Trimethylamine Research Articles

MnN4 embedded zeolite-templated carbon for methylamine and trimethylamine sensing: Insights from DFT study

From the perspective of raw material losses and human health, monitoring fish-based food quality has become more prominent. As a nondestructive technology, gas sensors have received extensive attention for evaluating the freshness of fish. In this study, the sensing and electronic properties of methylamine (MA) and trimethylamine (TMA) molecule adsorption on MnN4 embedded zeolite templated carbon (MnN4-C) were studied by density functional theory (DFT) method. The results show that the MnN4-C exhibits good structural stability, and displays high sensitivity toward MA and TMA gases by analysis of the interaction distance, adsorption energy, charge transfer and sensing response. It is worth noting that the ambient humidity has demonstrated no effect on the gas-sensing properties of MnN4-C for the studied gases. Meanwhile, applying a positive electric field can increase the adsorption energy and charge transfer, which enhances the MA and TMA gas sensitivity of MnN4-C. The recovery time reveals that MnN4-C can be an excellent reusability sensor for MA and TMA gases. This study provides theoretical direction for exploring the sensing application of MnN4-C in evaluating freshness of fish.

Inhibition of Food-Borne Pathogen Growth and Biogenic Amine Synthesis by Spice Extracts

Food-borne pathogens and their toxins cause significant health problems in humans. Formation of biogenic amines (BAs) produced by microbial decarboxylation of amino acids in food is undesirable because it can induce toxic effects in consumers. Therefore, it is crucial to investigate the effects of natural additives with high bioactivity like spice extracts to inhibit the growth of these bacteria and the formation of BAs in food. In the present study, the antibacterial effects of diethyl ether spice (sumac, cumin, black pepper, and red pepper) extracts at doses of 1% (w/v) on Gram-positive (Staphylococcus aureus and Enterococcus faecalis) and Gram-negative (Klebsiella pneumoniae, Pseudomonas aeruginosa, Campylobacter jejuni, Aeromonas hydrophila, Salmonella Paratyphi A, and Yersinia enterocolitica) food-borne pathogen bacterial strains (FBP) were established. In addition, the accumulation of ammonia (AMN), trimethylamine (TMA), and biogenic amines (BAs) in tyrosine decarboxylase broth (TDB) was investigated by using high performance liquid chromatography (HPLC). Sumac extract exhibited the highest antibacterial potential against all FBPs, followed by cumin and peppers. AMN (570.71 mg/L) and TMA (53.66 mg/L) production were strongly inhibited by sumac extract in the levels of 55.10 mg/L for Y. enterocolitica and 2.76 mg/L for A. hydrophila, respectively. With the exception of S. aureus, black pepper dramatically reduced the synthesis of putrescine, serotonin, dopamine, and agmatine by FBP especially for Gram-negative ones. Furthermore, sumac extracts inhibited histamine and tyramine production by the majority of FBP. This research suggests the application of sumac extracts as natural preservatives for inhibiting the growth of FBPs and limiting the production of AMN, TMA, and BAs.

Assembly-Induced Emission of Copper Nanoclusters: Revealing the Sensing Mechanism for Detection of Volatile Basic Nitrogen in Seafood Freshness On-Site Monitoring.

