Analysis of Differences in Secondary Metabolites from Dendrobium nobile Stems Cultivated on Epiphytic Rocks in Different Growth Years Based on Metabolomics / 中国实验方剂学杂志

ObjectiveTo study the changing characteristics of secondary metabolic compounds accumulated in Dendrobium nobile stems at different growth years， a simulated wild stone plant， in order to provide a theoretical basis for rational planning of the harvesting period of D. nobile. MethodUltra-high performance liquid chromatography-mass spectrometry（UPLC-MS/MS） was used to detect and analyze the secondary metabolites in the stems of 1-year-old， 2-year-old， and 3-year-old D. nobile. The mass spectrometry data were processed using Analyst 1.6.3 software， and all samples were subjected to principal component analysis（PCA）， cluster heat map analysis， partial least squares-discriminant analysis（PLS-DA）， and differential secondary metabolites were screened based on variable importance in projection（VIP） values>1， fold change（FC）≥2 and FC≤0.5. Then differential secondary metabolites were identified based on relative molecular weight， fragmentation ions and mass spectrometry database， and enriched pathways were identified based on the Kyoto Encyclopedia of Genes and Genomes（KEGG） database. ResultA total of 1 317 secondary metabolites were identified in the stems of D. nobile at three growth stages， with flavonoids， phenolic acids， alkaloids and terpenoids accounting for 76.55% of the total. Compared with the 1-year-old stems of D. nobile， 289 differential secondary metabolites were identified in the 2-year-old stems， of which 255 were up-regulated and 34 were down-regulated， 682 differential secondary metabolites were identified in the 3-year-old stems， of which 502 were up-regulated and 180 were down-regulated. Compared to the 2-year-old stems， the 3-year-old stems had 602 differential secondary metabolites， with 405 up-regulated and 197 down-regulated. As the growth stage of D. nobile increased， the top 10 up-regulated differential metabolites mainly included flavonoids， phenolic acids， phenylpropanoids and terpenoids， such as kaempferol derivatives， asperulosidic acid， apigenin derivatives， chrysoeriol derivatives， isorhamnetin derivatives， taxifolin derivatives， quercetin derivatives. KEGG enrichment analysis showed significant enrichment of secondary metabolites in the flavonoid biosynthesis， flavone， and flavonol biosynthesis， secondary metabolite biosynthesis， and phenylpropanoid biosynthesis pathways with the increase of growth years. ConclusionWith the increase of the growth years， the levels of secondary metabolites such as flavonoids， phenolic acids， phenylpropanoids and terpenoids in the wild-grown D. nobile have been significantly enhanced. In practical production， grading based on different growth years can be carried out to improve the medicinal and economic values of D. nobile.

Metabonomic Analysis of Wenfei Huaxian Granules Against Idiopathic Pulmonary Fibrosis in Mice / 中国实验方剂学杂志

