Search

Triptorelin and leuprorelin are synthetic gonadotrophin-releasing hormones (GnRH) that are on the World Anti-Doping Agency (WADA) list of prohibited substances. To investigate the possible in vivo metabolites of triptorelin and leuprorelin in humans compared to previously reported in vitro metabolites, excreted urine from five patients treated with either triptorelin or leuprorelin was analyzed by liquid chromatography coupled with ion trap/time-of-flight mass spectrometry (LC/MS-IT-TOF). The addition of dimethyl sulfoxide (DMSO) to the mobile phase was found to enhance the detection sensitivity of certain GnRH analogs. The method was validated, and the limit of detection (LOD) was found at 0.02−0.08 ng/mL. Using this method, a novel new metabolite of triptorelin was discovered in the urine of all subjects up to 1 month after triptorelin administration, but it was not observed in the urine of subjects before drug administration. The limit of detection was estimated to be 0.05 ng/mL. The structure of the metabolite, triptorelin (5-10), is proposed from bottom-up mass spectrometry analysis. The discovery of in vivo triptorelin (5-10) can possibly be used as supporting evidence of triptorelin misuse in athletes. [ABSTRACT FROM AUTHOR]

Resveratrol has anti-inflammatory, anti-cancer, and anti-aging pharmacological activities. There is currently a gap in academic research regarding the uptake, transport, and reduction of H2O2-induced oxidative damage of resveratrol in the Caco-2 cell model. This study investigated the role of resveratrol in the uptake, transport, and alleviation of H2O2-induced oxidative damage in Caco-2 cells. In the Caco-2 cell transport model, it was observed that the uptake and transport of resveratrol (10, 20, 40, and 80 μM) were time dependent and concentration dependent. Different temperatures (37 °C vs. 4 °C) could significantly affect the uptake and transportation of resveratrol. The apical to basolateral transport of resveratrol was markedly reduced by STF-31, a GLUT1 inhibitor, and siRNA intervention. Furthermore, resveratrol pretreatment (80 μM) improves the viability of Caco-2 cells induced by H2O2. In a cellular metabolite analysis combined with ultra-high performance liquid chromatography-tandem mass spectrometry, 21 metabolites were identified as differentials. These differential metabolites belong to the urea cycle, arginine and proline metabolism, glycine and serine metabolism, ammonia recycling, aspartate metabolism, glutathione metabolism, and other metabolic pathways. The transport, uptake, and metabolism of resveratrol suggest that oral resveratrol could prevent intestinal diseases caused by oxidative stress. [ABSTRACT FROM AUTHOR]

β-carbolines (harman and norharman) are potentially mutagenic and have been reported in some vegetable oils. Sesame seed oil is obtained from roasted sesame seeds. During sesame oil processing, roasting is the key procedure to aroma enhancement, in which β-carbolines are produced. Pressed sesame seed oils cover most market share, while leaching solvents are used to extract oils from the pressed sesame cake to improve the utilization of the raw materials. β-carbolines are nonpolar heterocyclic aromatic amines with good solubility in leaching solvents (n-hexane); therefore, the β-carbolines in sesame cake migrated to the leaching sesame seed oil. The refining procedures are indispensable for leaching sesame seed oil, in which some small molecules can be reduced. Thus, the critical aim is to evaluate the changes in β-carboline content during the refining of leaching sesame seed oil and the key process steps for the removal of β-carbolines. In this work, the levels of β-carbolines (harman and norharman) in sesame seed oil during chemical refining processes (degumming, deacidification, bleaching and deodorization) have been determined using solid phase extraction and high performance liquid chromatography-mass spectrometry (LC-MS). The results indicated that in the entire refining process, the levels of total β-carbolines greatly decreased, and the adsorption decolorization was the most effective process in reducing β-carbolines, which might be related to the adsorbent used in the decolorization process. In addition, the effects of adsorbent type, adsorbent dosage and blended adsorbent on β-carbolines in sesame seed oil during the decolorization process were investigated. It was concluded that oil refining can not only improve the quality of sesame seed oil, but also reduce most of the harmful β-carbolines. [ABSTRACT FROM AUTHOR]

The lichen Cetraria islandica (L.) Ach. has been used in traditional and modern medicines for its many biological properties such as immunological, immunomodulating, antioxidant, antimicrobial, and anti-inflammatory activities. This species is gaining popularity in the market, with interest from many industries for selling as medicines, dietary supplements, and daily herbal drinks. This study profiled the morpho-anatomical features by light, fluorescence, and scanning electron microscopy; conducted an elemental analysis using energy-dispersive X-ray spectroscopy; and phytochemical analysis was performed using high-resolution mass spectrometry combined with a liquid chromatography system (LC-DAD-QToF) of C. islandica. In total, 37 compounds were identified and characterized based on comparisons with the literature data, retention times, and their mass fragmentation mechanism/s. The identified compounds were classified under five different classes, i.e., depsidones, depsides, dibenzofurans, aliphatic acids, and others that contain simple organic acids in majority. Two major compounds (fumaroprotocetraric acid and cetraric acid) were identified in the aqueous ethanolic and ethanolic extracts of C. islandica lichen. This detailed morpho-anatomical, EDS spectroscopy, and the developed LC-DAD-QToF approach for C. islandica will be important for correct species identification and can serve as a useful tool for taxonomical validation and chemical characterization. Additionally, chemical study of the extract of C. islandica led to isolation and structural elucidation of nine compounds, namely cetraric acid (1), 9′-(O-methyl)protocetraric acid (2), usnic acid (3), ergosterol peroxide (4), oleic acid (5), palmitic acid (6), stearic acid (7), sucrose (8), and arabinitol (9). [ABSTRACT FROM AUTHOR]

Plant parasitic nematodes (PPNs) are highly destructive and difficult to control, while conventional chemical nematicides are highly toxic and cause serious environmental pollution. Additionally, resistance to existing pesticides is becoming increasingly common. Biological control is the most promising method for the controlling of PPNs. Therefore, the screening of nematicidal microbial resources and the identification of natural products are of great significance and urgency for the environmentally friendly control of PPNs. In this study, the DT10 strain was isolated from wild moss samples and identified as Streptomyces sp. by morphological and molecular analysis. Using Caenorhabditis elegans as a model, the extract of DT10 was screened for nematicidal activity, which elicited 100% lethality. The active compound was isolated from the extracts of strain DT10 using silica gel column chromatography and semipreparative high-performance liquid chromatography (HPLC). The compound was identified as spectinabilin (chemical formula C28H31O6N) using liquid chromatography mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR). Spectinabilin exhibited a good nematicidal activity on C. elegans L1 worms, with a half-maximal inhibitory concentration (IC50) of 2.948 μg/mL at 24 h. The locomotive ability of C. elegans L4 worms was significantly reduced when treated with 40 μg/mL spectinabilin. Further analysis of spectinabilin against known nematicidal drug target genes in C. elegans showed that it acts via target(s) different from those of some currently used nematicidal drugs such as avermectin and phosphine thiazole. This is the first report on the nematicidal activity of spectinabilin on C. elegans and the southern root-knot nematode Meloidogyne incognita. These findings may pave the way for further research and application of spectinabilin as a potential biological nematicide. [ABSTRACT FROM AUTHOR]

Soil can be contaminated by pesticide residues through agricultural practices, by direct application or through spray-drift in cultivations. The dissipation of those chemicals in the soil may pose risks to the environment and human health. A simple and sensitive multi-residue analytical method was optimized and validated for the simultaneous determination of 311 active substances of pesticides in agricultural soils. The method involves sample preparation with QuEChERS-based extraction, and determination of the analytes with a combination of GC-MS/MS and LC-MS/MS techniques. Calibration plots were linear for both detectors over the range of five concentration levels, using matrix-matched calibration standards. The obtained recoveries from fortified-soil samples ranged from 70 to 119% and from 72.6 to 119% for GC-MS/MS and LC-MS/MS, respectively, while precision values were <20% in all cases. As regards the matrix effect (ME), signal suppression was observed in the liquid chromatography (LC)-amenable compounds, which was further estimated to be negligible. The gas chromatography (GC)-amenable compounds showed enhancement in the chromatographic response estimated as medium or strong ME. The calibrated limit of quantification (LOQ) value was 0.01 μg g−1 dry weight for most of the analytes, while the corresponding calculated limit of determination (LOD) value was 0.003 μg g−1 d.w. The proposed method was subsequently applied to agricultural soils from Greece, and positive determinations were obtained, among which were non-authorized compounds. The results indicate that the developed multi-residue method is fit for the purpose of analyzing low levels of pesticides in soil, according to EU requirements. [ABSTRACT FROM AUTHOR]

