A UPLC-MS/MS method for quantification of metabolites in the ethylene biosynthesis pathway and its biological validation in Arabidopsis.

The plant hormone ethylene is of vital importance in the regulation of plant development and stress responses. Recent studies revealed that 1-aminocyclopropane-1-carboxylic acid (ACC) plays a role beyond its function as an ethylene precursor. However, the absence of reliable methods to quantify ACC and its conjugates malonyl-ACC (MACC), glutamyl-ACC (GACC), and jasmonyl-ACC (JA-ACC) hinders related research. Combining synthetic and analytical chemistry, we present the first, validated methodology to rapidly extract and quantify ACC and its conjugates using ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). Its relevance was confirmed by application to Arabidopsis mutants with altered ACC metabolism and wild-type plants under stress. Pharmacological and genetic suppression of ACC synthesis resulted in decreased ACC and MACC content, whereas induction led to elevated levels. Salt, wounding, and submergence stress enhanced ACC and MACC production. GACC and JA-ACC were undetectable in vivo; however, GACC was identified in vitro, underscoring the broad applicability of the method. This method provides an efficient tool to study individual functions of ACC and its conjugates, paving the road toward exploration of novel avenues in ACC and ethylene metabolism, and revisiting ethylene literature in view of the recent discovery of an ethylene-independent role of ACC.

The effect of shikonin on the metabolism of lapatinib in vitro, and in vivo.

PURPOSE: The purpose of this study was to develop an assay for simultaneous determination of lapatinib and its metabolites (N-dealkylated lapatinib and O-dealkylated lapatinib) by ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS), and to determine the interaction between shikonin and lapatinib in vitro, in vivo, in silico and its mechanism of action. METHODS: A new UPLC-MS/MS method for the determination of the concentrations of lapatinib and its metabolites was developed. In vivo, Sprague-Dawley (SD) rats were given lapatinib with or without shikonin. In vitro, to study the interaction mechanism, rat liver microsomes (RLMs), human liver microsomes (HLMs) and recombinant human CYP3A4.1 were used for determining enzyme kinetics. Lastly, we used in silico molecular docking to investigate the molecular mechanism of inhibition. RESULTS: The selectivity, precision, accuracy, stability, matrix effect and recovery of UPLC-MS/MS all met the requirements of quantitative analysis of biological samples. Administration of lapatinib combined with shikonin resulted in significantly increased pharmacokinetic parameters (AUC(0-t) and Cmax) of lapatinib, indicating that shikonin increased the exposure of lapatinib in rats. Moreover, in vitro kinetic measurements indicated that shikonin was a time-independent inhibitor, which inhibited the metabolism of lapatinib through a competitive mechanism in RLMs, while noncompetitive inhibition type in both HLMs and CYP3A4.1. Molecular docking analysis further verified the non-competitive inhibition of shikonin on lapatinib in CYP3A4.1. CONCLUSION: We developed an UPLC-MS/MS assay for simultaneous determination of lapatinib and its metabolites. It could be successfully applied to the study of pharmacokinetic interaction of shikonin on the inhibition of lapatinib metabolism in vivo and in vitro. In the end, further studies are needed to determine if such interactions are indeed valid in humans and if the interaction is clinically relevant.

Determination of acetochlor by UPLC-MS3 in cells and its application to a cellular pharmacokinetic study.

The aim of this work was to develop a fast, simple, and reliable UPLC-MS3 method for the sensitive detection of acetochlor in biological samples. In MS3 mode, the ion transition m/z 270.1 â†’ 224.1→148.1 was chosen for quantification with butachlor as the internal standard. In the UPLC system, separation was performed on a UPLC column (2.1 × 50 mm ID, 1.7 µm) with 0.1 % FA in water and acetonitrile as mobile phases. After simple protein precipitation via acetonitrile, the method was well validated with good linearity (0.5-20 ng/mL, r > 0.995), accuracy (-3.70 %-2.98 %), and precision (<15 %). The selectivity and sensitivity were improved obviously in MS3 mode than that in MRM mode. The developed UPLC-MS3 method was successfully applied to the cellular pharmacokinetics study of acetochlor in MCF-7 cells.