ObjectiveTo investigate the changes of differential metabolites in the serum of mice at different stages of bleomycin sulfate（BLM）-induced pulmonary fibrosis modeling and administration， and the mechanism of Wenfei Huaxian granules（WHG）against idiopathic pulmonary fibrosis. MethodMice were randomly divided into control group， control group of 14 days， model group， model group of 14 days， low-dose WHG group and high-dose WHG group. BLM（0.04 U per mouse）was injected into the trachea of mice in the model group， model group of 14 days， low-dose WHG group and high-dose WHG group， and sterile normal saline was injected into the trachea of mice in the control group and control group of 14 days. Mice of low-dose WHG group and high-dose WHG group were given different doses of WHG by gavage every day after injection of BLM， and mice of control group， control group of 14 days， model group and model group of 14 days were given sterile water by gavage every day. The peripheral blood of mice in the control group of 14 days and model group of 14 days were taken to prepare serum after injection of BLM for 14 days， and the peripheral blood and other materials of mice in the other groups were taken after continuous administration for 28 days. The bronchoalveolar lavage fluid（BALF）was collected for leucocyte differential count， the pathological examination and hydroxyproline（HYP）content determination of lung tissues of mice were performed， and the small molecule metabolites in serum samples of mice in each group were determined by ultra-high performance liquid chromatography-mass spectrometry（UHPLC-MS）. Principal component analysis（PCA）and orthogonal partial least squares-discriminant analysis（OPLS-DA）were conducted to screen differential metabolites and their biological functions were analyzed. ResultCompared with the control group， a large number of continuous fibrotic foci appeared in the lung tissue of mice in the model group， the alveolitis score， fibrosis degree score and HYP content increased significantly（P<0.01）， and the total number of leukocytes， macrophages and lymphocytes in BALF increased significantly（P<0.05）. A total of 33 differential metabolites were screened between the control group of 14 days and model group of 14 days， mainly lipid metabolites， which were mainly involved in oxidative damage and inflammatory process. A total of 34 differential metabolites， mainly amino acid metabolites， were screened between the control group and model group， mainly involving nucleic acid damage and inflammatory process. Compared with the model group， the HYP content， fibrosis score and alveolitis score in the lung tissue of mice from high-dose WHG group decreased significantly（P<0.05， P<0.01）， and the total number of lymphocytes in BALF decreased significantly（P<0.05）. Compared with the model group， 27， 40 differential metabolites were identified in the serum of mice from the low-dose WHG group and high-dose WHG group separately. There were totally 9 common differential metabolites between the model group and low-dose WHG group/high-dose WHG group， which mainly involved in the metabolic pathways of inflammation related lipids metabolism， arginine and tryptophan metabolism， and the change trends in low-dose WHG group and high-dose WHG group were significantly back-regulated compared with the model group. ConclusionWHG can alleviate BLM-induced pulmonary fibrosis， collagen deposition and inflammatory reaction in mice， and its anti-fibrotic effect may be related to the adjusting of inflammatory factors， nitric oxide and oxidative stress related metabolic pathways.

Analysis of Mechanism of Yishen Huashi Granules for Improving Diabetic Nephropathy Based on Metabonomics and Transcriptomics / 中国实验方剂学杂志

