Untargeted Metabolomic Study of Lung Cancer Patients after Surgery with Curative Intent

Lung cancer (LC) is a leading cause of mortality, claiming more than 1.8 million deaths per year worldwide. Surgery is one of the most effective treatments when the disease is in its early stages. The study of metabolic alterations after surgical intervention with curative intent could be used to assess the response to treatment or the detection of cancer recurrence. In this study, we have evaluated the metabolomic profile of serum samples (n = 110) from preoperative (PRE) and postoperative (POST) LC patients collected at two different time points (1 month, A; 3-6 months, B) with respect to healthy people. An untargeted metabolomic platform based on reversed phase (RP) and hydrophilic interaction chromatography (HILIC), using ultra-high performance liquid chromatography (UHPLC) and mass spectrometry (MS), was applied (MassIVE ID MSV000092213). Twenty-two altered metabolites were annotated by comparing all the different studied groups. DG(14,0/22:1), stearamide, proline, and E,e-carotene-3,3'-dione were found altered in PRE, and their levels returned to those of a baseline control group 3-6 months after surgery. Furthermore, 3-galactosyllactose levels remained altered after intervention in some patients. This study provides unique insights into the metabolic profiles of LC patients after surgery at two different time points by combining complementary analytical methods.

Characterization of chemical constituents in Huangqi Guizhi Wuwu decoction using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry

Huangqi Guizhi Wuwu decoction (HGWWD) is a classic traditional Chinese medicine prescription for the treatment of ischemic stroke, etc. However, the material basis of its efficacy remains unclear, seriously affecting drug development and clinical applications. In the present study, an ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry method was developed to separate and identify the chemical components of HGWWD. A total of 81 compounds were identified and tentatively characterized. Eight compounds were accurately identified by comparing the retention time and mass spectrometry data with those of reference substances, the remaining compounds were characterized by comparing the mass spectrometry data and reference information. Based on the results of compound attribution, 35 compounds were from Astragali Radix, six compounds were from Cinnamomi Ramulus, 23 compounds were from Paeoniae Radix Alba, eight compounds were from Zingiberis Rhizoma Recens and nine compounds were from Jujubae Fructus. The results showed that monoterpenoids, flavonoids, organic acids, triterpenes, amino acids, gingerols, alkaloids, and glycosides were the main chemical components of HGWWD. This analytical method is suitable for characterizing the chemical constituents of HGWWD, and the results provide important information for elucidating its pharmacodynamic material basis and mechanism of action.

Magnetic functionalized graphene oxide combined with ultra-high performance liquid chromatography for trace detection of succinate dehydrogenase inhibitor fungicides in food

In this study, an efficient, sensitive, and convenient magnetic solid-phase extraction method combined with ultra-high performance liquid chromatography-tandem mass spectrometry (MSPE-UHPLC-MS/MS) was developed for the simultaneous determination of 19 succinate dehydrogenase inhibitor fungicide residues in six different food matrices The synthesized tetraethylenepentamine magnetic graphene oxide nanocomposite showed the advantages of good dispersibility, large specific surface area (113.93 m2 /g) and large pore volume (0.25 cm3 /g), making it an ideal succinate dehydrogenase inhibitor pretreatment adsorbent. The MSPE-UHPLC-MS/MS method showed linearity in the range of 5.0-800.0 μg/kg, with a correlation coefficient (R2 ) > 0.99, and a limit of quantification of 5 μg/kg. The recovery of succinate dehydrogenase inhibitor fungicides was in the range of 71.2%-119.4%. The MSPE method is simple, rapid, and efficient, making it an ideal alternative to sample pretreatment in the determination of trace succinate dehydrogenase inhibitor fungicides in complex matrices.

Determination of Isoflavones in Radix puerariae from Different Origins by Ultra-High Performance Liquid Chromatography Based on Optimal Pretreatment Method

A new method for simultaneous determination of puerarin, daidzin, daidzein and genistein in Radix puerariae by ultra-high performance liquid chromatography was established. The target analytes were extracted from Radix puerariae by 70% ethylene glycol with the assistance of ultrasonication, purified by the absorption of N-propyl ethylenediamine (PSA), and separated on a Supersil ODS column (4.6 mm × 250 mm × 2.5 μm). Gradient elution in 12 min was performed with the mobile phase 0.1% formic acid(A)-acetonitrile(B). The column temperature was 25 °C and the flow rate was 1 mL/min. The detection wavelength of the four target analytes was 250 nm. The limits of detection (LODs) of puerarin, daidzin, daidzein and genistein were 0.086 mg/L, 0.020 mg/L, 0.027 mg/L and 0.037 mg/L, respectively, and limits of quantitation (LOQs) were 0.29 mg/L, 0.065 mg/L, 0.090 mg/L and 0.12 mg/L, respectively. The recovery of the four substances ranged from 90.5% to 109.6%, and the relative standard deviation (n = 6) was less than 7.7%. With the established methods, puerarin, daidzin, daidzein and genistein in Radix puerariae from 11 origins were determined. The contents of the four compounds varied with the origin and variety. It provides basic data and technical means for quality control and regulation of Radix puerariae.

Simultaneous determination of 10 first-generation histamine h1 receptor blockers in feeds by ultra-high-performance liquid chromatography triple quadrupole ion trap hybrid mass spectrometer

A method for simultaneous determination of 10 first-generation histamine H1 receptor blockers in feeds by ultra-high-performance liquid chromatography triple quadrupole mass spectrometry combined with solid phase extraction. Instrument conditions, extraction solvents, and purification methods have been optimized. Under the optimum conditions, these analytes were separated effectively at 6 min. These feeds have been extracted by acid acetonitrile and purified by mixed cation exchange solid-phase extraction. The performance of this method meets the requirements of veterinary residue detection in feeds in China. It is appropriate for the confirmatory monitoring and quantitative analysis of 105 feed samples, five kinds of histamine H1 receptor blockers have been detected in 10 samples.

Technical note: simultaneous determination of amino thiols in pig tissue by ultra-high performance liquid chromatography with fluorescence detection

Sulfur amino acid nutrition and metabolism are linked to animal disease. While validated methods for the determination of amino thiol levels in plasma or serum are available, there is a dearth of validated methods for their measurement in tissue. A robust and reproducible ultra-high performance liquid chromatography method has been validated for the simultaneous determination of concentrations of cysteine (Cys), cysteinylglycine (CysGly), homocysteine (Hcys), γ-glutamylcysteine (γ-GluCys), and glutathione (GSH) in pig tissue. Tissue was homogenized and deproteinized with trichloroacetic acid. Amino thiols in the acid-soluble fraction of the tissue homogenate were reduced with tris-(2-carboxyethyl)-phosphine hydrochloride and derivatized with 4-(aminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (ABD-F). Amino thiols were resolved under reversed-phase gradient conditions on a Waters Acquity BEH C18 column (1.7 µm, 2.1 mm × 100 mm) within 4.5 min and detected with fluorescence. The peak area ratio of analyte to 2-mercaptopropionylglycine internal standard, added to external calibration standards and samples, was used to develop linear calibration curves. Linear calibrations were performed over the range of 15-1,500 nmol/g for Cys, CysGly, Hcys, and γ-GluCys and 150-15,000 nmol/g for GSH. Linearity, lower limit of detection, lower limit of quantitation, accuracy, precision, sample stability, and carryover were evaluated. We demonstrate excellent linearity for all analytes within their respective concentration range (r2 > 0.99) and excellent recovery of amino thiols from spiked samples (mean ± SD across tissues; Cys, 100.0 ± 2.2%; CysGly, 95.4 ± 5.1%; Hcys, 96.6 ± 2.0%; γ-GluCys, 102.2 ± 2.7%; and GSH, 100.6 ± 3.3%). The intra-day and inter-day precisions did not exceed 5% and 10%, respectively. Repeated freezing and thawing of tissue homogenate did not affect measured amino thiol concentrations, ABD-labeled amino thiols were stable for 1 wk after derivatization, and there was no sample carryover across consecutive injections. We confirm the identity of each ABD-labeled amino thiol with Orbitrap mass spectrometry. Finally, we apply the method to the determination of amino thiol concentrations in liver and jejunum tissues in newly weaned pigs and show that despite elevated Cys and maintained GSH concentrations in liver, both γ-GluCys and GSH decline in jejunum of weaned pigs.

Monitoring surface contamination for thirty antineoplastic drugs: a new proposal for surface exposure levels (SELs)

BACKGROUND

Chemotherapy drugs are widely used to treat cancer, but their active compounds represent a danger for workers who could be exposed to them. However, they aren't yet included in directive CE No. 1272/2008 and the European Biosafety Network has only recommended a limit value of 100 pg/cm² for surface contamination. Thus, it is crucial to assess surface contaminations in healthcare environments. Currently, the technique of choice is surface wipe test combined with liquid chromatography tandem mass spectrometry to achieve high sensibility.