Plasma oxylipin profiles reflect Parkinson's disease stage.

Derivatives of polyunsaturated fatty acids (PUFAs), also known as oxylipins, are key participants in regulating inflammation. Neuroinflammation is involved in many neurodegenerative diseases, including Parkinson's disease. The development of ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) facilitated the study of oxylipins on a system level, i.e., the analysis of oxylipin profiles. We analyzed oxylipin profiles in the blood plasma of 36 healthy volunteers (HC) and 73 patients with Parkinson's disease (PD), divided into early (L\M, 29 patients) or advanced (H, 44 patients) stages based on the Hoehn and Yahr scale. Among the 40 oxylipins detected, we observed a decrease in the concentration of arachidonic acid (AA) and AA derivatives, including anandamide (AEA) and Leukotriene E4 (LTE4), and an increase in the concentration of hydroxyeicosatetraenoic acids 19-HETE and 12-HETE (PD vs HC). Correlation analysis of gender, age of PD onset, and disease stages revealed 20 compounds the concentration of which changed depending on disease stage. Comparison of the acquired oxylipin profiles to openly available PD patient brain transcriptome datasets showed that plasma oxylipins do not appear to directly reflect changes in brain metabolism at different disease stages. However, both the L\M and H stages are characterized by their own oxylipin profiles - in patients with the H stage oxylipin synthesis is increased, while in patients with L\M stages oxylipin synthesis decreases compared to HC. This suggests that different therapeutic approaches may be more effective for patients at early versus late stages of PD.

Low-background interference detection of glyphosate, glufosinate, and AMPA in foods using UPLC-MS/MS without derivatization.

The abuse of herbicides has emerged as a great threat to food security. Herein, a low-background interference detection method based on UPLC-MS was developed for the simultaneous determination of glufosinate, glyphosate, and its metabolite aminomethylphosphonic acid (AMPA) in foods. Initially, this study proposed a simple and rapid pretreatment method, utilizing water extraction and PRiME HLB purification to isolate glyphosate, glufosinate, and AMPA from food samples. After the optimization of pretreatment conditions, the processed samples are then analyzed directly by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS) without pre-column derivatization. The method can effectively reduce interference from by-products of pre-column derivatization and background substrates of food sample, showing low matrix effects (ME) ranging from - 24.83 to 32.10%. Subsequently, the method has been validated by 13 kinds of food samples. The recoveries of the three herbicides in the food samples range from 84.2 to 115.6%. The limit of detection (LOD) is lower to 0.073 mg/kg, 0.017 mg/kg, and 0.037 mg/kg, respectively. Moreover, the method shows an excellent reproducibility with relative standard deviations (RSD) within 16.9%. Thus, the method can provide high trueness, reproducibility, sensitivity, and interference-free detection to ensure human health safety.

A robust ultra-performance liquid chromatography-tandem mass spectrometry method for simultaneous determination of 10 components in glutathione cycle.

Glutathione (GSH) is an important antioxidant that is generated and degraded via the GSH cycle. Quantification of the main components in the GSH cycle is necessary to evaluate the process of GSH. In this study, a robust ultra-performance liquid chromatography-tandem mass spectrometry method for the simultaneous quantification of 10 components (GSH; γ-glutamylcysteine; cysteinyl-glycine; n-acetylcysteine; homocysteine; cysteine; cystine; methionine; glutamate; pyroglutamic acid) in GSH cycle was developed. The approach was optimized in terms of derivative, chromatographic, and spectrometric conditions as well as sample preparation. The unstable thiol groups of GSH, γ-glutamylcysteine, cysteinyl-glycine, n-acetylcysteine, cysteine, and homocysteine were derivatized by n-ethylmaleimide. The derivatized and underivatized analytes were separated on an amino column with gradient elution. The method was further validated in terms of selectivity (no interference), linearity (R2 > 0.99), precision (% relative standard deviation [RSD%] range from 0.57 to 10.33), accuracy (% relative error [RE%] range from -3.42 to 10.92), stability (RSD% < 5.68, RE% range from -2.54 to 4.40), recovery (RSD% range from 1.87 to 7.87) and matrix effect (RSD% < 5.42). The validated method was applied to compare the components in the GSH cycle between normal and oxidative stress cells, which would be helpful in clarifying the effect of oxidative stress on the GSH cycle.

