OBJECTIVES: To identify 1-(4-fluorophenyl)-2-(1-pyrrolidinyl) pentan-1-one (4-F-α-PVP) analog 1-(4-fluoro-3-methyl phenyl)-2-(1-pyrrolidinyl) pentan-1-one (4-F-3-Methyl-α-PVP) hydrochloride without reference substance. METHODS: The direct-injection electron ionization-mass spectrometry (EI-MS), GC-MS, electrospray ionization-high resolution mass spectrometry (ESI-HRMS), ultra-high performance liquid chromatography-high resolution tandem mass spectrometry (UPLC-HRMS/MS), nuclear magnetic resonance (NMR), ion chromatography and Fourier transform infrared spectroscopy (FTIR) were integrated utilized to achieve the structural analysis and characterization of the unknown compound in the sample, and the cleavage mechanism of the fragment ions was deduced by EI-MS and UPLC-HRMS/MS. RESULTS: By analyzing the direct-injection EI-MS, GC-MS, ESI-HRMS and UPLC-HRMS/MS of the compound in the samples, it was concluded that the unknown compound was a structural analog of 4-F-α-PVP, possibly with one more methyl group in the benzene ring. According to the analysis results of ¹H-NMR and ¹³C-NMR, it was further proved that the methyl group is located at the 3-position of the benzene ring. Since the actual number of hydrogen in ¹H-NMR analysis was one more than 4-F-3-Methyl-α-PVP neutral molecule, it was inferred that the compound existed in the form of salt. Ion chromatography analysis results showed that the compound contained chlorine anion (content 11.14%-11.16%), with the structural analysis of main functional group information by FTIR, the unknown compound was finally determined to be 4-F-3-Methyl-α-PVP hydrochloride. CONCLUSIONS A comprehensive method using EI-MS, GC-MS, ESI-HRMS, UPLC-HRMS/MS, NMR, ion chromatography and FTIR to identify 4-F-3-Methyl-α-PVP hydrochloride in samples is established, which will be helpful for the forensic science laboratory to identify this compound or other analog compounds.
Benzene ; Gas Chromatography-Mass Spectrometry/methods* ; Spectrometry, Mass, Electrospray Ionization ; Chromatography, High Pressure Liquid/methods*

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*

The quality of Paeoniae Radix Alba and Paeoniae Radix Rubra is evaluated by root thickness, and paeoniflorin serves as a common quality indicator of them. However, the correlation between the content of bioactive compounds and the root size is still unclear. Therefore, this study characterized the distribution patterns and content of seven bioactive compounds including paeoniflorin in different tissues of Paeonia lactiflora roots, analyzed the correlation between the root size and the content of bioactive compounds based on the xylem-to-bark ratio, and further determined the index components for quality assessment. Nine samples of fresh P. lactiflora roots were collected from the genuine cultivation area. The distribution of bioactive compounds in different tissues on the cross-section of the root was firstly analyzed by desorption electrospray ionization-mass spectrometry imaging(DESI-MSI). Subsequently, the content of bioactive compounds was determined in the xylems and barks of the roots by UPLC. The compounds with the largest difference between the xylem and the bark were selected by orthogonal partial least squares discriminant analysis(OPLS-DA). The results indicated that paeoniflorin, benzoylpaeoniflorin, oxypaeoniflorin, gallic acid, and 1,2,3,4,6-pentagalloylglucose were significantly accumulated in the xylems, while albiflorin and catechin were mainly distributed in the barks. Paeoniflorin and albiflorin, with the largest differences in the xylem and the bark, had the highest content in the two tissues. The root diameter was positively correlated with paeoniflorin content and negatively correlated with albiflorin content. As isomers with different efficacies, paeoniflorin or albiflorin can be chosen as the quality marker corresponding to specific clinical application to launch quality classification evaluation of multi-functional Chinese medicines.
Bridged-Ring Compounds ; Catechin/analysis* ; Chromatography, High Pressure Liquid/methods* ; Gallic Acid/analysis* ; Monoterpenes/analysis* ; Paeonia/chemistry* ; Plant Roots/chemistry* ; Spectrometry, Mass, Electrospray Ionization

Achyranthes bidentata Blume is widely used as a traditional Chinese medicine with the effects of nourishing the liver and kidneys and strengthening muscles and bones. In this work, a rapid and simple strategy was developed for characterizing phytoecdysteroids by ultra-high-performance liquid chromatography coupled with liner ion trap-Orbitrap mass spectrometry using electrospray ionization in the negative mode. As a result, 47 phytoecdysteroids were unambiguously or tentatively characterized. Among them, seven known compounds were identified according to the reference standards along with molecular formula, retention time and fragmentation patterns, while others were mostly potential new compounds. Through targeted isolation, the structures of three new compounds were determined by NMR spectra, which were consistent with LC-MS characterization. The present study provides an efficient method to deeply characterize phytoecdysteroids.
Achyranthes/chemistry* ; Chromatography, High Pressure Liquid/methods* ; Gas Chromatography-Mass Spectrometry ; Mass Spectrometry ; Medicine, Chinese Traditional ; Spectrometry, Mass, Electrospray Ionization/methods*

