Ultra-high Performance Liquid Chromatography Research Articles

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

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

Amino acid metabolomics and machine learning for assessment of post-hepatectomy liver regeneration

ObjectiveAmino acid (AA) metabolism plays a vital role in liver regeneration. However, its measuring utility for post-hepatectomy liver regeneration under different conditions remains unclear. We aimed to combine machine learning (ML) models with AA metabolomics to assess liver regeneration in health and non-alcoholic steatohepatitis (NASH).MethodsThe liver index (liver weight/body weight) was calculated following 70% hepatectomy in healthy and NASH mice. The serum levels of 39 amino acids were measured using ultra-high performance liquid chromatography–tandem mass spectrometry analysis. We used orthogonal partial least squares discriminant analysis to determine differential AAs and disturbed metabolic pathways during liver regeneration. The SHapley Additive exPlanations algorithm was performed to identify potential AA signatures, and five ML models including least absolute shrinkage and selection operator, random forest, K-nearest neighbor (KNN), support vector regression, and extreme gradient boosting were utilized to assess the liver index.ResultsEleven and twenty-two differential AAs were identified in the healthy and NASH groups, respectively. Among these metabolites, arginine and proline metabolism were commonly disturbed metabolic pathways related to liver regeneration in both groups. Five AA signatures were identified, including hydroxylysine, L-serine, 3-methylhistidine, L-tyrosine, and homocitrulline in healthy group, and L-arginine, 2-aminobutyric acid, sarcosine, beta-alanine, and L-cysteine in NASH group. The KNN model demonstrated the best evaluation performance with mean absolute error, root mean square error, and coefficient of determination values of 0.0037, 0.0047, 0.79 and 0.0028, 0.0034, 0.71 for the healthy and NASH groups, respectively.ConclusionThe KNN model based on five AA signatures performed best, which suggests that it may be a valuable tool for assessing post-hepatectomy liver regeneration in health and NASH.

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

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

#1554 The association between gut-derived metabolites and biomarkers of renal and cerebro-vascular damage in type 2 diabetes mellitus patients

Abstract Background and Aims Due to its numerous complications, type 2 diabetes mellitus (T2DM) has a major impact on the global economic burden and overall mortality. This condition modifies the metabolic microenvironment in targeted organs, such as the kidney and the brain, by its hyperglycemic nature. Gut microbiota seems to have significant interference with the renal-cerebral axis, especially in a dysbiosis state. The aim of the study was to quantify gut derived metabolites by metabolomic techniques and to evaluate their association with markers of endothelial, podocyte and proximal tubule damage and with cerebro-vascular hemodynamic indices. Method The metabolomic profiling was realized on serum and urine samples originated from 90 T2DM patients, divided into three subgroups, such as the following: 30 normal to mildly-, 30 moderately-, and 30 severely increased albuminuria, respectively, and 20 healthy subjects. The samples were examined by using untargeted and targeted ultra-high performance liquid chromatography coupled with electrospray-ionization quadroupole time-of-flight mass spectrometry (UHPLC-QTOF-ESI+-MS), in order to obtain the metabolic profile. The markers of renal damage such as synaptopodin (SP), podocalyxin (PD), N-acetyl-β-D-glucosaminidase (NAG), kidney injury molecule 1 (KIM-1), monocyte chemotactic protein 1 (MCP-1), and intercellular adhesion molecule 1 (ICAM-1) were assessed by ELISA technique. The hemodynamic cerebro-vascular indices were obtained by high resolution Doppler ultrasound of common carotid arteries (CCAs), internal carotid arteries (ICAs), and middle cerebral arteries (MCAs), bilaterally. The correlations between the metabolites, the markers of renal damage, and neurosonological indices were realized by univariable and multivariable linear regression analyses. Results UHPLC-QTOF-ESI+-MS targeted analysis and subsequent statistical assessments revealed a subset of metabolites with a specific pattern for the normal to mildly increased albuminuria subgroup. The metabolites identified as significant were, in serum: arginine (sArg), hippuric acid (sHA), indoxyl sulfate (sIS), butenoylcarnitine (sBCA), sorbitol (sSorb); and in urine, arginine (uArg), butenoylcarnitine (uBCA), indoxyl sulfate (uIS) and p-cresyl sulfate (uPCS). The univariable linear regression analysis revealed that sArg correlated positively with the breath-holding index (BHI) and negatively with intima media thickness (IMT) in ACI, MCP-1 and ICAM-1; sIS, sSorb, and sBCA correlated inversely with these parametes. The multivariable linear regression analysis displayed the specific correlations between metabolites, markers of endothelial dysfunction, and neurosonological indices, such as follows: sArg correlated with IMT and ICAM-1; sIS followed a predictive pattern along with resistance index (RI) in ACIs and ICAM-1; sBCA correlated with IMT and MCP-1 and sSorb correlated with ICAM-1 and BHI. The urine metabolites were correlated with markers of podocyte and proximal tubule dysfunction: uIS and uBCA were correlated with PD and urinary albumin to-creatinin ratio (uACR), and uPCR correlated with KIM-1 and uACR. Conclusion This study revealed a set of metabolites potentially derived from the intestinal microflora which may act as biomarkers for the early detection of both CMA and DKD in T2DM patients. SArg, sIS and, sBCA are indicators of renal endothelial dysfunction. Moreover, sArg and sIS reflect incipient common and internal carotid artery atherosclerosis, suggesting vascular remodeling at these levels. SSorb correlated with BHI, indicating blood-brain barrier dysfunction and CMA development. In urine, uBCA and uIS are indicators of podocytopathy, whereas uPCS is associated with proximal tubule damage in incipient DKD.