MATERIAL AND METHODS

A campaign involving Careggi University Hospital (Florence, Italy) was performed from January 2020 to December 2021, collecting 1449 wipe samples between administration units, preparation unit, and personnel gloves. From the obtained data, the 90th percentile was calculated for 30 antiblastic drugs and proposed as surface exposure levels (SELs); while from data concerning personnel glove contamination, weekly contamination was estimated.

RESULTS

In the 2-year period only 417 wipe samples were found positive (28.8%), the majority of which regard samples coming from administration unit bathrooms. The proposed SELs are almost all <100 pg/cm², except for few drugs which produce higher contamination on bathroom surfaces. Also, the estimation of pharmacy personnel's glove contamination highlighted very low results (ng/week).

CONCLUSIONS

Deeply established protocols and procedures for safe handling of ADs allow for obtaining excellent cleaning results and thus a safer work environment, however, the risk of cytostatic contaminations cannot be avoided in healthcare workplaces, and thus a harmonization of classification and labeling of chemotherapy drugs throughout the European Union should be done. Med Pr. 2022;73(5):383-96.

A simple and green LC method for the determination of ibuprofen in milk-containing simulated gastrointestinal media for monitoring the dissolution studies of three dimensional-printed formulations

A fast and green ultra high-performance LC method was developed for the determination of ibuprofen in milk-containing simulated gastrointestinal media to monitor the dissolution of three-dimensional printed formulations. To remove interfering compounds, protein precipitation using methanol as a precipitation reagent was performed. The separation of the target analyte was performed on an C18 column using a mobile phase consisting of 0.05% v/v aqueous phosphoric acid solution: methanol, 25:75% v/v. Method validation was conducted using the total error concept. The β-expectation tolerance intervals did not exceed the acceptance criteria of ± 15%, meaning that 95% of future results will be included in the defined bias limits. The relative bias ranged between ─ 1.1 to + 3.2% for all analytes, while the relative standard deviation values for repeatability and intermediate precision were less than 2.8% and 3.9%, respectively. The achieved limit of detection was 0.01 μg mL^-1 and the lower limit of quantitation was established as 2 μg mL^-1 . The proposed method was simple, and it required reduced organic solvent consumption following the requirements of Green Analytical Chemistry. The method was successfully employed for the determination of ibuprofen in real biorelevant media obtained from dissolution studies. This article is protected by copyright. All rights reserved.

Development, validation and application of multi-class methods for the analysis of food additives by liquid chromatography coupled to tandem mass spectrometry

Food additives are used in numerous food products and are characterised by various physicochemical properties. In European member states, their use in food is regulated by the European Union. This work aimed to develop an accurate and high-throughput analytical method enabling the simultaneous determination of additives from different functional classes to facilitate controls and generate occurrence data for exposure assessments. The QuEChERS principle was applied due to its ease of implementation and flexibility to adjust to various food matrices. However, very polar substances could not be extracted with sufficient recoveries. Consequently, an alternative basic methanol sample-preparation methodology was developed. After sample preparation, the obtained extracts were analysed using ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Overall, the developed methodology allowed the quantification of 27 additives from the functional classes of colours, sweeteners, preservatives, and antioxidants in various foods (e.g. beverages, dairies, processed meals). The methods were also validated in terms of selectivity, linearity, matrix effect, limit of quantification, accuracy, repeatability, and intra-laboratory reproducibility. Finally, the methods were successfully applied to eighty-four actual samples. All additives were found below authorised levels. However, irregularities were spotted in labelling.

Determination of Floral Origin Markers of Latvian Honey by Using IRMS, UHPLC-HRMS, and 1H-NMR

The economic significance of honey production is crucial; therefore, modern and efficient methods of authentication are needed. During the last decade, various data processing methods and a combination of several instrumental methods have been increasingly used in food analysis. In this study, the chemical composition of monofloral buckwheat (Fagopyrum esculentum), clover (Trifolium repens), heather (Calluna vulgaris), linden (Tilia cordata), rapeseed (Brassica napus), willow (Salix cinerea), and polyfloral honey samples of Latvian origin were investigated using several instrumental analysis methods. The data from light stable isotope ratio mass spectrometry (IRMS), ultra-high performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS), and nuclear magnetic resonance (NMR) analysis methods were used in combination with multivariate analysis to characterize honey samples originating from Latvia. Results were processed using the principal component analysis (PCA) to study the potential possibilities of evaluating the differences between honey of different floral origins. The results indicate the possibility of strong differentiation of heather and buckwheat honeys, and minor differentiation of linden honey from polyfloral honey types. The main indicators include depleted δ¹⁵N values for heather honey protein, elevated concentration levels of rutin for buckwheat honey, and qualitative presence of specific biomarkers within NMR for linden honey.

Rapid qualitative profiling and quantitative analysis of Juglandis Mandshuricae Cortex and seven flavonoids by ultra-high performance liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometry

Juglandis Mandshuricae Cortex is the bark of Juglans mandshurica Maxim., which has been used as a folk medicine plant in China and India. In this study, an ultra-high performance liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometry method was developed to clarify and quantify the chemical profiling of Juglandis Mandshuricae Cortex rapidly. A total of 113 compounds were characterized. Among them, seven flavonoids were simultaneously quantified in 15 min, including myricetin, myricetrin, taxifolin, kaempferol, quercetin, quercitrin, and naringenin. The method was validated for accuracy, precision, and the limits of detection and quantification. All calibration curves showed a good linear relationship (r > 0.9990) within test ranges. The intra- and inter-day relative standard deviations were less than 2.16%. Accuracy validation showed that the recovery was between 95.6% and 101.3% with relative standard deviation values below 2.85%. The validated method was successfully applied to determine the contents of seven flavones in Juglandis Mandshuricae Cortex from seven sources and the contents of these places were calculated respectively. This method provides a theoretical basis for further developing the medicinal value of Juglandis Mandshuricae Cortex.

Determination of multiple antibiotics in agricultural soil using a quick, easy, cheap, effective, rugged, and safe method coupled with ultra-high performance liquid chromatography-tandem mass spectrometry

In this study, we combined ultra-high performance liquid chromatography with tandem mass spectrometry to establish a quick, easy, cheap, effective, rugged, and safe method of detecting 21 target antibiotics in agricultural soil samples. Antibiotics were extracted with mixed solvents consisting of ethylenediaminetetraacetic acid disodium salt dihydrate and phosphoric acid citric acid buffer and acetonitrile which were purified with octadecylsilyl as an adsorbent and anhydrous sodium sulfate as a desiccant. This method was able to effectively extract all of the target antibiotics from agricultural soils, with recovery efficiencies ranging from 55 to 108% and limits of detection between 0.09-0.68 μg/kg. We also validated this new method for selectivity, sensitivity, and reliability of detecting multiple antibiotics in 12 samples. Considering the potential environmental and public health effects of antibiotics in agricultural soils, our new method can help analyze the degree of antibiotic contamination and provide valuable information for soil quality and risk assessment.

Highly sensitive quantification of pemetrexed in human plasma using UPLC-MS/MS to support microdosing studies

Pemetrexed is an antifolate drug approved for the treatment of non-small-cell lung cancer and mesothelioma. Assessing pemetrexed pharmacokinetics after administration of a microdose (100 μg) may facilitate drug-drug interaction and dose individualization studies with cytotoxic drugs, without causing harm to patients. Therefore, a highly sensitive bioanalytical assay is required. A reversed-phase ultra-high performance liquid chromatography method was developed to determine pemetrexed concentrations in human ethylenediaminetetraacetic acid-plasma after microdosing. [¹³ C₅ ]-Pemetrexed was used as the internal standard. The sample preparation involved solid-phase extraction from plasma. Detection was performed using MS/MS in a total run time of 9.5 min. The assay was validated over the concentration range of 0.0250-25.0 μg/L pemetrexed. The average accuracies for the assay in plasma were 96.5 and 96.5%, and the within-day and between-day precision in coefficients of variations was <8.8%. Extraction recovery was 59 ± 1 and 55 ± 5% for pemetrexed and its internal standard. Processed plasma samples were stable for 2 days in a cooled autosampler at 10°C. The assay was successfully applied in a pharmacokinetic curve, which was obtained as a part of an ongoing clinical microdosing study.

