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1.
J Agric Food Chem ; 69(16): 4849-4857, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33849274

RESUMO

Due to the high price and limited supply of Panax notoginseng, a large number of samples adulterated with the leaves appear in the market. A group of new malonyl ginsenosides were exclusively detected in the P. notoginseng leaves (PNL). Targeted isolation of the malonyl ginsenosides was guided by UPLC-QDa MS. HRMS, 1D/2D NMR, and chemical methods were used for structural identification. A selected ion monitoring method was developed based on UPLC-QDa MS to detect the adulterations. In addition, the anti-inflammatory activities and the collision-induced dissociation features of the isolated saponins were studied. As a result, eight new 3-OH malonylated dammarane-type triterpene oligoglycosides (notoginsenosides L3-L10) were obtained from PNL. Adulteration with PNL can be easily detected with limit of detection as low as 0.06%. To sum up, the isolated ginsenosides can be used as quality markers for fraud detection, which will promote the quality control of the notoginseng products.


Assuntos
Ginsenosídeos , Panax notoginseng , Panax , Saponinas , Espectroscopia de Ressonância Magnética , Folhas de Planta
2.
Chin J Nat Med ; 19(1): 70-80, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33516454

RESUMO

Pesticides' overuse and misuse have been reported to induce ingredient variations in herbal medicine, which is now gaining attention in the medicinal field as a form of alternative medicine. To date, available studies on pesticide-induced ingredient variations of herbal medicine are limited only on a few compounds and remain most others unexamined. In this study, a plant metabolomics-based strategy was performed to systematically explore the effects of two frequently used insecticides on the comprehensive constituents of Lonicerae Japonicae Flos (LJF), the flower buds of Lonicera japonica Thunb. Field trials were designed on a cultivating plot of L. japonica with controls and treatments of imidacloprid (IMI) and compound flonicamid and acetamiprid (CFA). Unbiased metabolite profiling was conducted by ultra-high performance liquid chromatography/quadrupole-Orbitrap mass spectrometer. After data pretreatment by automatic extraction and screening, a data matrix of metabolite features was submitted for statistical analyses. Consequently, 29 metabolic markers, including chlorogenic acids, iridoids and organic acid-glucosides were obtained and characterized. The relative quantitative assay was subsequently performed to monitor their variations across flowering developments. This is the first study that systematically explored the insecticide-induced metabolite variations of LJF while taking into account the inherent variability of flowering development. The results were beneficial for holistic quality assessment of LJF and significant for guiding scientific use of pesticides in the large-scale cultivation.


Assuntos
Medicamentos de Ervas Chinesas , Inseticidas , Lonicera , Metabolômica , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Flores/metabolismo , Inseticidas/farmacologia , Lonicera/efeitos dos fármacos , Lonicera/metabolismo , Plantas Medicinais/efeitos dos fármacos , Plantas Medicinais/metabolismo
3.
J Chromatogr A ; 1538: 34-44, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29395157

RESUMO

Liquid chromatography-mass spectrometry (LC-MS) guided isolation is a favored strategy to quickly and efficiently explore the chemical diversity of herbal medicines. In this study, two methods were adopted to improve the performance of the strategy, including offline two-dimensional (2D) LC to extend the peak capacities and predicted metabolites screening (PMS) to automatically screen the targets with expanded databases. Ginsenosides in the leaves of Panax notoginseng (PNL) were taken as a case. An offline 2D LC system was constructed with an orthogonality of 0.69 and peak capacity of 8925. Quadrupole time-of-flight mass spectrometry-fast data directed analysis (QTOF-Fast DDA) was employed for detection of the ginsenosides in the fractioned samples. Four modified groups, including glucose, xylose, rhamnose and malonyl, were adopted and markedly extended the screening coverage. The combined strategy showed about 7.5 times improvement in the screening capability. PMS is conveniently and automatically implemented in UNIFI. Using this strategy, 945 ginsenosides were discovered from PNL, including 662 potentially novel ginsenosides. Furthermore, two new ginsenosides were purified, and unambiguously identified by NMR analysis, partially demonstrating the LC-MS guided isolation. The combined strategy can also be applied in characterizing and discovering new bioactive constituents from other herbal medicines.


