Multiresidue screening of pesticides in Panax Ginseng C. A. Meyer by ultra-high-performance liquid chromatography with quadrupole time-of-flight mass spectrometry.

In this study, an efficient screening method based on a modified quick, easy, cheap, effective, rugged, and safe extraction method combined with ultra-high-performance liquid chromatography coupled to tandem quadrupole time-of-flight mass spectrometry was established for the determination of 90 pesticides residues in Panax Ginseng. The accuracy of the method was then verified by analyzing the false positive rate and the screening detection limit in Ginseng. The results revealed that the screening detection limit of 33 of 90 pesticide residues were 0.01 mg·kg-1 , 22 species were 0.05 mg·kg-1 , 11 species were 0.10 mg·kg-1 , 8 species were 0.20 mg·kg-1 , and another 16 species were greater than 0.20 mg·kg-1 . A total of 73 pesticides were ultimately suitable to be practically applied for rapid analysis of pesticide residues in Ginseng. Finally, the established method was used to analyze the pesticide residues in 35 Ginseng samples available on the market. And the residual of dimethomorph, azoxystrobin, tebuconazole, and pyraclostrobin was relatively severe in Ginseng samples. This work expanded the range of pesticides detected and provided a rapid, effective method for pesticides screening in Ginseng.

Comprehensive characterization of in vivo metabolic profile of Polygalae radix based on ultra-high-performance liquid chromatography-tandem mass spectrometry.

In this study, a novel analysis strategy for progressively targeted screening and characterization of drug ingredients from in vitro to in vivo was proposed based on ultra-high performance liquid chromatography-tandem mass spectrometry for comprehensive characterization of in vivo metabolic profile of Polygalae radix (PR). First, an in vitro chemical profile of PR was described with the assistance of UNIFI™ software. The characteristic neutral small molecule losses were summarized to distinguish different chemical structures in the PR extract. Second, the in vitro intestinal microflora metabolism model was applied to describe an in vitro metabolic profile of the main ingredients of PR. The metabolic rule and metabolites were integrated for subsequent targeted screening of metabolites in vivo. Finally, an integrated strategy was established and applied to screen and characterize the major absorbed components in vivo, including blood, urine, brain, feces, and liver, based on the prototypes and metabolic rules obtained in vitro. As a result, in vitro and in vivo metabolic profiles of PR were effectively depicted. A total of 136 compounds were isolated and identified from the crude extract in vitro, and 12 compounds were reported for the first time based on the proposed fragmentations. A total of 13, 32, and 3 compounds were identified and characterized in the dosed plasma, liver, and brain, respectively. A total of 40 and 73 compounds were identified in urine and feces, respectively. This strategy not only provided a comprehensive insight into the chemical and metabolic profiles of PR but also presented a new perspective for the discovery of new drugs for medicinal application.

A targeted strategy for analyzing untargeted mass spectral data to identify lanostane-type triterpene acids in Poria cocos by integrating a scientific information system and liquid chromatography-tandem mass spectrometry combined with ion mobility spectrometry.

Rapid structural identification of natural compounds in the crude extract of traditional Chinese medicine by conventional liquid chromatography-mass spectrometry is complex and challenging. In particular, it is difficult to distinguish and identify structural isomers. In this work, we proposed a novel strategy that combines a typical ultrahigh-performance liquid chromatography-multidimensional mass spectrometry approach and the post-processing UNIFI scientific information system to rapidly identify lanostane analogs and isomers in Poria cocos. First, this strategy requires setting up a high-resolution key MS database and an in-house compound library. Then, ultrahigh-performance liquid chromatography coupled with high-resolution tandem data-independent mass spectrometry and ion mobility mass spectrometry was used to acquire untargeted multidimensional mass spectral data. Finally, a new and reliable multidimensional MS analytical workflow was developed to targeted filter the acquired data based on an in-house compound library via the UNIFI™ software. As result, a total of 121 lanostane-type triterpene acids were identified by high-resolution molecular mass, fragment ions, and collision cross-section values. Eight triterpene acids were unambiguously identified by comparing the retention time and MS/MS data with those of reference compounds. Three compounds were detected and reported for the first time based on their neutral losses, characteristic ions, and fragmentation pathways compared with those of known compounds. We anticipate that such an analytical approach can be extended to rapidly screen and characterize other herbal medicine compounds with multiple isomers.