Levodopa (L-DOPA) treatment, combined with the administration of dopa-decarboxylase inhibitors (DDCIs), is still the most effective symptomatic treatment of Parkinson's disease (PD). Although its efficacy in the early stage of the disease has been confirmed, its complex pharmacokinetics (PK) increases the variability of the intra-individual motor response, thus amplifying the risk of motor/non-motor fluctuations and dyskinesia. Moreover, it has been demonstrated that L-DOPA PK is strongly influenced by several clinical, therapeutic, and lifestyle variables (e.g., dietary proteins). L-DOPA therapeutic monitoring is therefore crucial to provide personalized therapy, hence improving drug efficacy and safety. To this aim, we have developed and validated an ultra-high performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) method to quantify L-DOPA, levodopa methyl ester (LDME), and the DDCI carbidopa in human plasma. The compounds were extracted by protein precipitation and samples were analyzed with a triple quadrupole mass spectrometer. The method showed good selectivity and specificity for all compounds. No carryover was observed, and dilution integrity was demonstrated. No matrix effect could be retrieved; intra-day and inter-day precision and accuracy values met the acceptance criteria. Reinjection reproducibility was assessed. The described method was successfully applied to a 45-year-old male patient to compare the pharmacokinetic behavior of an L-DOPA-based medical treatment involving commercially available Mucuna pruriens extracts and an LDME/carbidopa (100/25 mg) formulation. [ABSTRACT FROM AUTHOR]

The analysis of pesticide residues in aquatic products is challenging due to low residue levels and the complex matrix interference. In this study, we developed a simple, fast method for the trace analysis of 90 pesticides and metabolites in aquatic products. The analytes covered a wide polarity range with log Kow (log octanol-water partition coefficient) ranging from −1.2 to 6.37. Grass carp (Ctenopharyngodon idellus) and prawn (Penaeus chinensis) samples were chosen to validate the quantification method. The samples were extracted by 0.2% formic-acetonitrile, cleaned by solid-phase extraction (PRiME HLB), and analyzed by high performance liquid chromatography−tandem mass spectrometry. The results showed good linearities for the analytes and were observed in the range of 0.05–50 μg/L. The recoveries of the method were within 50.4–118.6%, with the relative standard deviations being lower than 20%. The limits of quantifications (LOQs) of the method were in the range of 0.05–5.0 μg/kg, which were superior to values compared with other research. The developed method was applied to detect pesticide residues in prawn samples from eastern coastal areas of China. Three herbicide residues of diuron, prometryn, and atrazine were detected in prawn samples. The method was sensitive and efficient, which is of significance in expanding the screening scope and improving the quantitative analysis efficiency in aquatic products. [ABSTRACT FROM AUTHOR]

Tetrodotoxin (TTX) inhibits neurotransmission in animals, and there is no specific antidote. In clinical practice in China, Althaea rosea (A. rosea flower) extract has been used to treat TTX poisoning. In this work, the efficacy of the ethyl acetate fraction extract of A. rosea flower in treating TTX poisoning in rats was investigated. A high-performance liquid chromatography–tandem mass spectrometry (LC-MS/MS) method was developed to determine nine neurotransmitters in rat brain tissue, including γ-aminobutyric acid (GABA), dopamine (DA), 5-hydroxytryptamine (5-HT), noradrenaline (NE), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxyindole-3-acetic acid (5-HIAA), epinephrine (E), and tyramine (Tyn). The detoxifying effect of A. rosea flower was verified by comparing the changes in neurotransmitters' content in brain tissue before and after poisoning in rats. The assay was performed in multiple reaction monitoring mode. The quantification method was performed by plotting an internal-standard working curve with good linearity (R2 > 0.9941) and sensitivity. Analyte recoveries were 94.04–107.53% (RSD < 4.21%). Results indicated that the levels of 5-HT, DA, E, and NE in the brains of TTX-intoxicated rats decreased, whereas the levels of GABA, Tyn, and 5-HIAA showed an opposite trend, and HVA and DOPAC were not detected. The levels of all seven neurotransmitters returned to normal after the gavage administration of ethyl acetate extract of A. rosea flower to prove that the ethyl acetate extract of A. rosea flower had a therapeutic effect on TTX poisoning. The work provided new ideas for studies on TTX detoxification. [ABSTRACT FROM AUTHOR]

Taraxaci folium and Matricariae flos plant extracts contain a wide range of bioactive compounds with antioxidant and anti-inflammatory effects. The aim of the study was to evaluate the phytochemical and antioxidant profile of the two plant extracts to obtain a mucoadhesive polymeric film with beneficial properties in acute gingivitis. The chemical composition of the two plant extracts was determined by high-performance liquid chromatography coupled with mass spectrometry. To establish a favourable ratio in the combination of the two extracts, the antioxidant capacity was determined by the method of reduction of copper ions Cu2+ from neocuprein and by reduction of the compound 1.1-diphenyl-2-2picril-hydrazyl. Following preliminary analysis, we selected the plant mixture Taraxaci folium/matricariae flos in the ratio of 1:2 (m/m), having an antioxidant capacity of 83.92% ± 0.02 reduction of free nitrogen radical of 1.1-diphenyl-2-2picril-hydrazyl reagent. Subsequently, bioadhesive films of 0.2 mm thickness were obtained using various concentrations of polymer and plant extract. The mucoadhesive films obtained were homogeneous and flexible, with pH ranging from 6.634 to 7.016 and active ingredient release capacity ranging from 85.94–89.52%. Based on in vitro analysis, the film containing 5% polymer and 10% plant extract was selected for in vivo study. The study involved 50 patients undergoing professional oral hygiene followed by a 7-day treatment with the chosen mucoadhesive polymeric film. The study showed that the film used helped accelerate the healing of acute gingivitis after treatment, with anti-inflammatory and protective action. [ABSTRACT FROM AUTHOR]

Selenium (Se) is a trace mineral found in plants with a distinct sulfuric odor that is cardioprotective and reported to have low toxicity. West Java, Indonesia, has a variety of plants with a distinct odor that are consumed raw, such as jengkol (Archidendron pauciflorum). This study is conducted to determine the Se content of jengkol using the fluorometric method, where the jengkol extract is separated, and the Se content is detected using high-pressure liquid chromatography (HPLC), combined with fluorometry. Two fractions with the highest Se concentration (A and B) are found and characterized using liquid chromatography mass spectrometry to predict the organic Se content by comparing the results with those in the external literature. The Se content of fraction (A) is found to be selenomethionine (m/z 198), gamma glutamyl-methyl-selenocysteine-(GluMetSeCys; m/z 313), and the Se-sulfur (S) conjugate of cysteine-selenoglutathione (m/z 475). Furthermore, these compounds are docked on receptors involved in cardioprotection. The receptors are peroxisome proliferator-activated receptor-γ (PPAR-γ), nuclear factor kappa-B (NF-κB), and phosphoinositide 3-kinase (PI3K/AKT). The interaction of receptor and ligan that has the lowest binding energy of the docking simulation is measured with molecular dynamic simulation. MD is performed to observe bond stability and conformation based on root mean square deviation, root mean square fluctuation, radius gyration, and MM-PBSA parameters. The results of the MD simulation show that the stability of the complex organic Se compounds tested with the receptors is lower than that of the native ligand, while the binding energy is lower than that of the native ligand based on the MM-PSBA parameter. This indicates that the predicted organic Se in jengkol, i.e., gamma-GluMetSeCys to PPAR-γ, gamma-GluMetSeCys AKT/PI3K, and Se-S conjugate of cysteine-selenoglutathione to NF-κB, has the best interaction results and provides a cardioprotection effect, compared to the molecular interaction of the test ligands with the receptors. [ABSTRACT FROM AUTHOR]

