OBJECTIVES: To establish a method for the detection of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS). METHODS: The blood samples were treated with 1-butyl-3-methylimidazolium hexafluorophosphate as an extraction solvent. The samples were extracted by ultrasound-assisted extraction and separated by ZORBAX Eclipse Plus C18, 95Å column. The mobile phase A aqueous solution containing 0.1% formic acid and 10 mmol/L ammonium acetate, and mobile phase B mixed organic solvent containing acetonitrile/methanol (V_acetonitrile∶V_methanol=2∶3) were used for gradient elution at the flow rate of 1.00 mL/min. An electrospray ion source in positive mode was used for detection in the multiple reaction monitoring. RESULTS: The linearities of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples were good within the corresponding range, with correlation coefficients (r) greater than 0.995 6. The limits of detection were 3.00, 0.40 and 1.30 ng/mL, respectively. The limit of quantitation were 8.00, 1.00 and 5.00 ng/mL, respectively. The extraction recoveries ranged from 76.00% to 106.44%. The relative standard deviations of the intra-day and inter-day precisions were less than 16%. Carbamazepine and its main metabolite 10,11-dihydro-10,11-epoxycarbamazepine were detected in blood samples of death cases with a mass concentration of 2.71 μg/mL and 252.14 ng/mL, respectively. CONCLUSIONS This method has high sensitivity and good selectivity, which is suitable for the detection of carbamazepine and its metabolites in blood samples, and can be used for carbamazepine-related forensic identifications.
Chromatography, Liquid/methods* ; Tandem Mass Spectrometry ; Methanol ; Carbamazepine/analysis* ; Benzodiazepines/analysis* ; Solvents ; Chromatography, High Pressure Liquid ; Solid Phase Extraction

Many natural products can be bio-converted by the gut microbiota to influence pertinent efficiency. Ginsenoside compound K (GCK) is a potential anti-type 2 diabetes (T2D) saponin, which is mainly bio-transformed into protopanaxadiol (PPD) by the gut microbiota. Studies have shown that the gut microbiota between diabetic patients and healthy subjects are significantly different. Herein, we aimed to characterize the biotransformation of GCK mediated by the gut microbiota from diabetic patients and healthy subjects. Based on 16S rRNA gene sequencing, the results indicated the bacterial profiles were considerably different between the two groups, especially Alistipes and Parabacteroides that increased in healthy subjects. The quantitative analysis of GCK and PPD showed that gut microbiota from the diabetic patients metabolized GCK slower than healthy subjects through liquid chromatography tandem mass spectrometry (LC-MS/MS). The selected strain A. finegoldii and P. merdae exhibited a different metabolic capability of GCK. In conclusion, the different biotransformation capacity for GCK may impact its anti-diabetic potency.
Humans ; Gastrointestinal Microbiome/genetics* ; Chromatography, Liquid/methods* ; Healthy Volunteers ; RNA, Ribosomal, 16S ; Feces/microbiology* ; Tandem Mass Spectrometry ; Biotransformation ; Diabetes Mellitus, Type 2/drug therapy*

From the fungus Trichoderma sp., we isolated seven novel 18-residue peptaibols, neoatroviridins E-K (1-7), and six new 14-residue peptaibols, harzianins NPDG J-O (8-13). Additionally, four previously characterized 18-residue peptaibols neoatroviridins A-D (14-17) were also identified. The structural configurations of the newly identified peptaibols (1-13) were determined by comprehensive nuclear magnetic resonance (NMR) and high-resolution electrospray ionization tandem mass spectrometry (HR-ESI-MS/MS) data. Their absolute configurations were further determined using Marfey's method. Notably, compounds 12 and 13 represent the first 14-residue peptaibols containing an acidic amino acid residue. In antimicrobial assessments, all 18-residue peptaibols (1-7, 14-17) exhibited moderate inhibitory activities against Staphylococcus aureus 209P, with minimum inhibitory concentration (MIC) values ranging from 8-32 μg·mL^-1. Moreover, compound 9 exhibited moderate inhibitory effect on Candida albicans FIM709, with a MIC value of 16 μg·mL^-1.
Peptaibols/chemistry* ; Trichoderma/metabolism* ; Tandem Mass Spectrometry/methods* ; Anti-Infective Agents/pharmacology* ; Spectrometry, Mass, Electrospray Ionization/methods*