A comprehensive strategy based on ultra-high performance liquid chromatography with diode array detector fingerprinting and multi-component ultra-performance liquid chromatography with tandem mass spectrometry technology for quality control of Jiawei Huoxiang Zhengqi Pill.

Jiawei Huoxiang Zhengqi Pill (JHZP) is a commonly used Chinese patent medicine for the clinical treatment of headache, dizziness, chest tightness as well as abdominal distension, and pain caused by wind-cold flu. In this study, a comprehensive strategy combining ultra-high performance liquid chromatography with diode array detector (UHPLC-DAD) fingerprinting and multi-component quantitative analysis was established and validated for quality evaluation of JHZP. A total of 49 characteristic common peaks were selected in a chromatographic fingerprinting study to assess the similarity of 15 batches of JHZP. Furthermore, 109 compounds were identified or preliminarily identified from JHZP by coupling with an advanced hybrid linear ion trap-Orbitrap mass spectrometer. For quantification, the optimized ultra-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method was employed for the simultaneous determination of 13 target compounds within 12 min. The sensitivity, precision, reproducibility, and accuracy of the method were satisfactory. This validated UPLC-MS/MS method was successfully applied to analyzing 15 batches of JHZP. The proposed comprehensive strategy combining UHPLC-DAD fingerprinting and multi-component UPLC-MS/MS analysis proved to be highly efficient, accurate, and reliable for the quality evaluation of JHZP, which can be considered as a reference for the overall quality evaluation of other Chinese herbal formulations.

Direct injection ultra-performance liquid chromatography-tandem mass spectrometry for the high-throughput determination of etomidate and etomidate acid in wastewater.

Etomidate (ET), a hypnotic agent used for the induction of anesthesia, is rapidly metabolized to etomidate acid (ETA) in the liver. Recently, ET has become one of the most serious alternative drugs of abuse in China. Therefore, an urgent need exists to develop a fast and convenient analysis method for monitoring ET. The current work presents a simple, fast, and sensitive direct injection method for the determination of ET and ETA in wastewater. After the optimization of the ultra-performance liquid chromatography-tandem mass spectrometry and sample filtration conditions, the method exhibited satisfactory limits of detection (1 ng/L) and good filtration loss. The validated method was successfully applied to determine the concentrations of ET and ETA in wastewater samples (n = 245) from several wastewater treatment plants in China. The concentrations of the targets in positive samples ranged from less than the lower limits of quantitation to 47.71 ng/L. The method can meet ET monitoring and high-throughput analysis requirements.

Phytochemical Composition, Anti-Inflammatory Property, and Anti-Atopic Effect of Chaetomorpha linum Extract.

Utilizing plant-based resources, particularly their by-products, aligns with sustainability principles and circular bioeconomy, contributing to environmental preservation. The therapeutic potential of plant extracts is garnering increasing interest, and this study aimed to demonstrate promising outcomes from an extract obtained from an underutilized plant waste. Chaetomorpha linum, an invasive macroalga found in the Orbetello Lagoon, thrives in eutrophic conditions, forming persistent mats covering approximately 400 hectares since 2005. The biomass of C. linum undergoes mechanical harvesting and is treated as waste, requiring significant human efforts and economic resources-A critical concern for municipalities. Despite posing challenges to local ecosystems, the study identified C. linum as a natural source of bioactive metabolites. Phytochemical characterization revealed lipids, amino acids, and other compounds with potential anti-inflammatory activity in C. linum extract. In vitro assays with LPS-stimulated RAW 264.7 and TNF-α/IFN-γ-stimulated HaCaT cells showed the extract inhibited reactive oxygen species (ROS), nitric oxide (NO), and prostaglandin E2 (PGE2) productions, and reduced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions via NF-κB nuclear translocation, in RAW 264.7 cells. It also reduced chemokines (TARC/CCL17, RANTES/CCL5, MCP-1/CCL2, and IL-8) and the cytokine IL-1ß production in HaCaT cells, suggesting potential as a therapeutic candidate for chronic diseases like atopic dermatitis. Finally, in silico studies indicated palmitic acid as a significant contributor to the observed effect. This research not only uncovered the untapped potential of C. linum but also laid the foundation for its integration into the circular bioeconomy, promoting sustainable practices, and innovative applications across various industries.