ObjectiveIn this study， based on ultra-high performance liquid chromatography-mass spectrometry（UHPLC-MS/MS） and high-throughput transcriptome sequencing technology（RNA-seq）， we investigated the mechanism of Yishen Huashi granules in regulating serum metabolites and renal messenger ribonucleic acid（mRNA） expression to improve diabetic kidney disease（DKD）. MethodSD rats were randomly divided into normal group ， model group and Yishen Huashi granules group， with 8 rats in each group. The rat model of DKD was established by intraperitoneal injection of streptozotocin. Yishen Huashi granules group was given 5.54 g·kg-1·d-1 of Yishen Huashi granules by gavage， and the normal group and the model group were given the same amount of normal saline for 6 weeks. During the experiment， the body weight and blood glucose of rats were monitored， and the rats were anesthetized 24 hours after the last administration， blood was collected from the inferior vena cava， serum was separated， and renal function， blood lipid， and inflammatory indicators were detected. Kidney tissue of rats was fixed in neutral paraformaldehyde， and stained with hematoxylin-eosin（HE）， Masson and periodic acid-Schiff（PAS） to observe the renal pathological changes. UHPLC-MS/MS and RNA-seq were used to identify the changes of serum metabolism and the differences of renal mRNA expression， and real time fluorescence quantitative polymerase chain reaction（Real-time PCR） and Western blot were used to detect the differential mRNA and protein expression in renal tissue to explore the common expression mechanism. ResultCompared with the normal group， rats in the model group showed a decrease in body weight， a significant increase in blood glucose， urinary microalbumin to urinary creatinine ratio（UACR）， blood urea nitrogen（BUN）， cystatin-C（Cys-C）， β2-microglobulin（β2-MG）， interleukin-6（IL-6）， triglyceride（TG） and total cholesterol（TC）， and a significant decrease in total superoxide dismutase（T-SOD）（P<0.01）. After the intervention of Yishen Huashi granules， all the indexes were improved to different degrees in rats（P<0.05， P<0.01）. Compared with the normal group， the model group showed renal mesangial stromal hyperplasia， fibrous tissue hyperplasia and tubular vacuolar degeneration. Compared with the model group， the renal pathology of rats in Yishen Huashi granules group was improved to a certain extent. A total of 14 target metabolites and 96 target mRNAs were identified， the target metabolites were mainly enriched in 20 metabolic pathways， including sphingolipid metabolism， glycerophospholipid metabolism， and the biosynthesis of phenylalanine， tyrosine and tryptophan. The target mRNAs were enriched to obtain a total of 21 differential mRNAs involved in the TOP20 pathways closely related to glycolipid metabolism. A total of 6 pathways， glycerophospholipid metabolism， arachidonic acid metabolism， purine metabolism， primary bile acid biosynthesis， ascorbic acid and uronic acid metabolism， and galactose metabolism， were enriched by serum differential metabolites and renal differential mRNAs， among them， there were 7 differential metabolites such as phosphatidylethanolamine（PE） and 7 differential mRNAs such as recombinant adenylate cyclase 3（ADCY3）. Seven differential metabolites had high predictive accuracy as verified by receiver operating characteristic（ROC） curve， and the results of Real-time PCR and Western blot were highly consistent with the sequencing results. ConclusionYishen Huashi granules can reduce UACR， BUN and other biochemical indexes， correct the disorder of glucose and lipid metabolism， and improve renal function of DKD rats. And its mechanism may be related to the regulation of the level of PE and other blood metabolites， and expression of Phospho1 and other mRNAs in the kidney， of which six pathways， including glycerophospholipid metabolism， may play an important role.

Exploration on Syndrome Types and Metabolic Markers of Rat Model with Heart Failure Caused by Transverse Aortic Constriction Based on Theory of Correspondence of Prescription and Syndrome / 中国实验方剂学杂志

ObjectiveTo observe the difference in the efficacy of three kinds of traditional Chinese medicine （TCM） injections on rat model of heart failure induced by transverse aortic constriction （TAC）， explore the TCM syndrome of the model based on the theory of correspondence of prescription and syndrome， and reveal the biological basis of prescription-syndrome from the perspective of metabolism. MethodRats were treated with TAC for modeling and were divided into Shenmai injection group （6.0 mL·kg-1）， model group， Danhong injection group （6.0 mL·kg-1）， Shenfu injection group （6.0 mL·kg-1） and trimetazidine group （10 mg·kg-1）， and sham operation group was set up as control. After drug intervention for 15 days， echocardiography， serum N-terminal pro-brain natriuretic peptide （NT-proBNP） and myocardial histopathological staining were performed for each group， so as to compare the efficacy to select the effective injection. Colorimetry was used to detect the serum glucolipid metabolism after the intervention of the effective injection， and ultra high performance liquid chromatography-mass spectrometry was used to observe the metabolites and related metabolic pathways in myocardial tissue. ResultCompared with the sham operation group， the left ventricular ejection fraction （LVEF） and left ventricular fractional shortening （FS） in the model group decreased （P<0.01）， while the left ventricular end-diastolic diameter （LVIDd）， left ventricular internal diameter at end-systole （LVIDs） and NT-proBNP level increased （P<0.01）. Compared with model group， LVEF and FS increased （P<0.01）， LVIDd， LVIDs and NT-proBNP level decreased （P<0.05， P<0.01） in Danhong injection group， NT-proBNP level in Shenfu injection group decreased （P<0.05）， LVIDd and NT-proBNP level increased （P<0.05， P<0.01） in Shenmai injection group， in trimetazidine group， LVEF and FS increased （P<0.01）， while LVIDs and NT-proBNP level decreased （P<0.05， P<0.01）. Serum glucose， low-density lipoprotein cholesterol and high-density lipoprotein cholesterol levels in Danhong injection group and trimetazidine group were adjusted by callbacks （P<0.01， P<0.05）. There were the callback of 9 myocardial metabolites in Danhong injection group， including glycine， serine and threonine metabolism， glyoxylate and dicarboxylate metabolism， glycerol phospholipid metabolism. There were the callback of 10 myocardial metabolites in trimetazidine group， including glycerol phospholipid metabolism. ConclusionThe efficacy of Danhong injection on heart failure model induced by TAC is significant and superior to Shenfu injection and Shenmai injection， suggesting that the model is closely related to heart-blood stasis. The biological mechanism of Danhong injection interfering with the model involves regulating the metabolic disorder of lipid， glucose， amino acid and butyric acid.