Isolation, optimized extraction, and ultra-high performance liquid chromatography with photodiode array method for quantitative analysis of chiratol in Swertia paniculata

The global natural product-based industry is growing fast with the introduction of new phytochemicals and herbal extract products from different geographical regions. Swertia paniculata is a well-known plant with medicinal properties; however, the quality control for its major phytochemical constituents from the Himalayan geographical region is nevertheless reported. Therefore, the first objective of this investigation was to characterize and optimize the extraction process while the second objective was to validate a quantitative analytical method for chiratol from S. paniculata herbal extract. The chiratol was characterized with spectral analysis. The optimum extraction condition for the highest yield of metabolite was realized in chloroform as a solvent system under ultrasonication. The ultra-high performance liquid chromatography coupled with photodiode array detection method for analytical quantification was validated for specificity, linearity, limits of detection, limits of quantification, precision, repeatability, recovery, and robustness using Eclipse Plus C18 column (100 mm × 4.6 mm × 3.5 μm id). The gradient elution of water/acetonitrile as mobile phase was used at a flow rate of 0.5 ml/min. The recovery percentage was very satisfactory with values within specification. The robustness parameters showed no substantial influence of evaluated parameters by the Youden test. The developed method was ascertained to be appropriate for the proposed purpose.

Development and Validation of QuEChERS Followed by UHPLC-ToF-MS Method for Determination of Multi-Mycotoxins in Pistachio Nuts

Pistachios are one of the types of tree nut fruits with the highest mycotoxin contamination, especially of aflatoxins, worldwide. This study developed a Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method that was followed by Ultra-High Performance Liquid Chromatography combined with Time-of-Flight Mass Spectrometry (UHPLC-ToF-MS) for the determination of mycotoxins in pistachios. Different approaches to dispersive solid phase extraction as a clean-up method for high lipid matrices were evaluated. For this, classic sorbents such as C18 (octadecyl-modified silica) and PSA (primary secondary amine), and new classes of sorbents, namely EMR-Lipid (enhanced matrix removal-lipid) and Z-Sep (modified silica gel with zirconium oxide), were used. The QuEChERS method, followed by Z-Sep d-SPE clean-up, provided the best analytical performance for aflatoxins (AFB1, AFB2, AFG1 and AFG2), ochratoxin A (OTA), zearalenone (ZEA), toxin T2 (T2) and toxin HT-2 (HT2) in pistachios. The method was validated in terms of linearity, sensitivity, repeatability, interday precision and recovery; it achieved good results according to criteria imposed by Commission Regulation (EC) no. 401/2006. The method was applied to real samples and the results show that pistachios that are available in Portuguese markets are safe from mycotoxins that are of concern to human health.

Evaluation of liver tissue extraction protocol for untargeted metabolomics analysis by ultra-high-performance liquid chromatography/tandem mass spectrometry

The aim of the untargeted metabolomics study is to obtain a global metabolome coverage from biological samples. Therefore, a comprehensive and systematic protocol for tissue metabolite extraction is highly desirable. In this study, we evaluated a comprehensive liver pretreatment strategy based on ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry to obtain more metabolites using four different protocols. These protocols included (A) methanol protein precipitation, (B) two-step extraction of dichloromethane-methanol followed by methanol-water, (C) two-step extraction of methyl tert-butyl ether-methanol followed by methanol-water, and (D) two-step extraction of isopropanol-methanol followed by methanol-water. Our results showed that protocol D was superior to the others due to more extracted features, annotated metabolites, and better reproducibility. And then, the stability and extraction sequence of protocol D were evaluated. The results showed that extraction with isopropanol-methanol followed by methanol-water was the optimum preparation sequence, which offered higher extraction efficiency, satisfactory repeatability, and acceptable stability. Furthermore, the optimal protocol was successfully applied by liver samples of rats after high-fat intervention. In summary, our protocol enabled a comprehensive and systematic evaluation of liver pretreatment to obtain more medium-polar and nonpolar metabolites and was suitable for high-throughput metabolomics analysis.

Ultra-fast liquid chromatography method coupled with ultraviolet detection to quantify dimethylsulfoxide, dimethylformamide and dimethylacetamide in short half-lives radiopharmaceuticals

Radiolabelling with short half-lives radionuclides (e.g., fluorine-18 and carbon-11) must be as efficient and as fast as possible. Nucleophilic radiofluorinations and radiomethylations are conducted in polar aprotic solvents, such as dimethylsulfoxyde (DMSO), N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMA), at high temperature. Those solvents are classified as toxic according to the ICH guidelines and must be evaluated in drug such as radiopharmaceuticals. Headspace gas chromatography is the standard method for the quantification of residual solvents but is not optimized for a rapid quantification of low vapor pressure solvents such as DMSO, DMF and DMA in radiopharmaceuticals. Direct injection gas chromatography is an interesting option without incubation step but the analysis run-time remains beyond 10 min long. In consequence, we developed a very simple ultra-high performance liquid chromatography method coupled with UV detection. Following the EMA requirements, we successfully validated a 3-min run-time analysis for quantification of three solvents in short half-lives radiopharmaceuticals. We currently use this method for the quality control of radiopharmaceuticals produced in our PET center.

Metabolomic Evaluation of Tissue-Specific Defense Responses in Tomato Plants Modulated by PGPR-Priming against Phytophthora capsici Infection

Plant growth-promoting rhizobacteria (PGPR) can stimulate disease suppression through the induction of an enhanced state of defense readiness. Here, untargeted ultra-high performance liquid chromatography–mass spectrometry (UHPLC–MS) and targeted ultra-high performance liquid chromatography coupled to triple-quadrupole mass spectrometry (UHPLC–QqQ-MS) were used to investigate metabolic reprogramming in tomato plant tissues in response to priming by Pseudomonas fluorescens N04 and Paenibacillus alvei T22 against Phytophthora capsici. Roots were treated with the two PGPR strains prior to stem inoculation with Ph. capsici. Metabolites were methanol-extracted from roots, stems and leaves at two–eight days post-inoculation. Targeted analysis by UHPLC–QqQ-MS allowed quantification of aromatic amino acids and phytohormones. For untargeted analysis, UHPLC–MS data were chemometrically processed to determine signatory biomarkers related to priming against Ph. capsici. The aromatic amino acid content was differentially reprogrammed in Ps. fluorescens and Pa. alvei primed plants responding to Ph. capsici. Furthermore, abscisic acid and methyl salicylic acid were found to be major signaling molecules in the tripartite interaction. LC–MS metabolomics analysis showed time-dependent metabolic changes in the primed-unchallenged vs. primed-challenged tissues. The annotated metabolites included phenylpropanoids, benzoic acids, glycoalkaloids, flavonoids, amino acids, organic acids, as well as oxygenated fatty acids. Tissue-specific reprogramming across diverse metabolic networks in roots, stems and leaves was also observed, which demonstrated that PGPR priming resulted in modulation of the defense response to Ph. capsici infection.

Influence of Extraction Solvent on Nontargeted Metabolomics Analysis of Enrichment Reactor Cultures Performing Enhanced Biological Phosphorus Removal (EBPR)

Metabolome profiling is becoming more commonly used in the study of complex microbial communities and microbiomes; however, to date, little information is available concerning appropriate extraction procedures. We studied the influence of different extraction solvent mixtures on untargeted metabolomics analysis of two continuous culture enrichment communities performing enhanced biological phosphate removal (EBPR), with each enrichment targeting distinct populations of polyphosphate-accumulating organisms (PAOs). We employed one non-polar solvent and up to four polar solvents for extracting metabolites from biomass. In one of the reactor microbial communities, we surveyed both intracellular and extracellular metabolites using the same set of solvents. All samples were analysed using ultra-performance liquid chromatography mass spectrometry (UPLC-MS). UPLC-MS data obtained from polar and non-polar solvents were analysed separately and evaluated using extent of repeatability, overall extraction capacity and the extent of differential abundance between physiological states. Despite both reactors demonstrating the same bioprocess phenotype, the most appropriate extraction method was biomass specific, with methanol: water (50:50 v/v) and methanol: chloroform: water (40:40:20 v/v) being chosen as the most appropriate for each of the two different bioreactors, respectively. Our approach provides new data on the influence of solvent choice on the untargeted surveys of the metabolome of PAO enriched EBPR communities and suggests that metabolome extraction methods need to be carefully tailored to the specific complex microbial community under study.

Detection and Identification of Catalpol Metabolites in the Rat Plasma, Urine and Faeces Using Ultra-high Performance Liquid Chromatography-Q Exactive Hybrid Quadrupole-orbitrap High-resolution Accurate Mass Spectrometry

BACKGROUND

Catalpol, an iridoid glycoside, is one of the richest bioactive components present in Rehmannia glutinosa. More and more metabolites of drugs have exhibited various pharmacological effects, thus providing guidance for clinical application. However, few researches have paid attention to the metabolism of catalpol.

