Discovery of unreported ginkgolides of anti-PAF activity using characteristic ion and neutral loss recognition strategy in Ginkgo biloba L.

Ginkgolides are the most important bioactive components of Ginkgo biloba L, of which ginkgolide B has been successfully developed and marketed as a drug. The reported ginkgolides are very rare and exhibit a complex matrix due to the chemodiversity of Ginkgo biloba L. Herein, the global profile of characteristic ion and neutral loss recognition strategy were used for to discover eight undescribed ginkgolides, very rare cyclohexane ginkgolides R-V, ginkgolides D-F, and eight known ginkgolides. These ginkgolides were target isolated and identified using high-resolution mass spectrometry, nuclear magnetic resonance spectroscopy, and X-ray crystallography. The undescribed and known ginkgolides exhibited antiplatelet aggregation activities. In particular, compounds U and D had IC50 values of 2.20 ± 0.15 and 6.50 ± 0.87 µM, respectively. This study has enriched the known structural diversity of ginkgolides and extended the application of mass spectrometry to the global profiling of natural products present in Ginkgo biloba L. Moreover, it could help chemists rapidly discover unreported compounds from a complex matrix.

2,4-dinitrophenylhydrazine capturing combined with mass defect filtering strategy to identify aliphatic aldehydes in biological samples.

Aliphatic aldehydes are toxic substances that correlate with the onset of many diseases. However, up to date, the methods to identify aliphatic aldehydes in biological samples are less selectivity and/or robustness. In this study, a strategy based on 2,4-dinitrophenylhydrazine (DNPH) capturing combined with mass defect filtering (MDF) was established and validated to identify aliphatic aldehydes in two biological samples (serum of immunosuppressed rats and oxidative damaged cells). Firstly, the mass spectrometric characteristic ions (m/z 163.01, 163.02 and 191.04) and fragmentation pathways of aldehyde-DNPHs were acquired through analyzing the standard references. Then, biological samples were derivatized by DNPH, a routine reagent, and subsequently assessed on an ultra-performance liquid chromatography coupled time-of-flight mass spectrometry (UPLC-QTOF-MS/MS). Thirdly, the raw chromatogram was processed by MDF method to obtain interference-free chromatogram. Fourthly, the aldehyde-DNPHs were characterized through investigating the mass spectrometric information of each peak referred to the identified characteristic ions and fragmentation pathways. Finally, 6 and 8 aliphatic aldehydes were exclusively identified in serum of immunosuppressed rats and supernatant of oxidative damaged cells. Among which, propanal and butanal were positively correlate with immunosuppression, while formalin was more relevant to oxidative stress. The results demonstrated that the established strategy could robustly characterize the aliphatic aldehydes in biological samples, which would be helpful to evaluate the physical conditions of subjects.

[Study on fragmentation patterns of coumarins in Notopterygium inchum with ultrahigh performance liquid chromatography combined with quadrupole time-of-flight mass spectrometry].

To demonstrate the fragmentation patterns of simple coumarins furanocourmarin(C_7-C_8), furanocourmarin(C_6-C_7) and dihydrofuran coumarin by mass spectrometry, with fraxin, scopoletin, isopsoralen, pimpinellin, isoimperatorin, notopterol and noda-kenin as study subjects, so as to provide a basis for rapid identification of compounds in different subtypes of coumarins. Ultrahigh performance liquid chromatography combined with quardrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was implemented in both positive and negative ion modes. Masslynx software was employed to provide the elemental constituents of each detected ion based on its accurate molecular weight. Chemdraw 2014 was used to cultivate mass number of each inferred structure. The fragment pattern of each compound was determined based on the structures inferred from all the relevant ions. And the patterns were drawn by Chemdraw 2014. The deviation between the calculated molecular weight of the inferred structure and the detected value of the ions was used to assess the correctness of the inferred structures in the fragmentation patterns. The results showed that with UPLC-Q-TOF, neutral loss of CO_2 and CO was reflected in lactone and furan skeletons from the courmarin structure. An even mass was attributed to the loss of an odd number of methyl radicals from compounds with a methoxy substituent. Furanocourmarin(C_7-C_8) produced a protonated molecular ion([M+H]~+), while the other courmarin subtypes produced either a sodium adduct of the molecular ion([M+Na]~+) or a sodium adduct of the molecular ion([M+Na]~+) with a protonated molecular ion([M+H]~+). The m/z 203.03 was a diagnostic ion for furanocourmarin(C_6-C_7), and the m/z 147.04 was supplementary evidence for furanocourmarin(C_6-C_7) identification. The characteristic ion of furanocourmarin(C_7-C_8) was m/z 131.05, while m/z 187.04 was the characteristic ion of dihydrofuran coumarin. The m/z 203.03 ion for furanocourmarin(C_7-C_8) was pretty weak. In negative ion mode, furanocourmarin(C_7-C_8) did not have any signals that were different from the other subtypes of courmarins. The fragmentation patterns in negative ion mode for the other subtypes of courmarins were similar to those in positive ion mode. Four types of fragmentation patterns were identified as forcourmarins from Notopterygium inchum. This study provides the basis for the rapid identification of courmarin subtypes by mass spectrometry.

