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Emerging evidence suggests that gut bacteria‐derived trimethylamine N‐oxide (TMAO) elevates the risk of cardiovascular disease, and dietary fiber holds the potential to attenuate TMAO formation. However, the effectiveness of dietary fiber, such as inulin, in inhibiting TMAO formation remains controversial. Therefore, this study investigated the effect of inulin supplementation on TMAO formation in mice with high TMAO levels induced by a high‐fat diet (HFD) combined with choline and L‐carnitine. Results showed that HFD treatment significantly elevated blood TMAO concentrations and increased the abundances of TMAO formation‐associated gut bacteria, as well as the abundances of functional genes responsible for TMA formation. While the supplementation of choline and L‐carnitine greatly enhanced blood trimethylamine (TMA) and TMAO levels, inulin supplementation did not significantly affect TMAO levels and had limited impact on TMA‐associated gut bacteria, except for Desulfitobacterium hafniense. [ABSTRACT FROM AUTHOR]

Trimethylamine N‐oxide (TMAO) is a circulating microbiome‐derived metabolite implicated in the development of atherosclerosis and cardiovascular disease (CVD). We investigated whether plasma levels of TMAO, its precursors (betaine, carnitine, deoxycarnitine, choline), and TMAO‐to‐precursor ratios are associated with clinical outcomes, including CVD and mortality. This was followed by an in‐depth analysis of their genetic, gut microbial, and dietary determinants. The analyses were conducted in five Dutch prospective cohort studies including 7834 individuals. To further investigate association results, Mendelian Randomization (MR) was also explored. We found only plasma choline levels (hazard ratio [HR] 1.17, [95% CI 1.07; 1.28]) and not TMAO to be associated with CVD risk. Our association analyses uncovered 10 genome‐wide significant loci, including novel genomic regions for betaine (6p21.1, 6q25.3), choline (2q34, 5q31.1), and deoxycarnitine (10q21.2, 11p14.2) comprising several metabolic gene associations, for example, CPS1 or PEMT. Furthermore, our analyses uncovered 68 gut microbiota associations, mainly related to TMAO‐to‐precursors ratios and the Ruminococcaceae family, and 16 associations of food groups and metabolites including fish‐TMAO, meat‐carnitine, and plant‐based food‐betaine associations. No significant association was identified by the MR approach. Our analyses provide novel insights into the TMAO pathway, its determinants, and pathophysiological impact on the general population. Highlights: Exploration of microbiome‐related metabolites (trimethylamine N‐oxide [TMAO], choline, betaine, l‐carnitine, and deoxycarnitine) in 7834 participants from five population cohorts.Cardiovascular risk was associated with elevated choline concentrations, but not with TMAO concentrations.Characterization of the genetic architecture behind metabolite concentration variability.Identification of gut microbial taxonomic abundance associated with metabolite's plasma concentration levels.Fish intake is the major dietary driver of TMAO concentrations, and betaine is related to grains and vegetable intake. [ABSTRACT FROM AUTHOR]

Background and Aims: Emerging evidence suggests a detrimental impact of high red meat intake on hepatic steatosis. We investigated the potential interplay between red meat intake and gut microbiome on circulating levels of trimethylamine N‐oxide (TMAO) and hepatic steatosis risk. Methods: This cross‐sectional study was conducted in a representative sample of 754 community‐dwelling adults in Huoshan, China. Diet was collected using 4 quarterly 3 consecutive 24‐h dietary (12‐day) recalls. We profiled faecal microbiome using 16S ribosomal RNA sequencing and quantified serum TMAO and its precursors using LC‐tandem MS (n = 333). We detected hepatic steatosis by FibroScan. The adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated using logistic regression. Results: TMAO levels but not its precursors were positively associated with the likelihood of hepatic steatosis (aOR per 1‐SD increment 1.86, 95% CI 1.04–3.32). We identified 14 bacterial genera whose abundance was associated with TMAO concentration (pFDR <.05) belonging to the phyla Firmicutes, Bacteroidetes, Actinobacteria and Proteobacteria families. Per 10 g/day increase in red meat intake was positively associated with TMAO levels among participants who had higher red meat intake (>70 g/day) and higher TMAO‐predicting microbial scores (TMS, β =.045, p =.034), but not among others (pinteraction =.030). TMS significantly modified the positive association between red meat and steatosis (pinteraction =.032), with a stronger association being observed among participants with higher TMS (aOR 1.30, 95% CI 1.07–1.57). Conclusions: The bacterial genera that predicted TMAO levels may jointly modify the association between red meat intake and TMAO levels and the subsequent risk of hepatic steatosis. [ABSTRACT FROM AUTHOR]

Gut microbes play a pivotal role in host physiology by producing beneficial or detrimental metabolites. Gut bacteria metabolize dietary choline and L‐carnitine to trimethylamine (TMA) which is then converted to trimethylamine‐N‐oxide (TMAO). An elevated circulating TMAO is associated with diabetes, obesity, cardiovascular disease, and cancer in humans. In the present study, we investigated the effect of dietary blueberries and strawberries at a nutritional dosage on TMA/TMAO production and the possible role of gut microbes. Blueberry cohort mice received a control (C) or freeze‐dried blueberry supplemented (CB) diet for 12 weeks and subgroups received an antibiotics cocktail (CA and CBA). Strawberry cohort mice received a control (N) or strawberry‐supplemented (NS) diet and subgroups received antibiotics (NA and NSA). Metabolic parameters, choline, TMA, and TMAO were assessed in addition to microbial profiling and characterization of berry powders. Blueberry supplementation (equivalent to 1.5 human servings) reduced circulating TMAO in CB versus C mice (~48%) without changing choline or TMA. This effect was not mediated through alterations in metabolic parameters. Dietary strawberries did not reduce choline, TMA, or TMAO. Depleting gut microbes with antibiotics in these cohorts drastically reduced TMA and TMAO to not‐quantified levels. Further, dietary blueberries increased the abundance of bacterial taxa that are negatively associated with circulating TMA/TMAO suggesting the role of gut microbes. Our phenolic profiling indicates that this effect could be due to chlorogenic acid and increased phenolic contents in blueberries. Our study provides evidence for considering dietary blueberries to reduce TMAO and prevent TMAO‐induced complications. [ABSTRACT FROM AUTHOR]

Overall diet, lifestyle choices, genetic predisposition, and other underlying health conditions may contribute to higher trimethylamine N‐oxide (TMAO) levels and increased cardiovascular risk. This review explores the potential therapeutic ability of RSV to protect against cardiovascular diseases (CVD) and affect TMAO levels. This review considers recent studies on the association of TMAO with CVD. It also examines the sources, mechanisms, and metabolism of TMAO along with TMAO‐induced cardiovascular events. Plant polyphenolic compounds, including resveratrol (RSV), and their cardioprotective mechanism of regulating TMAO levels and modifying gut microbiota are also discussed here. RSV's salient features and bioactive properties in reducing CVD have been evaluated. The close relationship between TMAO and CVD is clearly understood from currently available data, making it a potent biomarker for CVD. Precise investigation, including clinical trials, must be performed to understand RSV's mechanism, dose, effects, and derivatives as a cardioprotectant agent. [ABSTRACT FROM AUTHOR]