(1) Background: Citrus honey constitutes a unique monofloral honey characterized by a distinctive aroma and unique taste. The non-targeted chemical analysis can provide pivotal information on chemical markers that differentiate honey based on its geographical and botanical origin. (2) Methods: Within the PRIMA project "PLANT-B", a metabolomics workflow was established to unveil potential chemical markers of orange blossom honey produced in case study areas of Egypt, Italy, and Greece. In some of these areas, aromatic medicinal plants were cultivated to enhance biodiversity and attract pollinators. The non-targeted chemical analysis and metabolomics were conducted using ultra-high-performance liquid chromatography high-resolution mass spectrometry (UHPLC-HRMS). (3) Results: Forty compounds were disclosed as potential chemical markers, enabling the differentiation of the three orange blossom honeys according to geographical origin. Italian honey showed a preponderance of flavonoids, while in Greek honey, terpenoids and iridoids were more abundant than flavonoids, except for hesperidin. In Egyptian honey, suberic acid and a fatty acid ester derivative emerged as chemical markers. New, for honey, furan derivatives were identified using GC-MS in Greek samples. (4) Conclusions: The application of UHPLC-HRMS metabolomics combined with an elaborate melissopalynological analysis managed to unveil several potential markers of Mediterranean citrus honey potentially associated with citrus crop varieties and the local indigenous flora. [ABSTRACT FROM AUTHOR]

Anthyllis henoniana stems were harvested in two seasons: winter and spring (February and May 2021). In this study, we investigated the antioxidant (DPPH, ABTS, FRAP and TAC) and antimicrobial activities, total phenolic contents and total flavonoid contents of the obtained extracts (hexane, ethyl acetate and methanol). The results showed that ethyl acetate extract from stems harvested in winter exhibited the highest antioxidant activity, while ethyl acetate extract from the stems harvested in spring showed the most potent antibacterial and antifungal activities. To explain these differences, we investigated the phytochemical composition of these two extracts using liquid chromatography coupled with mass spectrometry. Therefore, 45 compounds were detected, from which we identified 20 compounds (flavonoids, triterpenoids, chalcones and phenolic acids); some were specific to the harvest month while others were common for both periods. Some of the major compounds detected in ethyl acetate (spring) were dihydrochalcone (Kanzonol Y, 8.2%) and flavanone (sophoraflavanone G, 5.9%), previously recognized for their antimicrobial effects. We therefore concluded that the difference in activities observed for the two harvest periods depends on the chemical composition of the extracts and the relative abundance of each compound. [ABSTRACT FROM AUTHOR]

Pentacyclic triterpenoids (PCTs), which possess a number of bioactive properties, are considered one of the most important classes of secondary plant metabolites. Their chromatographic determination in plant biomass is complicated by the need to separate a large number of structurally similar compounds belonging to several classes that differ greatly in polarity (monools, diols, and triterpenic acids). This study proposes a rapid, sensitive, and low-cost method for the simultaneous quantification of ten PCTs (3β-taraxerol, lupeol, β-amyrin, α-amyrin, betulin, erythrodiol, uvaol, betulinic, oleanolic, and ursolic acids) by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) using porous graphitic carbon (Hypercarb) as a stationary phase capable of hydrophobic retention and specific interactions with analytes. Revealing the effects of the mobile phase composition, pH, ionic strength, and column temperature on retention and selection of chromatographic conditions on this basis allowed for the effective separation of all target analytes within 8 min in gradient elution mode and attaining limits of detection in the range of 4–104 µg L−1. The developed method was fully validated and successfully tested in the determination of PCTs in common haircap (Polytrichum commune) and prairie sphagnum (Sphagnum palustre) mosses, and fireweed (Chamaenerion angustifolium) stems and leaves. [ABSTRACT FROM AUTHOR]

Plants in the genus Juniperus have been reported to produce a variety of chemical components, such as coumarins, flavonoids, lignans, sterols, and terpenoids. Here, ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) and ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) were applied to qualitatively and quantitatively analyze the major bioactive components in an ethanolic crude extract from the leaves of Juniperus chinensis L., which grows naturally in Korea. In addition, the antibacterial activity of the crude extract against pathogenic bacteria was investigated. Using LC-QTOF-MS analysis, we identified ten compounds, of which six were confirmed to be flavonoid and lignan-based components as the major bioactive components, i.e., isoquercetin, quercetin-3-O-α-l-rhamnoside, hinokiflavone, amentoflavone, podocarpusflavone A, and matairesinoside. Among them, a quantitative analysis performed using LC-MS/MS revealed that the levels of quercetin-3-O-α-l-rhamnoside and amentoflavone in the crude extract were 203.78 and 69.84 mg/g, respectively. Furthermore, the crude extract exhibited potential antibacterial activity against 10 pathogenic bacteria, with the highest antibacterial activity detected against Bordetella pertussis. Thus, further studies of the leaf extract of J. chinensis L. must be carried out to correlate the compounds present in the extract with the antibacterial activity and elucidate the mechanisms of action of this extract against bacteria. [ABSTRACT FROM AUTHOR]

This study aims to take advantage of the wine industry by-products and extract bioactive compounds from grape pomace by applying methodologies susceptible to be integrated easily into industrial workflows because of the association with standard instrumentation and facilities, while the main factors affecting the efficiency of the process have been optimized. The sampling consisted of two grape varieties: 'Touriga Nacional' and 'Sousão'. A response surface methodology (RSM) method was used to optimize the extraction conditions based on three independent variables according to the chemical characteristics and stability/lability traits associated with polyphenols; the main bioactive phytochemical in grape pomace: solvent (50%, 70%, and 90% ethanol); temperature (20 °C, 40 °C, and 60 °C); and pH (0.5% HCl, 2% HCl, and 3.5% HCl). The phytochemical profile, as well as the radical scavenging and reducing powers were determined on 27 different samples. The highest yield and antioxidant activity corresponded to extracts obtained at 60 °C using 3.5% HCl and 70% ethanol. The values for total phenols and flavonoids were 44.93 mg of gallic acid equivalents (GAE) and 22.95 mg of catechins equivalents (CE) per gram, respectively. Concerning the evaluation of antioxidant capacity using various assays such as ABTS, DPPH, and FRAP, the results obtained were 0.30, 0.43, and 0.36 mmol of Trolox equivalent antioxidant capacity (TEAC) per gram, correspondingly. The analysis of the extract obtained with the best extraction performance using these parameters via High-Performance Liquid Chromatography–Mass Spectrometry has been also performed, allowing us to identify fourteen (14) compounds, including phenolic acids (n = 3), flavonols (n = 7), and anthocyanins (n = 4). As a result of this process, the best conditions for the production of a natural and environmentally friendly dye, not only avoiding waste but also reusing these by-products, were achieved. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are hydrophobic organic contaminants that have a highly carcinogenic and mutagenic nature. This study aimed to develop and validate a sensitive analytical method to determine 8 PAHs in 51 herbal medicines (HMs) using gas chromatography (GC)-tandem mass spectrometry (MS/MS). Liquid––liquid extraction and florisil SPE cartridge purification were basically adopted for pretreatment. For the samples containing essential oil, starch grain, etc., N,N-dimethyl formamide/water mixture (9:1, v/v) was added in the extraction step. The multiple reaction monitoring (MRM) conditions were newly obtained by the infusion of reference solutions of the targeted compounds at a concentration of 100 ng/mL into the GC-MS/MS system used in this study. The 51 items were classified according to whether or not they contained essential oil. Eight PAHs were not detected in 39 (8.3%) of the 459 samples monitored. The total content of 8 PAHs ranged from 0.45 μg/kg in Anemarrhenae Rhizoma to 270.94 μg/kg in Zingiberis Rhizoma. The average content of those ranged from 0.9 μg/kg in Araliae Continentalis Radix to 110.8 μg/kg in Coptidis Rhizoma Preparata cum Vinum. The results of this study prove that the proposed method is useful for determining 8 PAHs in HMs. [ABSTRACT FROM AUTHOR]