Odontogenic tumors are rare lesions with unknown etiopathogenesis. Most of them are benign, but local aggressiveness, infiltrative potential, and high recurrence rate characterize some entities. The MAP-kinase pathway activation can represent a primary critical event in odontogenic tumorigenesis. Especially, the BRAF V600E mutation has been involved in 80-90% of ameloblastic lesions, offering a biological rationale for developing new targeted therapies. The study aims to evaluate the BRAF V600E mutation in odontogenic lesions, comparing three different detection methods and focusing on the Sequenom MassARRAY System. 81 surgical samples of odontogenic lesions were subjected to immunohistochemical analysis, Sanger Sequencing, and Matrix-Assisted Laser Desorption/Ionization-Time of Flight mass spectrometry (Sequenom). The BRAF V600E mutation was revealed only in ameloblastoma samples. Moreover, the presence of BRAF V600E was significantly associated with the mandibular site (ρ = 0.627; P value <0.001) and the unicystic histotype (ρ = 0.299, P value <0.001). However, any significant difference of 10-years disease-free survival time was not revealed. Finally, Sequenom showed to be a 100% sensitive and 98.1% specific, suggesting its high-performance diagnostic accuracy. These results suggest the MAP-kinase pathway could contribute to ameloblastic tumorigenesis. Moreover, they could indicate the anatomical specificity of the driving mutations of mandibular ameloblastomas, providing a biological rational for developing new targeted therapies. Finally, the high diagnostic accuracy of Sequenom was confirmed.
Ameloblastoma/pathology* ; Carcinogenesis ; Humans ; Mitogen-Activated Protein Kinases/genetics* ; Mutation ; Odontogenic Tumors/pathology* ; Proto-Oncogene Proteins B-raf/metabolism* ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

The ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS~E) technology was employed to compare the chemical components between the aerial and underground parts of Coptis chinensis samples from different batches. According to the retention time, molecular ion peak, and LC-MS~E fragment information of the reference substances and available literature, we identified a total of 40 components. Thirty-three and 31 compounds were respectively identified in the underground part(taproots) and the aerial part(stems and leaves) of C. chinensis. Among them, 24 compounds, including alkaloids(e.g., berberine and jatrorrhizine) and phenolic acids(e.g., chlorogenic acid, quinic acid, and tanshinol), were common in the two parts. In addition, differential components were also identified, such as magnoline glucoside in the underground part and(±) lariciresionol-4-β-D-glucopyranoside in the aerial part. The analysis of fragmentation pathways based on spectra of reference substances indicated the differences among samples of different batches. Furthermore, we performed the principal component analysis(PCA) for the peak areas of C. chinensis in different batches. The results showed that the underground part and the aerial part were clearly clustered into two groups, indicating that the chemical components contained in the two parts were different. Furthermore, the results of partial least squares discriminant analysis(PLS-DA) identified 31 differential compounds(VIP value>1) between the underground part and the aerial part, mainly including alkaloids, phenolic acids, lignans, and flavonoids. This study proves that C. chinensis possesses great development potential with multiple available compounds in stems and leaves. Moreover, it sheds light on for the development and utilization of non-medicinal organs of C. chinensis and other Chinese medicinal herbs.
Chromatography, High Pressure Liquid/methods* ; Coptis chinensis ; Spectrometry, Mass, Electrospray Ionization/methods* ; Tandem Mass Spectrometry/methods* ; Technology

In this study, a method was established for in-situ visualization of metabolite distribution in the rhizome of Paris polyphylla var. yunnanensis. To be specific, through matrix-assisted laser desorption/ionization-mass spectrometry imaging(MALDI-MSI), the spatial locations of steroidal saponins, amino acids, organic acids, phytosterols, phytoecdysones, nucleosides, and esters in rhizome of the medicinal plant were directly analyzed, and six unknown compounds with differential distribution in rhizome tissues were identified. The specific procedure is as follows: preparation of rhizome tissue section, matrix screening and optimization, and MALDI-MSI analysis. The results showed that the steroidal saponins were mainly distributed in the central, amino acids in epidermis and cortex, low-molecular-weight organic acids in central epidermis, phytosterols in the epidermis and lateral cortex, the phytoecdysones in epidermis and cortex, nucleosides(uneven distribution) in epidermis and cortex, growth hormones around the epidermis and cortex, particularly outside the cortex, and esters in cortex with unobvious difference among different tissues. In this study, the spatial distribution of meta-bolites in the rhizome of P. polyphylla var. yunnanensis was characterized for the first time. The result can serve as a reference for identifying and extracting endogenous metabolites of P. polyphylla var. yunnanensis, exploring the synthesis and metabolism mechanisms of the metabolites, and evaluating the quality of medicinal materials.
Liliaceae/chemistry* ; Melanthiaceae ; Rhizome/chemistry* ; Saponins/analysis* ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