Total volatile basic nitrogen (TVB-N) is a vital indicator for assessing seafood freshness and edibility. Rapid on-site detection of volatile basic nitrogen (VBN) is of significant importance for food safety monitoring. In this study, highly luminescent self-assembled copper nanoclusters (Cu NCs@p-MBA), synthesized using p-mercaptobenzoic acid (p-MBA) as the ligand, were utilized for the sensitive detection of VBNs. Under acidic conditions, Cu NCs@p-MBA formed compact and well-organized nanosheets through noncovalent interactions, accompanied by intense orange fluorescence emission (651 nm). The benzene carboxylic acid part of Cu NCs@p-MBA provided the driving force for supramolecular assembly and exhibited a strong affinity for amines, particularly low-molecular-weight amines such as ammonia (NH3) and trimethylamine (TMA). The quantitative determination of NH3 and TMA showed the detection limits as low as 0.33 and 0.81 ppm, respectively. Cu NCs@p-MBA also demonstrated good responsiveness to putrescine and histamine. Through density functional theory (DFT) calculations and molecular dynamics (MD) simulations, the precise atomic structure, assembly structure, luminescent properties, and reaction processes of Cu NCs@p-MBA were studied, revealing the sensing mechanism of Cu NCs@p-MBA for highly sensitive detection of VBNs. Based on the self-assembled Cu NCs@p-MBA nanosheets, portable fluorescent labels were developed for semiquantitative, visual, and real-time monitoring of seafood freshness. Therefore, this study exemplified the high sensitivity of self-assembly induced emission (SAIE)-type Cu NCs@p-MBA for VBNs sensing, offering an efficient solution for on-site monitoring of seafood freshness.

Effects of slightly acidic electrolyzed water combined with ԑ-polylysine-chitooligosaccharide Maillard reaction products treatment on the quality of vacuum packaged sea bass (Lateolabrax japonicas)

In this study, a new natural preservative, ε-polylysine (ε-PL) and chitooligosaccharides (COS) Maillard reaction products (LC-MRPs), was prepared by Maillard reaction. The preservation effect of LC-MRPs combined with slightly acidic electrolyzed water (SAEW) pretreatment (SM) on vacuum-packed sea bass during refrigerated storage was evaluated. The results showed that after 16 days, SM treatment could effectively inhibit the microbial growth and prevent water migration in sea bass. In addition, the highest water holding capacity (69.79 %) and the best sensory characteristics, the lowest malonaldehyde (MDA) (58.96 nmol/g), trimethylamine (TMA) (3.35 mg/100 g), total volatile basic nitrogen (TVB-N) (16.93 mg N/100 g), myofibril fragmentation index (MFI) (92.2 %) and TCA-soluble peptides (2.16 μmol tyrosine/g meat) were related to SM group. Combined with sensory analysis, we can conclude that the combined treatment of SAEW and LC-MRPs could prolong the shelf-life of sea bass for another 11 days compared with the DW group. Results disclosed that the composite treatment of SAEW and LC-MRPs is a promising technology to improve the shelf-life of vacuum-packed sea bass during refrigerated storage.

Biphenyl-rGO composite room temperature gas sensor for enhanced amine sensing

Amines, which are classified as volatile organic compounds (VOCs), serve a variety of purposes in the fields of environmental monitoring, food safety, and healthcare diagnosis. The present technique for detecting amine levels involves sophisticated setups and bulky equipment. Here. In this study, a chemoresistive gas sensor is developed that is cost-effective and easy to operate at room temperature (RT). The sensor is designed specifically for the detection of Ammonia, dimethylamine (DMA), trimethylamine (TMA), and total volatile basic nitrogen (TVB-N). Using biphenyl-reduced graphene oxide (B-rGO) composite gas sensors effectively addresses the issues of low sensitivity-selectivity and long-term instability commonly observed in conventional amine sensors. B-rGO sensor produced sensitivity of ∼3500 and selectivity above 30 for TVB-N sensing. The sensor is stable for temperature fluctuations below 50 °C and shows stable sensing response for period of over 3 months. A Chemoresistive B-rGO sensor was developed using an ultrasonic spray deposition system with optimized flow rate of 50 mL/h. Rapid evaporation of solvent using hot plate has resulted in unique morphology for B-rGO film sensors. The highest sensitivity, ∼836, is obtained for 100 ppm of ammonia with ammonia > DMA > TMA as a sensitivity order. B-rGO showed almost seven times higher amine sensitivity than rGO which highlights the importance of biphenyl in the B-rGO composite. Sensor calibration curve has been presented in the study to understand change in the sensitivity of sensor with increasing analyte gas concentration. The calibration curve has an average R-squared value of 0.98.