The phase distribution and organic spacer cations play pivotal roles in determining the emission performance and stability of perovskite quantum wells (QWs). Here, we propose a universal molecular regulation strategy to tailor phase distribution and enhance the stability of CsPbBr3 QWs. The capability of sterically hindered ligands with formidable surface binding groups is underscored in directing CsPbBr3 growth and refining phase distribution. With trimethylamine modified boron dipyrromethene (BDP‐TMA) ligand as a representative, the BDP‐TMA driven can precisely control phase distribution and passivate defects of CsPbBr3. Notably, BDP‐TMA acts as a co‐spacer organic entity in obtained BDP‐TMA‐CsPbBr3, facilitating efficient singlet energy transfer and tailoring the luminescence to produce a distinctive bluish‐white emission. The BDP‐TMA‐CsPbBr3 demonstrates significant phase stability under water exposure, light irradiation, and moderate temperature. Interestingly, BDP‐TMA‐CsPbBr3 exhibits the thermally‐induced dynamic fluorescence control at elevated temperatures, which can be achieved feasible for advanced information encryption. This discovery paves the way for the exploration of perovskite QWs in applications like temperature sensing, anti‐counterfeiting, and other advanced optical smart technologies. [ABSTRACT FROM AUTHOR]

Background: Chronic kidney disease (CKD) patients exhibit a heightened cardiovascular (CV) risk which may be partially explained by increased medial vascular calcification. Although gut‐derived uremic toxin trimethylamine N‐oxide (TMAO) is associated with calcium‐phosphate deposition, studies investigating phenylacetylglutamine's (PAG) pro‐calcifying potential are missing. Methods: The effect of TMAO and PAG in vascular calcification was investigated using 120 kidney failure patients undergoing living‐donor kidney transplantation (LD‐KTx), in an observational, cross‐sectional manner. Uremic toxin concentrations were related to coronary artery calcification (CAC) score, epigastric artery calcification score, and markers of established non‐traditional risk factors that constitute to the 'perfect storm' that drives early vascular aging in this patient population. Vascular smooth muscle cells were incubated with TMAO or PAG to determine their calcifying effects in vitro and analyse associated pathways by which these toxins may promote vascular calcification. Results: TMAO, but not PAG, was independently associated with CAC score after adjustment for CKD‐related risk factors in kidney failure patients. Neither toxin was associated with epigastric artery calcification score; however, PAG was independently, positively associated with 8‐hydroxydeoxyguanosine. Similarly, TMAO, but not PAG, promoted calcium‐phosphate deposition in vitro, while both uremic solutes induced oxidative stress. Conclusions: In conclusion, our translational data confirm TMAO's pro‐calcifying effects, but both toxins induced free radical production detrimental to vascular maintenance. Our findings suggest these gut‐derived uremic toxins have different actions on the vessel wall and therapeutically targeting TMAO may help reduce CV‐related mortality in CKD. [ABSTRACT FROM AUTHOR]

Background and purpose: It has been suggested that trimethylamine N‐oxide (TMAO) is related to Parkinson's disease (PD) in observational studies. However, the direction of this association is inconsistent. An exploratory Mendelian randomization study was conducted to investigate whether TMAO and its precursors have a causal relationship with PD. Methods: Summary statistics were obtained for single nucleotide polymorphisms related to circulating levels of TMAO, betaine, carnitine and choline, and the corresponding data for the risk, age at onset and progression of PD from genome‐wide association studies. Inverse‐variance weighting was used as the primary method for effect estimation. The false discovery rate was applied to the correction of multiple testing. A p value of association <0.05 but above the false discovery rate corrected threshold was deemed suggestive evidence of a possible association. A range of robust Mendelian randomization methods were used for sensitivity analysis. Results: Suggestive evidence was observed of an inverse causal effect of TMAO on motor fluctuations (odds ratio [OR] 0.851, 95% confidence interval [CI] 0.731, 0.990, p = 0.037) and carnitine on insomnia (OR 0.817, 95% CI 0.700, 0.954, p = 0.010) and a positive causal effect of betaine on Hoehn–Yahr stage (OR 1.397, 95% CI 1.112, 1.756, p = 0.004), Unified Parkinson's Disease Rating Scale (UPDRS) III score (β = 0.138, 95% CI 0.051, 0.225, p = 0.002), motor fluctuations (OR 1.236, 95% CI 1.011, 1.511, p = 0.039), and choline on UPDRS IV (β = 0.106, 95% CI 0.026, 0.185, p = 0.009) and modified Schwab and England Activities of Daily Living Scale score (β = 0.806, 95% CI 0.127, 1.484, p = 0.020). Conclusions: Our findings provide suggestive evidence that TMAO and its precursors have a causal effect on the progression of PD. Further investigation of the underlying mechanisms is required. [ABSTRACT FROM AUTHOR]

BACKGROUND: Rahnella aquatilis is a recognised microbial threat that alters the sensory properties of seafood. The high frequency with which R. aquatilis is isolated from fish has prompted a search for alternative preservatives. In the present study, in vitro and fish‐based ecosystem (raw salmon‐based medium) approaches were used to validate the antimicrobial effects of gallic (GA) and ferulic (FA) acids against R. aquatilis KM05. The results were compared with data describing the response of KM05 to sodium benzoate. Bioinformatics data of the whole genome were used to analyse the potential for fish spoilage by KM05 in detail, and the results revealed the main physiological characteristics that underlie reduced seafood quality. RESULTS: In the KM05 genome, the most abundantly enriched Gene Ontology terms were 'metabolic process', 'organic substance metabolic process' and 'cellular process'. Through an evaluation of the Pfam annotations, 15 annotations were found to be directly involved in the proteolytic activity of KM05. Peptidase_M20 was the most abundantly represented (abundance value of 14060). Proteins representing the CutC family (abundance value of 427) indicated the potential for KM05 degradation of trimethyl‐amine‐N‐oxide. Subinhibitory concentrations of GA and FA suppressed the proteolytic activities of KM05 both in vitro and in RS medium by an average of 33–45%. These results were confirmed by quantitative real‐time PCR experiments, which also showed that the expression levels of genes involved in proteolytic activities and volatile trimethylamine production were also decreased. CONCLUSION: Phenolic compounds can be used as potential food additives for preventing quality deterioration of fish products. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In the literature, there have been several studies available investigating the relationship between autism spectrum disorder and intestinal permeability. In this study, it is aimed to examine the relationship between the levels of trimethylamine N‐oxide (TMAO), which is a parameter associated with intestinal permeability, and lipopolysaccharide binding protein (LBP), which is a marker associated with bacterial translocation from the intestine, in patients with autism spectrum disorder (ASD) and healthy controls. Fifty‐three children with ASD as the patient group and 30 healthy children as the control group have been included in the study. The diagnostic evaluation has been made according to DSM‐5 criteria. According to the obtained results, there has been no significant difference between groups in terms of serum TMAO and LBP levels. Considering the existence of various studies that found different results on ASD and intestinal permeability, it is thought that the studies conducted in this field that did not find statistically different results will also make a contribution to the literature. [ABSTRACT FROM AUTHOR]

We aimed to evaluate whether improving maternal diet during lactation in diet‐induced obese rats reverts the impact of western diet (WD) consumption on the metabolome of milk and offspring plasma, as well as to identify potential biomarkers of these conditions. Three groups of dams were followed: control‐dams (CON‐dams), fed with standard diet (SD); WD‐dams, fed with WD prior and during gestation and lactation; and reversion‐dams (REV‐dams), fed as WD‐dams but moved to SD during lactation. Metabolomic analysis was performed in milk at lactation days 5, 10, and 15, and in plasma from their male and female offspring at postnatal day 15. Milk of WD‐dams presented, throughout lactation and compared to CON‐dams, altered profiles of amino acids and of the carnitine pool, accompanied by changes in other polar metabolites, being stachydrine, N‐acetylornithine, and trimethylamine N‐oxide the most relevant and discriminatory metabolites between groups. The plasma metabolome profile was also altered in the offspring of WD‐dams in a sex‐dependent manner, and stachydrine, ergothioneine and the acylcarnitine C12:1 appeared as the top three most discriminating metabolites in both sexes. Metabolomic changes were largely normalized to control levels both in the milk of REV‐dams and in the plasma of their offspring. We have identified a set of polar metabolites in maternal milk and in the plasma of the offspring whose alterations may indicate maternal intake of an unbalanced diet during gestation and lactation. Levels of these metabolites may also reflect the beneficial effects of implementing a healthier diet during lactation. [ABSTRACT FROM AUTHOR]