Although dicofol has been widely banned all over the world as a kind of organochlorine contaminant, it still exists in the environment. This study developed a high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS) detection technique for dicofol, an environmental pollutant, for the first time using in-source fragmentation. The results confirmed that m/z 251 was the only precursor ion of dicofol after in-source fragmentation, and m/z 139 and m/z 111 were reasonable product ions. The main factors triggering the in-source fragmentation were the H+ content and solution conductivity when dicofol entered the mass spectrometer. Density functional theory can be used to analyze and interpret the mechanism of dicofol fragmentation reaction in ESI source. Dicofol reduced the molecular energy from 8.8 ± 0.05 kcal/mol to 1.0 ± 0.05 kcal/mol, indicating that the internal energy release from high to low was the key driving force of in-source fragmentation. A method based on HPLC-MS/MS was developed to analyze dicofol residues in environmental water. The LOQ was 0.1 μg/L, which was better than the previous GC or GC-MS methods. This study not only proposed an HPLC-MS/MS analysis method for dicofol for the first time but also explained the in-source fragmentation mechanism of compounds in ESI source, which has positive significance for the study of compounds with unconventional mass spectrometry behavior in the field of organic pollutant analysis and metabonomics. [ABSTRACT FROM AUTHOR]

As a non-traditional sample matrix, feather samples can be used to effectively monitor antibiotic addition and organismal residue levels in poultry feeding. Therefore, an ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) method was developed to simultaneously determine the residue levels of 26 quinolones in poultry feathers. The feather samples were extracted by sonication with a 1% formic acid and acetonitrile mixture in a water bath at 50 °C for 30 min, purified by the adsorption of multiple matrix impurities, dried with nitrogen, redissolved, and analyzed by UPLC-MS/MS. The linearity, limit of detection (LOD), limit of quantification (LOQ), recovery and precision were calculated. The 26 antibiotics demonstrated good linearity in the linear range. The recoveries and coefficients of variation were 78.9–110% and <13.7% at standard spiked levels of 10, 100 and 200 μg/kg, respectively. The LOD and LOQ were 0.12–1.31 and 0.96–2.60 μg/kg, respectively. The method also successfully identified quinolone residues in 50 poultry feather samples. The results showed that quinolones can accumulate and stabilize for a certain period of time after transferring from the body to the feathers of poultry. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC) has attracted much attention for its negative influence on quality of life and increased risk of colorectal cancer. Chemical and biological drugs are currently the usual treatment for UC. These drugs always induce severe side effects, or patients might become resistant to these therapies. Therefore, new therapeutic options for UC are urgently needed. In this study, we discovered the inhibitory activity of the intestinal tryptophan metabolite indole-3-carboxaldehyde (3-IAld) in dextran sulfate sodium salt (DSS)-induced UC mice by targeting the TLR4/NF-κB/p38 signaling pathway. This compound effectively protected against colon length shortening and damage induced by DSS in the colon, notably reducing the severity of inflammation. The production of inflammatory factors of TNF-α, IL-6, and IL-1β was significantly attenuated when treating with 3-IAld in vivo and vitro. This might be attributed to inhibition of the TLR4/NF-kB/p38 signaling pathway. Moreover, 3-IAld could up-regulate the expression of ZO-1 and Occludin in vivo and vitro. Meanwhile, liquid chromatography mass spectrometry (LC-MS) results showed that 3-IAld could balance the aspartate and glutamate metabolism and the lysine degradation metabolism in the serum of DSS-induced colitis mice. In conclusion, 3-IAld ameliorated the intestinal barrier dysfunction and inflammatory response in DSS-induced UC mice, balanced amino acid metabolism, and inhibited the activation of the TLR4/NF-kB/p38 signaling pathway, thereby protecting mice with colitis. [ABSTRACT FROM AUTHOR]

The intensive use of plant materials as a sustainable alternative for fish feed production, combined with their phytochemical content, which affects the growth and production characteristics of farmed fishes, necessitates their monitoring for the presence of raw materials of plant origin. This study reported herein concerns the development, validation and application of a workflow using high-performance liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) for the quantification of 67 natural phytoestrogens in plant-derived raw materials that were used to produce fish feeds. Specifically, we verified the presence of 8 phytoestrogens in rapeseed meal samples, 20 in soybean meal samples, 12 in sunflower meal samples and only 1 in wheat meal samples in quantities enabling their efficient incorporation into clusters. Among the various constituents, the soybean phytoestrogens daidzein, genistein, daidzin, glycitin, apigenin, calycosin and coumestrol, as well as the sunflower neochlorogenic, caffeic and chlorogenic phenolic acids, displayed the highest correlations with their origin descriptions. A hierarchical cluster analysis of the studied samples, based on their phytoestrogen contents, led to the efficient clustering of raw materials. The accuracy and efficiency of this clustering were tested through the incorporation of additional samples of soybean meal, wheat meal and maize meal, which verified the utilization of the phytoestrogen content as a valuable biomarker for the discrimination of raw materials used for fish feed production. [ABSTRACT FROM AUTHOR]

Large molecule protein therapeutics have steadily grown and now represent a significant portion of the overall pharmaceutical market. These complex therapies are commonly manufactured using cell culture technology. Sequence variants (SVs) are undesired minor variants that may arise from the cell culture biomanufacturing process that can potentially affect the safety and efficacy of a protein therapeutic. SVs have unintended amino acid substitutions and can come from genetic mutations or translation errors. These SVs can either be detected using genetic screening methods or by mass spectrometry (MS). Recent advances in Next-generation Sequencing (NGS) technology have made genetic testing cheaper, faster, and more convenient compared to time-consuming low-resolution tandem MS and Mascot Error Tolerant Search (ETS)-based workflows which often require ~6 to 8 weeks data turnaround time. However, NGS still cannot detect non-genetic derived SVs while MS analysis can do both. Here, we report a highly efficient Sequence Variant Analysis (SVA) workflow using high-resolution MS and tandem mass spectrometry combined with improved software to greatly reduce the time and resource cost associated with MS SVA workflows. Method development was performed to optimize the high-resolution tandem MS and software score cutoff for both SV identification and quantitation. We discovered that a feature of the Fusion Lumos caused significant relative under-quantitation of low-level peptides and turned it off. A comparison of common Orbitrap platforms showed that similar quantitation values were obtained on a spiked-in sample. With this new workflow, the amount of false positive SVs was decreased by up to 93%, and SVA turnaround time by LC-MS/MS was shortened to 2 weeks, comparable to NGS analysis speed and making LC-MS/MS the top choice for SVA workflow. [ABSTRACT FROM AUTHOR]

The presence of pesticide residues in herbs and the herbal products derived from them raises serious health concerns. This study was conducted to investigate the residual pesticide concentrations and assess potential human health risks from herbal medicines used in traditional Korean medicine clinics. A total of 40 samples of herbal decoctions were collected from 10 external herbal dispensaries. The pesticide residues were analyzed by the multiresidue method for 320 different pesticides using liquid chromatography tandem mass spectrometry (LC-MS/MS) and gas chromatography tandem mass spectrometry (GC-MS/MS). As a result of the monitoring, carbendazim was detected at 0.01 and 0.03 μg/g in eight samples and no pesticide was detected in the other herbal decoctions. Carbendazim was set for each individual item as less than 0.05 μg/g in Paeoniae radix, less than 0.05 μg/g in Cassiae semen, less than 2.0 μg/g in Lycii fructus, and less than 10 μg/g in Schisandrae fructus (dried). Therefore, the results of this study suggested that the detected pesticide residues in herbal decoctions could not be considered as posing a serious health risk. [ABSTRACT FROM AUTHOR]

Alternaria fungi are widely distributed plant pathogens that invade crop products, causing significant economic damage. In addition, toxic secondary metabolites produced by the fungi can also endanger consumers. Many of these secondary metabolites are chemically characterized as mycotoxins. In this study, Q Exactive Orbitrap mass spectrometry was used for the non-targeted analysis of the metabolome of seven Alternaria isolates cultured on Potato Carrot Agar (PCA), Potato Dextrose Agar (PDA) and Potato Sucrose Agar (PSA) medium. Due to the difficulty of detecting modified toxins, an analytical strategy with multiple visual analysis tools was also used to determine the presence of sulfate conjugated toxins, as well as to visualize the molecular network of Alternaria toxins. The results show that PSA medium exhibits more advantageous properties for the culture of Alternaria, with more toxigenic species and quantities and more obvious metabolic pathways. Based on high-resolution tandem mass spectrometry (MS/MS) data, the mycotoxins and their metabolites were mainly clustered into four groups: alternariol (AOH)/alternariol monomethyl ether (AME)/altenusin (ALU)/altenuene (ALT)/dehydroaltenusin (DHA)/Desmethyldehydroaltenusin (DMDA) families, Altertoxin-I (ATX-I) family, tentoxin (TEN) family and tenuazonic acid (TeA) family. Moreover, the PSA medium is more suitable for the accumulation of AOH, AME, ALU, ALT, DHA and DMDA, while the PDA medium is more suitable for the accumulation of ATX-I, TEN and TeA. This research may provide theoretical support for the metabolomics study of Alternaria. [ABSTRACT FROM AUTHOR]