Cardiovascular diseases: pathophysiological role of gut microbiota and new targets for treatment and prevention

Despite certain success achieved in therapy and prevention, cardiovascular diseases (CVD) continue to be the leading cause of death of the population worldwide. One of the main reasons for this is that the pathophysiological mechanisms of the development of atherosclerosis, a disease that underlies most clinical forms of CVD, have not been fully understood yet, and therapy based on well-known concepts of pathogenesis, including lipid, does not provide the desired results. In this regard, search and identification of new molecular targets and therapeutic approaches is an important objective of modern medical science. In this direction, a completely new metabolic pathway identified by researchers, that links lipid consumption, gut microbiota (GM) and development of atherosclerosis, deserves interest. Thus, for the first time it was shown that GM uses food choline, as well as carnitine (found in red meat) for synthesis of trimethylamine (TMA), which, in turn, is rapidly oxidized by liver flavin monooxidases (FMO) to trimethylamine oxide (TMAO), that causes the development of atherosclerosis. Mechanisms of proatherogenic effect of TMAO, which, taken together, involve stimulation of inflow and suppression of outflow of cholesterol from the cell, have also been established. Another pathway of GM influence on the development or progression of atherosclerosis, that links the presence of bacterial infection and the degree of atherosclerosis development, has also been identified. It is believed that in this case, bacterial liposaccharides (LPS) interact with low-density lipoproteins (LDL), as a result of which LDL turn into atherogenic oxidized LDL. The article discusses possible therapeutic strategies for prevention and treatment of coronary atherosclerosis associated with both decreased production of TMAO and elimination of TMA from the intestines, and regulation of microbial metabolism (inhibition of microbial enzymes that produce TMA), as well as change in the structure of GM towards increase in the proportion of microorganisms beneficial to the human body (unable to produce TMA).

Evaluation of the Feasibility of In Vitro Metabolic Interruption of Trimethylamine with Resveratrol Butyrate Esters and Its Purified Monomers.

Resveratrol (RSV), obtained from dietary sources, has been shown to reduce trimethylamine oxide (TMAO) levels in humans, and much research indicates that TMAO is recognized as a risk factor for cardiovascular disease. Therefore, this study investigated the effects of RSV and RSV-butyrate esters (RBE) on the proliferation of co-cultured bacteria and HepG2 cell lines, respectively, and also investigated the changes in trimethylamine (TMA) and TMOA content in the medium and flavin-containing monooxygenase-3 (FMO3) gene expression. This study revealed that 50 µg/mL of RBE could increase the population percentage of Bifidobacterium longum at a rate of 53%, while the rate was 48% for Clostridium asparagiforme. In contrast, co-cultivation of the two bacterial strains effectively reduced TMA levels from 561 ppm to 449 ppm. In addition, regarding TMA-induced HepG2 cell lines, treatment with 50 μM each of RBE, 3,4'-di-O-butanoylresveratrol (ED2), and 3-O-butanoylresveratrol (ED4) significantly reduced FMO3 gene expression from 2.13 to 0.40-1.40, which would also contribute to the reduction of TMAO content. This study demonstrated the potential of RBE, ED2, and ED4 for regulating TMA metabolism in microbial co-cultures and cell line cultures, which also suggests that the resveratrol derivative might be a daily dietary supplement that will be beneficial for health promotion in the future.

Compiling a versatile toolbox for inducible gene expression in Methanosarcina mazei.

Methanosarcina mazei is a model organism, providing a platform to explore methanoarchaeal regulation mechanisms on the transcriptional and translational level. This study investigates and evaluates various molecular tools to allow inducible gene expression in M. mazei. (i) The TetR/TetO system was utilized to induce expression of a designed antisense RNA directed against sRNA154 allowing to increase transcripts of asRNA154 (500-fold), resulting in a significant decrease of sRNA154 levels (tetracycline-induced knockdown mutant). Strong reduction of sRNA154 was further confirmed in the knockdown mutant by up to 50-fold decreased transcript levels of the genes nifH, glnK1 , and glnA1 , the stability of which is increased by sRNA154. (ii) For translational regulation, an RNA thermometer was designed and first-ever utilized in an archaeon, inserted into the 5'-untranslated region of a reporter gene, which showed enhanced protein expression upon a temperature shift from 30°C to 40°C. (iii) The long 5'-UTR of a trimethylamine (TMA)-inducible polycistronic mRNA was evaluated and studied as a potential genetic tool for induced gene expression on the translational level. However, we discovered TMA-dependent regulation occurs most likely on the transcript level. (iv) A new selection marker (nourseothricin resistance) was established for M. mazei using the streptothricin acetyltransferase gene. Taken together, our findings provide a foundation for future exploration of genetic regulation and inducible gene expression in M. mazei and other methanoarchaea, advancing genetic studies in these organisms and enhancing their potential for biotechnology applications.

