Methanol Levels Research Articles

Application of 1-octanol in the extraction and GC-FID analysis of volatile organic compounds produced in biogas and biohydrogen processes

Information about the volatile organic compounds generated in biogas and hydrogen production bioreactors is essential to elucidate the metabolic routes and varying yields of CH4 and H2 processes. In this work, the determination of 12 compounds (acetone, methanol, ethanol, 1-propanol, 1-butanol, and acetic, propanoic, butyric, isovaleric, valeric, caproic, and lactic acids) was performed by gas chromatography, after a vortex-assisted liquid–liquid microextraction (VALLME) procedure using 1.2 mL of crude sample and 400 µL of 1-octanol. Optimization of the separation process was performed, considering the solvent viscosity. The analytical curves were validated using ANOVA, demonstrating satisfactory precision and accuracy. Selectivity was confirmed by GC–MS analysis, which allowed the detection of glycerol, 1,3-propanediol, and 1,3-butanediol in some samples. Methanol levels exceeded the upper limit of quantification, with acetic acid and ethanol being the predominant compounds in the analyzed reactors. An additional investigation was conducted to assess potential interferences for lactic acid. The developed method employs a biodegradable extraction solvent, without any need for a dispersing solvent, and involves a single chromatographic run, without any derivatization steps.

Response of anammox to organics with different degradation characteristics and exposure time: Performance, sludge characteristics and bacterial community

The effects of typical organic compounds including easily degradable organic matters sodium acetate, yeast and methanol, and refractory organic matter (ROM) humic acid on anaerobic ammonium oxidation (anammox) systems in short-term and medium-term exposure time were studied. During short-term experiments, nitrogen removal activity (NRA) was inhibited at sodium acetate level of 150 mg L−1 total organic carbon (TOC) and methanol level of 30–150 mg L−1 TOC, but humic acid and yeast (≤150 mg L−1 TOC) enhanced nitrogen removal in anammox systems. The greatest NRA of 30.10 mg TN g−1 VSS h−1 was recorded at yeast level of 90 mg L−1 TOC. In medium-term experiments, organics significantly inhibited the nitrogen removal ability. As a ROM, humic acid enhanced sludge aggregation and biological diversity, but decreased the bioactivity and extracellular polymeric substances levels. Due to the endogenous denitrification, the relative abundance of anammox bacteria (AnAOB) was decreased. Candidatus Kuenenia is still dominant in sludge with methanol and humid acid, but AnAOB are not dominant due to the addition of sodium acetate and yeast. This research would be beneficial for the full-scale application of the anammox process in treating real wastewater with organics and ammonia.

Substances of health concern in home-distilled and commercial alcohols from Texas

ObjectivePoor distillation practices in the production of spirits have historically resulted in many instances of adverse health outcomes including death. Concern has focused on lead and copper contamination as well as unhealthy levels of methanol and glyphosate. This study assesses home-distilled and commercially distilled alcohols from Texas for these substances of concern, highlighting their potential risks to public health. MethodsAtomic absorption spectroscopy, gas chromatography, and enzyme-linked immunosorbent assay were employed to determine lead and copper, methanol, and glyphosate levels in 12 commercial and 36 home-distilled alcohol samples. ResultsOur findings showed that 11 % of the home-distilled alcohols exceeded the U.S. Alcohol and Tobacco Tax and Trade Bureau's copper safety limits of 0.5 mg/L for wine. Additionally, 36 % of these samples surpassed the European Commission (EC)'s lead legal threshold of 0.15 mg/L set for wine products. Results from commercial alcohols indicated that no samples exceeded the same safety limits for copper, and 33 % exceeded the same legal threshold for lead. Both commercial and home-distilled alcohols exhibited methanol concentrations remarkably below the 0.35 % limit for brandy set by the U.S. Food and Drug Administration. Only two home-distilled samples contained detectable glyphosate concentrations well below 100 μg/L, the maximum residue level in beer and wine established by the EC. ConclusionsOur findings suggested that consumption of alcohol in Texas may pose potential health risks associated with the elevated content of lead and copper. There is a need for increased focus on alcohol as a potential source of exposure to heavy metals.