Data-independent acquisition (DIA) is a high-throughput, unbiased mass spectrometry data acquisition method which has good quantitative reproducibility and is friendly to low-abundance proteins. It becomes the preferred choice for clinical proteomic studies especially for large cohort studies in recent years. The mass-spectrometry (MS)/MS spectra generated by DIA is usually heavily mixed with fragment ion information of multiple peptides, which makes the protein identification and quantification more difficult. Currently, DIA data analysis methods fall into two main categories, namely peptide-centric and spectrum-centric. The peptide-centric strategy is more sensitive for identification and more accurate for quantification. Thus, it has become the mainstream strategy for DIA data analysis, which includes four key steps: building a spectral library, extracting ion chromatogram, feature scoring and statistical quality control. This work reviews the peptide-centric DIA data analysis procedure, introduces the corresponding algorithms and software tools, and summarizes the improvements for the existing algorithms. Finally, the future development directions are discussed.
Humans ; Proteomics/methods* ; Reproducibility of Results ; Peptides/chemistry* ; Software ; Algorithms ; Tandem Mass Spectrometry/methods* ; Proteome/analysis*

To explore the resource components and availability of different parts of Panax quinquefolium in Shandong province, the paper employed the non-targeted metabolomics technology based on ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) to analyze the metabolites and their metabolic pathways in the root, fibril, stem, and leaf of P. quinquefolium. The content of seven ginsenosides and polysaccharides in different parts was determined by high performance liquid chromatography(HPLC) and ultraviolet-visible spectrophotometry(UV-Vis). The results showed that the metabolites were mainly sugars, glycosides, organic acids, amino acids and their derivatives, terpenoids, etc. The total abundance of metabolites followed the trend of leaf > root > fibril > stem. Most of the differential metabolites were concentrated in phenylpropane biosynthesis, flavonoid biosynthesis, citric acid cycle, and amino acid biosynthesis. The leaf contained high levels of sugars, glycosides, amino acids and their derivatives, and flavonoids; the root was rich in terpenoids, volatile oils, vitamins, and lignin; the fibril contained rich organic acids; and the stem had high content of nucleotides and their derivatives. The content of ginsenosides Re and Rb_1 was significantly higher in the root; the content of ginsenosides Rg_1, Rg_2, Rd, F_(11), and polysaccharide was significantly higher in the leaf; and the content of ginsenoside Rb_2 was significantly higher in the stem. We analyzed the resource components and availability of different parts of P. quinquefolium, aiming to provide basic information for the comprehensive development and utilization of P. quinquefolium resources in Shandong province.
Ginsenosides/analysis* ; Plant Roots/chemistry* ; Tandem Mass Spectrometry/methods* ; Panax/chemistry* ; Chromatography, Liquid ; Chromatography, High Pressure Liquid/methods* ; Sugars

Prunellae Spica is the dried spica of Prunella vulgaris belonging to Labiatae and it is widely used in pharmaceutical and general health fields. As a traditional Chinese medicine cultivated on a large scale, it produces a large amount of non-medicinal parts, which are discarded because they are not effectively used. To analyze the chemical constituents in the different samples from spica, seed, stem, and leaf of P. vulgaris, and explore the application value and development prospect of these parts, this study used ultrahigh performance liquid chromatography-tandem quadrupoles time of flight mass spectrometry(UPLC-Q-TOF-MS/MS) to detect chemical constituents in different parts of P. vulgaris. As a result, 117 compounds were detected. Among them, 87 compounds were identified, including 32 phenolic acids, 8 flavonoids, and 45 triterpenoid saponins. Some new triterpenoid saponins containing the sugar chain with 4-6 sugar units were found. Further, multivariate statistical analysis was conducted on BPI chromatographic peaks of multiple batches of different parts, and the results showed that spica had the most abundant chemical constituents, including salviaflaside and linolenic acid highly contained in the seed and phenolic acids, flavonoids, and triterpenoid saponins in the stem and leaf. In general, the constituents in the spica were composed of those in the seed, stem, and leaf. UPLC was used to determine the content of 6 phenolic acids(danshensu, protocatechuic acid, protocatechuic aldehyde, caffeic acid, salviaflaside, and rosmarinic acid) in different parts. The content of other phenolic acids in the seed was generally lower than that in the spica except that of salviaflaside. The content of salviaflaside in the spica was higher than that in the stem and leaf, but the content of other phenolic acids in the spica was not significantly different from that in the stem. The content of protocatechuic aldehyde and caffeic acid in the spica was lower than that in the leaf. DPPH free radical scavenging method was used to detect the antioxidant activity of four parts, and there was no significant difference in the antioxidant activity between the spica and the stem and leaf, but that was significantly higher than the seed. Moreover, the antioxidant activity of these parts was correlated with the content of total phenolic acids. Based on the above findings, the stem and leaf of P. vulgaris have potential application value. Considering the traditional medication rule, it is feasible to use the whole plant as a medicine. Alternatively, salviaflaside, occurring in the seed, can be used as a marker compound for the quality evaluation of Prunellae Spica, if only using spica as the medicinal part of P. vulgaris, as described in the Chinese Pharmacopoeia(2020 edition).
Antioxidants/chemistry* ; Tandem Mass Spectrometry/methods* ; Prunella/chemistry* ; Chromatography, High Pressure Liquid/methods* ; Caffeic Acids ; Flavonoids/analysis* ; Triterpenes/analysis* ; Saponins ; Sugars