Multi-metabolomics and intestine microbiome analysis: YZC extract ameliorates septic-ALI by modulating intestine microbiota to reduce TMAO/NLRP3 signaling

BackgroundSepsis causes inflammation in response to infection, often leading to acute lung injury (ALI). Yazhicao (Commelina communis L., YZC) is widely distributed in the global tropics and has good anti-respiratory inflammatory activity; however, the protection of YZC against septic-ALI has not been established. PurposeThe role of YZC in septic-ALI will be investigated in this study. Methods and resultsIn this study, YZC was shown to inhibit excessive inflammation and alleviate septic-ALI. Network pharmacology predicts that Quercetin, Acacetin and Diosmetin have the potential to serve as the pharmacological substance basis of YZC in alleviating septic-ALI. The metabolomics results indicated that YZC could improve the metabolic disorders caused by septic-ALI, which were mostly concerned with energy metabolism and amino acid metabolism, with Trimethylamine (TMA)/Trimethylamine N-oxide (TMAO) being potential small molecule metabolic markers for the clinical diagnosis and treatment of septic-ALI. YZC inhibits the initiation and progression of septic-ALI by controlling the TMA/TMAO metabolites. Our results also suggest that YZC protects the intestinal barrier from damage. Furthermore, our research indicated that YZC reduces TMAO synthesis by inhibiting TMA production through remodeling the intestine microbiota. We investigated the mechanism of YZC-mediated protection against septic-ALI and showed that YZC reduced the expression of proteins associated with NLRP3 inflammatory vesicles in the lung by inhibiting the expression of NF-κB. ConclusionThese results show that YZC inhibits the NF-κB/NLRP3 signaling pathway by regulating metabolic and intestinal flora disorders in septic-ALI mice to reduce TMAO synthesis. This study presents a theoretical groundwork for the advancement of novel medications and clinical use of YZC to enhance septic-ALI and furnishes a theoretical rationale for regulating intestinal microbiota as a therapeutic instrument to treat sepsis and septic-ALI.

Controlled synthesis of α-Fe2O3 nanocubes for gas-sensing applications: Feasibility of assessing crucian carp (Carassius auratus) freshness via trimethylamine levels

Trimethylamine (TMA) is an organic amine with strong pungent smell which is an indicator gas for evaluating fish freshness according to the international standard. In this work, as-synthesize α-Fe2O3 solid nanocubes (NCs), α-Fe2O3 nucleoshell NCs and α-Fe2O3 hollow NCs were used as sensing material to develop an outstanding TMA gas sensor. The response of the α-Fe2O3 hollow NCs sensors towards 20 ppm TMA at 230 ℃ was 6.3. Meanwhile, these sensors showed exceptional response/recovery time, low limit of detection, great selectivity, and outstanding linear relationship. Furthermore, the analysis of gases released during the decomposition of Carassius auratus (0–10 days) was conducted, which demonstrated the assessment of TMA by α-Fe2O3 hollow NCs sensor can evaluate the freshness of Carassius auratus. Such a novel sensor signifies the outstanding application potential in efficient gas-sensing properties of TMA, which will make the tremendous contribution for Carassius auratus product evaluation in the future.

Adsorption of Eosin B from Wastewater onto the Prepared Porous Anion Exchange Membrane.