Simultaneous determination of methanol, ethanol, and formic acid in human serum by HSGC-MS: Method development, validation, and application

The concurrent assessment of methanol, ethanol, and formic acid is imperative for accurate clinical toxicology diagnosis in cases of methanol poisoning. Here, we reported a very simple and reliable headspace gas chromatography coupled with mass spectrometry (HSGC-MS) method for simultaneous quantitative determination of methanol, ethanol and formic acid in blood samples. The derivatization variables for formic acid were optimized. The method exhibits high sensitivity, good selectivity and effective separation factor for methanol (6.51 min), ethanol (8.29 min), and formic acid (11.41 min). The method demonstrates excellent reproducibility and accuracy. The limit of detection (LOD) and the limit of quantification (LOQ) were determined to be 3.14–5.83 μg/mL and 10.47–19.34 μg/mL, respectively. Finally, this method was successfully used for measuring the levels of methanol, ethanol, and formic acid in the serum of patients involved in actual methanol poisoning incidents.

Analysis of Methanol and Ethanol Content in Illegal Alcoholic Beverages using Headspace Gas Chromatography: Case Studies at Rwanda Forensic Institute

Illegal alcoholic production in Rwanda has become a critical social concern due to its widespread prevalence and associated health risks, stemming from the inexpensive distillation process employed by illicit producers. This often results in the unintentional production of toxic methanol instead of safe ethyl alcohol, presenting a substantial hazard in the context of illegal alcohol production. Methanol, when consumed, transforms into toxic formic acid in the body, causing severe health complications by disrupting mitochondrial respiration. Between 2021 and 2022, 183 forensic cases related to methanol and ethanol poisoning were collected nationwide and examined at the Rwanda Forensic Institute (RFI). Utilizing Headspace Gas Chromatography, the study aimed to quantitatively assess the extent of the problem and compare results to Rwanda’s allowable limits for methanol and ethanol in alcoholic beverages. The analysis demonstrated a significant variation in ethanol content (3.8% to 98.9% v v-1) and methanol levels (32% to 58.3% v v-1), with 6.6% of samples exceeding the methanol limit (0.5% v v-1) and 16.9% surpassing the ethanol limit (45% v v-1). The City of Kigali emerged as the primary contributor to non-compliance, notably associated with specific brands like K’bamba, African Buffalo, Merry Cane, Royal Castle, and unbranded alcoholic beverages. Importantly, none of the samples tested positive for both methanol and ethanol simultaneously, emphasizing the urgency of monitoring and regulating Rwanda’s alcoholic beverages market to ensure compliance with acceptable methanol and ethanol levels and safeguard public health.

Controlling the stability and adhesion performance of cold-setting phenol–resorcinol–formaldehyde resin adhesives through methanol addition

Phenol–resorcinol–formaldehyde (PRF) resin adhesives are commonly used in the manufacture of laminated timber products, and they are cold-set at room temperature rather than hot-pressed to generate a three-dimensional polymer structure in the products. However, their excellent reactivity often leads to poor storage stability and a short pot life. This study examines the influence of methanol addition on the stability and adhesion performance of PRF resins. These resins were synthesized by various levels of methanol addition (5 %, 10 %, and 15 %), and their structures were investigated using Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies. Furthermore, differential scanning calorimetry (DSC) was used to analyze their thermal behavior, and their cure kinetics were analyzed with two isoconversional analyses: Kissinger–Akahira–Sunose (KAS) and Vyazovkin (VYZ) method. The adhesion performances of PRF resins were evaluated for glue-laminated timber (GLT). The results demonstrated that the viscosity and solids content of PRF resins decreased while their gelation time increased as the methanol addition level increased. Methanol addition has also improved the resin stability over time. The chemical structure of PRF resins did not change considerably with an increase in the methanol level. However, methanol interaction with formalin in a hardener presumably hindered the reactivity of PRF resins. This was supported with an increase in the apparent activation energy of the curing process of PRF resins as the methanol level increased. In addition, decreasing the methanol levels from 15 % to 5 % enhanced the adhesion performance of GLT bonded with PRF resins. The results indicated that adding methanol to PRF resins improved its stability while simultaneously weakened its performance. However, 5 % methanol level is recommended for PRF resins.