This study aimed to optimize the brewing conditions of Shanlan rice wine (SRW) and select a suitable sterilization method. The response surface method experiment was used to optimize the brewing process of SRW. LC-MS/MS (liquid chromatography–tandem mass spectrometry) and GC-MS (gas chromatography–mass spectrometry) were used to analyze the physicochemical components, free amino acids, and flavor metabolites of the thermal-sterilized SRW and the SRW sterilized by intense pulsed light (IPL), respectively. Results showed that the optimum fermentation conditions of SRW were as follows: fermentation temperature, 24.5 °C; Qiuqu amount (the traditional yeast used to produce SRW), 0.78%; water content, 119%. Compared with the physicochemical properties of the control, those of the SRWs separately treated with two sterilization methods were slightly affected. The 60 s pulse treatment reduced the content of bitter amino acids, maintained sweet amino acids and umami amino acids in SRW, and balanced the taste of SRW. After pasteurization, the ester content in wine decreased by 90%, and the alcohol content decreased to different degrees. IPL sterilization slightly affected the ester content and increased the alcohol content. Further analysis of the main flavor metabolites showed that 60 s pulse enhanced the important flavor-producing substances of SRW. In conclusion, 60 s pulse is suitable for sterilizing this wine. [ABSTRACT FROM AUTHOR]

Eleusine indica (L.) Gaertn is a perennial herb belonging to the Poaceae family. As the only species of Eleusine found abundantly in Malaysia, it is locally known as "rumput sambau" and has been traditionally used to treat various ailments including pain relief from vaginal bleeding, hastening the placenta delivery after childbirth, asthma, hemorrhoids, urinary infection, fever, and as a tonic for flu-related symptoms. A diverse array of biological activities have been reported for the plant, such as antimicrobial, cytotoxic, anticonvulsant, anti-inflammatory, analgesic, antipyretic, and hepatoprotective action. Despite many reports on its traditional uses and biological activities, limited chemical databases are available for the plant. Thus, the aims of this study were to annotate and identify the phytochemical constituents in the methanolic extract of E. indica through tandem LCMS-based analysis techniques using MZmine, GNPS, Compound Discoverer, and SIRIUS platforms. This technique managed to identify a total of 65 phytochemicals in the extract, comprising primary and secondary metabolites, and was verified by the isolation of one of the identified phytochemicals. The structural elucidation mainly using 1D and 2D NMR as well as comparison with values in the literature confirms the isolated phytochemical to be a 3-OH anomer of loliolide, a benzofuran-type of compound, which consequently increases the level of confidence in the applied technique. The research describes a useful method for the fast and simultaneous identification of phytochemicals in E. indica, contributing to the study of the chemical properties of the genus and family. [ABSTRACT FROM AUTHOR]

The most cutting-edge and widely used techniques for sample preparation in pesticide analysis, including QuEChERS and miniaturized sample preparation methods, are described along with the unquestionable techniques GC-MS/MS and LC-MS/MS for the detection and quantification of pesticides. Hayar et al. [[8]] developed and validated a method based on QuEChERS and LC-MS/MS for the determination of 33 pesticide residues in vine leaves. Pesticides are compounds applied on crops to eliminate or control pests, diseases and weeds and it is known that their use provides unquestionable benefits in increasing agricultural production. [Extracted from the article]

Dopamine, adrenaline and octopamine are small polar molecules that play a vital role in regulatory systems. In this paper, phthalylglycyl chloride was proposed as a derivatization agent for octopamine, adrenaline and dopamine determination in urine for the first time. The derivatization procedure facilitated the use of reversed-phase liquid chromatography with positive electrospray ionization–high-resolution mass spectrometry. An LC-HRMS method was developed that provided quantification limits of 5 ng/mL and detection limits of 1.5 ng/mL for all analytes. The 95–97% yield of derivates was observed after a 10 min derivatization with phthalylglycyl chloride at pH 6.5 and 30 °C. The proposed method was successfully applied to the analysis of human urine samples. The obtained results were compared with those of conventional derivatization procedures with 9-fluorenyl-methoxycarbonyl chloride and dansyl chloride. [ABSTRACT FROM AUTHOR]

Two herbal plants, Akebia quinata D. leaf/fruit and Clitoria ternatea L. flower, well-known in traditional medicine systems, were investigated using a non-target effect-directed profiling. High-performance thin-layer chromatography (HPTLC) was combined with 11 different effect-directed assays, including two multiplex bioassays, for assessing their bioactivity. Individual active zones were heart-cut eluted for separation via an orthogonal high-performance liquid chromatography column to heated electrospray ionization high-resolution mass spectrometry (HPLC–HESI-HRMS) for tentative assignment of molecular formulas according to literature data. The obtained effect-directed profiles provided information on 2,2-diphenyl-1-picrylhydrazyl scavenging, antibacterial (against Bacillus subtilis and Aliivibrio fischeri), enzyme inhibition (tyrosinase, α-amylase, β-glucuronidase, butyrylcholinesterase, and acetylcholinesterase), endocrine (agonists and antagonists), and genotoxic (SOS-Umu-C) activities. The main bioactive compound zones in A. quinata leaf were tentatively assigned to be syringin, vanilloloside, salidroside, α-hederin, cuneataside E, botulin, and oleanolic acid, while salidroside and quinatic acids were tentatively identified in the fruit. Taraxerol, kaempherol-3-rutinoside, kaempferol-3-glucoside, quercetin-3-rutinoside, and octadecenoic acid were tentatively found in the C. ternatea flower. This straightforward hyphenated technique made it possible to correlate the biological properties of the herbs with possible compounds. The meaningful bioactivity profiles contribute to a better understanding of the effects and to more efficient food control and food safety. [ABSTRACT FROM AUTHOR]

In the quest to market increasingly safer and more potent biotherapeutic proteins, the concept of the multi-attribute method (MAM) has emerged from biopharmaceutical companies to boost the quality-by-design process development. MAM strategies rely on state-of-the-art analytical workflows based on liquid chromatography coupled to mass spectrometry (LC–MS) to identify and quantify a selected series of critical quality attributes (CQA) in a single assay. Here, we aimed at evaluating the repeatability and robustness of a benchtop LC–MS platform along with bioinformatics data treatment pipelines for peptide mapping-based MAM studies using standardized LC–MS methods, with the objective to benchmark MAM methods across laboratories, taking nivolumab as a case study. Our results evidence strong interlaboratory consistency across LC–MS platforms for all CQAs (i.e., deamidation, oxidation, lysine clipping and glycosylation). In addition, our work uniquely highlights the crucial role of bioinformatics postprocessing in MAM studies, especially for low-abundant species quantification. Altogether, we believe that MAM has fostered the development of routine, robust, easy-to-use LC–MS platforms for high-throughput determination of major CQAs in a regulated environment. [ABSTRACT FROM AUTHOR]

A simple and sensitive method for the simultaneous quantitation of prohexadione-Ca and uniconazole in the field experiment of Oryza sativa L. and Citrus reticulata Blanco was established using solid-phase extraction (SPE) with polymer anion exchange (PAX) and Florisil followed by LC-MS/MS. The method demonstrated excellent linearity (R2 > 0.999 0), trueness (recoveries between 95~105%), precision (CVs between 0.8~12%), sensitivity, and repeatability (LOQ of 0.05 and 0.01 mg/kg, respectively). Residue tests were conducted in the field at 12 representative sites in China, revealing final concentrations of prohexadione-Ca and uniconazole in brown rice, rice hull, and rice straw to be below 0.05 mg/kg, while in whole citrus fruit and citrus pulp, they were below 0.01 mg/kg. These were below the maximum residue limits specified in China. The chronic dietary risks of prohexadione-Ca and uniconazole in rice crops and citrus fruits were calculated to be 0.48% and 0.91%, respectively. Our research suggests that the chronic risk associated with the daily consumption of rice crops and citrus fruit at the recommended dosage is acceptable. [ABSTRACT FROM AUTHOR]

