn) increase of total ethanol production. The gained knowledge about process design holds the potential transferability for other sustainable biowaste management and bioethanol industry.


Assuntos
Biocombustíveis , Etanol , Fermentação , Resíduos/análise , Xilose
16.
Braz. j. oral sci ; 20: e211194, jan.-dez. 2021. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1253930

RESUMO

Aim: The aim of this study was to evaluate the effect of ethanol-conditioned dentin on endodontic sealer penetration into dentinal tubules by confocal laser scanning microscopy (CLSM). Methods: Forty human maxillary anterior teeth were instrumented and divided into four groups (n = 10) according to the drying methods: 1) wet: vacuum only, 2) paper points: vacuum + absorbent paper points, (3) 70% ethanol: 70% ethanol (1 min) + vacuum + absorbent paper points, and (4) 100% ethanol: 100% ethanol (1 min) + vacuum + absorbent paper points. All root canals were filled with resin-based endodontic sealer. Four sections from each third (cervical, middle, and apical) were examined by CLSM. Root canal wall perimeter infiltrated by sealer, maximum depth of sealer penetration, percentage of penetrated area, and fluorescence intensity of rhodamine B were measured. Statistical analysis was performed by analysis of variance and Tukey's tests (α = 0.05). Results: No statistical difference was found when percentage of root canal wall coverage infiltrated by sealer were compared. The groups in which ethanol solutions were used presented greater depth of sealer penetration, higher percentage of penetrated area, and higher fluorescence intensity of rhodamine B (p< 0.05) when compared with the wet and paper point groups. Overall, 100% ethanol produced better results than 70% ethanol, except for rhodamine B intensity (cervical third). In addition, the absorbent paper points drying method behaved better than did vacuum only group, except for rhodamine B intensity (apical third). Conclusion: Ethanol-conditioned dentin improved the penetration of resin-based sealer into dentinal tubules, especially at the concentration of 100%


Assuntos
Humanos , Molhabilidade , Microscopia Confocal , Cimentos de Resina , Dentina , Etanol , Endodontia
17.
Anal Chim Acta ; 1186: 339126, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34756257

RESUMO

CuxO nanorods with excellent NADH peroxidase mimics were synthesized by a simple hydrothermal method. The catalytic oxidation of NADH to NAD cofactor strictly follows the enzymatic kinetics with high catalytic rate and strong affinity. The catalytic mechanism of CuxO NRs was that in the presence of hydrogen peroxide, the catalytic oxidizing NADH to NAD + involving with O2.-.anion production, making it realistic to mutually convert between coenzymes. Considering that the mutual transformation of NADH/NAD cofactors plays an important role in biological function, combination of CuxO NRs with alcohol dehydrogenase, a highly selective method for fluorimetric detection of ethanol was established. The as-proposed sensing platform is capable of dectecting alcohol with the limit of detection of 26.7 µM (S/N = 3) and applied in practical sample with satisfied accuracy and recovery. The as-developed regenerable NADH peroxidase mimics would also cast lights in biocatalysis, synthetic biology and bioenergy.


Assuntos
Etanol , Nanotubos , Fluorometria , Peroxidases
18.
Zhongguo Zhong Yao Za Zhi ; 46(20): 5310-5313, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34738434

RESUMO

The present study investigated the chemical constituents of Caesalpinia decapetala in the Fabaceae family. The chemical constituents were isolated and purified by chromatographies with silica gel, RP-C_(18), Sephadex LH-20, and preparative HPLC, and their structures were determined based on the spectroscopic data and physicochemical properties, as well as relevant references. Three pairs of new dibenzoxocin derivatives were isolated from 70% ethanol extract of C. decapetala and identified as protosappanoside A(1 a), isoprotosappanoside A(1 b), protosappanoside B(2 a), isoprotosappanoside B(2 b), protosappanoside C(3 a), and isoprotosappanoside C(3 b), respectively.


Assuntos
Caesalpinia , Cromatografia Líquida de Alta Pressão , Etanol , Estrutura Molecular , Extratos Vegetais
19.
Anal Chem ; 93(45): 15015-15023, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34730329

RESUMO

The onset of Covid-19 pandemic has resulted in the exponential growth of alcohol-based hand rub (ABHR)/hand sanitizer use. Reports have emerged of ABHR products containing methanol, a highly toxic compound to humans, exposing users to acute and chronic medical illnesses. While gas chromatography-mass spectrometry (GC-MS) remains the gold-standard method for the detection and identification of impurities in ABHRs, there exist limitations at widespread volume testing. This paper demonstrates the capability of an inexpensive portable pyroelectric linear array infrared spectrometer to rapidly test ABHR and compare the performance with a benchtop Fourier transform infrared spectrometer and HS-GC-MS. Multicomponent partial least square quantification models were built with performance found to be comparable between the two spectrometers and with the HS-GC-MS. Furthermore, the portable spectrometer was field-tested with real-world samples in Malaysia on both retail products (Group A) and freely deployed public dispensers (Group B) between May and November 2020. A total of 386 samples were tested. Only 75.2% of Group A met the criteria of safe and effective ABHR [no detectable methanol and alcohol concentration above 60% (v/v)], while <50% of Group B did. In addition, 7.4 and 18.8% of Group A and Group B, respectively, were found to contain methanol above permissible limits. The high percentage of sub-standard and methanol-containing samples combined with the frequent use of ABHR by the public highlights the need for and importance of a portable and rapid testing device for widespread screening of ABHR against falsified products and protects the general public.


Assuntos
COVID-19 , Higienizadores de Mão , Etanol , Humanos , Pandemias , Saúde Pública , SARS-CoV-2
20.
Environ Sci Process Impacts ; 23(11): 1688-1695, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34734218

RESUMO

The biotransformation of 6:2 fluorotelomer alcohol (6:2 FTOH) results in the production of bioactive and persistent metabolites, including perfluorinated carboxylic acids (PFCAs). While the products of 6:2 FTOH metabolism have been elucidated in several animal models, the responsible cytochrome P450 (CYP) isoform(s) have not been reported. Here, we characterized the in vitro oxidation of 6:2 FTOH using human liver microsomes and recombinant human CYPs. Six major xenobiotic metabolizing CYPs were screened for their capacity to catalyze 6:2 FTOH oxidation using chemical inhibitors selective towards CYP isoforms. Of the CYP isoforms investigated, CYP2A6 was the only enzyme capable of catalyzing 6:2 FTOH in human liver microsomes, with KM and Vmax values of 4076 ng mL-1 and 69 ng mL-1 min-1, respectively. We further probed the metabolic mechanism by plotting the 6:2 FTOH kinetic profile and extrapolating data to several possible kinetic models. 6:2 FTOH oxidation followed the typical one-site Michaelis-Menten kinetic model. This study also reports that 6:2 FTOH loss is associated with active CYP2A6 by incubating microsomes with the selective CYP2A6 inhibitor tranylcypromine, which bound competitively to the enzyme as determined by an increased KM (8796 ng mL-1) but unchanged Vmax value. Collectively, these findings provide a mechanistic perspective on the potential importance of CYP2A6 in the metabolic activation and phase I elimination of 6:2 FTOH and indirect human exposure to PFCAs.


Assuntos
Sistema Enzimático do Citocromo P-450 , Microssomos Hepáticos , Animais , Biotransformação , Citocromo P-450 CYP2A6/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Etanol/metabolismo , Humanos , Microssomos Hepáticos/metabolismo , Oxirredução
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