Zhachong Shisanwei Pills, composed of 13 Chinese medicinal materials, are used for treating the diseases such as hemiplegia, pain of muscles and bones, rheumatism, and joint pain. The chemical composition and pharmacodynamics of Zhachong Shisanwei Pills have not been reported. Ultra-performance liquid chromatography/quadrupole-time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS/MS) was employed to quickly identify the chemical components of Zhachong Shisanwei Pills, which was performed with Shim-pack GIST C_(18) column(4.6 mm×150 mm, 5 μm). The gradient elution was conducted with methanol-0.05% acetic acid as the mobile phase. Electrospray ionization mass spectrometry(ESI-MS) was carried out in both positive and negative ion modes. The compounds were identidied based on accurate relative molecular weight, fragment ion species, and the MS data of reference substances and in literature. In conclusion, a total of 98 compounds were identified, including 19 organic acids, 36 flavonoids, 13 volatile oils, 8 tannins, 5 2-(2-phenylethyl)chromones, 5 amino acids, 3 sesquiterpenoids, 3 alkaloids, and 2 other compounds. This study characte-rized the chemical components of Zhachong Shisanwei Pills rapidly for the first time, laying a foundation for further research on the pharmacodynamic material basis and quality evaluation.
Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Drugs, Chinese Herbal/chemistry* ; Spectrometry, Mass, Electrospray Ionization ; Tandem Mass Spectrometry

Aims: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is increasingly used to identify Candida spp. in diagnostic laboratories due to its strength in providing accurate information results, speed and cost-effectiveness. However, its accuracy varies on instrument platform, reference database, sample preparation techniques and interlaboratory comparisons. Therefore, the use of MALDI-TOF MS for species identification was evaluated against traditional biochemical identification, namely BrillianceTM Candida and Remel RapIDTM Yeast Plus System. Methodology and results: To evaluate and compare identification efficiency, turnaround time and consumable cost, 194 clinical isolates of Candida were collected. The results showed overall 85.6% concordant identification between two methods with 94.9-99.5% and 100% accuracy in traditional and MALDI-TOF MS, respectively, in the identification of four common Candida species; C. albicans, C. tropicalis, C. parapsilosis sensu stricto and C. glabrata sensu stricto. Other Candida species were also identified with 85.6% and 97.5% accuracy rates by traditional and MALDI-TOF MS, respectively. Additionally, identification using MALDI-TOF MS reduced overall turnaround time and cost by approximately 99.8% and 86.5%, respectively. Conclusion, significance and impact of study This study highlights the performance of MALDI-TOF MS, which is more accurate in identifying Candida spp. with a less hands-on approach, cheaper cost and shorter turnaround time.
Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Candida ; Tertiary Care Centers

OBJECTIVES: To analyze the chemical structure of the interfering substance that affects the result of methamphetamine analysis in wastewater. METHODS: A combination of GC-MS and liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) was used to analyze the mass spectrum characteristics of the interfering substance that affects the result of methamphetamine analysis and to infer its possible structure. Liquid chromatography-triple quadrupole-mass spectrometry (LC-TQ-MS) was used to confirm the control material. RESULTS: Using LC-QTOF-MS in positive electrospray ionization (ESI⁺) mode, the mass-to-charge ratio (m/z) of quasi-molecular ion in the MS¹ mass spectrometry of interfering substance was identical to that of methamphetamine, indicating that the interfering substance was probably an isomer of methamphetamine. The MS² mass spectra obtained at three collision energies of 15 V, 30 V and 45 V were highly similar to methamphetamine, suggesting that the interfering substance contained methylamino and benzyl groups. Further analysis using GC-MS in electron impact (EI) ionization mode showed that the base peak in the mass spectrum of the interfering substance was at m/z 44. The interfering substance was confirmed to be N-methyl-2-phenylpropan-1-amine by compared with the standard reference. CONCLUSIONS The chemical structure of N-methyl-2-phenylpropan-1-amine is highly similar to methamphetamine, which is easy to cause interference for the detection of trace amounts of methamphetamine in wastewater using LC-TQ-MS. Therefore, in the actual analysis, the chromatographic retention time can be used to distinguish between N-methyl-2-phenylpropan-1-amine and methamphetamine.
Methamphetamine ; Wastewater ; Amines ; Gas Chromatography-Mass Spectrometry/methods* ; Mass Spectrometry/methods* ; Spectrometry, Mass, Electrospray Ionization/methods*