This research describes the fabrication of the porous trimethylamine (TMA)-grafted anion exchange membrane (AEM) over a phase inversion process. The synthesis of the generated AEM was verified using Fourier transform infrared (FTIR) spectroscopy. The fabricated porous AEM showed 240% water uptake (WR), 1.45 mg/g ion exchange capacity (IEC), and a 9.0% linear expansion ratio (LER) at 25 °C. It exhibited a porous structure and higher thermal stability. It was utilized to remove eosin B (EB) from wastewater via the process of adsorption. The adsorption capacity of EB increased with time and the starting concentration of EB while decreasing with temperature and the AEM dosage. Adsorption isotherm investigation results showed that EB adsorption onto the porous AEM followed the Langmuir isotherm because the value of correlation coefficient (R2 = 0.992) was close to unity. Because the correlation coefficient was close to one, it was determined through adsorption kinetic experiments that the adsorption of EB on the produced porous AEM was suitable for a pseudo-second-order model. Thermodynamic study about process of EB adsorption on the porous AEM revealed that there was an exothermic (ΔH° = -16.60 kJ/mol) and spontaneous process.

Isolation of Lactic Acid Bacteria Eliminating Trimethylamine (TMA) for Application to Fishery Processing.

Fishy odor of fish flesh (meat) presents a severe problem for marine production. The main cause of fishy odor is trimethylamine (TMA), which increases during storage. It is produced from trimethylamine oxide (TMAO), an osmosis-regulating substance in fish cells that functions by a reduction reaction. Bacterial growth in fish meat increases TMA. Its odor reduces the commercial value of the meat. Technologies for its regulation and elimination are desired. This chapter presents a description of the use of lactic acid to eliminate TMA. The lactic acid is producible safely by bacteria during food processing using picric acid-toluene.A method of eliminating TMA was demonstrated using Lactobacillus plantarum H78. Furthermore, an assay method was explained for reducing TMA in fish meat by fermenting the H78 strain.

Trimethylamine Oxidation into the Proatherogenic Trimethylamine N-Oxide Is Higher in Coronary Heart Disease Men: From the CORDIOPREV Study.

Cardiovascular disease (CVD) is more prevalent in men than women, but the mechanisms responsible for this are not fully understood. We aimed to evaluate differences in trimethylamine (TMA), a microbial metabolite and its oxidized form, trimethylamine N-oxide (TMAO), which is thought to promote atherosclerosis, between men and women with coronary heart disease (CHD), using as a reference a non-CVD population. This study was carried out within the framework of the CORDIOPREV study (NCT00924937; June 19, 2009), a clinical trial which included 827 men and 175 women with CHD, with a non-CVD population of 375 individuals (270 men and 105 women) as a reference group. Plasma TMA and TMAO were measured by HPLC-MS/MS. The carotid study was ultrasonically assessed bilaterally by the quantification of intima-media thickness of both common carotid arteries (IMT-CC). We found higher TMAO levels and TMAO/TMA ratio in CHD men than CHD women (p=0.034 and p=0.026, respectively). No TMA sex differences were found in CHD patients. The TMA and TMAO levels and TMAO/TMA ratio were lower, and no differences between sexes were found in the non-CVD population. TMAO levels in CHD patients were consistent with higher IMT-CC and more carotid plaques (p=0.032 and p=0.037, respectively) and lower cholesterol efflux in CHD men than CHD women (p<0.001). Our results suggest that CHD men have augmented TMAO levels compared with CHD women, presumably as a consequence of higher rate of TMA to TMAO oxidation, which could be associated with CVD, as these sex differences are not observed in a non-CVD population.