OBJECTIVE

This study aimed to establish a rapid and effective method to identify catalpol metabolites and evaluate the biotransformation pathways of catalpol in rats.

METHODS

In this study, catalpol metabolites in rat urine, plasma and faeces were analyzed by UHPLC-Q-Exactive MS for the characterization of the metabolism of catalpol. Based on high-resolution extracted ion chromatograms (HREICs) and parallel reaction monitoring mode (PRM), metabolites of catalpol were identified by comparing the diagnostic product ions (DPIs), chromatographic retention times, neutral loss fragments (NLFs) and accurate mass measurement with those of catalpol reference standard.

RESULTS

A total of 29 catalpol metabolites were detected and identified in both negative and positive ion modes. Nine metabolic reactions, including deglycosylation, hydroxylation, dihydroxylation, hydrogenation, dehydrogenation, oxidation of methylene to ketone, glucuronidation, glycine conjugation and cysteine conjugation, were proposed.

CONCLUSION

A rapid and effective method based on UHPLC-Q-Exactive MS was developed to mine the metabolism information of catalpol. Results of metabolites and biotransformation pathways of catalpol suggested that when orally administrated, catalpol was firstly metabolized into catalpol aglycone, after which phase I and phase II reactions occurred. However, hydrophilic chromatography-mass spectrometry is still needed to further find the polar metabolites of catalpol.

Biodegradation of endocrine disrupting chemicals benzyl butyl phthalate and dimethyl phthalate by Bacillus marisflavi RR014

AIM

The objectives of the present study were to explore the benzyl butyl phthalate (BBP) and dimethyl phthalate (DMP) degradation potential of Bacillus marisflavi RR014 isolated from the tap water of public toilet and also to optimize the phthalates degradation process using response surface methodology.

METHODS AND RESULTS

The minimal salt medium was used for the biodegradation analysis of phthalates. The quantification of phthalates and their intermediate metabolites identification were done by using UHPLC and LC-MS/MS respectively. The results revealed that B. marisflavi RR014 is capable of degrading both the phthalates under varying pH, temperature and salinity conditions. The formation of phthalic acid from the breakdown of BBP and DMP (500 mg l^-1 ) in the medium was observed after 24 h. After 72 h, 61% of BBP and 98·9% of DMP in the medium was degraded as monitored by UHPLC. The identification of intermediate metabolites by LC-MS/MS revealed that hydrolysis of BBP and DMP produces phthalic acid.

CONCLUSIONS

The degradation rate of both the phthalates was increased as the parameters increased up to an optimum level. The three environmental factors (pH, temperature and salt concentration) strongly affect the rate of degradation of both the phthalates. The maximum degradation rate for both the phthalates was achieved at pH 7, temperature 35°C and salt concentration of 1% as observed from the central composite experimental design.

SIGNIFICANCE AND IMPACT OF THE STUDY

It is the first report on the phthalates biodegradation potential of B. marisflavi RR014 isolated from the tap water of public toilet. The bacterium is capable of degrading BBP and DMP under varying pH, temperature and salinity, therefore, ideal to treat the phthalate contaminated environments.

Fast and Sensitive Screening of Oxandrolone and Its Major Metabolite 17-Epi-Oxandrolone in Human Urine by UHPLC-MS/MS with On-Line SPE Sample Pretreatment

Oxandrolone, a synthetic testosterone analog, is used for the treatment of several diseases associated with weight loss. Unfortunately, oxandrolone is abused by many athletes and bodybuilders due to its strong anabolic effect. We have developed and validated a highly sensitive and rapid on-line SPE-UHPLC-MS/MS method for the determination of oxandrolone and simultaneous identification of its major metabolite 17-epi-oxandrolone in urine matrices. Enrichment of the analytes via an integrated solid-phase extraction was achieved using an Acquity UPLC BEH C18 Column. Subsequently, the chromatographic separation of the on-line preconcentrated sample fraction was achieved using an Acquity HSS T3 C18 Column. For the structural identification of these analytes, a high-resolution mass spectrometer Synapt-G2Si coupled to the Acquity M-class nano-LC system with ionKey source was used. A highly sensitive determination of oxandrolone was achieved using a tandem quadrupole mass spectrometer XEVO TQD. The method was successfully validated in the linear range of oxandrolone from 81.63 pg·mL⁻¹ (limit of quantification, LOQ) to 5000 pg·mL⁻¹ in the human urine matrix. It was applied to the analysis of real urine samples obtained from a healthy volunteer after the oral administration of one dose (10 mg) of oxandrolone. Concentration vs. time dependence was tested in the time interval of 4 h–12 days (after oral administration) to demonstrate the ability of the method to detect the renal elimination of oxandrolone from the human body. Favorable performance parameters along with successful application indicate the usefulness of the proposed method for its routine use in antidoping control labs.

Evaluation of Different Tandem MS Acquisition Modes to Support Metabolite Annotation in Human Plasma Using Ultra High-Performance Liquid Chromatography High-Resolution Mass Spectrometry for Untargeted Metabolomics

Ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS) is a powerful and essential technique for metabolite annotation in untargeted metabolomic applications. The aim of this study was to evaluate the performance of diverse tandem MS (MS/MS) acquisition modes, i.e., all ion fragmentation (AIF) and data-dependent analysis (DDA), with and without ion mobility spectrometry (IM), to annotate metabolites in human plasma. The influence of the LC separation was also evaluated by comparing the performance of MS/MS acquisition in combination with three complementary chromatographic separation modes: reversed-phase chromatography (RPLC) and hydrophilic interaction chromatography (HILIC) with either an amide (aHILIC) or a zwitterionic (zHILIC) stationary phase. RPLC conditions were first chosen to investigate all the tandem MS modes, and we found out that DDA did not provide a significant additional amount of chemical coverage and that cleaner MS/MS spectra can be obtained by performing AIF acquisitions in combination with IM. Finally, we were able to annotate 338 unique metabolites and demonstrated that zHILIC was a powerful complementary approach to both the RPLC and aHILIC chromatographic modes. Moreover, a better analytical throughput was reached for an almost negligible loss of metabolite coverage when IM-AIF and AIF using ramped instead of fixed collision energies were used.

A Fast and Reliable UHPLC-MS/MS-Based Method for Screening Selected Pharmacologically Significant Natural Plant Indole Alkaloids

Many substances of secondary plant metabolism have often attracted the attention of scientists and the public because they have certain beneficial effects on human health, although the reason for their biosynthesis in the plant remains unclear. This is also the case for alkaloids. More than 200 years have passed since the discovery of the first alkaloid (morphine), and several thousand substances of this character have been isolated since then. Most often, alkaloid-rich plants are part of folk medicine with centuries-old traditions. What is particularly important to monitor for these herbal products is the spectrum and concentrations of the present active substances, which decide whether the product has a beneficial or toxic effect on human health. In this work, we present a fast, reliable, and robust method for the extraction, preconcentration, and determination of four selected alkaloids with an indole skeleton, i.e., harmine, harmaline, yohimbine, and ajmalicine, by ultra-high performance liquid chromatography coupled with tandem mass spectrometry. The applicability of the method was demonstrated for tobacco and Tribulus terrestris plant tissue, the seeds of Peganum harmala, and extract from the bark of the African tree Pausinystalia johimbe.

A Survey of the Presence of Pharmaceutical Residues in Wastewaters. Evaluation of Their Removal using Conventional and Natural Treatment Procedures

To encourage the reutilization of treated wastewaters as an adaptation strategy to climate change it is necessary to demonstrate their quality. If this is ensured, reclaimed waters could be a valuable resource that produces very little environmental impact and risks to human health. However, wastewaters are one of the main sources of emerging pollutants that are discharged in the environment. For this, it is essential to assess the presence of these pollutants, especially pharmaceutical compounds, in treated wastewaters. Moreover, the different treatment processes must be evaluated in order to know if conventional and natural treatment technologies are efficient in the removal of these types of compounds. This is an important consideration if the treated wastewaters are used in agricultural activities. Owing to the complexity of wastewater matrixes and the low concentrations of pharmaceutical residues in these types of samples, it is necessary to use sensitive analytical methodologies. In this study, the presence of 11 pharmaceutical compounds were assessed in three different wastewater treatment plants (WWTPs) in Gran Canaria (Spain). Two of these WWTPs use conventional purification technologies and they are located in densely populated areas, while the other studied WWTP is based in constructed wetlands which purify the wastewaters of a rural area. The sampling was performed monthly for two years. A solid phase extraction (SPE) coupled to ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was applied for the analysis of the samples, and the 11 pharmaceuticals were detected in all the studied WWTPs. The concentrations were variable and ranged from ng·L^-1 in some compounds like diclofenac or carbamazepine to µg·L^-1 in common pharmaceutical compounds such as caffeine, naproxen or ibuprofen. In addition, removal efficiencies in both conventional and natural purification systems were evaluated. Similar removal efficiencies were obtained using different purifying treatments, especially for some pharmaceutical families as stimulants or anti-inflammatories. Other compounds like carbamazepine showed a recalcitrant behavior. Secondary treatments presented similar removal efficiencies in both conventional and natural wastewater treatment plants, but conventional treatments showed slightly higher elimination ratios. Regarding tertiary system, the treatment with highest removal efficiencies was reverse osmosis in comparison with microfiltration and electrodialysis reversal.