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.

Widely targeted metabolomics analysis of Sanghuangporus vaninii mycelia and fruiting bodies at different harvest stages

Sanghuangprous vaninii is a medicinal macrofungus cultivated extensively in China. Both the mycelia and fruiting bodies of S. vaninii have remarkable therapeutic properties, but it remains unclear whether the mycelia may serve as a substitute for the fruiting bodies. Furthermore, S. vaninii is a perennial fungus with therapeutic components that vary significantly depending on the growing year of the fruiting bodies. Hence, it is critical to select an appropriate harvest stage for S. vaninii fruiting bodies for a specific purpose. With the aid of Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), metabolomics based on ultra-high performance liquid chromatography coupled to triple quadrupole mass spectrometry (UHPLC-QQQ-MS) was used to preliminarily determine 81 key active metabolites and 157 active pharmaceutical metabolites in S. vaninii responsible for resistance to the six major diseases. To evaluate the substitutability of the mycelia and fruiting bodies of S. vaninii and to select an appropriate harvest stage for the fruiting bodies of S. vaninii, we analyzed the metabolite differences, especially active metabolite differences, among the mycelia and fruiting bodies during three different harvest stages (1-year-old, 2-year-old, and 3-year-old). Moreover, we also determined the most prominent and crucial metabolites in each sample of S. vaninii. These results suggested that the mycelia show promise as a substitute for the fruiting bodies of S. vaninii and that extending the growth year does not necessarily lead to higher accumulation levels of active metabolites in the S. vaninii fruiting bodies. This study provided a theoretical basis for developing and using S. vaninii.

Rapid Classification and Identification of Chemical Compounds and Semi-Quantitative Metabolism of Huangkui Capsules and the Protective Effects of Its Quercetin Derivatives against Tacrolimus-induced HK-cell Reduction