Process Optimization for Production of Persimmon Wine with Lower Methanol.

Persimmon wine has various nutritional elements and high commercial potential. However, the high content of methanol, which is derived from the fruit's pectin, always hinders persimmon wine production. To reduce the methanol level in the wine, the effects of persimmon cultivar, starter, pectinase, and pretreatment methods were investigated via single-factor and orthogonal experiments. The persimmon cultivar 'MaoKui' was finally used throughout the study owing to its lowest pectin concentration (24.5 g/kg). The best treatment conditions against the persimmon pulp were pectinase (0.04 g/kg) at 30 °C for 4 h, then boiled at 115 °C for 15 min before fermentation started. The optimized fermentation conditions for wine production were pectinase (0.03 g/kg), 250 mg/kg starter (BO213 and SPARK with equal amounts), at 28 °C for 6 d. The obtained wine had 77.7 mg/L methanol and a 68.4% raw juice yield. The fruit wine had 111.4 mg/L methanol and a 90.6 sensory evaluation score. Forty-nine volatile aromas were identified. Ethyl acetate content was the highest, followed by 3-methyl-1-butanol, 2,3-butanediol, and lactate ethyl ester. The persimmon wine had a unique style with transparent color, elegant aroma, and pure taste.

Dysbiotic Vaginal Microbiota Induces Preterm Birth Cascade via Pathogenic Molecules in the Vagina.

Dysbiotic vaginal microbiota (DVM) disturb the vaginal environment, including pH, metabolite, protein, and cytokine profiles. This study investigated the impact of DVM on the vaginal environment in 40 Korean pregnant women and identified predictable biomarkers of birth outcomes. Cervicovaginal fluid (CVF) samples were collected in the third trimester using vaginal swabs, examined for pH, and stored at -80 °C for further analysis. The samples were grouped as full-term (FTB, n = 20) and preterm (PTB, n = 20) births. The microbiota was profiled in the V1-V9 regions. The levels of targeted metabolites, TLR-4, and cytokines were determined. The pH of CVF from PTB (>4.5) was significantly higher than that of the CVF from FTB (>3.5) (p < 0.05). Neonatal gestational age at delivery, birth weight, and Apgar score differed significantly between groups. The relative abundances of beneficial Lactobacillus spp., such as Lactobacillus gasseri, Lactobacillus jensenii, and Bifidobacterium, were higher in FTB, whereas those of pathogenic Enterococcus faecalis, Staphylococcus, Prevotella, Ureaplasma parvum, and Corynebacterium spp. were higher in PTB. Acetate, methanol, TLR-4, and TNF-α levels were negatively correlated with gestational age at delivery and birth weight. Moreover, ethanol, methanol, TLR-4, IL-6, IL-1β, and TNF-α levels were positively correlated with succinate, acetate, acetoacetate, formate, and ammonia. Overall, DVM induces preterm birth via pathogenic molecules in the vagina.

Efficacy of Citrullus colocynthis seed extract on Earias vittella, Fabricius, (Lepidoptera: Noctuidae): environment sustainable approach.

Earias vittellaFabricius, 1794 (Noctuidae: Lepidoptera) is deliberated to be one of the most destructive pests of cotton and okra vegetation in the world including Asia. The pest has established resistance to various synthetic insecticides. The use of bio-pesticide is one of the unconventional approaches to develop a vigorous ecosystem without harming non- target pests and beneficial natural insect fauna. In the present study, the toxicity levels of Citrullus colocynthis seed extract have been evaluated against the populations of E. vittellaunder standardized laboratory conditions. The toxic effects of C. colocynthis on development periods, protein contents and esterase activity of the life stages of E. vittella were also evaluated. The toxicity levels of methanol, ethanol, hexane, water and profenofos were evaluated on the 1st instar larvae of E. vittella. LC30 and LC80 concentrations exhibited the effectiveness of methanol-based C. colocynthis seed extract against 1st instar larvae of E. vitella. The enhanced larval and pupal periods were revealed in treated samples during the comparison with untreated samples. The intrinsic rate of increase, net reproductive rate in the LC30 and LC80 concentrations exposed larvae remained less than the control treatment. Fecundity, the esterase activity and protein contents were declined in LC30 and LC80 treated samples as compared to the control. The present findings suggest that C. colosynthis extracts based botanical insecticides are beneficial, ecosystem sustainable and can be integrated with insect management programs from environment safety perspective.