N,N'‐Diaryl ethylenediamines are common feedstocks in organic synthesis and important structural motifs in medicinal chemistry. Whereas the C−N formation reactions based on anilines and aryl halides are the most direct methods to access N,N'‐diaryl ethylenediamines, the photocatalytic synthetic version remains undeveloped. Herein we describe the dual nickel/photoredox‐catalyzed amination reaction using nitroarenes and trimethylamine as reaction substrates. This cascade transformation hinges on the multiple C−N and C−C coupling events based on the nitrogen radical and α‐aminomethyl radical derived from nitroarene and trimethylamine, respectively. A variety of N‐formyl N,N'‐diaryl ethylenediamines can be obtained under the reaction protocol. Subsequent hydrolysis offers the N,N'‐diaryl ethylenediamines for further derivatizations. [ABSTRACT FROM AUTHOR]

Background: The aim of this study is to investigate the effect of trimethylamine (TMA) and trimethylamine‐n‐oxide (TMAO) on the contractility of human umbilical artery and the possible mechanisms involved. Methods: Vasoactive responses to TMA and TMAO on human umbilical artery rings were measured in isolated organ baths. Cumulative dose–response curves for TMA and TMAO were obtained before and after incubation with atropine, yohimbine, prazosin, indomethacin, verapamil, and Ca+2‐free Krebs–Henselite solution. Results: Administration of cumulative TMA and TMAO resulted in dose‐dependent contraction at concentrations ranging from 10 to 100 mM on human umbilical artery rings. TMA‐induced contractions were more potent than TMAO‐induced contractions (TMA: −logEC50 = 1.00 ± 0.02, TMAO: −logEC50 = 0.57 ± 0.02). Contraction responses to TMA were significantly lower in the presence of verapamil and in the absence of external Ca+2 (p < 0.001, p < 0.05, respectively). Conclusion: Our results showed that TMA and TMAO caused vasoconstriction in isolated human umbilical artery rings. Our findings also indicated that TMA but not TMAO‐induced vasoconstriction was partially dependent on extracellular Ca2+ and calcium influx through L‐type Ca2+ channels. Our results suggest that TMA and TMAO may have the potential to contribute to cardiovascular diseases through their direct effect on vascular contractility in human arteries. [ABSTRACT FROM AUTHOR]

A metal‐free and oxidant‐free electrochemically enabled strategy for C‐3 formylation of imidazopyridines using trimethylamine as a one‐carbon source has been established. This conversion has high functional group compatibility under mild conditions and ensures late‐stage functionalization of pharmaceutical molecules. Furthermore, unexpected hexafluoroisopropoxylation products have been observed in some cases. Mechanistic studies using cyclic voltammetry and control experiments reveal the key intermediate of the formylation process. [ABSTRACT FROM AUTHOR]

Background and Aims: The gut microbiome‐related metabolites betaine and trimethylamine N‐oxide (TMAO) affect major health issues. In cirrhosis, betaine metabolism may be diminished because of impaired hepatic betaine homocysteine methyltransferase activity, whereas TMAO generation from trimethylamine may be altered because of impaired hepatic flavin monooxygenase expression. Here, we determined plasma betaine and TMAO levels in patients with end‐stage liver disease and assessed their relationships with liver disease severity. Methods: Plasma betaine and TMAO concentrations were measured by nuclear magnetic resonance spectroscopy in 129 cirrhotic patients (TransplantLines cohort study; NCT03272841) and compared with levels from 4837 participants of the PREVEND cohort study. Disease severity was assessed by Child‐Pugh‐Turcotte (CPT) classification and Model for End‐stage Liver Disease (MELD) score. Results: Plasma betaine was on average 60% higher (p <.001), whereas TMAO was not significantly lower in cirrhotic patients vs. PREVEND population (p =.44). After liver transplantation (n = 13), betaine decreased (p =.017; p =.36 vs. PREVEND population), whereas TMAO levels tended to increase (p =.085) to higher levels than in the PREVEND population (p =.003). Betaine levels were positively associated with the CPT stage and MELD score (both p <.001). The association with the MELD score remained in the fully adjusted analysis (p <.001). The association of TMAO with the MELD score did not reach significance (p =.11). Neither betaine nor TMAO levels were associated with mortality on the waiting list for liver transplantation (adjusted p =.78 and p =.44, respectively). Conclusion: Plasma betaine levels are elevated in cirrhotic patients in parallel with disease severity and decrease after liver transplantation. [ABSTRACT FROM AUTHOR]

The heart and gut relationship: a systematic review of the evaluation of the microbiome and trimethylamine-N-oxide (TMAO) in heart failure. FMO3-TMAO axis modulates the clinical outcome in chronic heart-failure patients with reduced ejection fraction: evidence from an Asian population. Heart failure and trimethylamine N-oxide: time to transform a "gut feeling" in a fact?. [Extracted from the article]

Coronary heart disease (CHD) is defined by atherosclerosis, which may result in stenosis or blockage of the arterial cavity, leading to ischemic cardiac diseases such as angina and myocardial infarction (MI). Accumulating evidence indicates that the gut microbiota play a critical role in the initiation and progression of CHD. The gut microbial metabolite trimethylamine N‐oxide (TMAO) is intimately linked to the pathophysiology of CHD. The hepatic flavin‐containing monooxygenases (FMOs) convert trimethylamine (TMA) to TMAO. As a result, it is critical to prevent TMA generation. Stilbenes could reduce cardiovascular disease mortality. Twelve stilbenes with inhibitory activity against TMA‐lyase were compiled and evaluated in this study. Docking results showed Resveratroloside had the highest Vina score, indicating that it was the most active and might be employed as a lead molecule for further structural modification. [ABSTRACT FROM AUTHOR]