Studies on the chemical and intestinal metabolic profiles of Polygalae Radix by using UHPLC-IT-MSn and UHPLC-Q-TOF-MS method coupled with intestinal bacteria incubation model in vitro.

Polygala Radix (PR) is one of the most commonly used traditional Chinese medicines (TCM), but its effective materials are still not very clear. In order to solve the existing problems, the chemical and intestinal metabolic profiles of PR were analyzed via intestinal bacteria incubation model. An integrated analysis method combined ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF MS) method and ultra-high performance liquid chromatography with ion-trap multi-stage tandem mass spectrometry (UHPLC-IT-MSn) method was established. As a result, a total of 115 polygala compounds were identified from the PR extract. Moreover, 44 metabolites via intestinal microflora were characterized, of which three compounds were formed from xanthone C-glycosides, 25 compounds were formed from polygala saponins and 16 compounds were formed from oligosaccharide multi-esters. To our knowledge, the metabolites of the PR via intestinal microflora metabolism, especially polygala saponins, are the first reported in vitro. The obtained results would provide the methodological support for further studying the effective materials of the PR in vivo.

[Application of modern mass spectrometry in metabolism and pharmacokinetics of traditional Chinese medicine].

Modern mass spectrometry plays an important role in the study of metabolism and pharmacokinetics of traditional Chinese medicine due to its high sensitivity, high analysis speed and good stability. First, this article gives a brief introduction to the development of modern mass spectrometry techniques. Second, the application of modern mass spectrometry is summarized in the study of metabolism and pharmacokinetics of traditional Chinese medicine including in vitro and in vivo studies. In vitro research is reviewed with a focus on metabolism of intestinal bacteria and cytochrome P450 enzymes; in vivo research is covered mainly with a focuse on the application of microdialysis-MS, GC/LC-MS, new ambient mass spectrometry, and imaging mass spectrometry in metabolism and pharmacokinetics.

[High performance preparation and structural confirmation of lignans from Schisandrae chinensis fructus by using HSCCC combined with ESI-MSn method].

High-speed counter-current chromatography (HSCCC) was used to high performance separate and prepare lignans from Schisandrae chinensis fructus. The solvent system is composed of n-hexane-ethyl acetate-methanol-water (9 : 1 : 5 : 5) and n-hexane-ethyl acetate-methanol-water (9 : 1 : 9 : 5), speed is at 900 r.min-1, and flow rate is at 2.0 mL.min-1. Five fractions from Schisandrae chinensis fructus extract were separated and prepared with one HSCCC process. They were identified as schisandrin, gomisin J, schisandrol B, schisantherin A and deoxyschizandrin by electrospray ionization-multiple tandem mass spectrometry (ESI-MSn), respectively. Their contents were obtained in 98.74%, 94.32%, 99.53%, 94.23% and 98.68% by ultra high performance liquid chromatography (UPLC), separately. The rapid and simple method can be applied for the preparation of lignans from Schisandrae chinensis fructus.

[The metabolic fingerprint of the compatibility of Radix Aconite and Radix Paeoniae Alba and its effect on CYP450 enzymes].

Using a UPLC-MS/MS (MRM) and cocktail probe substrates method, the metabolic fingerprint of the compatibility of Radix Aconite (RA) and Radix Paeoniae Alba (RPA) and its effect on CYP450 enzymes were investigated. These main CYP isoforms include CYP 1A2, CYP 2C, CYP 2E1, CYP 2D and CYP 3A. Compared with the inhibition effect of RA decoctions on CYP450 isoforms, their co-decoctions of RA and RPA with different proportions can decrease RA' inhibition on CYP3A, CYP2D, CYP2C and CYP1A2, but can not reduce RA' effect on CYP2E1. The metabolic fingerprints of RA decoction and co-decoctions with different proportions of RPA in CYP450 of rat liver were analyzed by UPLC-MS. Compared with the metabolic fingerprints of RA decoction, the intensity of diester-diterpenoid aconitum alkaloids decreased significantly, while the intensity of monoester-diterpenoid alkaloids significantly increased in the metabolic fingerprints of co-decoctions of RA and RPA. The results suggest that RA coadministration with RPA increased the degradation of toxic alkaloid and show the effect of toxicity reducing and efficacy enhancing.

