Using Ultra-high Performance Liquid Chromatography Research Articles

A Fully Validated LC-MS Quantitation Method for Psychoactive Compounds Found in Native South American Plant Species

Psychoactive drugs are compounds that alter the function of the central nervous system, resulting in changes in perception, mood, cognition, and behavior. A subclass of psychoactive drugs, psychedelics, are hallucinogenic drugs that can trigger psychedelic experiences and possible changes in mental perception. The potential use of psychedelics as a therapeutic has led to an increase in clinical research focusing on the treatment of mental disorders including anxiety and depression. There are numerous species belonging to Psychotria and Banisteriopsis which have been reported to contain psychedelic and psychoactive compounds; however, there is a lack of validated analytical methods for raw plant material, which is crucial if these plants are to be commercially cultivated for medicines. This study provides a fully validated method using ultra-high performance liquid chromatography (UHPLC) coupled to mass spectrometry (MS) for the following six compounds: tryptamine, N,N-dimethyltryptamine (DMT), 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT), tetrahydroharmine (THH), harmaline, and harmine. The validated method was used to determine the psychoactive concentrations in Psychotria viridis, Psychotria carthagenensis, Banisteriopsis caapi, and Alicia anisopetala. Validation parameters were established; linearity (R2 = 0.988–0.999), limit of detection (LOD) (0.06–0.11 ng/mL), limit of quantitation (LOQ) (0.18–0.34 ng/mL), accuracy, precision, extraction efficiency (>98%), recovery (74.1–111.6%), and matrix effect (70.6–109%) were all evaluated. All six compounds eluted within nine minutes, with a total analysis time of 20 min including column equilibration. This method establishes a high-throughput method for the robust analysis of psychedelics which may see future use in agricultural research and industry.

Efficient Simultaneous Isolation of Pinostrobin and Panduratin A from Boesenbergia rotunda Using Centrifugal Partition Chromatography.

The bioactive flavonoids pinostrobin (PN) and panduratin A (PA) from Boesenbergia rotunda are essential for research and therapeutic applications. This study introduces an innovative method utilizing ultrasound-assisted extraction with n-hexane pre-treatment, followed by one-step centrifugal partition chromatography (CPC) purification. Extraction efficiency was evaluated using ultra high-performance liquid chromatography (UHPLC), and the isolated compounds were characterized through 1H-NMR and liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), adhering to AOAC validation guidelines. Optimal extraction conditions comprised a particle size of 125 μm, a solid-to-liquid ratio of 1:30 g/mL, and a 10 min extraction time, yielding a crude extract of 6.96 ± 0.07%. Using an n-hexane/MeOH/water (5/3.4/1.6, v/v) solvent system in ascending mode, PN (2.16 mg, 98.78% purity) and PA (0.4 mg, 99.69% purity) were isolated from 67 mg of crude extract within 30 min. This streamlined approach enhances purification efficiency, allowing for faster extraction and higher purity, making it a suitable method for commercial applications.

AF4-UHPLC: Two-dimensional separation of macromolecules in four white wines from South-Western France

Proteins in wines contribute to “protein haze,” which, while not affecting health or taste, can detract from the visual appeal of wines to consumers. To mitigate this issue, winemakers commonly use fining agents such as bentonite, despite the high costs involved. To overcome these challenges, numerous studies employ various analytical methods to better understand the behaviour of proteins. A novel technique which separates compounds by size, Asymmetrical Flow-Field Flow Fractionation (AF4), allows for studying proteins without denaturing them. Given that most proteins share similar sizes, identification remains challenging. The aim of this work was initially to develop a new system enabling simultaneous analysis of the macromolecular profile of wines (proteins, mannoproteins) using AF4 and real-time protein nature analysis (hydrophobicity properties) using Ultra-High Performance Liquid Chromatography (UHPLC). By injecting two standards of different sizes and chemical nature, thaumatin protein and mannoproteins, the system was validated. The subsequent application of this system to Southwestern wines revealed distinct profiles across monovarietal white wines from four grape varieties. While the Colombard (COL) and Gros manseng (GM) varieties showed similar protein compositions with varying concentrations, the Len de l'el (LL) variety had only two types of protein and no protein was detected in the Mauzac (MZ) variety. Despite these variations, all varieties contained mannoproteins. This system shows promise for studying wine protein composition and could potentially find applications in other matrices.