Ultra-high-performance liquid chromatography-mass spectrometry combined with molecular docking and molecular dynamics simulation reveals the source of bitterness in the traditional Chinese medicine formula Runchang-Tongbian.

The Runchang-Tongbian (RCTB) formula is a traditional Chinese medicine (TCM) formula consisting of four herbs, namely Cannabis Fructus (Huomaren), Rehmanniae Radix (Dihuang), Atractylodis Macrocephalae Rhizoma (Baizhu), and Aurantii Fructus (Zhiqiao). It is widely used clinically because of its beneficial effect on constipation. However, its strong bitter taste leads to poor patient compliance. The bitter components of TCM compounds are complex and numerous, and inhibiting the bitter taste of TCM has become a major clinical challenge. Here, we use ultra-high-performance liquid chromatography coupled with mass spectrometry (UPLC-MS) and high-resolution mass spectrometry to identify 59 chemical components in the TCM compound RCTB formula. Next, four bitter taste receptors, TAS2R39, TAS2R14, TAS2R7, and TAS2R5, which are tightly bound to the compounds in RCTB, were screened as molecular docking receptors using the BitterX database. The top-three-scoring receptor-small-molecule complexes for each of the four receptors were selected for molecular dynamics simulation. Finally, seven bitter components were identified, namely six flavonoids (rhoifolin, naringin, poncirin, diosmin, didymin, and narirutin) and one phenylpropanoid (purpureaside C). Thus, we proposed a new method for identifying the bitter components in TCM compounds, which provides a theoretical reference for bitter taste inhibition in TCM compounds.

Uncovering the material basis and mechanism of Jianwei Xiaoshi tablet against functional dyspepsia using ultra-high-performance liquid chromatography-mass spectrometry and network pharmacology.

Functional dyspepsia (FD) is a common digestive disease. Jianwei Xiaoshi (JWXS) tablet is composed of Radix Pseudostellariae (TZS), Pericarpium Citri Reticulatae (CP), Rhizoma Dioscoreae (SY), fired Hordei Fructus Germinatus (CMY) and Crataegi Fructus (SZ). It is a commonly used drug in the treatment of FD in China and has good therapeutic effects. However, there is very little research about the substance basis and action mechanism of JWXS tablet. In this research, ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS) and network pharmacology were used to explore the substance basis and action mechanism of the JWXS tablet. Finally, 19, 79, 22, 22 and 39 constituents were identified in the extracts of TZS, CP, SY, CMY and SZ, respectively. Based on these findings, a total of 104 ingredients were identified in JWXS tablet and 29 potentially absorbed ingredients were detected in rat plasma. The results of network pharmacology indicated that the inhibition of gastric acid secretion, the regulation of gastrointestinal motility, inflammation and immune response were the key approaches for treating FD with JWXS tablet. The material basis and potential action mechanism of JWXS tablet in treating FD were comprehensively clarified for the first time. This study will improve our understanding of JWXS tablet.

Quantitation of levetiracetam concentrations in plasma and saliva samples by ultra-performance liquid chromatography-tandem mass spectrometry: Application to therapeutic drug monitoring for pregnant women with epilepsy.