Effect of the Refining Process on Total Hydroxytyrosol, Tyrosol, and Tocopherol Contents of Olive Oil

The impact of the olive oil refining process on major antioxidant compound levels was evaluated by means of UHPLC analysis of lampante olive oils collected at different stages of the refining procedure (degumming, chemical and physical flash neutralization, bleaching, and deodorization). For this purpose, the evolution of the tocopherol fraction was investigated by means of the UHPLC-FL method, while the influence of the refining process on the total hydrolyzed phenolic content was assessed by measuring hydroxytyrosol and tyrosol levels after acid hydrolysis of the phenolic extracts. Refining was found to have a marked effect on total hydroxytyrosol and tyrosol contents, as they are completely removed in the early steps of the refining procedure. In contrast, the variation trends of tocopherols are not always clear-cut, and significant decreases in content from 7% to 16% were only revealed during refining in four out of nine samples. In addition, five of the nine refined oils showed final tocopherol concentrations higher than 200 mg/kg, the limit imposed by international standards regarding the content of such compounds in commercial olive oils. This study supports the need for a revision of the International Olive Oil Council (IOC) standard relative to the limit established for tocopherol addition to refined oils to avoid possible legal and economic trade issues.

Poultry Farms as a Potential Source of Environmental Pollution by Pharmaceuticals

Industrial poultry breeding is associated with the need to increase productivity while maintaining low meat prices. Little is known about its impact on the environment of soil pollution by pharmaceuticals. Breeders routinely use veterinary pharmaceuticals for therapeutic and preventive purposes. The aim of this work was to determine the influence of mass breeding of hens on the soil contamination with 26 pharmaceuticals and caffeine. During two seasons—winter and summer 2019—15 soil samples were collected. Liquid extraction was used to isolate analytes from samples. Extracts were analyzed using ultra-high performance liquid chromatography coupled with tandem mass spectrometry detection (UPLC-MS/MS). The results showed the seasonal changes in pharmaceutical presence in analyzed soil samples. Ten pharmaceuticals (metoclopramide, sulphanilamide, salicic acid, metoprolol, sulphamethazine, nimesulide, carbamazepine, trimethoprim, propranolol, and paracetamol) and caffeine were determined in soil samples collected in March, and five pharmaceuticals (metoclopramide, sulphanilamide, sulphamethazine, carbamazepine, sulfanilamid) in soil samples collected in July. The highest concentrations were observed for sulphanilamide, in a range from 746.57 ± 15.61 ng/g d.w to 3518.22 ± 146.05 ng/g d.w. The level of bacterial resistance to antibiotics did not differ between samples coming from intensive breeding farm surroundings and the reference area, based on antibiotic resistance of 85 random bacterial isolates.

[Simultaneous Quantitative Detection of Thirteen Common Antibiotics in Leafy Vegetables by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry]

An analytical approach was developed to simultaneously determine 13 antibiotics in sulfonamides, quinolones, and macrolides in leafy vegetables by ultra-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-MS/MS). After optimizing extracted solutions, purification methods, and eluents of antibiotics in vegetable substrates, and taking into account the influence of environmental changes and experimental conditions on the results, the optimal experimental scheme was determined. This involved ①weighing 500 mg of vegetable samples and adding 20 mL of methanol-Mcllvaine-Na₂ EDTA solution; ② conducting ultrasonic and centrifugal extraction three times; ③ Allowing rotary evaporation to 20 mL to pass a HLB solid phase extraction column; ④ Eluting the extraction column using 6 mL of methanol, upon which the eluent was dried almost completely; ⑤ Re-dissolving the eluent with a mixed solution of acetonitrile:water (volume ratio of 2:8); ⑥ Detecting by UPLC-MS/MS after centrifugation and filtering. Phase A and B of UPLC-MS/MS used an aqueous solution of 1‰ formic acid and acetonitrile, respectively to conduct gradient elution. Results showed that when the pakchoi spiked at 300 ng·g^-1, the spiked recoveries of 13 antibiotics were 38.05%-96.97%. At 150 ng·g^-1, the spiked recoveries were 34.52%-111.10%. At 50 ng·g^-1, the recoveries of standard addition were 41.75%-107.13%, and the relative deviation (RSD) values were all below 8.68%. The detection limit was 0.4-1 ng·g^-1, and the limit of quantification was 1.5-3 ng·g^-1. This demonstrated good extraction and recovery efficiency on different types of leafy vegetables, and presented a good analytical application effect. The antibiotic residues were detected in four kinds of leafy vegetables in found in markets. The total content ranged from 1.59 ng·g^-1 to 32.01 ng·g^-1, and the antibiotic content in samples was calculated by dry weight. The content of antibiotics in pakchoi was the highest, followed by Chinese cabbage, lettuce, and coriander. Among the antibiotics detected, sulfadimidine was the most abundant from the selected leafy vegetables. The content of antibiotics was very low, however the potential health risks caused by long-term consumption could not be ignored.

Occurrence of the Persistent Antimicrobial Triclosan in Microwave Pretreated and Anaerobically Digested Municipal Sludges under Various Process Conditions

Treatment of emerging contaminants, such as antimicrobials, has become a priority topic for environmental protection. As a persistent, toxic, and bioaccumulative antimicrobial, the accumulation of triclosan (TCS) in wastewater sludge is creating a potential risk to human and ecosystem health via the agricultural use of biosolids. The impact of microwave (MW) pretreatment on TCS levels in municipal sludge is unknown. This study, for the first time, evaluated how MW pretreatment (80 and 160 °C) itself and together with anaerobic digestion (AD) under various sludge retention times (SRTs: 20, 12, and 6 days) and temperatures (35 and 55 °C) can affect the levels of TCS in municipal sludge. TCS and its potential transformation products were analyzed with ultra-high-performance liquid chromatography and tandem mass spectrometry. Significantly higher TCS concentrations were detected in sludge sampled from the plant in colder compared to those in warmer temperatures. MW temperature did not have a discernible impact on TCS reduction from undigested sludge. However, AD studies indicated that compared to controls (no pretreatment), MW irradiation could make TCS more amenable to biodegradation (up to 46%), especially at the elevated pretreatment and digester temperatures. At different SRTs studied, TCS levels in the thermophilic digesters were considerably lower than that of in the mesophilic digesters.

Identification of the major metabolites of (R)-salbutamol in human urine, plasma and feces using ultra high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry

(R)-Salbutamol is a selective β2-adrenoreceptor agonist, which produces a short-acting bronchodilator effect and is widely used for the treatment of respiratory diseases in humans. Drug metabolism and identification of the metabolites play an essential role in the evaluation of the overall efficacy and safety of the drugs in clinical practices. There are few reports on the identification of major metabolites of (R)-salbutamol in humans, and the number of identified metabolites is very limited. In this research, a method of ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was developed for the discovery and identification of (R)-salbutamol and its major metabolites in human biological samples. Totally, twelve metabolites of (R)-salbutamol were found and identified and all the metabolites could be found in urine, one metabolite in plasma and two metabolites in feces. Among all the metabolites, eight metabolites have never been reported before. The results indicated that (R)-salbutamol was mainly metabolized through isomerization, oxidation, reduction, glucuronidation, and sulfation pathways in vivo. The possible metabolic pathways of (R)-salbutamol were subsequently presented in this study, which contribute to a better understanding of the metabolism of (R)-salbutamol in humans.

Deep Eutectic Solvent Micro-Functionalized Graphene Assisted Dispersive Micro Solid-Phase Extraction of Pyrethroid Insecticides in Natural Products

Deep eutectic solvent micro-functionalized graphene (DES-G) was synthesized and first applied as the adsorbent of dispersive micro solid-phase extraction (DMSPE) to extract five pyrethroid insecticides. In DMSPE, the target analytes were absorbed by DES-G and then desorbed by trace eluent, next, the treated samples were quantified via ultra-high performance liquid chromatography equipped with diode-array detection. A scanning electron microscope, transmission electron microscopy and Fourier transform infrared spectrometer were used to characterize the prepared DES-G. Furthermore, this method was verified under the selected conditions with the precision for retention times ranging from 0.43 to 0.57%, and repeatability ranged from 0.04 to 2.41% for peak areas. The developed method was successfully applied to determine pyrethroid insecticides residues in beebread, Curcuma wenyujin and Dendrobium officinale with the recoveries in the range of 80.9–114.1%.