Phytochemical composition analysis, antioxidant, antimitotic, and anti-inflammatory effects of leaf and stem extracts of Pistacia lentiscus L

ABSTRACT This study explored the phytochemical composition, antioxidant properties, anti-germinative effects, and anti-inflammatory actions of methanolic leaf extracts (MLE) and methanolic stem extracts (MSE) derived from Pistacia lentiscus L. species native to the eastern region of Morocco. Using Ultra-high-performance liquid chromatography (UHPLC),16 and 17 components were discovered inMLE and MSE, respectively, with Epigallocatechin being the most prevalent in both extracts. Polyphenols and flavonoids were found to be more abundant in MLE. Furthermore, DPPH assays revealed that it had a higher free radical scavenging activity (IC50 = 37.5 mg/L) compared to ascorbic acid while ferric-reducing power tests showed that MSE had a greater potency (IC50 = 86.14 mg/L) than MLE. Both MLE and MSE inhibited sorghum seed germination in a dose-dependent manner, with MSE being slightly more effective. Mitotic index determination revealed that both extracts had concentration-dependent antimitotic effects, with MSE showing similarity to colchicine, indicating its potential as an antimitotic agent. In vitro, anti-inflammatory assays showed that it had similar properties to indomethacin in protein denaturation and membrane stabilization, while MLE displayed distinct characteristics. Furthermore, in a carrageenan-induced rat model, both extracts demonstrated anti-inflammatory potential, with MSE showing a trend of slightly better efficacy. These results highlight the importance of further investigation into MSE’s potential as an anti-inflammatory and antimitotic agent.

Development of an untargeted DNA adductomics method by ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry

Genotoxicants originating from inflammation, diet, and environment can covalently modify DNA, possibly initiating the process of carcinogenesis. DNA adducts have been known for long, but the old methods allowed to target only a few known DNA adducts at a time, not providing a global picture of the “DNA adductome”. DNA adductomics is a new research field, aiming to screen for unknown DNA adducts by high resolution mass spectrometry (HRMS). However, DNA adductomics presents several analytical challenges such as the need for high sensitivity and for the development of effective screening approaches to identify novel DNA adducts. In this work, a sensitive untargeted DNA adductomics method was developed by using ultra-high performance liquid chromatography (UHPLC) coupled via an ESI source to a quadrupole-time of flight mass spectrometric instrumentation. Mobile phases with ammonium bicarbonate gave the best signal enhancement. The MS capillary voltage, cone voltage, and detector voltage had most effect on the response of the DNA adducts. A low adsorption vial was selected for reducing analyte loss. Hybrid surface-coated analytical columns were tested for reducing adsorption of the DNA adducts. The optimized method was applied to analyse DNA adducts in calf thymus, cat colon, and human colon DNA by performing a MSE acquisition (all-ion fragmentation acquisition) and screening for the loss of deoxyribose and the nucleobase fragment ions. Fifty-four DNA adducts were tentatively identified, hereof 38 never reported before. This is the first untargeted DNA adductomics study on human colon tissue, and one of the few untargeted DNA adductomics studies in the literature reporting the identification of such a high number of unknowns. This demonstrates promising results for the application of this sensitive method in future human studies for investigating novel potential cancer-causing factors.