Assuntos
Ginsenosídeos/química , Medicina Herbária/métodos , Panax notoginseng/química , Folhas de Planta/química , Cromatografia Líquida , Ginsenosídeos/análise , Espectroscopia de Ressonância Magnética , Plantas Medicinais/química , Espectrometria de Massas em Tandem
4.
J Chromatogr A ; 1491: 87-97, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28256254

RESUMO

Targeted identification of potentially bioactive molecules from herbal medicines is often stymied by the insufficient chromatographic separation, ubiquitous matrix interference, and pervasive isomerism. An enhanced targeted identification strategy is presented and validated by the selective identification of flavonoid O-glycosides (FOGs) from Carthamus tinctorius. It consists of four steps: (i) enhanced separation and detection by offline two-dimensional liquid chromatography/LTQ-Orbitrap MS (offline 2D-LC/LTQ-Orbitrap MS) using collision-induced dissociation (CID) and high-energy C-trap dissociation (HCD); (ii) improved identification of the major aglycones by acid hydrolysis and LC-SPE-NMR; (iii) simplified spectral elucidation by high-resolution diagnostic product ions/neutral loss filtering; and (iv) more convincing structural identification by matching an in-house library. An offline 2D-LC system configuring an Acchrom XAmide column and a BEH Shield RP-18 UPLC® column enabled much better separation of the easily co-eluting components. Combined use of CID and HCD could produce complementary fragmentation information. The intensity ratios of the aglycone ion species ([Y0-H]-/Y0- and [Y0-2H]-/Y0-) in the HCD-MS2 spectra were found diagnostic for discriminating the aglycone subtypes and characterizing the glycosylation patterns. Five aglycone structures (kaempferol, 6-hydroxykaempferol, 6-methoxykaempferol, carthamidin, and isocarthamidin) were identified based on the 1H-NMR data recorded by LC-SPE-NMR. Of the 107 characterized flavonoids, 80 FOGs were first reported from C. tinctorius. Unknown aglycones, pentose, and novel acyl substituents were discovered. A new compound thereof was isolated and fully identified, which could partially validate the MS-oriented identification. This integral strategy can improve the potency, efficiency, and accuracy in the detection of new compounds from medicinal herbs and other natural sources.


Assuntos
Carthamus tinctorius/química , Cromatografia Líquida/métodos , Flavonoides , Glicosídeos , Espectrometria de Massas/métodos , Flavonoides/análise , Flavonoides/química , Flavonoides/isolamento & purificação , Glicosídeos/análise , Glicosídeos/química , Glicosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Extração em Fase Sólida
5.
Anal Chim Acta ; 952: 59-70, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28010843

RESUMO

The simultaneous identification and quantification of target metabolites from herbal medicines are difficult to implement by the full-scan MS based nontargeted metabolomics approaches. Here an in-source multiple collision-neutral loss filtering (IMC-NLF) based nontargeted metabolomics approach is developed and applied to identify and quantify the variations of malonyl-ginsenosides, a common group of acyl saponins with potential anti-diabetic activity, among Panax ginseng, P. quinquefolius, and P. notoginseng. The key steps of the IMC-NLF strategy are the acquisition of specific high-resolution neutral loss data and the efficient filtering of target precursor ions from the full-scan spectra. Using a hybrid LTQ-Orbitrap mass spectrometer after UHPLC separation, abundant in-source product ions, [M-H-CO2]- (due to the vulnerability of the carboxyl group) and [M-H-Mal.]-, were generated at the energies of 70 V and 90 V, respectively. After spectral deconvolution, the generated peak list was screened by dual NLF using a Neutral Loss MS Finder software (NL of 43.9898 Da for CO2 and 86.0004 Da for the malonyl substituent). By combining the precursor ions list-triggered HCD-MS/MS and basic hydrolysis, a total of 101 malonyl-ginsenosides (including 69 from P. ginseng, 52 from P. quinquefolius, and 44 from P. notoginseng) were identified or tentatively characterized. The variations of 81 characterized malonyl-ginsenosides among 45 batches of Ginseng samples were statistically analyzed disclosing ten potential markers. It is the first systematic analysis of malonyl-ginsenosides. The IMC-NLF approach by a single analytical platform is promising in targeted analyses of modification-specific metabolites in metabolomics and drug metabolism.