Study on fragmentation patterns of coumarins in Notopterygium inchum with ultrahigh performance liquid chromatography combined with quadrupole time-of-flight mass spectrometry / 中国中药杂志

To demonstrate the fragmentation patterns of simple coumarins furanocourmarin(C_7-C_8), furanocourmarin(C_6-C_7) and dihydrofuran coumarin by mass spectrometry, with fraxin, scopoletin, isopsoralen, pimpinellin, isoimperatorin, notopterol and noda-kenin as study subjects, so as to provide a basis for rapid identification of compounds in different subtypes of coumarins. Ultrahigh performance liquid chromatography combined with quardrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was implemented in both positive and negative ion modes. Masslynx software was employed to provide the elemental constituents of each detected ion based on its accurate molecular weight. Chemdraw 2014 was used to cultivate mass number of each inferred structure. The fragment pattern of each compound was determined based on the structures inferred from all the relevant ions. And the patterns were drawn by Chemdraw 2014. The deviation between the calculated molecular weight of the inferred structure and the detected value of the ions was used to assess the correctness of the inferred structures in the fragmentation patterns. The results showed that with UPLC-Q-TOF, neutral loss of CO_2 and CO was reflected in lactone and furan skeletons from the courmarin structure. An even mass was attributed to the loss of an odd number of methyl radicals from compounds with a methoxy substituent. Furanocourmarin(C_7-C_8) produced a protonated molecular ion([M+H]~+), while the other courmarin subtypes produced either a sodium adduct of the molecular ion([M+Na]~+) or a sodium adduct of the molecular ion([M+Na]~+) with a protonated molecular ion([M+H]~+). The m/z 203.03 was a diagnostic ion for furanocourmarin(C_6-C_7), and the m/z 147.04 was supplementary evidence for furanocourmarin(C_6-C_7) identification. The characteristic ion of furanocourmarin(C_7-C_8) was m/z 131.05, while m/z 187.04 was the characteristic ion of dihydrofuran coumarin. The m/z 203.03 ion for furanocourmarin(C_7-C_8) was pretty weak. In negative ion mode, furanocourmarin(C_7-C_8) did not have any signals that were different from the other subtypes of courmarins. The fragmentation patterns in negative ion mode for the other subtypes of courmarins were similar to those in positive ion mode. Four types of fragmentation patterns were identified as forcourmarins from Notopterygium inchum. This study provides the basis for the rapid identification of courmarin subtypes by mass spectrometry.

Strategy for rapid screening of antioxidant and anti-inflammatory active ingredients in Gynura procumbens (Lour.) Merr. based on UHPLC-Q-TOF-MS/MS and characteristic ion filtration.

Gynura procumbens (Lour.) Merr. is traditionally used as a raw material for making dumplings or steamed stuffed buns, and its fresh leaves are boiled with water for tea. Herein, we established an ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) combined with characteristic ion filtration (CIF) strategy to rapidly screen active ingredients with antioxidant and anti-inflammatory properties in G. procumbens. This strategy involved screening the active part of G. procumbens using antioxidation and anti-inflammatory activity assays; discovering the active compounds by speculating on the active site's chemical composition by UHPLC-Q-TOF-MS/MS plus CIF; and verifying the active compounds' activities. The ethyl acetate extract (EEAF) of G. procumbens was the major active site. Eighty-one compounds were identified from the EEAF using UHPLC-Q-TOF-MS/MS plus CIF. Furthermore, polyphenols such as cynarine, isochlorogenic acids A and isochlorogenic acids C have excellent antioxidizing and anti-inflammatory activities. This study provides a practical strategy for rapid in vitro screening of the antioxidizing and anti-inflammatory activities of traditional vegetables and herbs and identification of active ingredients.

Application of multifold characteristic ion filtering combined with statistical analysis for comprehensive profiling of chemical constituents in anti-renal interstitial fibrosis I decoction by ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap high resolution mass spectrometry.