Revealing the sterilization impact on paprika fingerprint: Key markers identified using untargeted metabolomics by liquid chromatography-Orbitrap high-resolution mass spectrometry

Paprika (Capsicum annuum L.) is a popular spice known for its unique properties. Spices are susceptible to microbiological risks arising from harvest factors such as high moisture or environmental contamination. To ensure microbiological safety, post-harvest processing based on heat sterilization, free of chemicals and radiation, is becoming essential in the European market. This study introduces a novel metabolomics approach using ultra-high performance liquid chromatography (UHPLC) coupled with quadrupole-Orbitrap-high-resolution mass spectrometry (HRMS) to assess the sterilization impact on paprika's metabolomic composition. Sterilized and untreated samples were distinguished by OPLS-DA, achieving perfect predictability with high-quality parameters (R2Y = 0.988, Q2 = 0.904). The methodology identified 19 key markers, including fatty acids, amino acids, etc. Sterilization reduced fatty acids such as linoleic acid but increased other metabolites such as DL-malic acid and flazin. This research introduces new metabolomics strategies to ensure paprika quality and other valuable spices, focusing on unexplored sterilization processes.

Quantitation of trace polyfunctional thiols in wine by liquid chromatography quadrupole Orbitrap high-resolution mass spectrometry in parallel reaction monitoring

Polyfunctional thiols are key contributors to wine aroma due to their extremely low odor thresholds, and their quantitative analysis remains challenging as a result of their ultratrace concentrations and high reactivity. This work presents the first method based on ultra-high-performance liquid chromatography (UHPLC) coupled to quadrupole Orbitrap high-resolution mass spectrometry (HRMS) in parallel reaction monitoring (PRM) mode for quantifying thiols at nanograms per liter (ng/L) levels in wine. Thiols in wine were derivatized using 4,4′-dithiodipyridine and isolated by liquid-liquid extraction. This protocol allowed rapid sample preparation with minimum labor input and low consumable expenses. Instrumental analysis was conducted using UHPLC–quadrupole Orbitrap HRMS in PRM mode. Twenty thiol analytes, including literature-known, recently identified, and novel thiols were selected and validated by the optimized method in three wine matrices. The overall analytical performances demonstrated by this method were equivalent, and in most cases, greater than many previously developed GC–MS or LC–MS methods. The validated method was applied to analyze a selection of wines in which 12 thiols were quantified.

Metabolomic and Lipidomic Analysis of Manganese-Associated Parkinsonism: a Case-Control Study in Brescia, Italy.

Excessive Manganese (Mn) exposure is neurotoxic and can cause Mn-Induced Parkinsonism (MnIP), marked by cognitive and motor dysfunction. Although metabolomic and lipidomic research in Parkinsonism (PD) patients exists, it remains limited. This study hypothesizes distinct metabolomic and lipidomic profiles based on exposure status, disease diagnosis, and their interaction. We used a case-control design with a 2×2 factorial framework to investigate the metabolomic and lipidomic alterations associated with Mn exposure and their link to PD. The study population of 97 individuals was divided into four groups: non-exposed controls (n=23), exposed controls (n=25), non-exposed with PD (n=26) and exposed with PD (n=23). Cases, defined by at least two cardinal PD features (excluding vascular, iatrogenic, and traumatic origins), were recruited from movement disorder clinics in four hospitals in Brescia, Northern Italy. Controls, free from neurological or psychiatric conditions, were selected from the same hospitals. Exposed subjects resided in metallurgic regions (Val Camonica and Bagnolo Mella) for at least 8 continuous years, while non-exposed subjects lived in low-exposure areas around Lake Garda and Brescia city. We conducted untargeted analyses of metabolites and lipids in whole blood samples using ultra-high-performance liquid chromatography (UHPLC) and mass spectrometry (MS), followed by statistical analyses including Principal Component Analysis (PCA), Partial Least Squares-Discriminant Analysis (PLS-DA), and Two-Way Analysis of Covariance (ANCOVA). Metabolomic analysis revealed modulation of alanine, aspartate, and glutamate metabolism (Impact=0.05, p=0.001) associated with disease effect; butanoate metabolism (Impact=0.03, p=0.004) with the exposure effect; and vitamin B6 metabolism (Impact=0.08, p=0.03) with the interaction effect. Differential relative abundances in 3-sulfoxy-L-Tyrosine (β=1.12, FDR p<0.001), glycocholic acid (β=0.48, FDR p=0.03), and palmitelaidic acid (β=0.30, FDR p<0.001) were linked to disease, exposure, and interaction effects, respectively. In the lipidome, ferroptosis (Pathway Lipids=11, FDR p=0.03) associated with the disease effect and sphingolipid signaling (Pathway Lipids=9, FDR p=0.04) associated with the interaction effect were significantly altered. Lipid classes triacylglycerols, ceramides, and phosphatidylethanolamines showed differential relative abundances associated with disease, exposure, and interaction effects, respectively. These findings suggest that PD and Mn exposure induce unique metabolomic and lipidomic changes, potentially serving as biomarkers for MnIP and warranting further study.

