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*

The chemical constituents of Chuanzhi Tongluo Capsules were analyzed and identified using ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap high-resolution mass spectrometry(UPLC-Q-Exactive Orbitrap-MS) to clarify the pharmacological substance basis. In addition, network pharmacology was employed to explore the mechanism of Chuanzhi Tongluo Capsules in the treatment of cerebral infarction. Gradient elution was performed using acetonitrile and 1% acetic acid in water as the mobile phase. Mass spectrometry was performed in positive and negative ion modes. Xcalibur 4.2 software was used for compound analysis, including accurate mass-to-charge ratio and MS/MS fragment information, combined with the comparison of reference standards and literature data. A total of 152 compounds were identified, including 32 organic acids, 35 flavonoids and their glycosides, 33 diterpenes, 13 phthalides, 12 triterpenes and triterpene saponins, 23 nitrogen-containing compounds, and 4 other compounds, and their fragmentation patterns were analyzed. SwissTargetPrediction, GeneCards, DAVID, and other databases were used to predict and analyze the core targets and mechanism of Chuanzhi Tongluo Capsules. Protein-protein interaction(PPI) network topology analysis identified 10 core targets, including TNF, VEGFA, EGFR, IL1B, and CTNNB1. KEGG enrichment analysis showed that Chuanzhi Tongluo Capsules mainly exerted their effects through the regulation of lipid and atherosclerosis, glycoproteins in cancer, MicroRNAs in cancer, fluid shear stress, and atherosclerosis-related pathways. Molecular docking was performed between the key constituents and core targets, and the results demonstrated a strong binding affinity between the key constituents of Chuanzhi Tongluo Capsules and the core targets. This study comprehensively elucidated the chemical constituents of Chuanzhi Tongluo Capsules and explored the core targets and mechanism in the treatment of cerebral infarction based on network pharmacology, providing a scientific reference for the study of the pharmacological substance basis and formulation quality standards of Chuanzhi Tongluo Capsules.
Humans ; Tandem Mass Spectrometry/methods* ; Chromatography, High Pressure Liquid/methods* ; Molecular Docking Simulation ; Network Pharmacology ; Drugs, Chinese Herbal/pharmacology* ; Capsules ; Atherosclerosis ; Cerebral Infarction ; Neoplasms

Traditional Chinese medicine(TCM) compound preparations have complex compositions. As a widely used TCM injection, Shuganning Injection, its in vivo processes are not yet fully understood. Determining the plasma protein binding rate is of great significance for pharmacokinetic and pharmacodynamic studies. In this experiment, the equilibrium dialysis method combined with UPLC-MS/MS technology was used to determine the plasma protein binding rates of 10 components, including p-hydroxyacetophenone, caffeic acid, baicalein, oroxylin A, geniposide, baicalin, cynaroside, oroxylin A-7-O-β-D-glucuronide, scutellarin, and hyperoside, in Shuganning Injection in rat and human plasma to provide a theoretical basis for further elucidating the in vivo processes of Shuganning Injection and guiding clinical medication. The results showed that, except for baicalein and geniposide, the plasma protein binding rates of the other eight components were higher in human plasma than in rat plasma, and there were interspecies differences. In human plasma, except for geniposide, caffeic acid, and baicalin, the plasma protein binding rates of the remaining seven components were above 80%, with baicalein and oroxylin A exceeding 90%. All components exhibit a high level of binding to plasma proteins, with the exception of geniposide.
Rats ; Humans ; Animals ; Tandem Mass Spectrometry/methods* ; Chromatography, Liquid/methods* ; Rats, Sprague-Dawley ; Liquid Chromatography-Mass Spectrometry ; Protein Binding ; Renal Dialysis ; Drugs, Chinese Herbal ; Blood Proteins ; Chromatography, High Pressure Liquid/methods*

Simiao Yong'an Decoction is a classic prescription for treating gangrene. Modern medical evidence has proven that Si-miao Yong'an Decoction has therapeutic effects on atherosclerosis(AS), vascular occlusion angeitides, and hypertension, while its pharmacodynamic mechanism remains unclear. The evidence of network pharmacology, molecular docking, literature review, and our previous study suggests that luteolin and kaempferol are two major flavonoids in Simiao Yong'an Decoction and can inhibit macrophage inflammation and exert anti-AS effects. However, due to lack of the metabolism studies in vivo, little is known about the metabolic characteristics of luteolin and kaempferol. This study employed ultra-performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS/MS) and relevant software to identify the metabolites and metabolic pathways of luteolin and kaempferol in rat plasma, urine, and feces, after oral administration of luteolin and kaempferol, respectively. After the administration of luteolin, 10, 11, and 3 metabolites of luteolin were detected in the plasma, urine, and feces, respectively. After the administration of kaempferol, 9, 3, and 1 metabolites of kaempferol were detected in the plasma, urine, and feces, respectively. The metabolic pathways mainly involved methylation, glucuronidation, and sulfation. This study enriches the knowledge about the pharmacological mechanism of luteolin and kaempferol and supplies a reference for revealing the metabolic process of other flavonoids in Simiao Yong'an Decoction, which is of great significance for elucidating the pharmacological effects and effective substances of this decoction in vivo.
Rats ; Animals ; Tandem Mass Spectrometry/methods* ; Luteolin/analysis* ; Drugs, Chinese Herbal/chemistry* ; Kaempferols/analysis* ; Chromatography, High Pressure Liquid/methods* ; Molecular Docking Simulation