At-Line Monitoring of the Extraction Process of Rosmarini Folium via Wet Chemical Assays, UHPLC Analysis, and Newly Developed Near-Infrared Spectroscopic Analysis Methods

The present study demonstrates the applicability of at-line monitoring of the extraction process of Rosmarinus officinalis L. leaves (Rosmarini folium) and the development of near-infrared (NIR) spectroscopic analysis methods. Therefore, whole dried Rosmarini folium samples were extracted by maceration with 70% (v/v) ethanol. For the experimental design three different specimen-taking plans were chosen. At first, monitoring was carried out using three common analytical methods: (a) total hydroxycinnamic derivatives according to the European Pharmacopoeia, (b) total phenolic content according to Folin–Ciocalteu, and (c) rosmarinic acid content measured by UHPLC-UV analysis. Precision validation of the wet chemical assays revealed a repeatability of (a) 0.12% relative standard deviation (RSD), (b) 1.1% RSD, and (c) 0.28% RSD, as well as an intermediate precision of (a) 4.1% RSD, (b) 1.3% RSD, and (c) 0.55% RSD. The collected extracts were analyzed with a NIR spectrometer using a temperature-controlled liquid attachment. Samples were measured in transmission mode with an optical path length of 1 mm. The combination of the recorded spectra and the previously obtained analytical reference values in conjunction with multivariate data analysis enabled the successful establishment of partial least squares regression (PLSR) models. Coefficients of determination (R²) were: (a) 0.94, (b) 0.96, and (c) 0.93 (obtained by test-set validation). Since Pearson correlation analysis revealed that the reference analyses correlated with each other just one of the PSLR models is required. Therefore, it is suggested that PLSR model (b) be used for monitoring the extraction process of Rosmarini folium. The application of NIR spectroscopy provides a fast and non-invasive alternative analysis method, which can subsequently be implemented for on- or in-line process control.

Determination of GL-V9, a derivative of wogonin, in rat plasma by UPLC-MS/MS and its application to a pharmacokinetic study after oral and pulmonary administration

GL-V9, a derivative of wogonin, shows much more potent anticancer properties than wogonin. In this study, a selective, sensitive and rapid ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the determination of GL-V9 in rat plasma. Plasma samples were processed using methanol to precipitate protein. Chromatographic separation of analytes was achieved on a C₁₈ column using gradient elution within 4.5 min. The mobile phase consisted of acetonitrile and water including 0.1% (v/v) formic acid and 5 mm ammonium acetate. GL-V9 and caffeine (internal standard) were monitored by positive electrospray triple quadrupole mass spectrometer and quantified using multiple reaction monitoring (MRM) mode with the transitions of m/z 410.20 → 126.10 (GL-V9) and 195.10 → 138.00 (IS: caffeine), respectively. Good linearity was obtained over the range of 2-1000 ng/mL (R²  > 0.99) and the extraction recovery was 101.91 ± 11.34%. The intra- and inter-day precision variations were small (RSD 1.35-6.96%) and the relative error (RE) of accuracy was -7.35-6.27%. The established and validated UPLC-MS/MS method was successfully applied to study the pharmacokinetic behavior of GL-V9 after administration through different delivery routes. The results demonstrated that pulmonary delivery exhibited a greater advantage in terms of improving bioavailability compared with oral administration.

The Type 2 Diabetes Susceptibility PROX1 Gene Variants Are Associated with Postprandial Plasma Metabolites Profile in Non-Diabetic Men

The prospero homeobox 1 (PROX1) gene may show pleiotropic effects on metabolism. We evaluated postprandial metabolic alterations dependently on the rs340874 genotypes, and 28 non-diabetic men were divided into two groups: high-risk (HR)-genotype (CC-genotype carriers, n = 12, 35.3 ± 9.5 years old) and low-risk (LR)-genotype (allele T carriers, n = 16, 36.3 ± 7.0 years old). Subjects participated in two meal-challenge-tests with high-carbohydrate (HC, carbohydrates 89%) and normo-carbohydrate (NC, carbohydrates 45%) meal intake. Fasting and 30, 60, 120, and 180 min after meal intake plasma samples were fingerprinted by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). In HR-genotype men, the area under the curve (AUC) of acetylcarnitine levels was higher after the HC-meal [+92%, variable importance in the projection (VIP) = 2.88] and the NC-meal (+55%, VIP = 2.00) intake. After the NC-meal, the HR-risk genotype carriers presented lower AUCs of oxidized fatty acids (−81–66%, VIP = 1.43–3.16) and higher linoleic acid (+80%, VIP = 2.29), while after the HC-meal, they presented lower AUCs of ornithine (−45%, VIP = 1.83), sphingosine (−48%, VIP = 2.78), linoleamide (−45%, VIP = 1.51), and several lysophospholipids (−40–56%, VIP = 1.72–2.16). Moreover, lower AUC (−59%, VIP = 2.43) of taurocholate after the HC-meal and higher (+70%, VIP = 1.42) glycodeoxycholate levels after the NC-meal were observed. Our results revealed differences in postprandial metabolites from inflammatory and oxidative stress pathways, bile acids signaling, and lipid metabolism in PROX1 HR-genotype men. Further investigations of diet–genes interactions by which PROX1 may promote T2DM development are needed.

Chemical Fingerprinting and Quantification of Chinese Cinnamomi Cortex by Ultra High Performance Liquid Chromatography Coupled with Chemometrics Methods

To rapidly clarify and quantify the chemical profiling of Cinnamomi cortex a reliable and feasible strategy of chromatographic fingerprinting with a suite of chemometrics methods was developed and validated by ultra-high performance liquid chromatography coupled with diode array detection. Furthermore, to identify more meaningful chemical markers, the chemometrics methods including hierarchical cluster analysis (HCA), principal component analysis (PCA) and similarity, which all generate quality evaluations and correlation classifications of Cinnamomi cortex, were used to improve the Cinnamomi cortex quality control standards. A total of 12 characteristic peaks were confirmed, seven of which were identified by comparing their retention times, UV and MS spectra with authentic compounds. Moreover, 11 analytes were accurately determined, as a complementary quantification method of chromatographic fingerprinting. For quantitative analyses, selective detection was performed at 254, 280 and 340 nm. The tested samples were separated and determined using UPLC and a series of methodologies including linearity, precision, accuracy, limit of detection and quantification and extraction recoveries were validated. Meanwhile the method bias for all the analytes did not exceed 5%. A total of 42 samples were acquired in China and analyzed. The results demonstrated that chromatographic fingerprinting in combination with chemometrics methods provides a promising and practical method to more effectively and comprehensively control the quality of Cinnamomi cortex from various sources, which would be a useful reference for the development and further study of Cinnamomi cortex and related formulations.

Multistep Optimization of β-Glucosidase Extraction from Germinated Soybeans (Glycine max L. Merril) and Recovery of Isoflavone Aglycones

Epicotyls from germinated soybeans (EGS) have great potential as sources of endogenous β-glucosidase. Furthermore, this enzyme may improve the conversion of isoflavones into their corresponding aglycones. β-Glucosidase may also increase the release of aglycones from the cell wall of the plant materials. Therefore, the aim of this work was to optimize both the extraction of β-glucosidase from EGS and to further examine its application in defatted soybean cotyledon to improve the recovery of aglycones, which were evaluated by ultra-high performance liquid chromatography (UHPLC). A multistep optimization was carried out and the effects of temperature and pH were investigated by applying a central composite design. The linear effect of pH and the quadratic effect of pH and temperature were significant for the extraction of β-glucosidase and recovery aglycones, respectively. Optimum extraction of β-glucosidase from EGS occurred at 30 °C and pH 5.0. Furthermore, the maximum recovery of aglycones (98.7%), which occurred at 35 °C and pH 7.0⁻7.6 during 144 h of germination, increased 8.5 times with respect to the lowest concentration. The higher bioaccessibility of aglycones when compared with their conjugated counterparts is well substantiated. Therefore, the data provided in this contribution may be useful for enhancing the benefits of soybean, their products, and/or their processing by-products.