Background: Trimethylamine N‐oxide (TMAO) is an amine oxide generated by gut microbial metabolism. TMAO may contribute to atherothrombosis and systemic inflammation. However, the prognostic value of circulating TMAO for risk stratification is uncertain. Methods: We assessed prospective relationships of plasma TMAO with long‐term risk of all‐cause, cardiovascular (CV), and non‐CV mortality in the Western Norway Coronary Angiography Cohort (WECAC; 4132 patients with suspected coronary artery disease) and the Hordaland Health Study (HUSK; 6393 community‐based subjects). Risk associations were examined using Cox regression analyses. Results: Mean follow‐up was 9.8 and 10.5 years in WECAC and HUSK, respectively. Following adjustments for established CV risk factors and indices of renal function in WECAC, the hazard ratios (HRs) (95% confidence intervals [CIs]) per one standard deviation increase in log‐transformed plasma TMAO were 1.04 (0.97–1.12), 1.06 (0.95–1.18), and 1.03 (0.93–1.13) for all‐cause, CV, and non‐CV mortality, respectively. Essentially similar results were obtained in patients with angiographically significant coronary artery disease and patients with reduced left ventricular ejection fraction. Corresponding HRs (95% CIs) in the HUSK cohort were 1.03 (0.96–1.10), 1.01 (0.89–1.13), and 1.03 (0.95–1.12) for all‐cause‐, CV, and non‐CV mortality, respectively. Conclusions: Circulating TMAO did not predict long‐term all‐cause, CV, or non‐CV mortality in patients with coronary heart disease or in community‐based adults. This large study does not support a role of TMAO for patient risk stratification in primary or secondary prevention. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to investigate the association between trimethylamine N‐oxide (TMAO) and the prognosis and association between high‐sensitivity C‐reactive protein (hsCRP) and TMAO‐associated cardiovascular risk in patients with acute myocardial infarction (AMI) complicated by heart failure (HF). Methods and results: A total of 985 patients presenting with AMI and HF were consecutively enrolled at the Fuwai Hospital between March 2017 and January 2020. Patients were stratified into groups according to tertiles of TMAO levels and the median hsCRP levels. The primary endpoint was major adverse cardiac events (MACE), including all‐cause death, recurrence of myocardial infarction, and rehospitalization due to HF. During a median follow‐up of 716 days, 138 (14.0%) patients experienced MACE. Cox regression analyses showed that the adjusted hazard ratio (HR) for MACE was higher in patients in tertile 3 [TMAO > 9.52 μmol/L, HR: 1.85, 95% confidence interval (CI): 1.18–2.89; P = 0.007] than in tertile 1 (TMAO < 4.74 μmol/L), whereas no significant differences were detected between the patients in tertiles 1 and 2 (TMAO = 4.74–9.52 μmol/L, HR: 0.96, 95% CI: 0.59–1.58; P = 0.874). Restricted cubic spline regression depicted an S‐shaped association between TMAO and MACE (P for nonlinearity = 0.012). In the setting of hsCRP above the median level (6.68 mg/L), per unit increase of TMAO was associated with a 20% increase of MACE risk (HR: 1.20, 95% CI: 1.05–1.37, P = 0.009); increasing tertiles of TMAO were significantly associated with a higher risk of MACE (adjusted P = 0.007 for interaction; P < 0.001 for trend across tertiles). The Kaplan–Meier analysis indicated that patients in tertile 3 had a significantly lower event‐free survival (P = 0.001) when the hsCRP level was above the median level. No similar association between TMAO and MACE was observed when the hsCRP level was below the median level. Conclusions: High plasma TMAO levels were independently correlated with poor prognosis in patients with AMI complicated by HF, especially in those with higher hsCRP levels. There was an S‐shaped relationship between TMAO and HR for MACE. [ABSTRACT FROM AUTHOR]

Artificial senses like electronic nose, which ameliorates the problem of poor selectivity from single gas sensor, have elicited keen research interest to monitor hazardous gases. Herein, the doping effects of gallium on In2O3 nanotubes (NTs) are investigated and a four‐component sensor array for the detection of trimethylamine (TMA) is reported. All‐gallium‐doped/alloyed In2O3 (Ga‐In2O3) sensors show improved sensitivity and selectivity to TMA at an operating temperature of 240 °C, with 5 mol% Ga‐doped/alloyed one displaying the highest response in the range of 0.5–100 ppm and the lowest detection limit of 13.83 ppb. Based on the gas‐sensing properties, a four‐component sensor array is fabricated, which shows unique response patterns in variable‐gas backgrounds. Herein, back propagation neural network (BPNN), radial basis function neural network (RBFNN), and principal component analysis‐based linear regression (PCA‐LR) are trained with the gas‐sensing data to discriminate different gases with high accuracy, as well as to predict the concentrations of target gases in different gases and gas mixtures. Furthermore, accuracies of 92.85% and 99.14% can be achieved for the classification of six gases (three single gases and three binary gas mixtures) and for the prediction of TMA concentrations in the presence of different concentrations of TMA and acetone, respectively. [ABSTRACT FROM AUTHOR]

A metal‐free hydrogenation of quinoxalines and indoles with Me3N ⋅ BH3 and TFA in water at room temperature is reported. The protocol is featured with the usage of environmentally friendly water as the solvent, no need of metal catalyst and broad substrate scope. Sensitive functional groups such as OH‐, NH2‐, Cl‐, Br‐, especially ‐CN and ‐CO2Me were well tolerated. Preliminary mechanistic studies suggested that TFA and Me3N ⋅ BH3 provided the proton and hydride sources for the product, respectively. [ABSTRACT FROM AUTHOR]

Trimethylamine N‐oxide (TMAO) is produced in the gut via metabolism of dietary betaine, choline, and carnitine, and elevated TMAO in plasma is associated with adverse health effects, including cardiovascular events. Currently, we lack high throughput methods for sensing these metabolites and detecting high TMAO. Thus, we have adapted our previously described "imprint‐and‐report" fluorescent sensing method using dynamic combinatorial libraries (DCLs) to create a sensor array for these four metabolites that functions at physiologically relevant concentrations. Templation of DCLs with dye and subsequent addition of analytes generates a fluorescent fingerprint for each metabolite and allows for differentiation via principal component analysis (PCA). Furthermore, we demonstrate that this system can be used to characterize mixtures of the metabolites in both buffer and human plasma samples. Using three to six DCLs, we can distinguish between plasma samples with healthy and elevated levels of TMAO. [ABSTRACT FROM AUTHOR]

A new kind of small organic NIR‐II fluorophore molecule (ZS‐1010) based on intermolecular charge transfer was developed as a NIR‐II fluorescent probe for trimethylamine (TMA) detection, which is important for the diagnosis of cardiovascular disease, chronic kidney disease and diabetes. ZS‐1010 has a strong push–pull electron system composed of electron donor unit and electron acceptor unit, exhibiting strong absorption and emission in the NIR‐II region. When mixed with TMA which possesses strong electron‐donating characteristics, the push–pull system of ZS‐1010 will be affected along with the dipole moment change, leading to the quenching of fluorescence. This is the first example of TMA fluorescent probe in the NIR‐II window showing deep penetration, fast response speed, high selectivity and pH stability. [ABSTRACT FROM AUTHOR]

Intermolecular hydroaminoalkylation reactions of symmetrical and unsymmetrical alkynes with tertiary amines take place in the presence of catalytic amounts of TiBn4, Ph3C[B(C6F5)4], and a sterically demanding aminopyridinato ligand precursor. The resulting products, synthetically and pharmaceutically useful tertiary β,γ‐disubstituted allylic amines, are formed in convincing yields and with excellent stereoselectivity. Particularly promising for future applications is the fact that even the industrial side product trimethylamine can be used as a substrate. [ABSTRACT FROM AUTHOR]

The recently isolated methanogen Methanonatronarchaeum thermophilum is an extremely haloalkaliphilic and moderately thermophilic archaeon and belongs to the novel class Methanonatronarchaeia in the phylum Halobacteriota. The knowledge about the physiology and biochemistry of members of the class Methanonatronarchaeia is still limited. It is known that M. thermophilum performs hydrogen or formate‐dependent methyl‐reducing methanogenesis. Here, we show that the organism was able to grow on all tested C1‐methylated substrates (methanol, trimethylamine, dimethylamine, monomethylamine) in combination with formate or molecular hydrogen. A temporary accumulation of intermediates (dimethylamine or/and monomethylamine) in the medium occurred during the consumption of trimethylamine or dimethylamine. The energy conservation of M. thermophilum was dependent on a respiratory chain consisting of a hydrogenase (VhoGAC), a formate dehydrogenase (FdhGHI), and a heterodisulfide reductase (HdrDE) that were well adapted to the harsh physicochemical conditions in the natural habitat. The experiments revealed the presence of two variants of energy‐conserving oxidoreductase systems in the membrane. These included the H2: heterodisulfide oxidoreductase system, which has already been described in Methanosarcina species, as well as the novel formate: heterodisulfide oxidoreductase system. The latter electron transport chain, which was experimentally proven for the first time, distinguishes the organism from all other known methanogenic archaea and represents a unique feature of the class Methanonatronarchaeia. Experiments with 2‐hydroxyphenazine and the inhibitor diphenyleneiodonium chloride indicated that a methanophenazine‐like cofactor might function as an electron carrier between the hydrogenase/ formate dehydrogenase and the heterodisulfide reductase. [ABSTRACT FROM AUTHOR]