Fevogrit, a polyherbal medicine, mitigates endotoxin (lipopolysaccharide)-induced fever in Wistar rats by regulating pro-inflammatory cytokine levels.

Fever is characterized by an upregulation of the thermoregulatory set-point after the body encounters any pathological challenge. It is accompanied by uncomfortable sickness behaviors and may be harmful in patients with other comorbidities. We have explored the impact of an Ayurvedic medicine, Fevogrit, in an endotoxin (lipopolysaccharide)-induced fever model in Wistar rats. Active phytoconstituents of Fevogrit were identified and quantified using ultra-high-performance liquid chromatography (UHPLC) platform. For the in-vivo study, fever was induced in male Wistar rats by the intraperitoneal administration of lipopolysaccharide (LPS), obtained from Escherichia coli. The animals were allocated to normal control, disease control, Paracetamol treated and Fevogrit treated groups. The rectal temperature of animals was recorded at different time points using a digital thermometer. At the 6-h time point, levels of TNF-α, IL-1β and IL-6 cytokines were analyzed in serum. Additionally, the mRNA expression of these cytokines was determined in hypothalamus, 24 h post-LPS administration. UHPLC analysis of Fevogrit revealed the presence of picroside I, picroside II, vanillic acid, cinnamic acid, magnoflorine and cordifolioside A, as bioactive constituents with known anti-inflammatory properties. Fevogrit treatment efficiently reduces the LPS-induced rise in the rectal temperature of animals. The levels and gene expression of TNF-α, IL-1β and IL-6 in serum and hypothalamus, respectively, was also significantly reduced by Fevogrit treatment. The findings of the study demonstrated that Fevogrit can suppress LPS-induced fever by inhibiting peripheral or central inflammatory signaling pathways and could well be a viable treatment for infection-induced increase in body temperatures.

A comprehensive study of Chuanwang Xiaoyan capsule based on characterization of chemical constituents in vitro and in vivo using ultra-high-performance liquid chromatography-quadrupole-Exactive Orbitrap mass spectrometry and pharmacokinetic study of multiple components in rats using ultra-high-performance liquid chromatography-triple quadrupole-tandem mass spectrometry.

Chuanwang Xiaoyan (CWXY) capsule is primarily used to treat a variety of acute and chronic inflammations, including acute and chronic pharyngitis and tonsillitis. However, a systematic study of its chemical constituents is still not available. This study evaluated the chemical constituents in vitro and metabolite profiles in vivo of CWXY using ultra-high-performance liquid chromatography (UHPLC) coupled with Q-Exactive Orbitrap mass spectrometry, and the pharmacokinetic behaviors of the nine main components in rats were detected using ultra-high-performance liquid chromatography-triple quadrupole-mass spectrometry (UPLC-QQQ-MS/MS). A total of 92 chemical constituents in CWXY were preliminarily identified in vitro. After oral administration to rats, 56 prototype components and 128 metabolites of CWXY were detected in the biological samples of rat plasma, urine, bile, and feces. Of these prototype components and metabolites, seven new compounds, namely M15, M16, M25, M30, M31, M71, and M128, were detected for the first time. The quantitation method of nine components in rat plasma was developed using a pharmacokinetic study. To the best of our knowledge, this study was the first to investigate the pharmacokinetic behavior of triumbelletin.