Although levetiracetam (LEV) has favorable linear pharmacokinetic properties, therapeutic drug monitoring (TDM) is necessary for pregnant women with epilepsy. This study aims to build a simple, reliable, and sensitive ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for determining LEV concentrations in plasma and saliva samples, to support the routine TDM of LEV in Chinese pregnant women with epilepsy. The stable isotope-labeled LEV-d6 was used as the internal standard. The extracted samples were analyzed using a UPLC-MS/MS system with positive electrospray ionization. Mobile phase A was water containing 5 mM ammonium acetate and 0.1% formic acid, and phase B was 1:1 methanol-acetonitrile with 0.1% formic acid. The method was validated and utilized to determine LEV concentrations in non-pregnant and pregnant patients with epilepsy. The developed method was validated in both plasma and saliva samples over a concentration range of 0.1-50 µg/mL. The intra- and inter-batch accuracy for LEV ranged from -7.0% to 2.9%, with precisions between 2.7% and 9.3%. In pregnant patients, the mean dose-standardized LEV trough plasma concentrations were significantly lower than those in non-pregnant patients (4.73 ± 2.99 vs. 7.74 ± 3.59 ng/mL per mg/day; P < 0.0001). It is recommended that the TDM of LEV should be routinely performed during the different stages of pregnancy.

Simultaneous determination of five compounds of fried Radix Paeoniae Alba extract in beagle dogs plasma by Ultra Performance Liquid Chromatography Tandem Mass Spectrometry and its application in a pharmacokinetic study.

In this present study, we developed a reliable and simple ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) assay for the simultaneous quantification of paeoniflorin, albiflorin, oxypaeoniflorin, benzoylpaeoniflorin and isomaltopaeoniflorin in beagle dog plasma. We also analyzed the pharmacokinetics of those components after oral administration of fried Radix Paeoniae Alba (FRPA) in beagle dogs. Plasma samples were processed by protein precipitation with methanol. Chromatographic separation was performed with a Waters HSS-T3 C18 column (100 × 2.1 mm, 1.8 µm, kept at 40°C) using multiple reaction monitoring mode. A gradient elution procedure was used with solvent A (0.02% formic acid-water) and solvent B (0.02% formic acid-acetonitrile) as mobile phases. Method validation was performed as US Food and Drug Administration guidelines, and the results met the acceptance criteria. The method we establish in this experiment was successfully applied to the pharmacokinetic study after oral administration of FRPA extract to beagle dogs.

Development of an ultra-high-performance liquid chromatography-tandem mass spectrometry method for the simultaneous determination of crassicauline A, fuziline, karacoline, and songorine in rat plasma and application in their pharmacokinetics.

In this paper, an ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for quantifying the levels of crassicauline A, fuziline, karacoline, and songorine in rat plasma. After processing the rat plasma, the proteins in the plasma were separated by extracting the analytes with acetonitrile-methanol (9:1, v/v). The chromatographic column used was the UPLC HSS T3 column, and the mobile phase (methanol-water with 0.1% formic acid) under a gradient elution profile was used to separate the four compounds, with elution times for each analyte being less than 5 min. Electrospray ionization in positive-ion mode and operating in multiple reaction monitoring mode was used for quantitative analysis. Crassicauline A, fuziline, karacoline, and songorine were administered to 48 rats (n = 6 per group) orally (5 mg/kg) and intravenously (0.5 mg/kg). The standard curves demonstrated excellent linearity in the range of 1-2500 ng/mL, wherein all r values were greater than 0.99. The UPLC-MS/MS method for the determination of crassicauline A, fuziline, karacoline, and songorine in rat plasma was successfully applied in determining their pharmacokinetics parameters, from which their oral bioavailabilities were calculated to be 18.7%, 4.3%, 6.0%, and 8.4%, respectively.

Simultaneous determination of four fungicide residues in figs using liquid chromatography tandem mass spectrometry.