A Chinese herbal formula of Anti-Renal Interstitial Fibrosis I Decoction (ARIF I) is composed of Eucommia ulmoides Oliv., Scutellaria baicalensis Georgi, and Rheum. officinale Baill., and it has been used for the treatment of chronic kidney disease for many years. However, the comprehensive chemical analysis of the formulated ARIF I has yet to be clarified. In this study, an ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap high resolution mass spectrometry (UHPLC/Q-orbitrap HRMS) method executed in full scan/data-dependent MS2 (full MS/dd-MS2) mode has been established in negative ion mode to analyze the major chemical constituents in ARIF I as well as in its three constituent herbs. To rapidly and efficient identify these compounds, we employed a combination of statistical analysis of the MS2 data and fragmentation pathway method to screen for elementary characteristic ions and sub-characteristic ions. Then, we applied multifold characteristic ion filtering to comprehensively profile ARIF I extract chemical constituents with diverse structures. A total of 360 compounds, including anthraquinones, sennosides, galloyl glucoside derivatives, catechin and its derivatives, flavonoids, iridoids, phenylpropanoids, lignan, organic acid, and other compounds were rapidly identified or tentatively characterized by multifold characteristic ion filtering based on their accurate mass spectra (within 5 ppm error) and structure types or by comparison with reference standards. All the ARIF I compounds were also detected in the individual constituent herbs. This study provides a basis for further pharmacokinetic studies of ARIF I and may help in the discovery of new chemical drugs to treat chronic kidney disease. This study also provides a more efficient approach for the screening of appropriate characteristic ions, and a practical strategy for the detection of the types of compounds identified in this study in other herbal medicines.

Application of characteristic ion filtering with ultra-high performance liquid chromatography quadrupole time of flight tandem mass spectrometry for rapid detection and identification of chemical profiling in Eucommia ulmoides Oliv.

Efficient targeted identification of chemical constituents from traditional Chinese medicine is still a major challenge. In this study, we used a characteristic ion filtering strategy to characterize compounds of Eucommia ulmoides Oliv. by ultra-high performance liquid chromatography quadrupole time of flight tandem mass spectrometry (UHPLC-ESI-Q-TOF-MS/MS). By using the ion filtering approach, target constituents of Eucommia ulmoides Oliv. were easily tentatively identified from the enormous LC/MS data set. The strategy consisted of the following three steps: 1) To establishing a characteristic ion database by diagnostic product ions or neutral loss fragments; 2) To evaluate the structural information of the compounds by high-resolution diagnostic characteristic ion filtering; 3) To confirm the different classes by chemical profiling according to their MS/MS spectra. In this study, characteristic ions are summarized as five major groups of compounds in Eucommia ulmoides Oliv. In total, 113 compounds were tentatively identified, including 23 potentially novel compounds. The results form a foundation for the quality control and chemical basis of Eucommia ulmoides Oliv.

A new, quick, highly sensitive ultramicro-analysis method for the identification of fructose removed from fructofuranosyl-containing gluco-oligosaccharides by ESI-CID-MS/MS.

An efficient, highly sensitive, and ultramicroscale analytical method for the identification of fructose removed from fructofuranosyl-containing gluco-oligosaccharides, including malto-oligosyl fructofuranosides and oligomeric (1→2)-α-D-glucopyranosyl-(1→2)-ß-D-fructofuranosides by ESI-CID-MS/MS has been developed with proven applications far superior to the existing method using NMR. With the established principle of diagnostic fragmentation by ESI-CID-MS/MS, the terminal saccharide (either glucose or fructose) can be readily and unambiguously determined at high sensitivity without a tedious derivatization process. Detection of the A-type fragmentation (0,4)A-h type ion, and (0,2)A type ion are useful as a diagnostic fragmentation tool to identify whether fructose terminal is removed from oligosaccharides. It will facilitate the efficient production of suitable oligosaccharide microarrays crucial for studies on carbohydrate-protein interaction in seeking functional carbohydrates.

Determination of ephedrine and pseudoephedrine in MAHUANG TANG~* by GC-MS and effect of compatible medicinal herbs on concentration of components in decoction / 中草药

Object To establish a quantitative method for ephedrine and pseudoephedrine in the aqueous decoctions of MAHUANG TANG (ADMHT) by GC MS, and to determine the content of the two components in decoctions of the different recipes consisted of Herba Ephedrae, and other herbs by using the quantitative method will be established, so as to study the effect of compatible medicinal herbs on the release of the two components in Herba Ephedrae to decoctions Methods The quantitative method by the help of characteristic ion was used in GC MS Results The content of ephedrine and pseudoephedrine in decoction prepared from Herba Ephedrae and Semen Armeniacae Amarum evidently decreases, the content of two components in decoction prepared from Herba Ephedrae and Ramulus Cinnamomin evidently increases, the content of two components in decoction prepared from Herba Ephedrae and Radix Glycyrrhizae has no obvious change, as compared with that of two components in decoction from Herba Ephedrae alone Conclusion The method is good in the aspect of separable effect, sensitivity and reproducibility The method not only can quantify the two components, but also provide the bases of quality control for the pharmacokinetic study and therapeutic detection of Herba Ephedra recipes