Detection of Exogenous γ-Hydroxybutyric Acid in Rat Blood Exosomes / 法医学杂志

OBJECTIVES@#To find a method to distinguish exogenous gamma-hydroxybutyrate (GHB) from endogenous GHB by establishing ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS) based on exosome for quantitative detection of GHB in the rat blood.@*METHODS@#Adult male SD rats were divided into 1 h, 5 h, 10 h administration group and control group. After 1 h, 5 h and 10 h of single precursor of GHB gamma-butyrolactone (GBL) intraperitoneal injection in administration groups, 5 mL blood was collected from the abdominal aorta. Meanwhile, the control group was given a same dose of normal saline, and 5 mL blood was collected at 1 h. Among the 5 mL blood, 0.5 mL was directly detected by HPLC-MS after pretreatment, and exosomes were extracted from the remaining blood by differential centrifugation and detected.@*RESULTS@#The concentration of GHB in the control group was (87.36±33.48) ng/mL, and the concentration with administration at 1 h, 5 h and 10 h was (110 400.00±1 766.35) ng/mL, (1 479.00±687.01) ng/mL and (133.60±12.17) ng/mL, respectively. The results of exosome detection showed that no peak GHB signal was detected in the control group and the 10 h administration group, and the concentrations of GHB at 1 h and 5 h administration groups were (91.47±33.44) ng/mL and (49.43±7.05) ng/mL, respectively.@*CONCLUSIONS@#GHB was detected in blood exosome by UPLC-MS, which indicated that exogenous GHB could be detected in plasma exosomes, while endogenous GHB could not be detected, suggesting that this method may be used as a basis to determine whether there is exogenous drug intake.

Feasibility of the determination of plasma vardenafil level in rat by performance liquid chromatography-tandem mass spectrometry / 中华心血管病杂志

Objective: To develope and validate a reliable and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determination of vardenafil concentration in plasma of rat. Methods: Plasma samples of normal Sprague-Dawley rats were collected. A Phenomenex Synergi Polar-RP 80A column (2.0 mm×50 mm, 4 µm) was used. Column temperature was set at 30 ℃. Mobile phase A was 0.1% formic acid in water; mobile phase B was 0.1% formic acid in acetonitrile. The flow rate was 0.4 ml/minutes. Quantitative determination was performed by electrospray ionization, operating in positive ion multiple reaction monitoring (MRM) mode. Cisapride was used as the internal standard. The feasibility of the method was evaluated by examining its specificity, linearity and quantitative range, precision and accuracy, matrix effects, and stability. Results: Under the selected chromatographic and mass spectrometry conditions, the monitoring ions of vardenafil and internal standard were mass-to-charge ratio（m/z) 489.3/151.2 and 466.4/234.2, the retention times of vardenafil and internal standard were 2.62 and 2.80 minutes, respectively, and the peak shape was satisfactory. The method has good linearity in the concentration range of 0.2-200 ng/ml. The intra-batch precision (%CV) and accuracy (%DEV) of vardenafil were 1.5%-9.7% and -6.8%-6.6%, respectively. The inter-batch precision and accuracy of vardenafil were 3.1% -8.4% and -3.7%-4.6%, respectively. In this sample processing method, the extraction recovery rate of vardenafil was obtained at range of 88.2%-104.6%, which met the requirements for the investigation of extraction recovery rate. In this sample processing method, the normalized matrix factor of each quality control concentration of vardenafil was 1.04, 0.85, and 1.04, and the coefficient of variation (%CV) was in the range of 1.7%-10.7%, which met the requirements for the investigation of matrix effects. Variations of short-term stability, long-term stability, and stability of 4 freeze-thaw cycles of vardenafil was within ±15%, and the coefficient of variation were within 5%. Conclusion: The high performance liquid chromatography-tandem mass spectrometry method established in this study is feasible for the measurement of concentration of vardenafil in rat plasma and this method has good specificity and high accuracy, and can be used to detect the concentration of vardenafil in rat plasma.