Dissipative behavior and final residue levels of difenoconazole, prochloraz, propiconazole, and pyraclostrobin in figs were investigated using field trials and laboratory assays. A three-factor, three-level orthogonal test was designed to optimize the pretreatment conditions of the method. A method was established using high-performance liquid chromatography tandem mass spectrometry for the determination of difenoconazole, prochloraz, propiconazole, and pyraclostrobin residues in figs. The limit of quantification for all four targets in figs was 0.002 mg/kg. Difenoconazole, prochloraz, propiconazole, and pyraclostrobin are readily digestible pesticides in figs with half-lives of 6.4, 6.2, 4.8, and 7.9 days, respectively. Residues of difenoconazole, prochloraz, propiconazole, and pyraclostrobin in figs were below the European Union established residue levels of 0.1, 0.03, 0.01, and 0.02 mg/kg, respectively, at day 7 after application. Pyraclostrobin, propiconazole, difenoconazole, and prochloraz were applied twice at doses of 75, 125, 150, and 200 mg a.i./kg at 7-day intervals, and the residues of the four fungicides in figs were acceptable 7 days after the last application. Therefore, the safety interval can be set at 7 days for 70% difenoconazole-prochloraz wettable powder and 40% pyraclostrobin-propiconazole aqueous emulsion according to the protocol.

Pharmacokinetics of IMM-H012 in rats using ultra-performance liquid chromatography-tandem mass spectrometry.

The present study examined the pharmacokinetics of IMM-H012 in rat plasma, utilizing ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Internal standard cilostazol was employed, and plasma samples were processed using acetonitrile precipitation. A mobile phase (acetonitrile-0.1% formic acid in water) with gradient elution was used to achieve chromatographic separation using a UPLC BEH C18 column. In multiple reaction monitoring mode, electrospray ionization MS/MS was utilized in positive ionization mode. Based on findings, the lower limit of quantification was 2 ng/mL, and the linearity of IMM-H012 in rat plasma was found to be acceptable within the range of 2-2000 ng/mL (R2 > 0.995). The intra-day and inter-day precision relative standard deviation was less than 14% of IMM-H012 in rat plasma. The matrix effect was within the range of 102%-107%, and the accuracy ranged from 92% to 113%. Pharmacokinetics of IMM-H012 in rats after oral administration were successfully studied using UPLC-MS/MS.

A simple and sensitive ultra-high performance liquid chromatography tandem mass spectrometry method for the quantitative analysis of VX-548 in monkey plasma: Method validation and application to pharmacokinetic study.

VX-548 is an orally active and highly selective NaV 1.8 inhibitor that is undergoing development for the treatment of acute pain. The aim of this study was to develop a liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for the measurement of VX-548 in monkey plasma. VX-548 was extracted from the plasma using acetonitrile-mediated protein precipitation. The quantitative analysis was performed on a Thermo Vantage TSQ mass spectrometer with ibrutinib as an internal standard. Chromatography was performed on a Waters ACQUITY UPLC BEH C18 column with 0.1% aqueous formic acid and acetonitrile as mobile phase. The precursor-to-product ion transitions were m/z 474.2 > 165.0 and m/z 441.2 > 138.1 for VX-548 and internal standard, respectively. This developed method was successfully validated in the concentration range of 1-1000 ng/mL. The calibration curve showed excellent linearity with a correlation coefficient of >0.999. The precision expressed as relative standard deviation (RSD) was <8.4%, whereas the accuracy denoted as relative error (RE) ranged from -5.0% to 9.1%. The mean recovery was >84%. VX-548 was stable in monkey plasma after storage under certain conditions. The validated method was successfully applied to the pharmacokinetic study of VX-548 in monkey plasma after single oral (2 mg/kg) and intravenous (1 mg/kg) administrations.

A sensitive ultra-performance liquid chromatography-tandem mass spectrometry method for the simultaneous quantification of assay and trace-level genotoxic tosylate analogs (methyl and ethyl) in empagliflozin and its tablet dosage forms.