Learning algorithms for identification of whisky using portable Raman spectroscopy

Reliable identification of high-value products such as whisky is vital due to rising issues of brand substitution and quality control in the industry. We have developed a novel framework that can perform whisky analysis directly from raw spectral data with no human intervention by integrating machine learning models with a portable Raman device. We demonstrate that machine learning models can achieve over 99% accuracy in brand or product identification across twenty-eight commercial samples. To demonstrate the flexibility of this approach, we utilized the same algorithms to quantify ethanol concentrations, as well as measuring methanol levels in spiked whisky samples. To demonstrate the potential use of these algorithms in a real-world environment we tested our algorithms on spectral measurements performed through the original whisky bottle. Through the bottle measurements are facilitated by a beam geometry hitherto not applied to whisky brand identification in conjunction with machine learning. Removing the need for decanting greatly enhances the practicality and commercial potential of this technique, enabling its use in detecting counterfeit or adulterated spirits and other high-value liquids. The techniques established in this paper aim to function as a rapid and non-destructive initial screening mechanism for detecting falsified and tampered spirits, complementing more comprehensive and stringent analytical methods.

Intracranial Bleeding in Methanol Intoxication Case

Methyl alcohol, which is mostly used in the industrial sector, is also widely used in our country to obtain cheap drinks. It is a colorless, volatile liquid with a distinctive odor. Even 8-10 ml of methanol taken into the body from outside is toxic. Approximately 25-30 ml of methanol can cause poisoning that can lead to permanent blindness. The best method for the definitive diagnosis of methyl alcohol poisoning is to measure the methanol level in the blood. Patients may develop headache, central nervous system depression, coma and seizure. Imaging is recommended in patients with altered consciousness. Putaminal necrosis and intracranial hemorrhage (SAH, putaminal intraparenchymal hemorrhage) may develop in these patients. Our case is a 50-year-old male patient with a history of constant homemade alcohol consumption. The patient was brought with complaints of visual impairment and confusion after drinking alcohol. Basal ganglia hemorrhage was detected on the patient's cranial tomography. The patient, who was admitted to intensive care, deteriorated and died on the 4th day of his treatment. Morbidity and mortality rates can be very high in patients presenting with suspected methanol intoxication. Therefore, we wanted to emphasize the importance of early diagnosis and treatment.

Evaluating the combustion characteristics of methanol-gasoline blends in IC engines

This study expresses the core elements associated with the various types of fuels used in vehicles functional in the present day. The exploration of chemicals such as methanol and others have also been conducted in an accurate manner to gain objective insights and outlooks in the study. The social and economic impacts of methanol-gasoline blends in engines can be complex in nature that depend on various factors such as the concentration levels of methanol in the blend, the availability of fuel, and public perception, among others. Further research and analysis as conducted in the study have been useful in understanding the potential impacts of methanol-gasoline blends across global spheres.

Characteristics and sources of oxygenated VOCs in Hong Kong: Implications for ozone formation