Stability Studies of the Dilution Series of Different Antibiotic Stock Solutions in Culture Medium Incubated at 37 °C.

The long-term stability of antibiotics in culture media remains underexplored in scientific literature. This study evaluated the stability of eight distinct antibiotic stock solutions-amoxicillin, cefotaxime, neomycin, oxytetracycline, florfenicol, enrofloxacin, colistin, and potentiated sulfonamide-and their 10-fold dilution series in tryptone soy broth (TSB) at 37 °C, over 12 days. Samples were collected immediately after preparation and on days 1, 2, 5, 7, 9, and 12, with active substance concentrations measured using ultra-high-performance liquid chromatography (UHPLC) coupled with mass spectrometry. The results indicated that among the ultrapure water stock solutions, neomycin, florfenicol, and potentiated sulfonamide maintained stability (>95%). Within the culture medium, florfenicol showed consistent stability (100%) throughout the study, potentiated sulfonamide experienced minor degradation (>85%), and neomycin underwent significant degradation. Amoxicillin, oxytetracycline, and colistin displayed considerable degradation in both solution types but were more stable in ultrapure water solutions. The stability of cefotaxime and enrofloxacin in ultrapure water solutions and in the medium was very similar when compared; however, 3.6% of the former and 88.7% of the latter remained detectable by day 12. These findings are crucial for minimum inhibitory concentration (MIC) assessments, especially in minimum bactericidal concentration (MBC) studies, and in experiments concerning long-term evolution and co-selection. This study underscores the necessity of stability assessments in culture media to validate future experimental outcomes.

Human metabolism of the semi-synthetic cannabinoids hexahydrocannabinol, hexahydrocannabiphorol and their acetates using hepatocytes and urine samples.

Hexahydrocannabinol (HHC), hexahydrocannabiphorol (HHCP) and their acetates, HHC-O and HHCP-O, respectively, are emerging in Europe as alternatives to tetrahydrocannabinol (THC). This study aimed to elucidate the metabolic pathways of the semi-synthetic cannabinoids HHC, HHCP, HHC-O and HHCP-O from incubation with human hepatocytes. The metabolites of HHC were also identified in authentic urine samples. HHC, HHCP, HHC-O and HHCP-O were incubated with primary human hepatocytes for 1, 3 and 5 h. Authentic urine samples from cases screened positive for cannabis in blood using ELISA but confirmed negative were analysed both non-hydrolysed and hydrolysed for HHC metabolites. Potential metabolites were identified using ultra-high performance liquid chromatography (UHPLC) coupled to a quadrupole time-of-flight mass spectrometer (QToF-MS). HHC and HHCP were primarily metabolised through monohydroxylation (monoOH), followed by oxidation to a carboxylic acid metabolite. HHC-O and HHCP-O were rapidly metabolised to HHC and HHCP, respectively. In authentic urine samples, 18 different metabolites were identified, and 99.3% of hydroxylated metabolites were glucuronidated. 11-OH-HHC, 5'OH-HHC and another metabolite with a monoOH on the side chain were the only metabolites present in all 16 urine samples. The metabolism of HHC and HHCP were similar, although the longer alkyl side chain of HHCP (heptyl) led to greater hydroxylation on the side chain than HHC (pentyl). The use of HHC and HHCP can be differentiated from the use of THC and other phytocannabinoids, but the use of the acetate analogues may not be differentiable from their non-acetate analogues.

Distribution of antibiotic resistance genes and antibiotic residues in drinking water production facilities: Links to bacterial community.