Investigation of Chemical Constituents and Sources of Zhishi Xiebai Guizhi Decoction by LC-MS/MS / 中国药学杂志

OBJECTIVE: To study the chemical constituents of Zhishi Xiebai Guizhi decoction and its single agent by high performance liquid chromatography-mass spectrometry to provide a scientific basis for the quality evaluation and control. METHODS: Agilent XDB-C18(4.6 mm×250 mm, 5 μm) column was used for HPLC analysis with acetonitrile-water as mobile phase by gradient elution. Using liquid chromatography-mass spectrometry technology to collect data in positive and negative ion mode, combined with literature reports, the main chemical components of Zhishi Xiebai Guizhi decoction were analyzed and identified. RESULTS: A total of 19 compounds were identified from Zhishi Xiebai Guizhi decoction. The main components are naringin, neohesperidin, etc. The main component types include alkaloids, steroidal saponins, glycosides, flavonoids, etc. CONCLUSION: This study comprehensively clarified the chemical composition of Zhishi Xiebai Guizhi decoction, and it has important reference value for the identification and quality evaluation of Zhishi Xiebai Guizhi decoction.

Primary research on components with anticomplement and antitussive activities from leave extracts of Chimonanthus nitens / 中草药

Objective: To investigate and analyze anticomplement and antitussive activities and the active ingredients of the extract of Chimonanthus nitens leaf. Methods: The classical anti-complement pathway and the concentrated ammonia-induced cough model was used to compare the activity of the different polar parts of C. nitens leaf, and the polar parts with anti-complement and antitussive activity were determined. A preliminary analysis of the chemical composition in activity extract was identified by high performance liquid chromatography-mass spectrometry. The main chemical components in the C. nitens leaf of antitussive and antibody activity were also evaluated. Results: The ethyl acetate extract of C. nitens leaf had both anti-complement and antitussive effects. A total of 28 compounds were initially identified through mass spectrometry analysis. Kaempferol-3-O-rutinoside and kaempferol had both antitussive and anti-complement activities. Conclusion: The ethyl acetate extract of C. nitens leaf has good anti-complement and antitussive activities, and the mainly active ingredients in it were kaempferol-3-O-rutinoside and kaempferol that could be used as quality-controlling chemical markers.