Effect of 20(S)-ginsenoside Rg3 on streptozotocin-induced experimental type 2 diabetic rats: a urinary metabonomics study by rapid-resolution liquid chromatography/mass spectrometry.

RATIONALE: 20(S)-ginsenoside Rg3 is an active component of Panax ginseng. It is known that 20(S)-ginsenoside Rg3 has a protective effect against hyperglycemia, obesity and diabetes in vivo, but the precise mechanisms of these actions have not yet been entirely elucidated. METHODS: A urinary metabonomics method based on rapid-resolution liquid chromatography/mass spectrometry (RRLC/MS) was developed to investigate the effect of 20(S)-ginsenoside Rg3 on type 2 diabetic rats. RESULTS: With multivariate statistical analysis, a clear separation between type 2 diabetic rats and those treated with 20(S)-ginsenoside Rg3 was achieved. Six potential biomarkers were found and identified. CONCLUSIONS: This work shows that the mechanism of the effect of 20(S)-ginsenoside Rg3 on type 2 diabetes may be involved with the regulation of nucleic acid metabolism, energy metabolism and gut flora metabolism.

Studies on the stability of diester-diterpenoid alkaloids from the genus Aconitum L. by high performance liquid chromatography combined with electrospray ionisation tandem mass spectrometry (HPLC/ESI/MSn).

The stability of diester-diterpenoid alkaloids (DDA) from plants of the genus Aconitum L. has been studied in different solvents and pH buffers. The HPLC/ESIMS method for analysing the concentration of DDA was established and DDA's decomposition products were elucidated by HPLC/ESI-MS/MS(n). In different solvents, e.g. dichloromethane, ether, methanol and distilled water, the decomposition pathways of DDA are quite different and their difference in stabilities depends on the difference of their structures, in which substituents at the N atom and substituents at C-3 are different. The pyrolytic products of DDA, such as deacetoxy aconitine-type alkaloids, have been observed in the above solvents, whereas 8-methoxy-14-benzoyl aconitine-type alkaloids have been obtained only in methanol. Furthermore, the experimental results demonstrate that the stability of DDA depends on pH values of the buffer. Aconine as hydrolysate has been only found in pH 10.0 buffer, and the other hydrolysates and the pyrolyzates of DDA, such as benzoylaconine and deacetoxy aconitine, have been observed in all pH aqueous solutions. The decomposition pathways of DDA in buffers are related to the substituent on the C-3 position. The decomposition pathway of aconitine is similar to that of mesaconitine, but different from that of hypaconitine.

[Analysis of aconite alkaloids in the combination of radix aconiti lateralis preparata with different herbs by ESI-MS spectrometry].

The method was established study the influence of different herbal combination with Radix Aconiti in the traditional medical formulae on content of the aconite alkaloids, for elucidating the scientific basis of reducing the toxicity of aconite in traditional Chinese medical formulation. The samples for ESI-MS study were prepared by decocting a mixture of Radix Aconiti Lateralis Preparata ( RALP) with Radix Glycyrrhizae Preparata (RGP) , Radix Paeoniae Alba ( RPA) , Rhizoma Zingiberis (RZ) or Radix Et Rhizoma Rhei ( RERR) , separately, and extracting the residue of the above mentioned mixtures after decocting. The diester-diterpenoid alkaloids (DDAs) was lower in the herb couples of RALP-RGP, RALP-RPA, RALP-RZ and RALP-RERR, and lipo-alkaloids was increased in the herb couples of RALP-RGP, RALP-RPA and RALP-RZ. The reason of reducing toxic effect principle is that the components of RGP, RPA and RZ have ester-exchange reactions with DDAs in RALP to produce lipo-alkaloids of low toxicity in the decocting process of the herb couples. The combination of RALP-RERR can reduce the content of DDAs in decoction and residue due to the formation of water insoluble alkaloid compound.