Abstract Objective: The study aimed to establish an effective strategy for systematically characterizing and verifying compounds in Huangkui capsules (HKCs). Materials and Methods: An ultrahigh-performance liquid chromatography quadrupole time-of-flight mass spectrometry (MS) method was effectively established and utilized for the chemical compound characterization in HKC, with the support of MS-DIAL, MS-FINDER, and Global Natural Product Social Molecular Network. Multiple rat samples were analyzed after the oral administration. Metabolites were identified based on specific cleavage behaviors, and metabolic pathways were predicted. Semi-quantitative analysis of the metabolome profiles was conducted using post-data processing. High concentrations in vivo were investigated for their role in tacrolimus-induced death of HK-2 cells. Results: In total, 129 compounds were identified in HKC, of which 74 were reported for the first time. In this study, we successfully identified and uncovered 19 prototypes and 123 metabolites from the biosamples. The concentrations of glucuronidation and methylation metabolites of quercetin were the highest in the kidney and intestinal tissues. In contrast, significant glucuronidation of quercetin metabolites was observed with high blood concentrations. Notably, quercetin glucuronidation and methylation metabolites protected HK-cell against tacrolimus-induced injury in a dose-dependent manner. Conclusion: This study successfully established a reliable and efficient strategy for comprehensive characterization of traditional Chinese medicine compounds. This strategy harnessed the power of various intelligent postprocessing technologies to provide a more thorough understanding of active components and their metabolic transformations in the body. These results suggest that quercetin metabolites should be evaluated for their protective capacity against kidney disease.

Rapid chemical characterization and pharmacological mechanism of Fining Granules in the treatment of chronic bronchitis based on UHPLC–Q-exactive orbitrap mass spectrometer and network pharmacology

BackgroundSenecio cannabifolius Less. is a perennial herb belonging to the Compositae family that has been used in traditional medicine as an antitussive and expectorant for treating chronic bronchitis and acute respiratory infections. Traditionally, Feining Granules are prepared from water extracts of the raw plant material. However, the chemical composition and pharmacological mechanisms of Feining Granules have not been thoroughly investigated. MethodsA systematic strategy for the rapid detection and identification of the constituents of Feining Granules was developed using ultrahigh-performance liquid chromatography–quadrupole-exactive orbitrap mass spectrometry (MS) with parallel reaction monitoring. ResultsOverall, 162 compounds, including flavonoids, alkaloids, organic acids, and others, were identified unambiguously and tentatively by comparing the retention times and MS fragmentation with reference standards and literature data. Ninety-nine of these were reported for the first time to the best of our knowledge. Network pharmacology suggests that Feining Granules can be used to treat chronic bronchitis as they contain active components associated with the ALB, VEGFA, and SRC target genes influenced by HIF-1, VEGF, and other signaling pathways. ConclusionThese results provide information that can help understand the effective substances of S. cannabifolius Less. and improve quality control.

Dissipation pattern of tetraniliprole in/on green chilies.

Field and lab experiments explored tetraniliprole dissipation in chili plants. A supervised trial in Devarayapuram village, Coimbatore, assessed the CO2 chili variety (December-March 2018-2019). Using the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method and ultra-high-performance liquid chromatography (UHPLC), samples were collected up to 15d post-application. Initial tetraniliprole deposits on chili fruits, 1-h post-spray, were 0.898 and 1.271 μg g-1 at single and double doses. Over 80% dissipated within 5d, reaching below detection limits by day 7 and 10 for single and double doses, respectively. Transformation analysis favored first-order kinetics. Tetraniliprole half-life on chili fruit was 1.49 and 1.53d at recommended and double doses. The safe waiting period was 4.16 and 5.04d for 60 and 120 g a.i ha-1. This study provides insights into tetraniliprole dynamics in chili plants, crucial for effective pesticide management.

Spectrum-effect relationship between HPLC fingerprints and antioxidant activity of Qi-Fu-Yin based on multiple statistical correlation analysis.