Quantification of Glutamate and Aspartate by Ultra-High Performance Liquid Chromatography

Glutamic and aspartic acid fulfil numerous functions in organisms. They are proteinogenic amino acids, they function as neurotransmitters, and glutamic acid links the citrate cycle with amino acid metabolism. In addition, glutamic acid is a precursor for many bioactive molecules like γ-aminobutyric acid (GABA). In tomatoes, glutamic acid accumulates in ripening fruits. Here we present a simple and rapid method for quantification of glutamate and aspartate in tomatoes. A cleared extract is prepared and 2-aminoadipic acid added as internal standard. Subsequently, the amino acids are derivatised with 2,4-dinitro-1-fluorobenzene under alkaline conditions. The derivatives are separated by ultra-high performance liquid chromatography using a phenyl-hexyl column and 50 mM N-methylmorpholine/acetate buffer pH 7.4 containing 12% acetonitrile as eluent and detected by UV absorption at 363 nm. The whole analysis time including separation and column equilibration takes less than 2.8 min with a flow rate of 1 mL/min and less than 1.6 min with a flow rate of 2 mL/min, making this method suitable for high-throughput applications. The method shows excellent reproducibility with intra- and inter-day SDs of approximately 4% for both aspartic and glutamic acid. Using this method we show that the glutamate/aspartate ratio changes significantly during fruit ripening.

Syringe cleanup with UHPLC-MS/MS for nitroimidazoles and steroids detection in manure-based fertilizers

A syringe-dispersive solid-phase extraction method was developed for the determination of seven nitroimidazoles and nine steroids in manure-based fertilizers by ultra-high performance liquid chromatography with tandem mass spectrometry. Methanol and acetonitrile were used to extract the sample, and mixed dispersive sorbents dispersed in the syringe were used for purification. The extract was separated with an HSS-T3 column and detected in positive or negative multiple reaction monitoring mode. Under the optimal conditions, the recoveries of the 16 compounds ranged from 70.3 to 112.3% at the four spiked levels (3, 10, 20, and 50 μg/kg) and the relative standard deviations ranged from 1.0 to 12.4%. The limits of detection and quantification were 0.22-0.86 and 0.73-2.87 μg/kg, respectively. This method is simple, fast, and reliable, and can be used to simultaneously screen and determine nitroimidazoles and steroids in manure-based fertilizers.

Development and validation of an analytical method for multiresidue determination of pesticides in lettuce using QuEChERS-UHPLC-MS/MS

A new analytical method for multiresidue determination of 16 multiclass pesticides in lettuce was developed using ultra-high performance liquid chromatography with tandem mass spectrometry with a triple quadrupole mass analyzer and positive mode electrospray ionization, using a previously optimized quick, easy, cheap, effective, rugged, and safe method for sample preparation. Validation studies, according to document SANTE/11945/2015, demonstrated that the developed method is selective, accurate, and precise, providing recoveries of 70-120%, relative standard deviations ≤20% and quantification limits from 3 μg/kg. The method was compared with one based on high-performance liquid chromatography with tandem mass spectrometry, in terms of chromatographic performance, detectability and matrix effect for five varieties of lettuce. The new method provided a reduction in the time for the chromatographic analysis of 50%, from 30 to 15 min, using a lower mobile phase flow rate (0.147 mL/min), which reduced the consumption of mobile phase by 25%, and injection of smaller amounts of sample (1.7 μL). Lower limits of quantification were obtained for almost all pesticides studied for green-leaf lettuce. However, in relation to the matrix effect, four of the five types of lettuce studied presented higher matrix effects.

Rapid characterization of chemical constituents and metabolites of Qi-Jing-Sheng-Bai granule by using UHPLC-Q-TOF-MS

Qi-Jing-Sheng-Bai granule is an effective traditional Chinese medicine formula that has been widely used for the treatment of leukopenia post radiotherapy or chemotherapy. However, its chemical constituents were still unclear, which hindered interpreting bioactive constituents and studying integrative mechanisms. In this study, we developed a three-step strategy to characterize the chemical constituents and metabolites of Qi-Jing-Sheng-Bai by using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. As a result, a total of 143 compounds, including 56 flavonoids, 51 saponins, and 36 other compounds, of which contained six pairs of isomers, were tentatively identified and characterized via reference standards and by comparing mass spectrometry data with literature. After oral administration of 15 g/kg Qi-Jing-Sheng-Bai, a number of 42 compounds including 24 prototype compounds and 18 metabolites have been detected in the serum of rats. This work serves as the first reference for Qi-Jing-Sheng-Bai chemical components and metabolites. Moreover, it provided a rapid and valid analytical strategy for characterization of the chemical compounds and metabolites of traditional Chinese medicine formula.

Quantitative Analysis of Ingenol in Euphorbia species via Validated Isotope Dilution Ultra-high Performance Liquid Chromatography Tandem Mass Spectrometry

INTRODUCTION

Various species of the Euphorbia genus contain diterpene ingenol and ingenol mebutate (ingenol-3-angelate), a substance found in the sap of the plant Euphorbia peplus and an inducer of cell death. A gel formulation of the drug has been approved by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for the topical treatment of actinic keratosis.

OBJECTIVE

To develop a rapid and reliable method for quantification of ingenol in various plant extracts.

METHODOLOGY

Methanolic extracts of 38 species of the Euphorbia genus were analysed via ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) after methanolysis and solid-phase extraction (SPE) purification. The ¹⁸ O-labelled ingenol analogue was prepared and used as an internal standard for ingenol content determination and method validation.

RESULTS

The highest ingenol concentration (547 mg/kg of dry weight) was found in the lower leafless stems of E. myrsinites. The screening confirms a substantial amount of ingenol in species studied previously and furthermore, reveals some new promising candidates.

CONCLUSION

The newly established UHPLC-MS/MS method shows to be an appropriate tool for screening of the Euphorbia genus for ingenol content and allows selection of species suitable for raw material production and/or in vitro culture initiation. Copyright © 2017 John Wiley & Sons, Ltd.

Simultaneous Determination of Twenty-Five Compounds in Rat Plasma Using Ultra-High Performance Liquid Chromatography-Polarity Switching Tandem Mass Spectrometry and Its Application to a Pharmacokinetic Study

An attempt was made to characterize the pharmacokinetic profiles of Qishen Keli (QSKL) that has been widely proved to be effective in clinical practice. A method using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) for the simultaneous determination of 25 analytes in rat plasma was developed and validated. Satisfactory chromatographic separation was achieved on an ACQUITY UPLC HSS T3 column with gradient elution using mobile phase consisting of 0.02% aqueous formic acid (A) and acetonitrile fortified with 0.02% formic acid (B), and analyte detection was carried out using polarity-switching multiple reaction monitoring mode. Method validation assays in terms of selectivity, linearity, inter- and intra-day variations, matrix effect, and recovery demonstrated the newly developed method to be specific, sensitive, accurate, and precise. Following the oral administration of QSKL at a single dose, the qualified method was successfully applied for pharmacokinetic investigations in sham and model rats. Mild differences occurred for the pharmacokinetic patterns of most components between those two groups, whereas significant differences were observed for glycyrrhizic acid and glycyrrhetic acid. The obtained findings could provide meaningful information for the clarification of the effective material basis of QSKL.

Pharmacokinetics and metabolism of olerciamide A from Portulaca oleracea L. in rats by UHPLC-UV and UHPLC-ESI-Q-TOF/MS

The aim of this study was to elucidate the pharmacokinetics of olerciamide A in rats after oral and intravenous administration of Portulaca oleracea L. extract by a simple and rapid ultra high-performance liquid chromatography method with bergapten as internal standard. The pharmacokinetic results indicated that olerciamide A was rapidly distributed with a time to peak concentration of 30 min after oral administration and presented a low oral absolute bioavailability of 4.57%. The metabolism of olerciamide A in rats was also investigated using ultra-high-performance liquid chromatography electrospray coupled with quadrupole-time of flight mass spectrometry to elucidate the reason for the low absolute bioavailability of olerciamide A and seven metabolites of oleraciamide A were found in rat plasma and urine.

Comparative analysis of 15 chemical constituents in Scutellaria baicalensis stem-leaf from different regions in China by ultra-high performance liquid chromatography with triple quadrupole tandem mass spectrometry

Scutellaria baicalensis is a traditional Chinese herbal medicine containing multiple components, which has been extensively used in clinics to treat epidemic febrile disease and hyperactivity cough. To get a deeper understanding about Scutellaria baicalensis stem-leaf resources, we analyzed 15 chemical constituents in 35 batches of Scutellaria baicalensis stem-leaf from eight regions in China. A rapid, simple, and sensitive method using ultra-high performance liquid chromatography coupled with triple quadrupole electrospray tandem mass spectrometry has been developed for the first time to simultaneously determine 15 chemical constituents (including phenolic acids and flavonoids) in Scutellaria baicalensis stem-leaf. Sufficient separation of 15 target constituents was achieved on a Waters Acquity UPLC BEH C₁₈ (2.1 mm × 100 mm, 1.7 μm) column within 14 min under the optimized chromatographic conditions. The established method was validated and showed good linearity, precision, repeatability, stability, and recovery and was successfully applied for the simultaneous determination of the 15 chemical constituents in these samples. Hierarchical clustering analysis and principal components analysis were performed to estimate and classify these samples based on the contents of the 15 chemical constituents. This study provided theoretical basis and scientific evidence for the development and utilization of Scutellaria baicalensis stem-leaf resources.