Summary: Eubacterium maltosivorans YIT is a human intestinal isolate capable of acetogenic, propionogenic and butyrogenic growth. Its 4.3‐Mb genome sequence contains coding sequences for 4227 proteins, including 41 different methyltransferases. Comparative proteomics of strain YIT showed the Wood–Ljungdahl pathway proteins to be actively produced during homoacetogenic growth on H2 and CO2 while butyrogenic growth on a mixture of lactate and acetate significantly upregulated the production of proteins encoded by the recently identified lctABCDEF cluster and accessory proteins. Growth on H2 and CO2 unexpectedly induced the production of two related trimethylamine methyltransferases. Moreover, a set of 16 different trimethylamine methyltransferases together with proteins for bacterial microcompartments were produced during growth and deamination of the quaternary amines, betaine, carnitine and choline. Growth of strain YIT on 1,2‐propanediol generated propionate with propanol and induced the formation of bacterial microcompartments that were also prominently visible in betaine‐grown cells. The present study demonstrates that E. maltosivorans is highly versatile in converting low‐energy fermentation end‐products in the human gut into butyrate and propionate whilst being capable of preventing the formation of the undesired trimethylamine by converting betaine and other quaternary amines in bacterial microcompartments into acetate and butyrate. [ABSTRACT FROM AUTHOR]

Acetaminophen (APAP)‐induced acute liver injury (AILI) is the most frequent cause of acute liver failure in developed countries. Trimethylamine N‐oxide (TMAO) is a metabolite derived from the gut microbiota and is relatively high in the circulation of the elderly, individuals with diabetes, and heart disease. Herein, we showed that TMAO exacerbates APAP hepatotoxicity. It is possible that delayed liver repair and regeneration that resulted from reduced macrophage accumulation was responsible for this combined hepatotoxicity. Moreover, matrix metalloproteinase 12 (Mmp12), expressed predominantly by macrophages, were reduced by TMAO in vitro and in vivo. This led to the inhibition of macrophage migration and a subsequent decrease in the recruitment of proresolving macrophages to the necrosis area. Furthermore, the administration of recombinant Mmp12 mitigated the enhanced hepatotoxicity in mice cotreated with TMAO and APAP. Overall, this study indicates that TMAO exacerbates APAP‐induced hepatotoxicity by hindering macrophage‐mediated liver repair, which might stem from the inhibition of Mmp12. These findings imply that liver damage in patients with high levels of circulating TMAO may be more severe in AILI and should exercise caution when treating with NAC. [ABSTRACT FROM AUTHOR]

BACKGROUND: Trimethylamine (TMA), as a harmful nitrogenous gas, is potentially toxic to animals and human beings. In recent years, the emission of TMA has caused huge environmental problems. TMA is strongly toxic and carcinogenic and requires efficient treatment technology. Photocatalysis and photoelectrocatalysis (PEC) have attracted great interest because of their environmental friendliness and high efficiency. The key problem is how to construct high‐efficiency systems and prepare high‐activity catalysts. RESULTS: To eradicate TMA in air, an efficient electrochemical system with bio‐anode and photocathode (g‐C3N4‐TiO2) was designed. It removed TMA in air continuously and efficiently, for both single‐cathode and double‐cathode systems. This is the first report about TMA removal in such integrated g‐C3N4/TiO2 photocathode and bio‐electrochemical system. Effects of reaction conditions were investigated, such as the TMA concentrations and flow rates. The highest efficiency for TMA removal was in an integrated PEC and microbial fuel cell (MFC) system with potassium persulfate (PS) activation. The double‐cathode PEC–MFC–PS system could remove more TMA (1.9 g m−3 h−1versus 1.3 g m−3 h−1) compared with the double‐cathode PEC–MFC system. CONCLUSIONS: A novel TMA treatment system – PEC–MFC system – was constructed, coupling PEC with MFC for continuous removal of TMA from air. Combined with activated PS, a PEC–MFC–PS system was designed and constructed and proved effective in oxidizing gaseous TMA and generating electricity at the same time, which has practical application prospects for the treatment of TMA pollution. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Summary: In the surface waters of the warm oligotrophic ocean, filaments and aggregated colonies of the nitrogen (N)‐fixing cyanobacterium Trichodesmium create microscale nutrient‐rich oases. These hotspots fuel primary productivity and harbour a diverse consortium of heterotrophs. Interactions with associated microbiota can affect the physiology of Trichodesmium, often in ways that have been predicted to support its growth. Recently, it was found that trimethylamine (TMA), a globally abundant organic N compound, inhibits N2 fixation in cultures of Trichodesmium without impairing growth rate, suggesting that Trichodesmium can use TMA as an alternate N source. In this study, 15N‐TMA DNA stable isotope probing (SIP) of a Trichodesmium enrichment was employed to further investigate TMA metabolism and determine whether TMA‐N is incorporated directly or secondarily via cross‐feeding facilitated by microbial associates. Herein, we identify two members of the marine Roseobacter clade (MRC) of Alphaproteobacteria as the likely metabolizers of TMA and provide genomic evidence that they converted TMA into a more readily available form of N, e.g., ammonium (NH4+), which was subsequently used by Trichodesmium and the rest of the community. The results implicate microbiome‐mediated carbon (C) and N transformations in modulating N2 fixation and thus highlight the involvement of host‐associated heterotrophs in global biogeochemical cycling. [ABSTRACT FROM AUTHOR]

Gut bacteria release trimethylamine (TMA) from dietary substrates. TMA is absorbed and is subsequently oxidized in the liver to produce trimethylamine N‐oxide (TMAO). Plasma TMAO levels are positively correlated with risk for type 2 diabetes (T2D) and cardiovascular disease (CVD). High‐fat diet (HFD) consumption has been reported to increase fasting and postprandial TMAO in sedentary individuals. However, whether the increase in TMAO with consumption of an HFD is observed in endurance‐trained males is unknown. Healthy, sedentary (n = 17), and endurance‐trained (n = 7) males consumed a 10‐day eucaloric diet comprised of 55% carbohydrate, 30% total fat, and <10% saturated fat prior to baseline testing. Blood samples were obtained in a fasted state and for a 4‐hour high‐fat challenge (HFC) meal at baseline and then again following 5‐day HFD (30% carbohydrate, 55% total fat, and 25% saturated fat). Plasma TMAO and TMA‐moiety (choline, betaine, L‐carnitine) concentrations were measured using isocratic ultraperformance liquid chromatography‐tandem mass spectrometry. Age (23 ±3 vs. 22 ± 2 years) and body mass index (23.0 ± 3.0 vs. 23.5 ± 2.1 kg/m2) were similar (both p > 0.05) in the sedentary and endurance‐trained group, respectively. VO2max was significantly higher in the endurance‐trained compared with sedentary males (56.7 ± 8.2 vs. 39.9 ± 6.0 ml/kg/min). Neither the HFC nor the HFD evoked a detectable change in plasma TMAO (p > 0.05) in either group. Future studies are needed to identify the effects of endurance training on TMAO production. [ABSTRACT FROM AUTHOR]