Qi-Fu-Yin has been used to treat Alzheimer's disease (AD) in China. Oxidative stress has been recognized as a factor in AD progress. To date, there is no quality control method to ensure batch-to-batch consistency of Qi-Fu-Yin, and the potential antioxidant compounds in Qi-Fu-Yin remain uncertain. The aim of this study is to identify the potential antioxidant compounds of Qi-Fu-Yin and establish quality control standards for Qi-Fu-Yin. High-performance liquid chromatography was used to establish and quantify the fingerprints of Qi-Fu-Yin from various batches. Ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UHPLC-Q-TOF/MS) was used to identify the common peaks. Bivariate correlation analysis, partial least squares regression analysis, and gray correlation analysis were used to establish the spectrum-effect relationship. Forty-nine common peaks were determined through the establishment of fingerprints. Among them, 35 common peaks were preliminarily characterized. The multiple statistical correlation analysis methods identified six compounds as potential antioxidant constituents of Qi-Fu-Yin, and their antioxidant activities were validated in vitro. All six antioxidant compounds derived from two herbs. Therefore, three chemical index compounds derived from other three herbs were added to the quantitative analysis, while for two herbs, no peaks could be included. Eventually, six antioxidant constituents and three index compounds were quantitatively determined to provide a relatively comprehensive quality control for Qi-Fu-Yin. The study elucidated the antioxidant substance basis of Qi-Fu-Yin and provided a relatively comprehensive approach for the assay of Qi-Fu-Yin, which is a promising advance in the quality control of Qi-Fu-Yin.

Identification of volatile and non-volatile migrants released during sous vide cooking by UPLC-IMS-QTOF and DI-SPME-GC-MS using a design of experiments approach

The rise of new culinary advances combined with science has made it possible to find new optimum methods of cooking, such as vacuum cooking (Sous Vide), that allow achieving pleasant textures, preserving the genuine nature of the food and also its original flavour. Sous Vide involves the direct contact of plastic materials with food during cooking, causing the possible release of chemical compounds that may alter the properties of the food and pose a risk to human health. In this work, the migration kinetics that takes place during this cooking process have been estimated thanks to a design of experiments (DoE). DoE has been applied to 4 samples of vacuum cooking bags containing 3 food simulants (ethanol 10%, acetic acid 3% and isooctane) under typical cooking conditions of the culinary technique. The study also allowed the identification of the main volatile and non-volatile migrants that can be transferred from this particular packaging. Twenty-nine non-volatile species were identified by ultra-high performance liquid chromatography coupled to a quadrupole-time-of-flight ion-mobility separation mass spectrometer (UPLC-IMS-QTOF) and sixty-four volatile species were identified by solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). Furthermore, a comprehensive literature analysis was conducted to explore the applications, origins, and potential toxicity of these compounds.

Seasonal and Morphology Effects on Bioactive Compounds, Antioxidant Capacity, and Sugars Profile of Black Carrot (Daucus carota ssp. sativus var. atrorubens Alef.).

Black carrot (Daucus carota ssp. sativus var. atrorubens Alef.) is widely recognized for its bioactive compounds and antioxidant properties. The black carrot of Cuevas Bajas (Málaga) is a local variety characterized by a black/purple core, which differs from other black carrot varieties. Therefore, this autochthonous variety was characterized according to the root size and the harvesting season by means of a study of its antioxidant capacity analyzed by three methods, its total carotenoids content, and its sugars and phenolic compounds profile by ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-MS). A total of 20 polyphenolic compounds were quantified in 144 samples analyzed. The anthocyanidins group was observed to be the most abundant, followed by the hydroxycinnamic acids group. Moreover, pelargonidin 3-sambubioside was observed in black carrot for the first time. The medium-sized carrots presented the highest content of phenolic compounds, largely due to their significantly higher anthocyanidins content. Comparatively, the small carrots showed a higher content of simple sugars than the large ones. Regarding the influence of season, significantly higher quantities of glucose and fructose were observed in the late-season carrots, while sucrose was the main sugar in early-season samples. No significant differences were observed in the total carotenoid content of black carrot.