Selpercatinib (SLP; brand name Retevmo®) is a selective and potent RE arranged during transfection (RET) inhibitor. On 21 September 2022, the FDA granted regular approval to SLP (Retevmo, Eli Lilly, and Company). It is considered the only and first RET inhibitor for adults with metastatic or locally advanced solid tumors with RET gene fusion. In the current experiment, a highly specific, sensitive, and fast liquid chromatography tandem mass spectrometry (LC-MS/MS) method for quantifying SLP in human liver microsomes (HLMs) was developed and applied to the metabolic stability evaluation of SLP. The LC-MS/MS method was validated following the bioanalytical methodology validation guidelines outlined by the FDA (linearity, selectivity, matrix effect, accuracy, precision, carryover, and extraction recovery). SLP was detected by a triple quadrupole detector (TQD) using a positive ESI source and multiple reaction monitoring (MRM) mode for mass spectrometric analysis and estimation of analytes ions. The IS-normalized matrix effect and extraction recovery were acceptable according to the FDA guidelines for the bioanalysis of SLP. The SLP calibration standards were linear from 1 to 3000 ng/mL HLMs matrix, with a regression equation (y = 1.7298x + 3.62941) and coefficient of variation (r2 = 0.9949). The intra-batch and inter-batch precision and accuracy of the developed LC-MS/MS method were −6.56–5.22% and 5.08–3.15%, respectively. SLP and filgotinib (FLG) (internal standard; IS) were chromatographically separated using a Luna 3 µm PFP (2) stationary phase (150 × 4.6 mm) with an isocratic mobile phase at 23 ± 1 °C. The limit of quantification (LOQ) was 0.78 ng/mL, revealing the LC-MS/MS method sensitivity. The intrinsic clearance and in vitro t1/2 (metabolic stability) of SLP in the HLMs matrix were 34 mL/min/kg and 23.82 min, respectively, which proposed an intermediate metabolic clearance rate of SLP, confirming the great value of this type of kinetic experiment for more accurate metabolic stability predictions. The literature review approved that the established LC-MS/MS method is the first developed and reported method for quantifying SLP metabolic stability. [ABSTRACT FROM AUTHOR]

PLK-1 (Polo-like kinase-1) plays an essential role in cytokinesis, and its aberrant expression is considered to be keenly associated with a wide range of cancers. It has been selected as an appealing target and small-molecule inhibitors have been developed and studied in clinical trials. Unfortunately, most have been declared as failures due to the poor therapeutic response and off-target toxicity. In the present study, a novel potent PLK-1 inhibitor, compound 7a, was designed and synthetized. 1H NMR, 13C NMR, 19F NMR and mass spectrum were comprehensively used for the compound characterization. The compound exhibited higher potency against PLK-1 kinase, HCT-116 and NCI-H2030 cell lines than the positive control. Molecular docking indicated that the binding mode that the ATP binding site of PLK-1 was occupied by the compound. Then, a UHPLC-MS/MS method was established and validated to explore the pharmacokinetic behavior of the drug candidate. The method had good selectivity, high sensitivity and wide linearity. The exposure increased linearly with the dose, but the oral bioavailability was not satisfactory enough. Then, the metabolism was studied using liver microsomes by UHPLC-Q-Orbitrap/HRMS. Our research first studied the pharmacokinetic metabolic characteristics of 7a and may serve as a novel lead compound for the development of PLK-1 inhibitors. [ABSTRACT FROM AUTHOR]

Supramolecular and biocompatible hydrogels with a tunable pH ranging from 5.5 to 7.6 lead to a wide variety of formulations useful for many different topical applications compatible with the skin pH. An in vitro viability/cytotoxicity test of the gel components demonstrated that they are non-toxic, as the cells continue to proliferate after 48 h. An analysis of the mechanical properties demonstrates that the hydrogels have moderate strength and an excellent linear viscoelastic range with the absence of a proper breaking point, confirmed with thixotropy experiments. Two cosmetic active peptides (Trifluoroacetyl tripeptide-2 and Palmitoyl tripeptide-5) were successfully added to the hydrogels and their transdermal permeation was analysed with Franz diffusion cells. The liquid chromatography-mass spectrometry (HPLC-MS) analyses of the withdrawn samples from the receiving solutions showed that Trifluoroacetyl tripeptide-2 permeated in a considerable amount while almost no transdermal permeation of Palmitoyl tripeptide-5 was observed. [ABSTRACT FROM AUTHOR]

Jigucao capsules (JGCC) have the effects of soothing the liver and gallbladder and clearing heat and detoxification. It is a good medicine for treating acute and chronic hepatitis cholecystitis with damp heat of the liver and gallbladder. However, the existing quality standard of JGCC does not have content determination items, which is not conducive to quality control. In this study, serum pharmacochemistry technology and UNIFI data processing software were used to identify the blood prototype components and metabolites under the condition of the obvious drug effects of JGCC, and the referenced literature reports and the results from in vitro analysis of JGCC in the early stage revealed a total of 43 prototype blood components and 33 metabolites in JGCC. Quality markers (Q-markers) were discovered, such as abrine, trigonelline, hypaphorine and isoschaftoside. In addition, ultra-high-performance liquid chromatography–triple quadrupole mass spectrometry (UPLC-QQQ-MS) was used to determine the active ingredients in JGCC. The components of quantitative analysis have good correlation in the linear range with R2 ≥ 0.9993. The recovery rate is 93.15%~108.92% and the relative standard deviation (RSD) is less than 9.48%. The established UPLC-MS/MS quantitative analysis method has high sensitivity and accuracy, and can be used for the quality evaluation of JGCC. [ABSTRACT FROM AUTHOR]

Finally, an IT-SPME method using extraction tubes filled with hydrophilic, superhydrophilic, superhydrophobic and UV-irradiated superhydrophilic Ti wires as sorbents was used for on-line IT-SPME LC-UV analysis of six estrogen-like hormones in water samples [[15]]. HS-SPME GC-MS also identified 22 VOCs in the essential oil of dioecious aroeira seeds of I Myracrodruon urundeuva i using HS-SPME GC-MS, and their anti-inflammatory properties were analyzed using a chemoinformatics approach [[4]]. Furthermore, an automated analysis system that couples on-line IT-SPME and LC-MS/MS was constructed using an open-tube fused silica capillary with a coated inner surface as the extraction device, enabling simultaneous selective and sensitive analysis of the metabolism of sulfated steroids in saliva samples [[12]]. For example, HS-SPME GC-MS identified wheat- and insect-specific VOCs, including benzoquinone homologues, released by three stored grain pests, suggesting that these compounds can act as biomarkers of crop damage [[6]]. [Extracted from the article]

Green tea is a popular beverage around the world and possesses a unique flavor. The flavor qualities of green tea are closely related to its grade and this relationship has not yet been studied. Three baked green teas with similar flavor were studied, namely, Huangshan Maofeng, Taiping Houkui, and Shucheng Xiaolanhua. A total of 34 odor compounds were identified by solid phase microextraction (SPME) combined with two-dimensional comprehensive gas chromatography–olfactometry–mass spectrometry analysis (GC×GC-O-MS). The results of the clustering analysis showed that the content of D-limonene and linalool in the high-grade (Grade A) tea was much higher than the content in other grades, so they were identified as odor markers of Grade A baked green tea. The taste components of different grades of green tea infusion were analyzed by high-performance liquid chromatography–mass spectrometry (HPLC–MS) and HPLC. A combination of clustering analysis, principal component analysis (PCA), and orthogonal partial least squares discrimination analysis (OPLS-DA) indicated that galloylglucose, digalloylglucose, trigalloyglucose, strictinin, and gallic acid could be used as taste markers of Grade A baked green tea. Therefore, the results in this paper reveal the substances responsible for the odor and taste markers of high-grade baked green tea. [ABSTRACT FROM AUTHOR]