The use of total volatile basic nitrogen (TVB‐N) as a quality parameter for fish is rapidly growing to include other types of meat. Investigations of meat quality have recently focused on TVB‐N as an index of freshness, but little is known on the biochemical pathways involved in its generation. Furthermore, TVB‐N and methylated amines have been reported to exert deterimental health effects, but the relationship between these compounds and human health has not been critically reviewed. Here, literature on the formative pathways of TVB‐N has been reviewed in depth. The association of methylated amines and human health has been critically evaluated. Interventions to mitigate the effects of TVB‐N on human health are discussed. TVB‐N levels in meat can be influenced by the diet of an animal, which calls for careful consideration when using TVB‐N thresholds for regulatory purposes. Bacterial contamination and temperature abuse contribute to significant levels of post‐mortem TVB‐N increases. Therefore, controlling spoilage factors through a good level of hygiene during processing and preservation techniques may contribute to a substantial reduction of TVB‐N. Trimethylamine (TMA) constitutes a significant part of TVB‐N. TMA and trimethylamine oxide (TMA‐N‐O) have been related to the pathogenesis of noncommunicable diseases, including atherosclerosis, cancers, and diabetes. Proposed methods for mitigation of TMA and TMA‐N‐O accumulation are discussed, which include a reduction in their daily dietary intake, control of internal production pathways by targeting gut microbiota, and inhibition of flavin monooxygenase 3 enzymes. The levels of TMA and TMA‐N‐O have significant health effects, and this should, therefore, be considered when evaluating meat quality and acceptability. Agreed international values for TVB‐N and TMA in meat products are required. The role of feed, gut microbiota, and translocation of methylated amines to muscles in farmed animals requires further investigation. [ABSTRACT FROM AUTHOR]

In the nematode Caenorhabditis elegans, signals derived from bacteria in the diet, the animal's major nutrient source, can modulate both behavior and healthspan. Here we describe a dual role for trimethylamine (TMA), a human gut flora metabolite, which acts as a nutrient signal and a neurotoxin. TMA and its associated metabolites are produced by the human gut microbiome and have been suggested to serve as risk biomarkers for diabetes and cardiovascular diseases. We demonstrate that the tyramine receptor TYRA‐3, a conserved G protein‐coupled receptor (GPCR), is required to sense TMA and mediate its responses. TMA activates guanylyl cyclase DAF‐11 signaling through TYRA‐3 in amphid neurons (ASK) and ciliated neurons (BAG) to mediate food‐sensing behavior. Bacterial mutants deficient in TMA production enhance dauer formation, extend lifespan, and are less preferred as a food source. Increased levels of TMA lead to neural damage in models of Parkinson's disease and shorten lifespan. Our results reveal conserved signaling pathways modulated by TMA in C. elegans that are likely to be relevant for its effects in mammalian systems. [ABSTRACT FROM AUTHOR]

The genus Sargassum is well represented by benthic and pelagic species, some of which form massive aggregates that can travel long distances due to the force of the ocean currents. Although they constitute an essential habitat for fish and invertebrate species, large accumulations of Sargassum in coastal areas generate several economic, environmental, and health impacts. It is important to recognize the species forming these aggregates, and identify the metabolites they produce, allowing for its exploitation, and therefore, better management practices. NMR metabolic profiling is a technique that can discriminate samples while detecting their unique or differential chemical features, and has been successfully used in the study and classification of several algal species. The present investigation studied the metabolic profiling of Sargassum species found on strandings at Puerto Morelos (Quintana Roo) east coast of the Mexican Caribbean. PCA of the 1H‐NMR profiles corresponding to S. natans, S. natans (morphotype VIII), S. fluitans, and a benthic Sargassum buxifolium allowed the discrimination of samples amongst them. Furthermore, discrimination between the two forms of S. natans was also possible. The PCA loading plot revealed that glutamine and glutamate have the highest influence in the clustering of the benthic Sargassum, while a high abundance of lactate, Myo‐inositol, and trimethylamine is a unique feature from the S. natans morphotype VIII. Additional PLS‐DA models showed that a heat‐drying process improved the extraction of metabolites. Maceration and microwave‐assisted extraction with water‐ethanol led to similar profiles and thus any of them could be used in future investigations. [ABSTRACT FROM AUTHOR]

The effects of trimethylamine N‐oxide (TMAO) on guanidinium chloride and hydrogen‐bonded networks of water are explored in this joint Raman spectroscopic and quantum chemical study. Both TMAO and guanidinium are osmolytes that affect the stability of proteins, as TMAO is known to stabilize and counteract the destabilizing effects of guanidinium. While guanidinium is very similar in chemical structure to urea, the exact mechanisms of the molecular interactions between guanidinium, TMAO, and proteins continue to be investigated. Herein, we use Raman spectroscopy to elucidate the physical interactions between TMAO and guanidinium in aqueous solutions to better understand how these important osmolytes interact with each other and affect adjacent hydrogen‐bonding networks of water. Comparing experiment to theory yields good agreement and allows for the identification and tracking of different vibrational modes. It was determined that adding TMAO into an aqueous solution of guanidinium induces a blue shift (shift to higher energy) in guanidinium's H‐N‐H bending modes, which is indicative of direct interactions between the two osmolytes and similar to the earlier results observed for TMAO interacting with urea. [ABSTRACT FROM AUTHOR]

The use of cosolutes and high hydrostatic pressure has been described as an efficient means to modulate the stability of enzymes and their catalytic activity. Cosolvents and pressure can lead to increased reaction rates without compromising the stability of the enzyme. Inspired by the multi‐component nature of the crowded cellular milieu of biological cells of piezophiles, we studied the combined effects of macromolecular crowding agents, different types of cosolvents and pressure in concert on a hydrolysis reaction catalyzed by α‐chymotrypsin. We have seen that crowding agents and cosolvents can have very diverse effects on enzymatic activity. Addition of the deep‐sea osmolyte trimethylamine‐N‐oxide displays by far the most positive effect on the catalytic efficiency, keff, of the reaction, which is even markedly enhanced at high pressures. Addition of the chaotropic agent urea leads to the reverse effect, and PEG and dextran as two representative crowding agents of a different nature show nearly similar values for keff compared to the pure buffer data. Such information may not only be relevant for understanding life processes in extreme environments, but also for the use of enzymes in industrial processing, which often requires harsh conditions as well. [ABSTRACT FROM AUTHOR]

The development of gut microbiota‐targeted small molecules represents a promising platform for the identification of new therapeutics based on the implication of human gut bacteria with different diseases. Bacterial trimethylamine (TMA)‐lyase (CutC) is expressed in gut bacteria and catalyzes the conversion of choline to TMA. The association of elevated TMA production with various disorders has directed research efforts toward identification of CutC inhibitors. Herein, we introduce peptidomimetics as a promising toolbox for the discovery of CutC inhibitors. Our approach starts with screening a library of peptidomimetics for intestinal metabolic stability followed by in vitro CutC inhibition. Compound 5 was identified from this screening platform with IC50 value of 5.9 ± 0.6 μM for CutC inhibition. Unlike previously reported CutC inhibitors, compound 5 possessed universal CutC inhibitory activity in different bacterial strains. Molecular dynamics simulations suggested a plausible binding site and inhibition mechanism for compound 5. Therefore, compound 5 is a promising lead for further structural optimization in the search for CutC‐targeted small molecules. [ABSTRACT FROM AUTHOR]