Cilentan Cichorium intybus L. organs: UHPLC-QqTOF-MS/MS analysis for new antioxidant scenario, exploitable locally and beyond

In the framework aimed at evaluating the close link between the chemical composition of poorly explored organs of local edible medicinal plants in the Cilento region (Southern Italy) and their recovery for new health products, Cichorium intybus L. was of interest. Ultra-High Performance Liquid Chromatography Quadrupole-Time-Of-Flight tandem Mass Spectrometry (UHPLC-QqTOF-MS/MS) investigation revealed that sesquiterpene lactones characterized roots and stems, while hydroxycinnamic derivatives accumulated in florets, bracts, and leaves. Florets diverged for anthocyanin derivatives, while roots differed by low flavonoid content. Despite shared phytochemical constituents, their ratio was responsible for different antioxidant responses. Notably, extracts, particularly rich in hydroxycinnamoyl derivatives, showed protective effects against oxidative stress induced by hydrogen peroxide in SH-SY5Y and HaCaT cell lines. The wound healing assay revealed marked inhibition of SH-SY5Y cell migration, avoiding wound closure. Overall, the research encourages the use of different organs from Cilentan wild chicory to obtain antioxidant safe and consumer-guaranteed products.

Evaluation of pesticide residues in rice marketed in Cape Verde by QuEChERS-LC/GC-MS analysis

In this work, a multiresidue pesticide analysis using both gas chromatography and ultra-high performance liquid chromatography coupled to mass spectrometry systems has been conducted to determine 151 pesticides in rice samples consumed by the population of Cape Verde. The extraction and clean-up procedures were carried out by the QuEChERS method. The validation of both methodologies achieved determination coefficients higher than 0.9902 in matrix-matched calibration, relative recovery values in the range 58–120% with relative standard deviation lower than 20%, and limits of quantification of the method in the range 0.008–0.017 mg/kg, which agreed with the legal limits established by both EU regulations and the Codex Alimentarius guidelines. Among the total of 98 rice samples analysed, 91 samples were contaminated by pesticides at concentrations up to 18.3 mg/kg, with pirimiphos-methyl, propiconazole, tebuconazole, and imidacloprid being the most frequently detected. Following EU regulations, 14 non-compliances were found in 13 samples, whereas only one non-compliance was identified according to the Codex. Besides, a risk assessment based on the dietary exposure was performed for the pesticides found in the analysed rice samples. The results showed the need to carry out stricter controls to ensure the security of food agricultural products to protect consumers’ health.

Image analysis and polyphenol profiling unveil red-flesh apple phenotype complexity.

The genetic basis of colour development in red-flesh apples (Malus domestica Borkh) has been widely characterised; however, current models do not explain the observed variations in red pigmentation intensity and distribution. Available methods to evaluate the red-flesh trait rely on the estimation of an average overall colour using a discrete class notation index. However, colour variations among red-flesh cultivars are continuous while development of red colour is non-homogeneous and genotype-dependent. A robust estimation of red-flesh colour intensity and distribution is essential to fully capture the diversity among genotypes and provide a basis to enable identification of loci influencing the red-flesh trait. In this study, we developed a multivariable approach to evaluate the red-flesh trait in apple. This method was implemented to study the phenotypic diversity in a segregating hybrid F1 family (91 genotypes). We developed a Python pipeline based on image and colour analysis to quantitatively dissect the red-flesh pigmentation from RGB (Red Green Blue) images and compared the efficiency of RGB and CIEL*a*b* colour spaces in discriminating genotypes previously classified with a visual notation. Chemical destructive methods, including targeted-metabolite analysis using ultra-high performance liquid chromatography with ultraviolet detection (UPLC-UV), were performed to quantify major phenolic compounds in fruits' flesh, as well as pH and water contents. Multivariate analyses were performed to study covariations of biochemical factors in relation to colour expression in CIEL*a*b* colour space. Our results indicate that anthocyanin, flavonol and flavanol concentrations, as well as pH, are closely related to flesh pigmentation in apple. Extraction of colour descriptors combined to chemical analyses helped in discriminating genotypes in relation to their flesh colour. These results suggest that the red-flesh trait in apple is a complex trait associated with several biochemical factors.