To investigate the characteristics of oxygenated volatile organic compounds (OVOCs) and their potential contribution to ozone (O3) generation, we conducted 3-h high-resolution observations during the summertime of 2022 and the wintertime of 2021. This study focused on a total of 28 OVOCs in five different chemical classes, which were encompassed at two representative sites in Hong Kong, including a roadside and an urban area. During the summertime, the total concentrations of quantified OVOCs (∑OVOCs) were 45 ± 12 and 63 ± 20 μg m−3 at the roadside and urban sites, respectively, whereas the ∑OVOCs decreased by 31 ± 11 % and 38 ± 13 %, respectively, during the wintertime. Among the classes of OVOCs, carbonyls and alcohols were the two predominant at both sites, with relatively higher concentration levels of acetone, methanol, butanaldehyde, and acrolein. The sources of OVOCs have significant spatial and temporal characteristics. Spatially, OVOCs were predominately attributed to primary emission and background at the roadside site, whereas they were a combination of primary emission, secondary formation, and background at the urban site. Temporally, background sources dominated the summertime OVOCs, while the contribution of primary emissions increased for the wintertime OVOCs. The O3 formation potential (OFP) for the OVOCs was calculated. The OFPs were 67 ± 16 and 119 ± 31 μg m−3 at the roadside and urban sites during the summertime, whereas the winter OFPs declined 30 % at the roadside and 38 % at the urban site. The background sources of carbonyls and alcohols at the roadside and of carbonyls and acrylates in the urban area were the major contributors to the summer OFP. Controlling the OVOC sources from local non-combustion sources such as gasoline-fuel evaporation and volatile chemical-containing products could lead to a reduction of OVOCs in the background and subsequently mitigate the OFP. This is beneficial for local O3 reduction in Hong Kong and surrounding regions.

Enhanced production of human interferon α2b in glycoengineered Pichia pastoris by robust control of methanol feeding and implications of various control strategies

Interferon α2b (IFNα2b), a prominent cytokine molecule, is bestowed with immunomodulatory, antiproliferative, and antiviral properties. Like any other recombinant protein produced in methylotrophic yeast Pichia pastoris, Human interferon α2b (huIFN α2b) production in P. pastoris depends on methanol utilization during the induction phase. This study investigates the impact of varying residual methanol concentrations on huIFNα2b productivity and assesses control strategies towards the tight control of residual methanol concentration in fed-batch experiments carried out in the fermentation calorimeter. Real-time monitoring of P. pastoris metabolism was facilitated by metabolic heat rate measurements and exhaust gas analyser. Optimal methanol concentration screening performed at different concentrations viz., 1.5, 3, 5, and 7 g/L, revealed the highest huIFNα2b productivity at 3 g/L (0.21 mg/g h). Methanol sensor provided input data for three different control strategies (on/off, proportional integral (PI), and model-based adaptive PI) to maintain optimal methanol levels (3 g/L). Model-based adaptive control resulted in the highest huIFNα2b yield, productivity (244.34 mg/L, 0.31 mg/g h), surpassing on/off (188.7 mg/L, 0.16 mg/g h) and PI (202.3 mg/L, 0.28 mg/g h) control strategies. The model-based adaptive PI control framework developed in this study could be employed for other heterologous protein production in P. pastoris.

The Use of a Droplet Collar Accessory Attached to a Portable near Infrared Instrument to Identify Methanol Contamination in Whisky.

The aim of this study was to evaluate the ability of a droplet collar accessory attached to a portable near-infrared (NIR) instrument to characterize the artificial contamination of methanol in commercial whisky samples. Unadulterated samples (n = 12) were purchased from local bottle shops where adulterated samples were created by adding methanol (99% pure methanol) at six levels (0.5%, 1%, 2%, 3%, 4% and 5% v/v) to the commercial whisky samples (controls). Samples were analyzed using a drop collar accessory attached to a MicroNIR Onsite instrument (900-1650 nm). Partial least squares (PLS) cross-validation statistics obtained for the prediction of all levels of methanol (from 0 to 5%) addition were considered adequate when the whole adulteration range was used, coefficient of determination in cross-validation (R2cv: 0.95) and standard error in cross of validation (SECV: 0.35% v/v). The cross-validation statistics were R2cv: 0.97, SECV: 0.28% v/v after the 0.5% and 1% v/v methanol addition was removed. These results showed the ability of using a new sample presentation attachment to a portable NIR instrument to analyze the adulteration of whisky with methanol. However, the low levels of methanol adulteration (0.5 and 1%) were not well predicted using the NIR method evaluated.