Alkaloids are important active ingredients occurring in many traditional Chinese medicines, and alkaloid glycosides are one of their existence forms. The introduction of saccharide units improves the water solubility of alkaloid glycosides thus presenting better biological activity.Because of the low content in plants, alkaloid glycosides have been not comprehensively studied. In this study, ultrahigh performance liquid chromatography-quadrupole time of flight-tandem mass spectrometry(UPLC-QTOF-MS/MS) was employed to identify and analyze the alkaloid glycosides in Coptis chinensis, Phellodendron chinense, Menispermum dauricum, Sinomenium acutum, Tinospora sagittata and Stephania tetrandra. The results showed that except Tinospora sagittata, the other five herbal medicines contained alkaloid glycosides. Furthermore, the alkaloid glycosides in each herbal medicine were identified based on UV absorption spectra, quasimolecular ion peaks in MS, fragment ions information in the MS/MS, and previous literature reports. A total of 42 alkaloid glycosides were identified. More alkaloid glycosides were identified in C. chinensis and Menispermum dauricum, and eleven in C. chinensis were potential new compounds. Furthermore, the alkaloid glycosides in the water extract of C. chinensis were coarsely se-parated by macroporous adsorption resin, purified by column chromatography with D151 cation exchange resin, ODS and MCI, combined with semi-preparative high performance liquid chromatography. Two new alkaloid glycosides were obtained, and their structures were identified by mass spectrometry and NMR data as(S)-7-hydroxy-1-(p-hydroxybenzyl)-2,2-N,N-dimethyl-1,2,3,4-tetrahydroisoquinoline-6-O-β-D-glucopyranoside and(S)-N-methyltetrahydropalmatubine-9-O-β-D-glucopyranoside, respectively. This study is of great significance for enriching the information about the chemical composition and the in-depth development of C. chinensis. Meanwhile, it can provide a reference for rapid identification and isolation of alkaloid glycosides from other Chinese herbal medicines.
Glycosides/chemistry* ; Medicine, Chinese Traditional ; Tandem Mass Spectrometry/methods* ; Coptis chinensis ; Drugs, Chinese Herbal/chemistry* ; Alkaloids/analysis* ; Plant Extracts/chemistry* ; Antineoplastic Agents ; Plants, Medicinal/chemistry* ; Water ; Chromatography, High Pressure Liquid/methods* ; Coptis/chemistry*

A method based on ultra-high performance liquid chromatography coupled with triple quadrupole linear ion trap-tandem mass spectrometry(UHPLC-QTRAP-MS/MS) was developed for the simultaneous determination of 41 bioactive constituents of flavonoids, organic acids, nucleosides, and amino acids in Lysimachiae Herba. The content of multiple bioactive constituents was compared among the samples from different habitats. The chromatographic separation was performed in a Waters XBridge®C_(18) column(4.6 mm×100 mm, 3.5 μm) at 30 ℃. The gradient elution was performed with 0.4% methanol(A)-formic acid water(B) as the mobile phase at a flow rate of 0.8 mL·min~(-1), and the multiple-reaction monitoring(MRM) mode was adopted. According to the content of 41 constituents, hierarchical cluster analysis(HCA), orthogonal partial least squares discriminant analysis(OPLS-DA), and gray relational analysis(GRA) were perfomed to comprehensively evaluate the samples from different habitats. The results showed that the 41 constituents exhibited good linear relationship within the tested concentration ranges, with the correlation coefficients(r) greater than 0.999 4. The method featured good precision, repeatability, and stability with the relative standard deviations(RSDs) less than 5.0%. The average recoveries of the 41 constituents ranged from 98.06% to 101.9%, with the RSDs of 0.62%-4.6%. HCA and OPLS-DA separated 48 batches of Lysimachiae Herba samples from different habitats into three categories: the producing areas in Sichuan and Chongqing, the producing areas in Jiangsu, Zhejiang, and Jiangxi, and the producing areas in Guizhou. The content of 41 constituents varied among the Lysimachiae Herba samples from different habitats. The GRA results revealed that the Lysimachiae Herba sample from Nanchong City, Sichuan Province had the best comprehensive quality. The method developed in this study was accurate and reliable and thus can be used for comprehensive evaluation of Lysimachiae Herba quality and provide basic information for the selection of habitats.
Tandem Mass Spectrometry/methods* ; Multivariate Analysis ; Chromatography, High Pressure Liquid/methods* ; Drugs, Chinese Herbal/chemistry* ; Amino Acids/analysis*