Limitation standard of toxic aconitines in proprietary Chinese medicines using on-line extraction electrospray ionization mass spectrometry

Development of rapid analytical methods and establishment of toxic component limitation standards are of great importance in quality control of traditional Chinese medicine. Herein, an on-line extraction electrospray ionization mass spectrometry (oEESI-MS) coupled with a novel whole process integral quantification strategy was developed and applied to direct determination of nine key aconitine-type alkaloids in 20 proprietary Chinese medicines (APCMs). Multi-type dosage forms (, tablets, capsules, pills, granules, and liquid preparation) of APCM could be determined directly with excellent versatility. The strategy has the characteristics of high throughput, good tolerance of matrix interference, small amount of sample (∼0.5 mg) and reagent (∼240 μL) consumption, and short analysis time for single sample (<15 min). The results were proved to be credible by high performance liquid chromatography-mass spectrometry (LC-MS) and electrospray ionization mass spectrometry, respectively. Moreover, the limitation standard for the toxic aconitines in 20 APCMs was established based on the holistic weight toxicity (HWT) evaluation and the severally, and turned out that HWT-based toxicity evaluation results were closer to the real clinical applications. Hence, a more accurate and reliable APCM toxicity limitation was established and expected to play an important guiding role in clinics. The current study extended the power of ambient MS as a method for the direct quantification of molecules in complex samples, which is commonly required in pharmaceutical analysis, food safety control, public security, and many other disciplines.

Stability of hydroalcoholic extracts of two species of guaco; Mikania glomerata SPRENG. and Mikania laevigata SCHULTZ. (Asteraceae), by UHPLC-MS

It is important to study the stability of plant extracts used as active ingredients in phytotherapic medicine, as degradation of the active principles directly affects the efficacy and safety of these products. Therefore, a stability study of the hydroalcoholic extract of the species: Mikania glomerata and Mikania laevigata was conducted in order to determine the speed of degradation and shelf life of these extracts, which are incorporated in cough syrup in Brazil. Leaves of both species were dried in an oven or by lyophilization (freeze-dried). Hydroalcoholic extracts underwent both accelerated stability study of six months and long-term stability study for 12 months. Samples were stored at different temperatures and every three months were analysed by ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) to monitor their chemical profile, quantifying coumarin and chlorogenic acid. For all conditions of the study, a reduction of the content of the chemical marker of this species, coumarin, greater than 5% was observed, so a shelf life of two years cannot be assigned to the hydroalcoholic extracts of these species as observed in commercial extracts.

Determination of related genotoxic impurities in olmesartan medoxomil by HPLC-MS / 中国药科大学学报

@#The aim of this study was to establish a high performance liquid chromatography-mass spectrometry method for the determination of 5-(4′-(bromomethyl)-［1, 1′-biphenyl］-2-yl)- 1H-tetrazole(BBT1)and 5-(4′-(dibromomethyl)-［1, 1′-biphenyl］-2-yl)-1H-tetrazole(BBT2), which are two genotoxic impurities in olmesartan medoxomil. Chromatographic separation was based on an Agilent Zorbax Eclipse Plus C18(250 mm × 4. 6 mm, 5 μm)column using water(containing 0. 1% formic acid)- acetonitrile as mobile phase in gradient elution mode. Mass spectrometry was operated in positive ion mode. Selective ion monitors were set at m/z 315 for BBT1 and at m/z 395 for BBT2. Good linear correlations were observed in the range of 0. 009 4- 0. 561 0 μg/mL(r=0. 998)with the quantification limit at 9. 35 ng/mL and the detection limit at 3. 12 ng/mL for BBT1, and in the range of 0. 018 2- 0. 547 5 μg/mL(r=0. 999)with the quantification limit at 18. 25 ng/mL and the detection limit at 6. 08 ng/mL for BBT2. Furthermore, the average recoveries of the three spiked concentration level were 96. 5%(n=9, RSD=4. 8%)and 98. 0%(n=9, RSD=5. 1%)for BBT1 and BBT2, respectively. The proposed method is simple, specific and accurate, and quite suitable for the determination of BBT1 and BBT2 in olmesartan medoxomil.