GUT MICROBIOTA METABOLITES CONNECTIONS WITH ECHOCARDIOGRAPHY ATRIAL FIBRILLATION CHARACTERISTICS IN PATIENTS WITH CORONARY ARTERY DISEASE

The aim: To reveal the connections between gut microbiota metabolites and echocardiography (TTE) atrial fibrillation (AF) characteristics in patients with coronary artery disease (CAD). Materials and methods: 300 patients were divided into 3 groups: the first group(CAD) – 149 patients with CAD but without arrhythmias, the second group (CAD+AF) – 124 patients with CAD and AF paroxysm, and the control group – 27 patients without CAD and arrhythmias. TTE was done by ALOKA SSD-5000. The level of trimethylamine (TMA), trimethylamine-N-oxide (TMAO) of plasma, and fecal short-chain fatty acids (SCFA) levels were determined by gas chromatography with mass electron detection. Results: Isocaproic and isobutyric fecal acids appear in group II in comparison with CG. In group ІІ, patients’ rise of TMA (16.13%), TMAO (57.54%) levels, and decreased ratio (26.16%) in comparison with group I was revealed, P&lt;0.05. In group ІІ patients rise of valeric (1128.43%) and depletion of butyric (78.75%), isovaleric (43.71%), caprylic (99.21%) acids, middle chain fatty acids (95.54%), and the total amount of fecal SCFA (17.09%) in comparison with group I was found, P&lt;0.05. In group ІІ, patients’ rise in left atrium diameter (10.03%), left atrium volume (15.40%), and left atrium volume index (11.48%) in comparison with group I was revealed, P&lt;0.05. The largest amount of correlations was observed between echocardiography indexes and TMA (total number = 11), butyric acid (total number = 10) and TMAO (total number = 9). Left atrium diameter index, which commonly increased in patients with atrial fibrillation, was correlated with TMA (r=0.392), TMAO (r=0.333), butyric acid (r=-0.321), isobutyric acid (r=-0.359) and middle chain fatty acids (r=-0.362), P&lt;0.05. Conclusion: Associations between gut microbiota metabolites and TTE AF characteristics in patients with CAD were based mostly on correlations between left atrium indexes and TMA, TMAO, butyric acid, isobutyric acid, and middle chain fatty acids.

Quality Assessment of Newly Harvested Marine Fish in Retailed Market at Alexandria Province

A total of Sixty random samples of marine fish, including sardine, seabream, and seabass (20 of each), were chosen from the commercially significant species of harvested marine fish from retail markets in Alexandria province for chemical and microbiological assessment. The study revealed that the average values of histamine, Trimethylamine (TMA), and total volatile nitrogen (TVN) in the analyzed samples of sardine, seabream, and seabass were as follows: for sardine, the values were (0.41±0.002, 0.44±0.02, and 0.19±0.01mg/100g); for seabream, the values were (8.53±0.033, 18.03±0.27, and 12.92±0.45 mg/100g); and for seabass, the values were (18.52±0.62, 19.61±0.29, and 17.64±0.13 mg/100g). The average total bacterial count in the analyzed samples of sardine, seabream, and seabass were 17.8×105±2.6×105, 3.2×105±0.61×105, and 1.95×105±0.49×105 Cfu/g, respectively. The Enterobacteriaceae count in the same examined samples were 5.8×104 ± 3.6×104, 3.1×103 ± 0.63×103, and 2.3×103 ± 0.54×103 cfu/g, respectively. Additionally, the mean values of coliforms were 2.2×103 ± 0.51×103, 8.1×102 ± 1.02×102, and 7.4×102 ± 0.8×102 Cfu/g, respectively. E.coli and salmonella were detected in 20 and 10% of examined sardine sample, and both organisms failed to be detected in seabream and seabass, respectively, While Vibrio parahaemolyticus were detected in only one sample of examined sardine, seabream, and seabass with an incidence level (5% of each type). In conclusion, Sardine had the highest level of contamination with pathogenic organisms such as E.coli, V. parahaemolyticus and salmonella, therefore, conduct regular audits and inspections of fish processing facilities, fishing vessels, and storage areas to ensure compliance with hygiene and safety standards.