The Compound Cheqian Tablets are derived from Cheqian Power in Comprehensive Recording of Divine Assistance, and they are made by modern technology with the combination of Plantago asiatica and Coptis chinensis. To investigate the material basis of Compound Cheqian Tablets in the treatment of diabetic nephropathy, in this study, the chemical components of Compound Cheqian Tablets were characterized and analyzed by UPLC-Q-TOF-MS/MS, and a total of 48 chemical components were identified. The identified chemical compounds were analyzed by network pharmacology. By validating with previous literature, six bioactive compounds including acteoside, isoacteoside, coptisine, magnoflorine, palmatine, and berberine were confirmed as the index components for qua-lity evaluation. Furthermore, the content of the six components in the Compound Cheqian Tablets was determined by the "double external standards" quantitative analysis of multi-components by single marker(QAMS), and the relative correction factor of isoacteoside was calculated as 1.118 by using acteoside as the control; the relative correction factors of magnoflorine, palmatine, and berberine were calculated as 0.729, 1.065, and 1.126, respectively, by using coptisine as the control, indicating that the established method had excellent stability under different conditions. The results obtained by the "double external standards" QAMS approximated those obtained by the external standard method. This study qualitatively characterized the chemical components in the Compound Cheqian Tablets by applying UPLC-Q-TOF-MS/MS and screened the pharmacodynamic substance basis for the treatment of diabetic nephropathy via network pharmacology, and primary pharmacodynamic substance groups were quantitatively analyzed by the "double external stan-dards" QAMS method, which provided a scientific basis for clarifying the pharmacodynamic substance basis and quality control of Compound Cheqian Tablets.
Humans ; Tandem Mass Spectrometry ; Berberine/pharmacology* ; Chromatography, High Pressure Liquid/methods* ; Network Pharmacology ; Diabetic Nephropathies ; Drugs, Chinese Herbal/chemistry* ; Quality Control ; Tablets

This study developed an optimal pre-processing technique for the reference substance of the classic formula Gualou Xiebai Banxia Decoction(GXBD) and established a comprehensive quality control method for GXBD reference substance to provide a reference for its overall quality evaluation. The authors prepared 15 batches of GXBD samples and innovatively used the extracted ion chromatogram under the base peak chromatogram mode to establish a liquid chromatography-mass spectrometry(LC-MS) fingerprint, identify characteristic peaks, and perform quantitative analysis of indicator components. The yield of the 15 batches of GXBD samples ranged from 50.28% to 76.20%. In the positive ion mode, 12 common characteristic peaks were detected in the LC-MS fingerprint, and the structures of five common peaks were identified by comparison with reference standards. The similarity between the fingerprint profiles of different batches of samples and the reference fingerprint profile ranged from 0.920 to 0.984. Finally, liquid chromatography-triple quadrupole mass spectrometry(LC-QQQ/MS) in multiple reaction monitoring(MRM) mode was used to determine the content of eight indicator components in GXBD, including loliolide, chrysoeriol, rutin, cucurbitacin D, macrostemonoside Ⅰ, 25S-timosaponin B Ⅱ, 25R-timosaponin B Ⅱ, and peptide proline-tryptophan-valine-proline-glycine(PWVPG). The method established in this study can reduce matrix interference in the compound, and it has good accuracy, stability, and practical value. It effectively reflects the quality attributes of GXBD samples and can be used for the comprehensive quality control of GXBD.
Chromatography, Liquid ; Tandem Mass Spectrometry/methods* ; Drugs, Chinese Herbal/chemistry* ; Proline ; Chromatography, High Pressure Liquid/methods*