Determination of 8 Kinds of Cephalosporins in Aquatic Products by Multi-walled Carbon Nanotubes Solid Phase Extraction-Ultra High Performance Liquid Chromatography-Mass Spectrometry / 分析化学

An ultra-high performance liquid chromatography-mass spectrometry ( UPLC-MS/MS) method was developed for the determination of 8 kinds of cephalosporins, cefoperazone, cefquinome, cefalonium, cefazolin, cefapirin, Ceftiofur, cefpirome and cefalexin, in edible parts of aquatic products. The samples were extracted with acetonitrile-water and cleaned up by multi-walled carbon nanotubes ( MwCNTs) SPE cartridge. All the target compounds were separated on an Acquity Xselect CSH C18 column with gradient elution by using acetonitrile and 0. 1% formic acid aqueous as eluent, and detected by UPLC-MS/MS under ESI+ ionization and MRM mode. Under optimized conditions, this method had a good linearity (R2≥0. 995) and the limits of quantification were in the range of 2-10 μg/kg ( S/N=10 ) . The recoveries of the method for the target compounds spiked at three different levels were 67. 3%-94. 2% with the relative standard deviations (RSDs) of 3. 3%-14%. The method had the characteristics of low cost, high accuracy and good precision, and could meet the requirements of cephalosporins determination.

Comprehensive monitoring of charge analysis and research of active pharmaceutical ingredients in Shedan-Chenpi tablet by high performance liquid chromatography-mass spectrometry / 国际中医中药杂志

Objective The monitoring of the feeding situation of active pharmaceutical ingredient in Shendan-Chenpi tablet by HPLC-MS/MS,and the content of sodium taurocholate and hesperidin.Methods Using ZORBAX Eclipse Plus C18(4.6 mm×250 mm, 5 μm)Column temperature 40 ℃, Mobile phase with acetonitrile-10 mmol/sodium acetate solution, using gradient elution program. Active ingredients were separated by HPLC, and the Electrospray Ionization Mass (ESI) source was applied and operated in the negative ion mode, and reactions ion monitoring mode(MRM) for quantitative analysis were selected. Results The proprietary Chinese medicine is judged by the prescription feeding process, through analysis and contrast of the medicinal materials, reference substance of primary mass spectrogram, secondary mass spectrogram of peak. The aurocholic acid sodium and hesperidin had a good linear relationship in 0.242×10-2-1.45×10-2μg(r=0.996 0), 0.688×10-2-10.30×10-2μg(r=0.999 2), and the precision test were 0.78% and 1.56%, and the recovery rate were 102%-103%,96%-109%. Conclusions The method was simple, accurate and reliable, high sensitive and fast. The comprehensive monitoring was applied to the Shedan-Chenpi tablet in feeding analysis and quality.

Determination of Tetrodotoxin in Marine Organisms by High Performance Liquid Chromatography-Mass Spectrometry and Cleaned up by Immunoaffinity Column / 分析化学

A method was developed for the determination of tetrodotoxin in marine organisms by high perfor-mance liquid chromatography-mass spectrometry with immunoaffinity column. The samples were extracted with 1% acetic acid methanol solution and diluted with phosphate buffer at pH 7-8. After cleaned up by immuno-affinity column, the samples were analyzed by LC-MS/MS and quantitatively determined by external standard method. The chromatographic separation was performed on an ACQUITY UPLC BEH Amide column with gradient elution by using acetonitrile and 5 mol/L ammonium acetate solution containing 0. 1% formic acid as mobile phase. Detection was carried out by electrospray positive ionization mass spectrometry in the multiple reaction monitoring mode. Linear ranges of TTX was in the range of 0. 3 -20. 0 μg/L with correlation coeffi-cient more than 0. 997. The quantification limit of the method was 0. 3 μg/kg. The recoveries of standard addition for tetrodotoxin were 88. 7%-102. 3%, and the relative standard deviation was 2. 0%-6. 4%. The method could be used to identify and quantify tetrodotoxin in marine organisms with satisfactory reproducibility and sensitivity.