Vancomycin (VAN), meropenem (MER), and valproate (VPA) are commonly used to treat intracranial infection post-craniotomy and prevent associated epilepsy. To monitor their levels, we developed a novel bioassay based on liquid chromatography–tandem mass spectrometry (LC–MS/MS) for simultaneous determination of these three drugs in human serum and cerebrospinal fluid (CSF). Sample preparation by protein precipitation using acetonitrile was followed by HPLC on a Zorbax 300SB-C8 column (150 mm × 4.6 mm, 5 μm) maintained at 40 °C. The lower limit of quantification (LLOQ) was 5 ng/mL for MER, 0.1 μg/mL for VAN, and 1 μg/mL for VPA in serum and 50 ng/mL for MER, 1 μg/mL for VAN, and 2 μg/mL for VPA in CSF. This method was validated with satisfactory linearity, sensitivity, precision, accuracy, recovery, matrix effects, and stability for all analytes. The assay was then successfully applied to evaluate VPA, MER, and VAN levels in serum and CSF from patients with intracranial infection administrated by intrathecal injection. Compared with intravenous injections, an intrathecal injection can provide sufficient therapeutic effects even if the CSF levels did not reach the effective concentration reported. Our method provided a detection tool to study the effective concentrations of these three drugs in CSF from patients administered via intrathecal injection. [ABSTRACT FROM AUTHOR]

Panax notoginseng (Burk) F. H. Chen is a traditional Chinese medicinal and edible plant. However, Panax notoginseng flower (PNF) is rarely used. Therefore, the purpose of this study was to explore the main saponins and the anti-inflammatory bioactivity of PNF saponins (PNFS). We explored the regulation of cyclooxygenase 2 (COX–2), a key mediator of inflammatory pathways, in human keratinocyte cells treated with PNFS. A cell model of UVB-irradiation-induced inflammation was established to determine the influence of PNFS on inflammatory factors and their relationship with LL–37 expression. An enzyme-linked immunosorbent assay and Western blotting analysis were used to detect the production of inflammatory factors and LL37. Finally, liquid chromatography–tandem mass spectrometry was employed to quantify the main active components (ginsenosides Rb1, Rb2, Rb3, Rc, Rd, Re, Rg1, and notoginsenoside R1) in PNF. The results show that PNFS substantially inhibited COX–2 activity and downregulated the production of inflammatory factors, indicating that they can be used to reduce skin inflammation. PNFS also increased the expression of LL-37. The contents of ginsenosides Rb1, Rb2, Rb3, Rc, and Rd in PNF were much higher than those of Rg1, and notoginsenoside R1. This paper provides data in support of the application of PNF in cosmetics. [ABSTRACT FROM AUTHOR]

Furosemide is a widely used loop diuretic in the treatment of congestive heart failure and edema. During the preparation of furosemide, a new process-related impurity G in the levels ranging from 0.08% to 0.13% was detected in pilot batches by a new high performance liquid chromatography (HPLC) method. The new impurity was isolated and characterized by comprehensive analysis of FT-IR, Q-TOF/LC-MS, 1D-NMR (1H, 13C, and DEPT), and 2D-NMR (1H-1H-COSY, HSQC, and HMBC) spectroscopy data. The possible formation pathway of impurity G was also discussed in detail. Moreover, a novel HPLC method was developed and validated for the determination of impurity G and the other six known impurities registered in the European Pharmacopoeia as per ICH guidelines. The HPLC method was validated with respect to system suitability, linearity, the limit of quantitation, the limit of detection, precision, accuracy, and robustness. The characterization of impurity G and the validation of its quantitative HPLC method were reported for the first time in this paper. Finally, the toxicological properties of impurity G were predicted by the in silico webserver ProTox-II. [ABSTRACT FROM AUTHOR]

XYY-CP1106, a candidate compound synthesized from a hybrid of hydroxypyridinone and coumarin, has been shown to be remarkably effective in treating Alzheimer's disease. A simple, rapid and accurate high-performance liquid chromatography coupled with the triple quadrupole mass spectrometer (LC-MS/MS) method was established in this study to elucidate the pharmacokinetics of XYY-CP1106 after oral and intravenous administration in rats. XYY-CP1106 was shown to be rapidly absorbed into the blood (Tmax, 0.57–0.93 h) and then eliminated slowly (T1/2, 8.26–10.06 h). Oral bioavailability of XYY-CP1106 was (10.70 ± 1.72)%. XYY-CP1106 could pass through the blood–brain barrier with a high content of (500.52 ± 260.12) ng/g at 2 h in brain tissue. The excretion results showed that XYY-CP1106 was mainly excreted through feces, with an average total excretion rate of (31.14 ± 0.05)% in 72 h. In conclusion, the absorption, distribution and excretion of XYY-CP1106 in rats provided a theoretical basis for subsequent preclinical studies. [ABSTRACT FROM AUTHOR]

Alvocidib (AVC; flavopiridol) is a potent cyclin-dependent kinase inhibitor used in patients with acute myeloid leukemia (AML). The FDA has approved orphan drug designation to AVC for treating patients with AML. In the current work, the in silico calculation of AVC metabolic lability was done using the P450 metabolism module of the StarDrop software package, that is expressed as a composite site lability (CSL). This was followed by establishing an LC-MS/MS analytical method for AVC estimation in human liver microsomes (HLMs) to assess metabolic stability. AVC and glasdegib (GSB), used as internal standards (IS), were separated utilizing a C18 column (reversed chromatography) with an isocratic mobile phase. The lower limit of quantification (LLOQ) was 5.0 ng/mL, revealing the sensitivity of the established LC-MS/MS analytical method that exhibited a linearity in the range 5–500 ng/mL in the HLMs matrix with correlation coefficient (R2 = 0.9995). The interday and intraday accuracy and precision of the established LC-MS/MS analytical method were −1.4% to 6.7% and −0.8% to 6.4%, respectively, confirming the reproducibility of the LC-MS/MS analytical method. The calculated metabolic stability parameters were intrinsic clearance (CLint) and in vitro half-life (t1/2) of AVC at 26.9 µL/min/mg and 25.8 min, respectively. The in silico results from the P450 metabolism model matched the results generated from in vitro metabolic incubations; therefore, the in silico software can be used to predict the metabolic stability of the drugs, saving time and resources. AVC exhibits a moderate extraction ratio, indicating reasonable in vivo bioavailability. The established chromatographic methodology was the first LC-MS/MS method designed for AVC estimation in HLMs matrix that was applied for AVC metabolic stability estimation. [ABSTRACT FROM AUTHOR]

This study aimed to establish a simple and sensitive analytical method to simultaneously quantify donepezil (DPZ) and tadalafil (TAD) in rat plasma using lansoprazole (LPZ) as an internal standard (IS) by using liquid chromatography tandem mass spectrometry. The fragmentation pattern of DPZ, TAD, and IS was elucidated using multiple reaction monitoring in electrospray ionization positive ion mode for the quantification of precursor to production at m/z 380.1 → 91.2 for DPZ, m/z 390.2 → 268.1 for TAD, and m/z 370.3 → 252.0 for LPZ. The extracted DPZ and TAD from plasma using acetonitrile-induced protein precipitation was separated using Kinetex C18 (100 × 2.1 mm, 2.6 µm) column with a gradient mobile phase system consisting of 2 mM ammonium acetate and 0.1% formic acid in acetonitrile at a flow rate of 0.25 mL/min for 4 min. The selectivity, lower limit of quantification, linearity, precision, accuracy, stability, recovery, and matrix effect of this developed method was validated according to the guidelines of the U.S. Food and Drug Administration and the Ministry of Food and Drug Safety of Korea. The established method achieved acceptance criteria in all validation parameters, ensuring reliability, reproducibility, and accuracy, and was successfully implemented in a pharmacokinetic study on the co-administration of DPZ and TAD orally in rats. [ABSTRACT FROM AUTHOR]