This study performed the simultaneous quantification of assay and two alkyl sulfonate (tosylate) analogs of empagliflozin (EGZ), specifically methyl 4-methyl benzene sulfonate (MMBS) and ethyl 4-methyl benzene sulfonate (EMBS) in EGZ, and its finished dosage form using an accurate and sensitive ultra-performance liquid chromatography-mass spectrometry method. The separation was achieved on a Waters Acquity BEH Shield RP18 (100 × 2.1 mm, 1.7 µm) column in gradient elution mode with 0.1% formic acid and acetonitrile as the mobile phases and a flow rate of 0.5 mL/min. For simultaneous quantification, the multiple reaction monitoring technique was utilized. The procedure was successfully validated in accordance with the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines. The peak areas of both impurities, along with their concentrations, exhibited a good relationship with Pearson's correlation coefficient (R), which was >0.999 in the range of 0.3-6 ppm with an EGZ concentration of 2 mg/mL. The percentage recoveries from the limit of quantitation (LOQ) to 200% to the specification level were in the range of 94.82%-102.92%, whereas the percentage relative standard deviation (%RSD) was <2. Therefore, this method is rapid and accurate to quantify MMBS, EMBS, and EGZ assay simultaneously from the marketed tablet dosage forms of EGZ for commercial release and stability sample testing.

Biosensor-based active ingredient recognition system for screening potential small molecular Severe acute respiratory syndrome coronavirus 2 entry blockers targeting the spike protein from Rugosa rose.

The traditional formulation Hanchuan zupa granules (HCZPs) have been widely used for controlling coronavirus disease 2019 (COVID-19). However, its active components remain unknown. Here, HCZP components targeting the spike receptor-binding domain (S-RBD) of SARS-CoV-2 were investigated using a surface plasmon resonance (SPR) biosensor-based active ingredient recognition system (SPR-AIRS). Recombinant S-RBD proteins were immobilized on the SPR chip by amine coupling for the prescreening of nine HCZP medicinal herbs. Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) identified gallic acid (GA) and methyl gallate (MG) from Rosa rugosa as S-RBD ligands, with KD values of 2.69 and 0.95 µM, respectively, as shown by SPR. Molecular dynamics indicated that GA formed hydrogen bonds with G496, N501, and Y505 of S-RBD, and MG with G496 and Y505, inhibiting S-RBD binding to angiotensin-converting enzyme 2 (ACE2). SPR-based competition analysis verified that both compounds blocked S-RBD and ACE2 binding, and SPR demonstrated that GA and MG bound to ACE2 (KD = 5.10 and 4.05 µM, respectively), suggesting that they blocked the receptor and neutralized SARS-CoV-2. Infection with SARS-CoV-2 pseudovirus showed that GA and MG suppressed viral entry into 293T-ACE2 cells. These S-RBD inhibitors have potential for drug design, while the findings provide a reference on HCZP composition and its use for treating COVID-19.

Network pharmacology study on fermented soybeans for the prevention of Alzheimer's disease in older individuals.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by the disruption of synaptic communication among millions of neurons. Recent research has highlighted the potential therapeutic effectiveness of natural polyphenolic compounds in addressing AD. Soybeans are abundant in polyphenols, and their polyphenolic composition undergoes significant alteration through fermentation by Eurotium cristatum. Through comprehensive database searches, we identified active components within fermented soybean polyphenols and genes associated with AD. Subsequently, we utilized Venn diagrams to analyze the overlap between AD-related genes and these components. Furthermore, we visualized the network between intersecting targets and proteins using Cytoscape software. The anti-AD effects of soybeans were further explored through comprehensive analysis, including protein-protein interaction analysis, pathway enrichment analysis, and molecular docking studies. Our investigation unveiled 6-hydroxydaidzein as a major component of fermented soybean polyphenols, shedding light on its potential therapeutic significance in combating AD. The intersection between target proteins of fermented soybeans and disease-related targets in AD comprised 34 genes. Protein-protein interaction analysis highlighted key potential targets, including glyceraldehyde-3-phosphate dehydrogenase (GAPDH), glycogen synthase kinase 3 beta (GSK3B), amyloid precursor protein (APP), cyclin-dependent kinase 5 (CDK5), and beta-site APP cleaving enzyme 1 (BACE1). Molecular docking results demonstrated a robust binding effect between major components from fermented soybeans and the aforesaid key targets implicated in AD treatment. These findings suggest that fermented soybeans demonstrate a degree of efficacy and present promising prospects in the prevention of AD.