Assuntos
Ginsenosídeos/análise , Metabolômica , Panax/química , Cromatografia Líquida de Alta Pressão , Panax/classificação , Espectrometria de Massas em Tandem
6.
Fitoterapia ; 116: 85-92, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27889541

RESUMO

Four new alkaloids, comprising three 3-oxo-3,7-seco-oxindole alkaloids (hirsutanine D-F, 1-3) and one oxindole alkaloid N-oxide (uncarine B N-oxide, 4), together with four known heteroyohimbine-type oxindole alkaloids, were isolated from the stems of Uncaria hirsuta Havil. Structures of 1-4 were elucidated by extensive NMR and HR-ESIMS data analyses. Compound 3 is the first 3-oxo-3,7-seco-oxindole alkaloid with ring B opened and degraded isolated from the Uncaria genus. Compounds 1-3 exhibited slight inhibition effect on the proliferation of the breast cancer cell MDA-MB-231. The positive mode collision-induced dissociation of the 3-oxo-3,7-seco-oxindole alkaloids (1-3) was featured by the ß-cleavage and α-cleavage of the amido bond, while the N-oxide (4) showed characteristic neutral eliminations of ·OH and H2O.


Assuntos
Alcaloides/química , Indóis/química , Monoterpenos/química , Alcaloides/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Indóis/isolamento & purificação , Estrutura Molecular , Monoterpenos/isolamento & purificação , Oxindóis , Caules de Planta/química , Uncaria/química
7.
J Chromatogr A ; 1409: 159-65, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26209189

RESUMO

An efficient and target-oriented sample enrichment method was established to increase the content of the minor alkaloids in crude extract by using the corresponding two-phase solvent system applied in pH-zone-refining counter-current chromatography. The enrichment and separation of seven minor indole alkaloids from Uncaria rhynchophylla (Miq.) Miq. ex Havil(UR) were selected as an example to show the advantage of this method. An optimized two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (3:7:1:9, v/v) was used in this study, where triethylamine (TEA) as the retainer and hydrochloric acid (HCl) as the eluter were added at the equimolar of 10mM. Crude alkaloids of UR dissolved in the corresponding upper phase (containing 10mM TEA) were extracted twice with lower phase (containing 10mM TEA) and lower phase (containing 10mM HCl), respectively, the second lower phase extract was subjected to pH-zone-refining CCC separation after alkalization and desalination. Finally, from 10g of crude alkaloids, 4g of refined alkaloids was obtained and the total content of seven target indole alkaloids was increased from 4.64% to 15.78%. Seven indole alkaloids, including 54mg isocorynoxeine, 21mg corynoxeine, 46mg isorhynchophylline, 35mg rhynchophylline, 65mg hirsutine, 51mg hirsuteine and 27mg geissoschizine methylether were all simultaneously separated from 2.5g of refined alkaloids, with the purity of 86.4%, 97.5%, 90.3%, 92.1%, 98.5%, 92.3%, and 92.8%, respectively. The total content and purities of the seven minor indole alkaloids were tested by HPLC and their chemical structures were elucidated by ESI-HRMS and (1)H NMR.


Assuntos
Alcaloides Indólicos/isolamento & purificação , Acetatos , Cromatografia Líquida de Alta Pressão/métodos , Distribuição Contracorrente/métodos , Hexanos , Concentração de Íons de Hidrogênio , Metanol , Extratos Vegetais/química , Solventes , Uncaria/química
8.
Zhongguo Gu Shang ; 23(8): 624-5, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20860144

RESUMO

OBJECTIVE: To explore the advantages of conservative treatment for trauma of children,and evaluate effect of external fixation for the treatment of double fractures of forearm. METHODS: From June 2007 to June 2008, 52 patients with double fractures of forearm were treated with manipulative reduction and modified external fixation by splints. Among them, 33 males and 19 females,the age was from 4 to 15 years with an average of 8.6 years. The course of disease was from 1 hour to 7 days. All patients had a definite history of trauma, and pre-treatment X-ray film showed double fracture of ulna and radius. RESULTS: All patients were followed up from 6 to 14 months with an average of 9.4 months. All fractures healed and the healing time was from 4 to 8 weeks with an average of 6 weeks. The clinical effect was evaluated according to Berton criteria, 37 cases obtained excellent result, 15 good. CONCLUSION: Strict choose indication of conservative treatment can obtain satisfied effect in treating double fractures of forearm in children. The method has advantages of safe operation, less injury, cheap expense, which can well obtain functional rehabilitation of patients.


Assuntos
Fixadores Externos , Fraturas do Rádio/cirurgia , Contenções , Fraturas da Ulna/cirurgia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Manipulação Ortopédica
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