There is a rapid spread of antibiotic resistance in the environment. However, the impact of antibiotic resistance in drinking water is relatively underexplored. Thus, this study aimed to quantify antibiotic resistance genes (ARGs) and antibiotic residues in two drinking water production facilities (NW-E and NW-C) in North West Province, South Africa and link these parameters to bacterial communities. Physicochemical and ARG levels were determined using standard procedures. Residues (antibiotics and fluconazole) and ARGs were quantified using ultra-high performance liquid chromatography (UHPLC) chemical analysis and real-time PCR, respectively. Bacterial community compositions were determined by high-throughput 16S rRNA sequencing. Data were analysed using redundancy analysis and pairwise correlation. Although some physicochemical levels were higher in treated than in raw water, drinking water in NW-E and NW-C was safe for human consumption using the South African Water Quality Guideline (SAWQG). ARGs were detected in raw and treated water. In NW-E, the concentrations of ARGs (sul1, intl1, EBC, FOX, ACC and DHA) were higher in treated water than in raw water. Regarding antimicrobial agents, antibiotic and fluconazole concentrations were higher in raw than in treated water. However, in NW-C, trimethoprim concentrations were higher in raw than in treated water. Redundancy analysis showed that bacterial communities were not significantly correlated (Monte Carlo simulations, p-value >0.05) with environmental factors. However, pairwise correlation showed significant differences (p-value <0.05) for Armatimonas, CL500-29 marine group, Clade III, Dickeya and Zymomonas genera with environmental factors. The presence of ARGs and antibiotic residues in the current study indicated that antibiotic resistance is not only a clinical phenomenon but also in environmental settings, particularly in drinking water niches. Consumption of NW-E and NW-C treated water may facilitate the spread of antibiotic resistance among consumers. Thus, regulating and monitoring ARGs and antibiotic residues in drinking water production facilities should be regarded as paramount.

Study on pulp metabolism of patients with pulpitis using ultra-performance liquid chromatography coupled with Orbitrap mass spectrometry

Background and aimsPulpitis, a pulp disease caused by caries, trauma, and other factors, has a high clinical incidence. This study focused on identifying possible metabolic biomarkers of pulpitis cases and analyzing the related metabolic pathways for providing a theoretical foundation to diagnose and prevent pulpitis. Materials and methodsPulp samples from 20 pulpitis cases together with 20 normal participants were analyzed with a serum metabolomics approach using ultra-high-performance liquid chromatography (UPLC)/Orbitrap mass spectrometry. Moreover, this work carried out multivariate statistical analysis for screening potential biomarkers of pulpitis. ResultsThrough biomarker analysis and identification, such as partial least squares discrimination analysis, orthogonal partial least squares discriminant analysis model establishment, correlation analysis, and biomarker pathway analysis, 40 biomarkers associated with 20 metabolic pathways were identified, including 20 upregulated and 20 downregulated metabolites. Those major biomarkers included oxoglutaric acid, inosine, citric acid, and PA(14:1(9Z)/PGD1). Among them, oxoglutaric acid and inosine were most significantly downregulated and had the highest correlation with pulpitis. Among these metabolic pathways, GABAergic synapse and alanine, aspartate, and glutamate metabolism were positively correlated with pulpitis. 4. ConclusionsThese biomarkers as well as metabolic pathways may offer the theoretical foundation to understand pulpitis pathogenesis and develop preventive drugs.