Trimethylamine N‐oxide (TMAO) is produced from the phosphatidylcholine metabolism of gut flora and acts as a risk factor of cardiovascular disease. However, the underlying mechanisms for its proatherogenic action remain unclear. This study aimed to observe the effect of TMAO on endothelial cell pyroptosis and explore the underlying mechanisms. Our results showed that TMAO promoted the progression of atherosclerotic lesions in apolipoprotein E‐deficient (apoE−/−) mice fed a high‐fat diet. Pyroptosis and succinate dehydrogenase complex subunit B (SDHB) upregulation were detected in the vascular endothelial cells of apoE−/− mice and in cultured human umbilical vein endothelial cells (HUVECs) treated with TMAO. Overexpression of SDHB in HUVECs enhanced pyroptosis and impaired mitochondria and high reactive oxygen species (ROS) level. Pyroptosis in the SDHB overexpression of endothelial cells was inhibited by the ROS scavenger NAC. In summary, TMAO promotes vascular endothelial cell pyroptosis via ROS induced through SDHB upregulation, thereby contributing to the progression of atherosclerotic lesions. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to investigate whether ethnicity influences the associations between trimethylamine N‐oxide (TMAO) levels and heart failure (HF) outcomes. Methods and results: Trimethylamine N‐oxide levels were measured in two cohorts with acute HF at two sites. The UK Leicester cohort consisted mainly of Caucasian (n = 842, 77%) and South Asian (n = 129, 12%) patients, whereas patients in the Japanese cohort (n = 116, 11%) were all Japanese. The primary endpoint was the measurement of all‐cause mortality and/or HF rehospitalization within 1 year post‐admission. Association of TMAO levels with outcome was compared in the entire population and between ethnic groups after adjustment for clinical parameters. TMAO levels were significantly higher in Japanese patients [median (interquartile range): 9.9 μM (5.2–22.8)] than in Caucasian [5.9 μM (3.6–10.8)] and South Asian [4.5 μM (3.1–8.4)] (P < 0.001) patients. There were no differences in the rate of mortality and/or HF rehospitalization between the ethnic groups (P = 0.096). Overall, higher TMAO levels showed associations with mortality and/or rehospitalization after adjustment for confounders (P = 0.002). Despite no differences between ethnicity and association with mortality/HF after adjustment (P = 0.311), only in Caucasian patients were TMAO levels able to stratify for a mortality/HF event (P < 0.001). Conclusions: Differences were observed in the association of mortality and/or rehospitalization based on circulating TMAO levels. Elevated TMAO levels in Caucasian patients showed increased association with adverse outcomes, but not in non‐Caucasian patients. [ABSTRACT FROM AUTHOR]

[N,N‐bis(1‐methyl‐2‐benzimidazolyl)methyl‐N‐(bis‐2‐pyridylmethyl)amine] (L1) and [N,N‐bis(2‐quinolylmethyl)‐N‐bis(2‐pyridyl)methylamine] (L2) were employed to prepare CuII and CuI complexes for spectroscopic and structural characterization. [L1CuII(H2O)](NO3)2 and [L2CuII(NO3)]NO3 have Jahn–Teller distorted octahedral geometries and give rise to isotropic EPR spectra in frozen solution. [L1CuI(CH3CN)]OTf and [L2CuI(CH3CN)]OTf have distorted trigonal bipyramidal and tetrahedral solid‐state structures, respectively. The N‐donors display labile behavior in solution, based on variable‐temperature 1H NMR studies. Addition of trimethylamine N‐oxide (Me3NO) to solutions of [L1CuI(CH3CN)]OTf and [L2CuI(CH3CN)]OTf resulted in diamagnetic species tentatively assigned as the corresponding adducts upon replacement of coordinated acetonitrile, based on 1H NMR spectroscopy. Heating [L1CuI(CH3CN)]OTf to 50–60 °C in the presence of Me3NO resulted in its cupric analogue [L1CuII(CH3CN)]2+, as well as a small amount of 2‐dipyridylketone, along with other oxidation by‐products. In the case of [L2CuI(CH3CN)]OTf, the reaction with Me3NO resulted in the cupric complex bis(2‐quinolinecarboxamidato)copper(II), along with 2‐dipyridylketone as oxidation products. [ABSTRACT FROM AUTHOR]

Translocation of microbiome‐derived lipopolysaccharide (LPS) to the bloodstream (metabolic endotoxaemia) is associated with a significantly increased risk of cardiovascular diseases (CVD); however, the direction of this association is not fully understood. It has been revealed by some studies that alterations in the intestinal microbiota (dysbiosis) lead to increased intestinal permeability and translocation of LPS to the blood circulation. LPS may trigger toll‐like receptor 4‐ (TLR‐4) mediated inflammatory responses; this could lead to a chronic low‐grade pro‐inflammatory condition named metabolic endotoxaemia (ME), which is typically observed in CVD patients. ME is promoted by increased intestinal permeability. Moreover, dysbiosis leads to production of trimethylamine‐N‐oxide (TMAO), a gut bacterial metabolite suggested as a new risk factor in CVD development. Probiotics, extensively reviewed for decades, are live microorganisms which, when taken in adequate amounts, have beneficial effects on the host metabolism. Prebiotics are a type of dietary fibre that act as nourishment for the good bacteria in the gut and decrease the population of pathogen bacteria that produce greater amounts of endotoxins. Although an association has been postulated between ME and CVD, the results of studies investigating the role of antibiotic therapy in preventing the disease have been inconsistent. In this review, we discuss how prebiotics and probiotics modulate gut microbiota and consequently might help with prevention and/or treatment of CVD associated with ME. [ABSTRACT FROM AUTHOR]

Trimethylamine (TMA) is a metabolite overtly present in patients suffering from trimethylaminuria (TMAU), a rare genetic disorder characterized by a strong "fishy" body odor. To date, no approved pharmacological treatment to sequester excess TMA on the skin of patients exists. Here, transmembrane pH gradient poly(isoprene)‐block‐poly(ethylene glycol) (PI‐b‐PEG) polymersomes are investigated for the topical removal of TMA. PI‐b‐PEG amphiphiles of varying chain length are synthesized and evaluated for their ability to form vesicular structures in aqueous media. The optimization of the PI/PEG ratio of transmembrane pH gradient polymersomes allows for the rapid and efficient capture of TMA both in solution and after incorporation into a topical hydrogel matrix at the pH of the skin. A subsequent double blind olfactory study reveals a significant decrease in perceived odor intensity after application of the polymersome‐based formulation on artificial skin substrates that has been incubated in TMA‐containing medium. This simple and novel approach has the potential to ease the burden of people suffering from TMAU. [ABSTRACT FROM AUTHOR]

The thermal decomposition of PH2BH2·NMe3 (1) in closed system was studied by static tensimetry with membrane null‐manometer. Compound 1 is unstable already at room temperature and partially decomposes with the release of gaseous trimethylamine and nonvolatile polymeric material. Storage of 1 at 311 K for 53 days results in evolution of small amounts of hydrogen and phosphine. At temperatures up to 329 K, PH3 evolution and BH3NMe3 adduct formation is observed after 3 days, and above 387 K, considerable amount of hydrogen gas is released. The data obtained indicate that the pyrolysis of 1 in the closed system may result in the enrichment of the condensed phase with boron due to phosphine loss. [ABSTRACT FROM AUTHOR]