Rotational excitation of methanol in collisions with molecular hydrogen

ABSTRACT This paper presents rate coefficients for transitions between rotational levels of the A-type and E-type nuclear spin modifications of methanol induced by collisions with molecular hydrogen. These rate coefficients are required for an accurate determination of methanol abundance in the interstellar medium, where local thermodynamic equilibrium conditions generally do not apply. Time-independent close-coupling quantum scattering calculations have been employed to calculate cross-sections and rate coefficients for the (de-)excitation of methanol in collisions with para- and ortho-H2. These calculations utilized a potential energy surface (PES) for the interaction of methanol with H2 recently computed by the explicitly correlated CCSD(T)-F12a coupled-cluster method that employed a correlation-consistent aug-cc-pVTZ basis. Rate coefficients for temperatures ranging from 3 to 250 K were calculated for all transitions among the first 76 rotational levels of both A-type and E-type methanol, whose energies are less than or equal to 170 K. These rate coefficients are compared with those by Rabli and Flower who carried out coupled-state calculations using a PES computed by second-order many-body perturbation theory. Simple radiative transfer calculations using the present set of rate coefficients are also reported and compared with such calculations using the rate coefficients previously computed by Rabli and Flower.

Gut ecological networks reveal associations between bacteria, exercise, and clinical profile in non-alcoholic fatty liver disease patients.

Gut microbial dysbiosis has been observed in non-alcoholic fatty liver disease (NAFLD). The beneficial impact of exercise, the recommended lifestyle change for NAFLD patients, might be mediated by the gut microbiome (GM). However, the exact taxonomic and functional signatures associated with the host's clinical and biochemical improvement during exercise in NAFLD patients have not been elucidated yet. To investigate the impact of exercise on GM and reveal GM structures associated with NAFLD improvement during exercise. Stool samples from a 12-week randomized controlled exercise study on NAFLD subjects (N = 39) were retrieved, and shotgun metagenomics was performed at baseline and endpoint. Differential correlation network and enrichment analysis were applied to characterize the GM taxonomic and functional changes during the exercise intervention and to associate GM changes with biomarkers of liver status and metabolic dysregulation. Network analysis demonstrated that exercise induced significant changes in the bacterial interactome, which were associated with waist circumference; resting metabolic rate; plasma fasting concentrations of triglyceride, glucose, insulin, and glycated hemoglobin A1c; and homeostasis model assessment for insulin resistance. Grouping the patients in the exercise group (N = 20) as responders (N = 13) and non-responders (N = 7) using their intrahepatic lipid content (IHL) change allowed us to identify bacteria consortia contributing to the levels of alanine fermentation, methanol-, creatinine-, and protocatechuate degradation and as a result to the plasma concentrations of liver injury markers alanine transaminase, gamma-glutamyl transaminase, and aspartate transaminase. We showed that even though exercise has not a significant impact on the alpha- and beta-diversity of NAFLD patients, it leads to a significant re-structuring of the gut bacteria interactome and that specific structural changes can be linked with improvements in IHL. IMPORTANCE Our study is applying a community-based approach to examine the influence of exercise on gut microbiota (GM) and discover GM structures linked with NAFLD improvements during exercise. The majority of microbiome research has focused on finding specific species that may contribute to the development of human diseases. However, we believe that complex diseases, such as NAFLD, would be more efficiently treated using consortia of species, given that bacterial functionality is based not only on its own genetic information but also on the interaction with other microorganisms. Our results revealed that exercise significantly changes the GM interaction and that structural alterations can be linked with improvements in intrahepatic lipid content and metabolic functions. We believe that the identification of these characteristics in the GM enhances the development of exercise treatment for NAFLD and will attract general interest in this field.