Non-target analysis of crude oil photooxidation products at high latitudes and their biological effects

With new oil and gas lease sales in high-latitude regions, there exists a need to better understand the chemical fate of spilled oil and its effects on biological life. To address this need, laboratory simulations of crude oil spills under sub-Arctic conditions were conducted using artificial seawater and exposure to solar irradiation to create Hydrocarbon Oxidation Products (HOPs). HOPs characterization and their biological effects were assessed using ultra high-performance liquid chromatography (UHPLC) with high resolution mass Orbitrap spectrometry and the aryl hydrocarbon receptor (AhR) chemically activated luciferase gene expression (CALUX) assay. Non-target UHPLC-Orbitrap mass spectrometry analysis identified 251 HOPs that were in greater abundance in light-exposed samples than dark controls. Oxidized polycyclic aromatic hydrocarbons were also detected, including phenanthrene quinone, anthraquinone, hydroxyanthraquinone, and 9-fluoreneone. The composition of HOPs were consistent with photo-products of alkylated two to four ring PAHs, primarily compounds between 1 and 3 aromatic rings and 1–3 oxygens. The HOP mixture formed during photochemical weathering of Cook Inlet crude oil induced greater AhR activity than parent petroleum products solubilized in dark controls, indicating that HOPs, as a complex mixture, may contribute to petroleum toxicity more than the parent petroleum compounds. These non-targeted approaches provide the most comprehensive analysis of hydrocarbon oxidation products to date, highlighting the diversity of the complex mixture resulting from the photooxidation of crude oil and the limitations of targeted analyses for adequately monitoring HOPs in the environment. Taken together, these data identify a critical “blind spot” in environmental monitoring and spill clean-up strategies as there is a diverse pool of HOPs that may negatively impact human and ecosystem health.

Untargeted metabolomic profiling of 100% malt beers versus those containing barley adjunct

Why was the work done: The incorporation of unmalted barley at high proportion in the grist can introduce unfavourable bitter and astringent characteristics to beer, resulting in an upper limit on the proportion used. The flavour active compounds from raw barley which contribute these characteristics to the beer remain to be identified. How was the work done: This study used non-targeted metabolomics to determine non-volatile metabolites which could contribute to flavour differences when brewing with barley. Three beers were analysed using ultra-high performance liquid chromatography (UHPLC) coupled to a quadrupole time-of-flight mass spectrometer (qTOF) with an electro-spray ionisation source (ESI). One beer was produced using 100% malt and two beers with a grist of 15% barley and 85% malt (beers A and B). The barley was used untreated (beer A) or treated using a proprietary process (beer B). The metabolomic profiles of the three beers were compared and statistically different molecular features were annotated via analysis of MS2 spectra. What are the main findings: Several of the main differential molecular features were nitrogenous peptides and purine derivatives. This was attributed to the lack of the malting process and associated proteolytic enzyme activity reducing the extent of protein and peptide breakdown in the unmalted barley. Several of the identified peptides had amino acid residues which are known to cause bitter and kokumi (rich) taste in beer, which could explain the bitterness when brewing with unmalted barley. Why is the work important: A non-targeted approach offers new insights into non-volatile molecular features in beer that have not been previously identified with targeted analyses. Accordingly, this work identifies metabolites and groups of compounds which have not been previously considered when investigating the unfavourable bitterness and astringency associated with the use of unmalted barley

Electrochemical determination of salbutamol in aqueous solutions with UiO‐66/rGO‐modified electrodes

AbstractThe synthesis of the UiO‐66/rGO material involved combining UiO‐66 with reduced graphene oxide (rGO). This resulting composite found application in the electrochemical determination of salbutamol (SAL) through modification of a glassy‐carbon electrode (GCE) with UiO‐66/rGO. Differential pulse voltammetry served as the chosen technique, offering a wide linear range spanning 1–160 µm and demonstrating a low limit of detection at 0.84 µm. To ensure the reliability of the electrode, various aspects such as sensitivity, repeatability, reproducibility, and stability were meticulously studied. When applied to the analysis of SAL in swine urine solutions (n = 3), the electrode exhibited good recovery rates. Remarkably, the results obtained through this method correlated well with those acquired using ultra‐high performance liquid chromatography (UPLC).

Multi-pesticide residue screening, identification, and quantification analysis in various fruits and vegetables by UHPLC-Q Exactive HRMS.