The new direct oral anticoagulants (DOACs) are increasingly used to treat and prevent thromboembolic disorders, and monitoring concentrations may be valuable in some special scenarios to prevent clinical adverse events. This study aimed to develop generic methods for the rapid and simultaneous analysis of four DOACs in human plasma and urine. Protein precipitation and one-step dilution were used to prepare the plasma and urine; the extracts were injected to ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for analysis. Chromatographic separation was performed on an Acquity™ UPLC BEH C18 column (2.1 × 50 mm, 1.7 μm) with gradient elution of 7 min. A triple quadrupole tandem mass spectrometer with an electrospray ionization source was employed to analyze DOACs in a positive ion mode. The methods showed great linearity in the plasma (1~500 ng/mL) and urine (10~10,000 ng/mL) for all analytes (R2 ≥ 0.99). The intra- and inter-day precision and accuracy were within acceptance criteria. The matrix effect and extraction recovery were 86.5~97.5% and 93.5~104.7% in the plasma, while 97.0~101.9% and 85.1~99.5% in the urine. The stability of samples during the routine preparation and storage were within the acceptance criteria of less than ±15%. The methods developed were accurate, reliable, and simple for the rapid and simultaneous measurement of four DOACs in human plasma and urine, and successfully applied to patients and subjects with DOACs therapy for anticoagulant activity assessment. [ABSTRACT FROM AUTHOR]

The determination of the selected antihypertensive drugs in human plasma samples with the novel solvent front position extraction (SFPE) technique is presented. The SFPE procedure combined with LC-MS/MS analysis was used for the first time to prepare a clinical sample containing the drugs mentioned above from different therapeutic groups. The effectiveness of our approach was compared with the precipitation method. The latter technique is usually used to prepare biological samples in routine laboratories. During the experiments, the substances of interest and the internal standard were separated from other matrix components using a prototype horizontal chamber for thin-layer chromatography/high-performance thin-layer chromatography (TLC/HPTLC) with a moving pipette powered by a 3D mechanism, which distributed the solvent on the adsorbent layer. Detection of the six antihypertensive drugs was performed by liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS) in multiple reaction monitoring (MRM) mode. Results obtained by SFPE were very satisfactory (linearity R2 ≥ 0.981; %RSD ≤ 6%; LOD and LOQ were in the range of 0.06–9.78 ng/mL and 0.17–29.64 ng/mL, respectively). The recovery was in the range of 79.88–120.36%. Intra-day and inter-day precision had a percentage coefficient of variation (CV) in the range of 1.10–9.74%. The procedure is simple and highly effective. It includes the automation of TLC chromatogram development, which significantly reduced the number of manual operations performed, the time of sample preparation and solvent consumption. [ABSTRACT FROM AUTHOR]

Leontopodium alpinum is an important source of raw material for food, medicine, and modern cosmetics. The purpose of this study was to develop a new application for protection against blue light damage. To investigate the effects and mechanism of action of Leontopodium alpinum callus culture extract (LACCE) on blue light damage, a blue-light-induced human foreskin fibroblast damage model was established. The contents of collagen (COL-I), matrix metalloproteinase 1 (MMP-1), and opsin 3 (OPN3) were detected using enzyme-linked immunosorbent assays and Western blotting. The calcium influx and reactive oxygen species (ROS) levels were measured via flow cytometry and the results showed that the LACCE (10–15 mg/mL) promoted the production of COL-I, inhibited the secretion of MMP-1, OPN3, ROS and calcium influx, and may play a role in inhibiting the activation of blue light on the OPN3-calcium pathway. Thereafter, high-performance liquid chromatography and ultra-performance liquid chromatography–tandem mass spectrometry were used to quantitatively analyze the contents of nine active ingredients in the LACCE. The results indicated that LACCE has an anti-blue-light-damage effect and provides theoretical support for the development of new raw materials in the natural food, medicine, and skin care industries. [ABSTRACT FROM AUTHOR]

Carnivorous plants are able to attract small animals or protozoa and retain them in their specialized traps. Later, the captured organisms are killed and digested. The nutrients contained in the prey bodies are absorbed by the plants to use for growth and reproduction. These plants produce many secondary metabolites involved in the carnivorous syndrome. The main purpose of this review was to provide an overview of the secondary metabolites in the family Nepenthaceae and Droseraceae, which were studied using modern identification techniques, i.e., high-performance liquid chromatography or ultra-high-performance liquid chromatography with mass spectrometry and nuclear magnetic resonance spectroscopy. After literature screening, there is no doubt that tissues of species from the genera Nepenthes, Drosera, and Dionaea are rich sources of secondary metabolites that can be used in pharmacy and for medical purposes. The main types of the identified compounds include phenolic acids and their derivatives (gallic, protocatechuic, chlorogenic, ferulic, p-coumaric acids, gallic, hydroxybenzoic, vanillic, syringic caffeic acids, and vanillin), flavonoids (myricetin, quercetin, and kaempferol derivatives), including anthocyanins (delphinidin-3-O-glucoside, cyanidin-3-O-glucoside, and cyanidin), naphthoquinones (e.g., plumbagin, droserone, and 5-O-methyl droserone), and volatile organic compounds. Due to the biological activity of most of these substances, the importance of the carnivorous plant as a pharmaceutical crop will increase. [ABSTRACT FROM AUTHOR]

Nowadays, it is vital to have new, complete, and rapid methods to screen and follow pharmacotoxicological and forensic cases. In this context, an important role is undoubtedly played by liquid chromatography-tandem mass spectrometry (LC-MS/MS) thanks to its advanced features. This instrument configuration can offer comprehensive and complete analysis and is a very potent analytical tool in the hands of analysts for the correct identification and quantification of analytes. The present review paper discusses the applications of LC-MS/MS in pharmacotoxicological cases because it is impossible to ignore the importance of this powerful instrument for the rapid development of pharmacological and forensic advanced research in recent years. On one hand, pharmacology is fundamental for drug monitoring and helping people to find the so-called "personal therapy" or "personalized therapy". On the other hand, toxicological and forensic LC-MS/MS represents the most critical instrument configuration applied to the screening and research of drugs and illicit drugs, giving critical support to law enforcement. Often the two areas are stackable, and for this reason, many methods include analytes attributable to both fields of application. In this manuscript, drugs and illicit drugs were divided in separate sections, with particular attention paid in the first section to therapeutic drug monitoring (TDM) and clinical approaches with a focus on central nervous system (CNS). The second section is focused on the methods developed in recent years for the determination of illicit drugs, often in combination with CNS drugs. All references considered herein cover the last 3 years, except for some specific and peculiar applications for which some more dated but still recent articles have been considered. [ABSTRACT FROM AUTHOR]

β2-agonists are a class of synthetic sympathomimetic drugs with acute poisoning effects if consumed as residues in foods. To improve the efficiency of sample preparation and to overcome matrix-dependent signal suppression in the quantitative analysis of four β2-agonists (clenbuterol, ractopamine, salbutamol, and terbutaline) residues in fermented ham, an enzyme digestion coupled cation exchange purification method for sample preparation was established using ultra-high performance liquid chromatography and tandem mass spectrometry (UHPLC-MS/MS). Enzymatic digests were subject to cleanup treatment on three different solid phase extraction (SPE) columns and a polymer-based strong cation resin (SCR) cartridge containing sulfonic resin was found to be optimal compared with silica-based sulfonic acid and polymer sulfonic acid resins based SPEs. The analytes were investigated over the linear range of 0.5 to 10.0 μg/kg with recovery rates of 76.0–102.0%, and a relative standard deviation of 1.8–13.3% (n = 6). The limit of detection (LOD) and the limit of quantification (LOQ) were 0.1 μg/kg and 0.3 μg/kg, respectively. This newly developed method was applied to the detection of β2-agonist residues in 50 commercial ham products and only one sample was found to contain β2-agonist residues (clenbuterol at 15.2 µg/kg). [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) consists of the progressive degeneration of motor neurons, caused by poorly understood mechanisms for which there is no cure. Some of the cellular perturbations associated with ALS can be detected in peripheral cells, including lymphocytes from blood. A related cell system that is very suitable for research consists of human lymphoblastoid cell lines (LCLs), which are immortalized lymphocytes. LCLs that can be easily expanded in culture and can be maintained for long periods as stable cultures. We investigated, on a small set of LCLs, if a proteomics analysis using liquid chromatography followed by tandem mass spectrometry reveals proteins that are differentially present in ALS versus healthy controls. We found that individual proteins, the cellular and molecular pathways in which these proteins participate, are detected as differentially present in the ALS samples. Some of these proteins and pathways are already known to be perturbed in ALS, while others are new and present interest for further investigations. These observations suggest that a more detailed proteomics analysis of LCLs, using a larger number of samples, represents a promising approach for investigating ALS mechanisms and to search for therapeutic agents. Proteomics data are available via ProteomeXchange with identifier PXD040240. [ABSTRACT FROM AUTHOR]