Efficient Quality Control of Peptide Pools by UHPLC and Simultaneous UV and HRMS Detection

Peptide pools consist of short amino acid sequences and have proven to be versatile tools in various research areas in immunology and clinical applications. They are commercially available in many different compositions and variants. However, unlike other reagents that consist of only one or a few compounds, peptide pools are highly complex products which makes their quality control a major challenge. Quantitative peptide analysis usually requires sophisticated methods, in most cases isotope-labeled standards and reference materials. Usually, this would be prohibitively laborious and expensive. Therefore, an approach is needed to provide a practical and feasible method for quality control of peptide pools. With insufficient quality control, the use of such products could lead to incorrect experimental results, worsening the well-known reproducibility crisis in the biomedical sciences. Here we propose the use of ultra-high performance liquid chromatography (UHPLC) with two detectors, a standard UV detector at 214 nm for quantitative analysis and a high-resolution mass spectrometer (HRMS) for identity confirmation. To be cost-efficient and fast, quantification and identification are performed in one chromatographic run. An optimized protocol is shown, and different peak integration methods are compared and discussed. This work was performed using a peptide pool known as CEF advanced, which consists of 32 peptides derived from cytomegalovirus (CMV), Epstein–Barr virus (EBV) and influenza virus, ranging from 8 to 12 amino acids in length.

Development and validation of stability indicating ultra‐high‐performance liquid chromatographic method for assay and impurities of mexiletine hydrochloride and mexiletine hydrochloride capsules

AbstractMexiletine (MEX) is an antiarrhythmic drug used to treat acute and chronic ventricular arrhythmias. A simple isocratic, rapid, specific, stability‐indicating, and sensitive reverse‐phase ultra‐high‐performance liquid chromatography (UHPLC) method was developed and successfully validated to quantify the assay and impurities of MEX hydrochloride. The new UHPLC method showed the optimum separation of MEX and its seven impurities in 20 min by using sodium acetate buffer (0.14 mM) with 0.3% of glacial acetic acid (pH 4.8) and methanol in the ratio of 40:60 (v/v) as mobile phase. The method used an Acquity HSS T3 (100 × 3.0 mm, 1.8 µm) chromatographic column at a 0.2 mL/min flow rate. The injection volume is 2 µL, and 254 nm is the detection wavelength. Note that, 25°C is the column oven temperature. The method is linear over the concentration range of the quantification limit (0.03%) to 150% (0.3%) of the specification level (0.2%) for the impurities and 50%–150% for the assay method. The quality control lab of bulk drugs and finished dosage form successfully applied the new UHPLC method for quantification of assay and impurities of MEX hydrochloride.

Chemical characterization and comparative analysis of different parts of Cocculus orbiculatus through UHPLC-Q-TOF-MS.

Cocculus orbiculatus (L.) DC. (C. orbiculatus) is a medicinal herb valued for its dried roots with anti-inflammatory, analgesic, diuretic, and other therapeutic properties. Despite its traditional applications, chemical investigations into C. orbiculatus remain limited, focusing predominantly on alkaloids and flavonoids. Furthermore, the therapeutic use of C. orbiculatus predominantly focuses on the roots, leaving the stems, a significant portion of the plant, underutilized. This study employed ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) with in-house and online databases for comprehensive identification of components in various plant parts. Subsequently, untargeted metabolomics was employed to analyze differences in components across different harvest periods and plant sections of C. orbiculatus, aiming to screen for distinct components in different parts of the plant. Finally, metabolomic analysis of the roots and stems, which contribute significantly to the plant's weight, was conducted using chemometrics, including principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), orthogonal partial least squares discriminant analysis (OPLS-DA), and heatmaps. A total of 113 components, including alkaloids, flavonoids, and organic acids, were annotated across the root, stem, leaf, flower, and fruit, along with numerous previously unreported compounds. Metabolomic analyses revealed substantial differences in components between the root and stem compared to the leaf, flower, and fruit during the same harvest period. PLS-DA and OPLS-DA annotated 10 differentiating components (VIP > 1.5, P < 0.05, FC > 2 or FC < 0.67), with 5 unique to the root and stem, exhibiting lower mass spectrometric responses. This study provided the first characterization of 113 chemical constituents in different parts of C. orbiculatus, laying the groundwork for pharmacological research and advocating for the enhanced utilization of its stem.

Quality markers of Polygala fallax Hemsl decoction based on qualitative and quantitative analysis combined with network pharmacology and chemometric analysis.