A general strategy for qualitative screening and quantitative analysis of 403 pesticides in various fruits and vegetables was developed using ultrahigh-performance liquid chromatography (UHPLC) in conjunction with a Thermo Q Exactive Focus high-resolution mass spectrometer, relying on an executable compound database comprised of the exacted mass of precursor ions, retention times, and fragment ions. Taking advantage of the powerful separation capacity of UHPLC, an Orbitrap analyzer with high sensitivity in full scan mode and elevated mass resolution of product ions in the MS/MS mode, eight pairs of isomers and fifty-seven groups of isobaric compounds were selectively identified. The method was then systematically assessed and validated for eight fruits and vegetables, in terms of screening detection limit (SDL), matrix effects, recovery, and precision over 400 pesticides. The results showed that the SDLs of 68.0-84.4% for the pesticides were less than or equal to 10 μg kg-1 in the representative matrices, recoveries in the range of 60-120% accounting for 48.6-84.4% of all the targets at three lower fortified levels of 5, 20, and 50 μg kg-1 with a precision of less than 20% while the range of overall average recoveries for the majority of the pesticides were from 82.4% to 105.1% in the as-selected matrices with RSDs between 3.9% and 7.7%. Using this method, screening data from a survey of pesticide residues in 68 practical samples across 32 different matrix types provides scientific data for the inspection and supervision of pesticide residue safety of fruits and vegetables.

Determination of chiral prothioconazole and its chiral metabolite in water, juice, tea, and vinegar using emulsive liquid–liquid microextraction combined with ultra-high performance liquid chromatography

Emulsive liquid–liquid microextraction (ELLME), a simple, rapid, and environmentally friendly technique, was established to identify chiral prothioconazole and its chiral metabolite in water, juice, tea, and vinegar using ultra-high-performance liquid chromatography (UPLC). Environmentally friendly extractant was mixed with pure water to prepare a high-concentration emulsion, which was added to samples to complete the emulsification and extraction in 1 s. Afterward, an electrolyte solution was added to complete the demulsification without centrifugation. ELLME did not use dispersants compared to the familiar dispersive liquid–liquid microextraction (DLLME), thus reducing the use of toxic solvents and avoiding the effect of dispersants on the partition coefficient. The linear range was from 0.01 to 1 mg/L. The limit of detection was 0.003 mg/L. The extraction recoveries ranged from 82.4 % to 101.6 %, with relative standard deviations of 0.7–5.2 %. The ELLME method developed has the potential to serve as an alternative to DLLME.

Metabolomic Analysis and in Vitro Investigation of the Biological Properties of a By-Product Derived from Vicia faba.

By-products from plant sources are recently regarded as a valuable source of bioactive compounds. In this regard, the present study aims to assess the bioactivities of the 70 % MeOH extract obtained from Vicia faba peels and analyze its metabolomic profile. Acetylcholinesterase and carbohydrate metabolizing enzymes inhibitory activities of the plant extract were assayed using quantitative colorimetric tests. Antioxidant activity was estimated by DPPH assay, and cytotoxic activity was evaluated against normal fibroblast skin cells (1-BJ1). Ninety-one metabolites were tentatively identified using ultra-high-performance liquid chromatography (UHPLC) hyphenated with quadrupole-time-of-flight tandem mass spectrometry (QTOF-MS). Most of these compounds were described for the first time in the plant. In addition, catechin, rutin, quercitrin, and rhamnetin were isolated from the plant extract. The plant extract and the isolated compounds possessed no cytotoxic activity on (1-BJ1), while they exhibited anticholinesterase with the highest activity for 70 % MeOH extract (IC50 =120.11 mg/L), antioxidant potential with the highest activity for rutin (90.54±0.73 %), and carbohydrate metabolizing inhibitory activities with the highest activity for rutin. These discoveries imply that V. faba peels might serve as an efficient antioxidant, exhibit anticholinesterase properties, and have the potential for use in managing diabetes, all while avoiding cytotoxicity in normal cells.