Alkaline Hydrolysis of Poultry Carcasses and Health Risk Assessment of Exposure to Target Volatile Organic Compounds

HighlightsHydroxide solutions (1 M, 2 M, 4 M) were used for chicken carcass hydrolysis.pH of hydrolysates remained above 13.1 for the entire 10 weeks.Headspace samples had characteristic fish odor due to trimethylamine.Over 17% of the workers exposed to gases for 3 hours daily risk developing serious health risks.Abstract. Animal carcass management is an essential part of a livestock production system. Alkaline hydrolysis is a relatively new disposal method used to digest and break down animal tissues. Despite the effectiveness of inactivating pathogens, alkaline hydrolysis has not been widely accepted as a disposal method because of its high capital and operating costs when done at high temperatures and pressure. The objectives of this research were (1) to test if alkaline solutions at ambient temperature and pressure can be used to hydrolyze poultry carcasses; (2) to quantify target VOCs emitted from carcasses, and (3) to neutralize and aerobically treat hydrolysates to prepare liquid fertilizer. 1 molar (M), 2 M, and 4 M potassium hydroxide solutions were used to hydrolyze chicken carcasses, and the headspace was sampled to quantify target VOCs. The pH of the hydrolysates stayed above 13.1 during the study, which was considered sufficient for eliminating pathogens of concern. Concentrations of target VOCs fluctuated over 10 weeks, and concentrations of trimethylamine (TMA), acetic acid, and propionic acid exceeded their recommended inhalation exposure limits. It was found that more than 17% of the workers exposed to the process headspace gases for 3 h a day would be at a high risk of developing serious chronic health problems. Although the results of this study indicated that chicken carcasses can be hydrolyzed under ambient conditions, they raised concerns about the health risks associated with inhalation exposure to the gases produced during the process. Future studies are needed to adjust daily exposure times depending on the ventilation rates of full-scale alkaline hydrolysis sites. Keywords: Alkaline hydrolysis, Cancer risk, Carcass, Livestock, Solid-phase microextraction.

Unravelling the Psychological Impact of Trimethylaminuria: Insights into the Management Strategies

Trimethylaminuria (TMAU), colloquially known as fish odour syndrome, is a rare metabolic disorder characterised by the body’s inability to properly metabolise Trimethylamine (TMA), resulting in a distinctive and unpleasant fishy odour in bodily secretions. This comprehensive review explores the pathophysiology, clinical manifestations, genetic basis, diagnostic challenges, and psychological impact of TMAU, along with management strategies. Genetic mutations affecting the flavin-containing monooxygenase 3 (FMO3) enzyme, which is responsible for TMA metabolism, contribute to the condition’s hereditary nature. Diagnosis can be challenging due to intermittent symptoms and overlaps with other conditions, such as Olfactory Reference Syndrome (ORS). The psychosocial impact of TMAU can be profound, leading to embarrassment, social isolation, and mental health issues. Management strategies include dietary modifications, supplements, antibiotics, and hygiene measures to alleviate symptoms. Despite advances in understanding TMAU, further research is needed to enhance diagnostic accuracy and therapeutic approaches, ultimately improving the quality of life for affected individuals.

A Chromo-fluorogenic Probe for Selective Detection of Picric Acid Alongside Its Recovery by Aliphatic Amines and Construction of Molecular Logic Gates.

Nitroaromatic compounds are illicit explosive chemicals. For environmental security and homeland safety, selective and sensitive identification of these secondary-class explosives has been a reason for the exhaustive research arena of chemists for about a decade. We introduced a sensitive optical sensor with desalted neutral red (NR) dye. After ingressing picric acid (PA) in acetonitrile, the probe becomes non-fluorescent, displaying a colorimetric changefrom yellow to pink. The quenched phenomena and the changed color were re-established with aliphatic amine, trimethylamine (TEA). The reversibility is produced cyclically, both in fluorimetrically and spectrophotometrically. The detection limit for PA with our probe comes out as 0.639µM; this value is significantly lower than many chemosensors available in the literature. Also, NR-stained filter paper strips-based test kit analysis has been deployed as a displayable photonic device for in-situ detection of PA. Furthermore, the whole system was conceptualized to produce single input, single output, and double input single output logic gates, which can be applied to digital devices. The chronological input manner as NTP (NR- TEA-PA) pushed us to configure a molecular keypad lock system, the basis of digital locking devices. The repeatable & reversible detection system exhibits "Write read- Erase-read Write-read' type memory devices.