Polygala fallax Hemsl (PFH) is a widely used herbal medicine in Guangxi, China. At present, research on PFH mainly focuses on extraction technology and cultivation, lacking quality control standards for systematic evaluation. The study aimed to assess the quality of PFH from different sources and to predict markers that would help assess quality. Fingerprinting of 15 batches of PFH samples was performed by ultra-high performance liquid chromatography (UPLC) and similarity was assessed using hierarchical cluster analysis (HCA), principal component analysis (PCA), and orthogonal partial least squares discrimination (OPLS-DA). Differential components were screened by mathematical analysis, and a "component-target-pathway" network map was constructed in combination with network pharmacology, quality markers (Q-markers) of PFH were predicted, and quantitative analysis was performed. Fifteen batches were fingerprinted for PFH, with 11 common peaks, and peak 5 was identified as 4-hydroxybenzoic acid, which was generally consistent with the results of HCA, PCA, and OPLS-DA. Network pharmacology screened 18 potential compounds, 45 core targets, and 20 key pathways, integrating fingerprinting, pattern recognition, and network pharmacology methods. One of the potential Q-markers that can identify the principle of testability, efficacy, and specificity is 4-hydroxybenzoic acid, whose content ranges from 0.0188 to 1.4517 mg/g. The potential Q-markers of PFH were predicted by integrating fingerprinting, pattern recognition, and network pharmacological analysis, which provided a scientific basis for the overall control and evaluation of the quality of PFH and a theoretical reference for the study of the quality standard of multi-base traditional Chinese medicine.

Wine- and stir-frying processing of Cuscutae Semen enhance its ability to alleviate oxidative stress and apoptosis via the Keap 1-Nrf2/HO-1 and PI3K/AKT pathways in H2O2-challenged KGN human granulosa cell line

BackgroundCuscutae Semen (CS) has been prescribed in traditional Chinese medicine (TCM) for millennia as an aging inhibitor, an anti-inflammatory agent, a pain reliever, and an aphrodisiac. Its three main forms include crude Cuscutae Semen (CCS), wine-processed CS (WCS), and stir-frying-processed CS (SFCS). Premature ovarian insufficiency (POI) is a globally occurring medical condition. The present work sought a highly efficacious multi-target therapeutic approach against POI with minimal side effects. Finally, it analyzed the relative differences among CCS, WCS and SFCS in terms of their therapeutic efficacy and modes of action against H2O2-challenged KGN human granulosa cell line.MethodsIn this study, ultrahigh-performance liquid chromatography (UPLC)-Q-ExactiveTM Orbitrap-mass spectrometry (MS), oxidative stress indices, reactive oxygen species (ROS), Mitochondrial membrane potential (MMP), real-time PCR, Western blotting, and molecular docking were used to investigate the protective effect of CCS, WCS and SFCS on KGN cells oxidative stress and apoptosis mechanisms.ResultsThe results confirmed that pretreatment with CCS, WCS and SFCS reduced H2O2-induced oxidative damage, accompanied by declining ROS levels and malondialdehyde (MDA) accumulation in the KGN cells. CCS, WCS and SFCS upregulated the expression of antioxidative levels (GSH, GSH/GSSG ratio, SOD, T-AOC),mitochondrial membrane potential (MMP) and the relative mRNA(Nrf2, Keap1, NQO-1, HO-1, SOD-1, CAT). They inhibited apoptosis by upregulating Bcl-2, downregulating Bax, cleaved caspase-9, and cleaved caspase-3, and lowering the Bax/Bcl-2 ratio. They also exerted antioxidant efficacy by partially activating the PI3K/Akt and Keap1-Nrf2/HO-1 signaling pathways.ConclusionsThe results of the present work demonstrated the inhibitory efficacy of CCS, WCS and SFCS against H2O2-induced oxidative stress and apoptosis in KGN cells and showed that the associated mechanisms included Keap1-Nrf2/HO-1 activation, P-PI3K upregulation, and P-Akt-mediated PI3K-Akt pathway induction.