Comparative analysis of main bio-active components in the herb pair Danshen-Honghua and its single herbs by ultra-high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry

A sensitive, reliable, and powerful ultra-high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry method was developed for simultaneous quantification of the 15 main bio-active components including phenolic acids and flavonoids within 13 min for the first time. The proposed method was first reported and validated by good linearity (r²  > 0.9975), limit of detection (1.12-7.01 ng/mL), limit of quantification (3.73-23.37 ng/mL), intra- and inter-day precisions (RSD ≤ 1.92%, RSD ≤ 2.45%), stability (RSD ≤ 5.63%), repeatability (RSD ≤ 4.34%), recovery (96.84-102.12%), and matrix effects (0.92-1.02). The established analytical methodology was successfully applied to comparative analysis of main bio-active components in the herb pair Danshen-Honghua and its single herbs. Compared to the single herb, the content of most flavonoid glycosides was remarkably increased in their herb pair, and main phenolic acids were decreased, conversely. The content changes of the main components in the herb pair supported the synergistic effects on promoting blood circulation and removing blood stasis. The results provide a scientific basis and reference for the quality control of Danshen-Honghua herb pair and the drug interactions based on variation of bio-active components in herb pairs.

Response Surface Optimized Infrared-Assisted Extraction and UHPLC Determination of Flavonoid Types from Flos Sophorae

Single-factor experiment and Box-Behnken design were applied to optimize the infrared-assisted extraction (IRAE) of rutin, quercetin, kaempferol, and isorhamnetin from Flos sophorae. Four factors (extract solvent, solid-liquid ration, extraction time, infrared power) affecting the extraction yield of flavonoids were studied. Under optimized conditions the extraction yield was 33.199 ± 0.24 mg/g, which substantially improved, compared with heating reflux extraction (HRE) and ultrasonic-assisted extraction (UAE), while extraction time was only 9 min. The eluents were rich in 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azobis (2-methyl-propionamidine) dihydrochloride radical scavenging potential (IC₅₀ of DPPH: 53.44 ± 0.01 μg/mL, oxygen radical absorbance capacity (ORAC): 3785.83 ± 52 μmol/g) than the extracts obtained by HRE and UAE. In addition, an ultra-high performance liquid chromatography method was optimized for the identification and quantification of the tested flavonoids, and the method was validated based on its correlation coefficient (r), reproducibility (RSD, n = 5), and recovery values, which were 0.9994–0.9998, 0.74–1.83%, and 97.78–102.94%, respectively. These results confirmed that high extraction yield of flavonoids results in stronger antioxidant values and response surface methodology optimization of IRAE is a promising alternative to traditional extraction techniques for flavonoids from medicinal plants.

Evaluation of a new modified QuEChERS method for the monitoring of carbamate residues in high-fat cheeses by using UHPLC-MS/MS

A simple and efficient method for the determination of 28 carbamates in high-fat cheeses is proposed. The methodology is based on a modified quick, easy, cheap, effective, rugged, and safe procedure as sample treatment using a new sorbent (Z-Sep⁺ ) followed by ultra-high performance liquid chromatography with tandem mass spectrometry determination. The method has been validated in different kinds of cheese (Gorgonzola, Roquefort, and Camembert), achieving recoveries of 70-115%, relative standard deviations lower than 13% and limits of quantification lower than 5.4 μg/kg, below the maximum residue levels tolerated for these compounds by the European legislation. The matrix effect was lower than ±30% for all the studied pesticides. The combination of ultra-high performance liquid chromatography and tandem mass spectrometry with this modified quick, easy, cheap, effective, rugged, and safe procedure using Z-Sep⁺ allowed a high sample throughput and an efficient cleaning of extracts for the control of these residues in cheeses with a high fat content.

Extracts

INTRODUCTION

The quality of herbs is directly related to the presence of polyphenolic antioxidants. This is the first report on the quantification of individual polyphenolic constituents of Erigeron acris L.

OBJECTIVE

To develop a new method using ultra-high performance liquid chromatography with photodiode array and chemiluminescence (UHPLC-PDA-CL) detection for the separation and determination of polyphenols in Erigeron acris extracts.

METHODOLOGY

The methanolic extracts from leaves and inflorescences of Erigeron acris were prepared by ultrasound assisted extraction. The chromatographic separation was performed on C18 column packed with 1.7-μm particles. The post-column CL detection was based on the enhancing effect of polyphenols on the CL generated in manganese(IV)-hexametaphosphate-formaldehyde system.

RESULTS

The UHPLC method allowed to separate polyphenols in a short running time (13 min), which was three times shorter compared with traditional HPLC. The CL detection was characterised by 6-48 times higher sensitivity and up to three times lower detection limits compared to PDA detection. Qualitative and quantitative differences were observed in polyphenolic composition of Erigeron acris extracts. The main components of leaves were scutellarin and chlorogenic acid, whereas in inflorescences quercetin 3-O-glucoside was predominant.

CONCLUSION

Coupling of UHPLC with CL detection has been developed for the first time. This advanced chromatographic technique coupled with sensitive CL detection is a powerful approach for the investigation of polyphenolic profiles in natural products. The shorter analysis time and diminished waste generation makes the UHPLC method more environmentally friendly and more cost-effective in comparison with conventional HPLC. Copyright © 2016 John Wiley & Sons, Ltd.

Quantification of Temozolomide in Nonhuman Primate Fluids by Isocratic Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry to Study Brain Tissue Penetration Following Intranasal or Intravenous Delivery

A sensitive and selective ultra-high performance liquid chromatography-tandem mass spectrometric method was developed for the quantification of temozolomide (TMZ) in nonhuman primate (NHP) plasma, cerebrospinal fluid (CSF), and brain extracellular fluid (ECF) following microdialysis. Ethyl acetate was used to extract the plasma and CSF samples, using theophylline as the internal standard (IS). ECF samples were diluted with acetonitrile prior to analysis. TMZ was separated on a Waters UPLC® BEH C18 column with an isocratic mobile phase of ammonium acetate (10 mM)-0.1% formic acid/acetonitrile (30:70, v/v) in a positive-ion multi pie reaction monitoring mode (m/z 195.5 →137.6 for TMZ; m/z 181.5→124.2 for IS). The retention time of TMZ and theophylline was 0.45 min with a total run time of 2.5 min. The method was validated over the range from 5-2000 ng/mL in NHP plasma, CSF, and ECF with respect to linearity, accuracy, precision, selectivity, and stability. This method was successfully applied toward the measurement of pharmacokinetic samples following various routes of drug administration.

Comparative Evaluation of Different Extraction Techniques and Solvents for the Assay of Phytochemicals and Antioxidant Activity of Hashemi Rice Bran

Secondary metabolite contents (total phenolic, flavonoid, tocopherol, and tocotrienol) and antioxidant activities of Hashemi rice bran extracts obtained by ultrasound-assisted and traditional solvent (ethanol and 50:50 (v/v) ethanol-water) extraction techniques were compared. Phenolic and, flavonoid compounds were identified using ultra-high performance liquid chromatography and method validation was performed. Significant differences (p < 0.05) were observed among the different extraction techniques upon comparison of phytochemical contents and antioxidant activities. The extracts obtained using the ethanol-water (50:50 v/v) ultrasonic technique showed the highest amounts of total phenolics (288.40 mg/100 g dry material (DM)), total flavonoids (156.20 mg/100 g DM), and total tocotrienols (56.23 mg/100 g DM), and the highest antioxidant activity (84.21% 1,1-diphenyl-2-picrylhydrazyl (DPPH), 65.27% β-carotene-linoleic bleaching and 82.20% nitric oxide scavenging activity). Secondary metabolite contents and antioxidant activities of the rice bran extracts varied depending of the extraction method used, and according to their effectiveness, these were organized in a decreasing order as follows: ethanol-water (50:50 v/v) ultrasonic, ethanol-water (50:50 v/v) maceration, ethanol ultrasonic and ethanol maceration methods. Ferulic, gallic and chlorogenic acids were the most abundant phenolic compounds in rice bran extracts. The phytochemical constituents of Hashemi rice bran and its antioxidant properties provides insights into its potential application to promote health.