Exposure Patterns of Multiple Pesticides and Urinary Alterations of Trimethylamine (TMA) and Trimethylamine N-Oxide (TMAO) among Pregnant Women.

Environmental exposure to pesticides is widespread and commonly occurs in mixtures, and pregnant women are particularly concerned. Trimethylamine N-oxide (TMAO), a dietary-derived catabolite linked to cardiometabolic disease, may be influenced by pesticide exposure. However, limited knowledge exists regarding the associations, and studies have primarily been restricted to single pesticides. To address this gap, we examined the associations of pesticide exposure with urinary TMA, TMAO, and TMAO-to-TMA ratio among 1067 pregnant women residing in a rural area. Latent class analysis (LCA) was applied to identify distinct patterns of pesticide exposure based on urinary metabolite concentrations. Multiple linear regression (MLR) models and Bayesian kernel machine regression (BKMR) models were employed to estimate the effects of single pesticides, exposure patterns, and combined exposure. Four distinct pesticide exposure patterns were identified. Higher concentrations of pesticide metabolites were found to be associated with increased urinary TMAO levels (β: 0.043 to 0.254, p < 0.05). In the MLR models for individual pesticides and exposure patterns, carbofuran phenol (CFP), pentachlorophenol (PCP), and 2-phenylphenol (OPP) exhibited positive associations with urinary TMA concentrations, while pyrethroid pesticide metabolites were correlated with the up-regulation of the TMAO-to-TMA ratio. Significant positive associations of pesticide mixtures with TMA, TMAO, and TMAO-to-TMA ratio were observed in the BKMR model, primarily driven by PCP and trans-DCCA. Our findings provided a perspective to reveal that the mechanisms and contributions to TMAO alterations may vary among different pesticides in mixture exposure.

Covalent Crosslinking of High-Density Polyethylene Trimethylammonium-Based Radiation-Grafted Anion Exchange Membranes for Reduced Water Uptakes and Swelling

Anion exchange membranes (AEMs) are polymer membranes of varying thickness (10 - 50 µm) with covalently bound quaternary ammonium cations, which have been evaluated in fuel cells (AEMFCs) and green hydrogen electrolysis.1,2 Radiation-grafted AEMs made from high-density polyethylene (RG-HDPE) with ca. 30 microns hydrated thickness exhibit high hydroxide conductivities, promising mechanical stabilities, and high AEMFC performances.1,3 The enhanced water transport properties is hypothesized to be from nano and microscale level structural and morphological changes.3 Our best performing ultrathin RG-HDPE films exhibited excellent conductivity and AEMFC performance retention over the 400 h.3 However, the water uptake of RG-HDPE film is ca. 150%, hence, it is important to add a controlled amount of crosslinking.4-7 In previous studies of radiation-grafted membranes for use in reverse electrodialysis, crosslinking + amination was achieved by using a heated amination fabrication step involving a mixture of liquid, high boiling point mono-amines (such as N-methylpiperidine) and a crosslinking diamine (such as N,N,N',N'-tetramethyl-1,6-hexane diamine - TMHDA).8 However, a thermal method is not viable or safe when using the commonly supplied aqueous solutions of dissolved trimethylamine (TMA) gas. This presentation will discuss a variety of approaches, to target controlled TMHDA-crosslinking of TMA-based RG-AEMs, targeting reduced water uptakes and swelling with retention of ion conductivity (Figure 1). The most promising approach involved two steps with the initial amination of the poly(VBC)-grafted HDPE intermediate membranes using a sub-stoichiometric amount of TMHDA. Square wave voltammetry analysis of the solution recovered from amination step 1 confirmed complete reaction of the added TMHDA. In the second step, the membranes were then quickly [important] reacted with aqueous TMA to complete the amination process. TMA can displace TMHDA-based head-groups after long step 2 amination times, hence, we emphasize the use of short TMA amination times in the second step.