Fermentative microbiota and chemical characterization of traditional date vinegar with promising biotechnological applications

IntroductionThe indigenous microbiota of traditional date vinegar is inadequately reported in the literature, yet its understanding is necessary for the industrial development of this product. This study aimed to perform microbiological and chemical analyses of traditional date vinegar.MethodsForty home-made samples (HMS) and laboratory-made samples (LMS) of date vinegar were analyzed. Escherichia coli, coliforms, and Enterobacteriaceae were enumerated using conventional plate methods to evaluate the hygienic quality. Bacteria and yeasts were identified by polymerase chain reaction. Acetic acid, ethanol, and methanol contents were analyzed by headspace gas chromatography.Results and DiscussionEscherichia coli was not detected in any sample. Coliforms and Enterobacteriaceae occurred in 75 and 67% of HMS, respectively, and in 3.6% (both groups) of LMS. The LMS had better hygienic quality and supported better growth of yeasts and AAB than the HMS. Thirty-five yeasts belonged to 6 genera and 55 acetic acid bacteria (AAB) to 5 Gluconobacter species. The highest content of ethanol correlated with the presence of Saccharomyces cerevisiae. Gluconobacter japonicus and Gluconobacter oxydans tolerated 7.5% ethanol. Gluconobacter frateurii survived at pH 2.59. The percentage of acetic acid was less than the international recommended standard levels and ranged from 0.09% to 3.38%, and 0.03% to 3.46% in HMS, and LMS, respectively. The content of ethanol ranged from 0.14% to 2.17%, and 0.07% to 7.81% in HMS, and LMS, respectively. Methanol was less in LMS (≤ 0.06%) than in HMS (≤ 0.17%). Utilizing the traditional method for producing date vinegar does not assure the production of true and safe vinegar that contains the specified levels of acetic acid and ethanol. It may also contain unacceptable levels of the toxic chemical methanol. However, a high microbial diversity of yeasts and Gluconobacter spp. was identified which indicates the potential of producing a high-quality and safe product by modifying the production process possibly by using the isolated yeasts and AAB as starter cultures.

Outcome of Methanol Toxicity Outbreak In Saudi Arabia: Case Series Study.

Introduction Methanol poisoning is an acute medical emergency. If not recognized in time and treated properly, it can lead to a considerable magnitude of morbidity as well as mortality. This article aims to report cases of methanol toxicity, focusing on clinical presentation, management, and outcomes. Method Nine ICU-admitted patients with confirmed positive serum methanol levels wereanalyzed in a case series at King Fahad General Hospital in Jeddah, Saudi Arabia, between November 2022 and January 2023. Results Among the nine patients admitted to the ICU due to methanol poisoning, the majority were middle-aged males, with two females included. Gastrointestinal symptoms were seen in two-thirds of patients, while three patients required immediate mechanical ventilation due to a low Glasgow Coma Scale. Severe metabolic acidosis was observed in most cases. All patients received sodium bicarbonate and hemodialysis, with six patients also receiving fomepizole. However, two patients in the study with low initial low Glasgow Coma Scale (GCS), severe metabolic acidosis, and diffuse brain edema, did not survive. One patient reported acute complete vision loss. Conclusion This case series highlights the importance of promptly recognizing and managing methanol toxicity in ICU settings. The clinical presentation of methanol toxicity can be challenging, and early diagnosis and treatment are crucial to prevent irreversible damage.

Case Reports Study on Methanol Poisoning in King Abdul Aziz Specialist Hospital, Taif, Saudi Arabia

Methanol poisoning is a challenging issue due to its inducing acute multiple organ failures, and especially due to a lack of preparedness, available antidotes, and management protocols. The current study presents six cases of methanol poisoning that attended the emergency department of King Abdul Aziz Specialist Hospital, Taif, Saudi Arabia, between March and November 2022. All of the patients suffered from severe metabolic acidosis and visual impairment following the ingestion of homemade alcoholic beverages and colonia. Three patients were comatose, suffered from post-cardiac pulmonary arrest, and, finally, died, while the other three were non-comatose and discharged from the ICU after improvement. Management was based on clinical symptoms and other laboratory findings due to a shortage of methanol level measurement resources. The antidote, fomepizole, was not given to all of the cases due to its deficiency, and ethanol was given only to one patient due to difficulties in administering it without monitoring its concentration. Methanol poisoning and its outbreak provide insights into the dangers of hazardous homemade alcohol and other pharmaceutical preparations that might be adulterated with methanol, particularly to the shortage of suitable diagnostic testing and antidotes in addition to poor resources for management of intoxicated patients in some regions of Saudi Arabia.