Plant invasion can strongly influence carbon (C) cycling processes, thus it may affect climate change by altering C sequestration and greenhouse gas emissions in the invaded ecosystem. Since 1979, the exotic Spartina alterniflora has rapidly expanded in China's coastal areas, where significant increase in methane (CH4) emissions has been documented from post‐invaded sites. However, a mechanistic understanding of the structural and functional changes of associated methanogens accompanying this invasion remains elusive.Here we conducted integrated biogeochemical investigations on methanogenic substrates, activity, and diversity to identify implications of S. alterniflora invasion for methanogenesis in coastal wetlands. To do this, we collected and analysed 0–50 cm soil profiles from an uncolonised tidal flat (TF) and salt marshes that S. alterniflora has invaded for 1 year (SA‐1) and 12 years (SA‐12) in Jiangsu, China. Methanogenic community composition was characterised by massive parallel sequencing. The rates and pathways of methanogenesis were determined by adding trace concentrations of 13C‐labelled substrates to anaerobic incubated samples.Our results revealed that 12‐year invasion of S.alterniflora drastically increased CH4 production potential by one order of magnitude over that of TF. This substantial increase was primarily attributed to methanogenesis from trimethylamine; its rates increased by two orders of magnitude over TF whereas those from acetate and H2/CO2 increased far less. Hydrogenotrophic methanogenesis was the dominant pathway operating in the TF, but methanotrophic pathway contributed most to CH4 production in the surface layer of SA‐1 and uppermost 40‐cm layers of SA‐12. Consistent with these observations, the dominant methanogens shifted from obligate hydrogenotrophic Methanococcales in TF to potential methylamine‐utilising Methanosarcinaceaein SA‐12. Our Mantel analysis indicated that 'non‐competitive' trimethylamine, derived from cytoplasmic osmolytes of S. alterniflora, was the major driver of this change in methanogenic community composition.Synthesis. Our results suggest that invasive Spartina alternifloraplants gradually facilitated the local dominance of methylotrophic Methanosarcinaceae by changing the key type of methanogenic substrate in coastal marshes. Shifts in methanogen communities and enhanced availability of trimethylamine elevated the rates and importance of methylotrophic methanogenesis, thereby markedly increasing CH4 production potential and emission rates in this type of ecosystem. [ABSTRACT FROM AUTHOR]

BACKGROUND: Small‐scale farmers often take a double hit from pests such as tephritid fruit‐flies. The high price of products against fruit‐flies, together with the higher risk of reinfestation from neighboring orchards, limits options for control. Therefore, management requires low‐cost local products and concerted action. Peach production in central Bolivia is increasingly affected by invasive Ceratitis capitata. To provide locally sustainable techniques that could incentivize area‐wide cooperation of growers, we tested efficiency and specificity of low‐cost lures and traps compared with commercial lures and traps (Tephritrap). RESULTS: In the laboratory, the local fermented beverage 'chicha' and baker's yeast were equally or more attractive than commercial lures. Both chicha and baker's yeast trapped more flies in field (average FTD 10.31 and 9.49), whereas commercially hydrolyzed protein lure (4.71) or Torula yeast (6.82). However, many non‐target species were caught (57.3% and 53.4%). Of the six PET bottles‐based traps used, the T‐trap caught a similar number of flies (average FTD 5.55), but fewer beneficial insects (0.16) compared to the Tephritrap (0.92). CONCLUSIONS: This study provides fruit growers with an economical and effective method to capture large numbers of C. capitata, suitable to be part of integrated pest management programs for fruit fly control. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Time‐resolved pump–probe gas‐phase X‐ray scattering signals, extrapolated to zero momentum transfer, provide a measure of the number of electrons in a system, an effect that arises from the coherent addition of elastic scattering from the electrons. This allows to identify reactive transients and determine the chemical reaction kinetics without the need for extensive scattering simulations or complicated inversion of scattering data. We examine the photodissociation reaction of trimethylamine and identify two reaction paths upon excitation to the 3p state at 200 nm: a fast dissociation path out of the 3p state to the dimethyl amine radical (16.6±1.2 %) and a slower dissociation via internal conversion to the 3s state (83.4±1.2 %). The time constants for the two reactions are 640±130 fs and 74±6 ps, respectively. Additionally, it is found that the transient dimethyl amine radical has a N−C bond length of 1.45±0.02 Å and a C−N−C bond angle of 118°±4°. [ABSTRACT FROM AUTHOR]

ZnO and PdO‐decorated ZnO flower‐like structures have been synthesized using a facile one‐step hydrothermal method followed by subsequent calcination. Then, their structural information and trimethylamine (TMA) sensing performance were investigated. The results exhibited that the diameter of these ZnO flower‐like structures was in the range of 3–7 μm. Its morphology was maintained after introducing PdO nanoparticales. By comparing the sensing properties, it is found that sensors based on PdO‐decorated ZnO flower‐like structures showed higher TMA response than that of pure one. Especially, the sensor fabricated by 1 mol% PdO‐decorated ZnO flower‐like structures displayed superior gas sensing performances including high response, rapid response/recover characteristics, good stability, and high selectivity. Such a superior sensing performance is mainly due to the chemical and electrical sensitization of PdO nanoparticles. This simple synthesis strategy and a desirable TMA sensing performance could be broadly developed other metallic doped metal oxide flower‐like structures as high performance sensing materials. PdO‐decorated ZnO flower‐like structures self‐assembled with porous nanosheets were synthesized by a facile one‐step hydrothermal method, which displayed superior TMA gas sensing performances including high response, rapid response/recover characteristics, good stability and reproducibility, and high selectivity. This simple process for synthesizing PdO‐decorated ZnO flower‐like structures would be further expanded to develop other metallic doped metal oxide flower‐like structures as high performance sensing materials. [ABSTRACT FROM AUTHOR]

Summary: Trimethylamine (TMA) is common in marine environments. Although the presence of this compound in the oceans has been known for a long time, unlike the mammalian gastrointestinal tract, where TMA metabolism by microorganisms has been studied intensely, many questions remain unanswered about the microbial metabolism of marine TMA. This minireview summarizes what is currently known about the sources and fate of TMA in marine environments and the different pathways and enzymes involved in TMA metabolism in marine bacteria. This review also raises several questions about microbial TMA metabolism in the marine environments and proposes potential directions for future studies. [ABSTRACT FROM AUTHOR]

Coordination polymer microrods of [Cu(μ2‐L)(H2O)]n (CuL) (H2L = thiazolidine‐2,4‐dicarboxylic acid) were synthesized via a simple and versatile precipitation method at room temperature. Chemiresistive sensory devices based on these CuL microrods were prepared to investigate the gas sensing performance for the first time. The CuL microrod gas sensor exhibits reliable linear response towards trimethylamine (TMA) vapor at 95 °C with high response, fast response‐recovery, and good selectivity. Notably, as low as 1 ppm TMA can be well detected with high response value (Sr = 9.2). This work provides an ideal candidate material for monitoring TMA vapor and further develops a new promising application for coordination polymer micro‐/nano‐structures. [ABSTRACT FROM AUTHOR]

As one kind of functionalized green medium, chiral ionic liquids (CILs) have been widely applied in fields of asymmetric catalysis, enantioseparation, and so on. In this study, four kinds of amino acid–based CILs were synthesized by using trimethylamine, N‐methylpyrrolidine, N‐methylimidazole, and tropine as cationic nucleus, respectively. Then their specific optical rotation and solubility in common solvents were determined for further resolution application. The effect of different cations in these CILs was explored on the separation of racemic phenylalanine in complex‐precipitation way. Moreover, various factors were systematically investigated for their effects on resolution efficiency, including the type of additive copper salts, the molar ratio of Cu (II) to CIL, pH value, the amount of racemic phenylalanine, and temperature. Under the appropriate conditions, L‐phenylalanine mainly existed in solid phase and could be separated from its enantiomers in liquid phase. Furthermore, the mechanism of resolution was studied by thermogravimetric analysis, infrared spectrum, and molecular simulation. The resolution system has characteristics of no organic solvent, fast separation speed, simple resolution process, and easy scale‐up. [ABSTRACT FROM AUTHOR]