Screening gut microbial trimethylamine production by fast and cost-effective capillary electrophoresis

Abstract

The present work is aimed to develop and validate a simple, rapid and cost-effective CE method for the determination of trimethylamine (TMA) from bacterial origin. Optimum Sseparation of TMA from the other components of the bacterial culture was achieved in less than 1.1 min using a fused silica capillary (27 cm × 75 μm ID) and a background electrolyte solution that consisted of formic acid (0.75 M at pH 2.05). Analytical characteristics of the proposed method The proposed method was validatedwere evaluated through the study of by testing its specificity, linearity, precision, accuracy, recoveryrobustness, and detection limit/quantitation limit values.The method was linear over the range 25-2000 M (R 2 = 0.999864). The LOD and LOQ were 9 µM and 27 µM, respectively. Intra-day and inter-day RSD were ⩽0.24% and ⩽1.3% for migration time, respectively. Intra-day and inter-day RSD for peak area were ⩽2.44% and ⩽3.51%, respectively. The method showed a good accuracy with recovery percentages ranging from 95.45% to 102.21%. The validated method was successfully applied for the determination of microbial conversion of L-carnitine to TMA. The method shows great potential in highthroughput screening applications to assess the functionality of the gut microbiota to produce TMA.

Resazurin-based high-throughput screening method for the discovery of dietary phytochemicals to target microbial transformation of l-carnitine into trimethylamine, a gut metabolite associated with cardiovascular disease

“…This strain harbours functional CntAB and was able to produce a significant amount of TMA when cultivated in the presence of l -carnitine. 21 The bacterial isolate was maintained at −80 °C in 10% w/v glycerol in a brain–heart infusion (BHI) media. K. pneumoniae cells were grown aerobically at 37 °C in a defined chemical medium (DM) based on the medium described previously 7 with some modifications, having the following composition: 1 g L −1 NH 4 Cl, 0.5 g L −1 NaCl, 3 g L −1 KH 2 PO 4 , 17.1 g L −1 Na 2 HPO 4 ·12H 2 O, 0.6 mg L −1 Na 2 MoO 4 ·2H 2 O, 0.22 g L −1 CaCl 2 ·6H 2 O, 50 μM FeCl 3 , 0.24 g L −1 MgSO 4 , 0.02 mg L −1 biotin, 0.02 mg L −1 folic acid, 0.1 mg L −1 pyridoxine hydrochloride, 0.05 mg L −1 thiamine hydrochloride, 0.05 mg L −1 riboflavin, 0.05 mg L −1 nicotinic acid, 0.05 mg L −1 pantothenic acid, 0.001 mg L −1 vitamin B12, 0.05 mg L −1 4-aminobenzoic acid, and 0.05 mg L −1 lipoic acid.…”

“…TMA was determined in the growth medium by capillary electrophoresis with the UV detection (CE-UV) method as described previously. 21 Briefly, the bacterial culture or bacterial lysate was mixed with derivatizing agent 80 mm 2,4′-dibromoacetophenone (1 : 3, v/v) in a 2 ml tube, and incubated at 70 °C for 60 min. The derivatized sample was evaporated using a nitrogen stream or vacuum concentrated with SpeedVac to dryness.…”

Electrophoretic Determination of Trimethylamine (TMA) in Biological Samples as a Novel Potential Biomarker of Cardiovascular Diseases Methodological Approach

“…The derivatization process described by García-Cañas et al [ 34 ] was applied in our study with slight modifications. The reaction between DBA and TMA was performed to obtain the maximum yield of the product in the shortest reaction time.…”

“…The use of pseudo stationary phases rather than true stationary phases in the CE-based methods reduces problems with irreproducibility between capillaries, and, furthermore, it is simpler than introducing selectivity via the more time-consuming process of the immobilization of nanomaterials to form inner capillary wall coatings [ 31 , 32 , 33 ]. Screening gut microbial trimethylamine production by fast and cost-effective capillary electrophoresis was also utilized by García-Cañas et al [ 34 ].…”

Prebiotic effect of fructans from Agave salmiana on probiotic lactic acid bacteria and in children as a supplement for malnutrition

“…As the functionality of the gut microbiota is an important factor to evaluate its eubiosis, the level of TMA from bacterial origin is of special interest as a biomarker, since TMA is a metabolite produced by various taxa in the gut microbiota. 38 The decrease of TMA is a beneficial effect, considering that TMA is absorbed in the intestine and then incorporated into the liver, where it is oxidized to produce trimethylamine N-oxide, which has been implicated as a risk factor for cardiovascular disease. 39 The adverse effect of the other compounds has been reported.…”