Studies on the formation and synthetic mechanism of related substance G in potassium clavulanate production

The objective of this study was to investigate the formation and synthetic mechanism of related substance G in potassium clavulanate production. The impurity in the potassium clavulanate final product, with a retention time of 13.5 min, was confirmed as related substance G by high performance liquid chromatography-mass spectrometry/mass spectrometry. Related substance G analysis during the production of clavulanic acid showed that this impurity could be synthesized during fermentation, and the amount increased with the fermentation time. Studies on its synthetic mechanism showed that L-tyrosine and succinic acid were the precursors for biosynthesis of related substance G in vivo. The reaction was deduced to be catalyzed by an enzyme. The enzyme was a type of extracellular enzyme present in the fermentation supernatant.

O objetivo deste estudo foi investigar a formação e o mecanismo sintético da substância G relacionada na produção de clavulanato de potássio. A impureza do produto final clavulanato de potássio, com tempo de retenção de 13,5 min, foi confirmada como substância G relacionada por cromatografia líquida de alta eficiência-espectrometria de massas/espectrometria de massas. A análise da substância G relacionada durante a produção do ácido clavulânico mostrou que essa impureza poderia ser sintetizada durante a fermentação e que a quantidade aumenta com o tempo de fermentação. Estudos do seu mecanismo sintético mostraram que a L-tirosina e o ácido succínico foram os precursores in vivo para a biossíntese da substância G relacionada. Deduziu-se que a reação foi catalisada por uma enzima. A enzima foi do tipo extracelular, presente no sobrenadante da fermentação.

Separation of Cyclotetramethylenetetranitramine Synthetic Intermediates by Online Molecular Imprinted Solid Phase Extraction and Liquid Chromatography / 分析化学

An online solid phase extraction ( SPE ) coupled with high performance liquid chromatography (HPLC)-mass spectrometry (MS) method was developed for the separation of 1,3,5,7-tetraacetyl-1,3,5,7-tetraazacyclooctane ( TAT ) and 1 , 3 , 5-triacetyl-1 , 3 , 5-triazacyclohexane ( TRAT ) which are the synthetic intermediates of cyclotetramethylenetetranitramine ( HMX) . In this experiment, molecularly imprinted polymers with TAT as the template were used as SPE sorbents. PC HILIC column was employed in liquid chromatographic separation. The parameters of SPE-HPLC were optimized. Acetonitrile was selected as the loading solution with flow rate of 0. 1 mL/min. After flushed by ethyl acetate, the TAT adsorbed on SPE was eluted by methanol, which was also used as the mobile phase in HPLC separation. The mass spectrometry was coupled with HPLC to identify the corresponding peaks. Under the optimized conditions, the linear detection range of this method was 6. 0 mg/L to 500. 0 mg/L, with the detection limit of 1. 8 mg/L (3σ). The enriching factor was 400 times and TAT recovery was 79%–93% in the standard addition experiment.

Rapid Determination of N-Methylcarbamoyl Adduct in Hemoglobin of Workers Exposed to N,N-Dimethylformamide by Ultra High Performance Liquid Chromatography-Mass Spectrometry / 分析化学

A rapid analytical method was developed for the determination of N-methylcarbamoyl adduct in Hemoglobin of workers exposed to N,N-dimethylformamide by ultra high performance liquid chromatography-mass spectrometry ( UPLC/MS/MS). About 0. 1 g of hemoglobin sample, 40 μmol/L of 3-methyl-5-isopropylhydantoin (MIH) as the internal standard and 4. 75 mL of HCl-acetic acid (2∶1, V/V) were added in the centrifuge tube, and mixed for 3 min. Then the tube was heated in boiling water bath for 1h. After cooling down, 200 μL of the mixture and 600 μL of formic acid-acetonitrile (1%) were added into 96-well extract plate. The vacuum pump pressure was controlled to make the sample collection elute within 2-4 min.The purified collection was transferred into the sample vial, and 3-methyl-5-isopropylhydantoin ( MVH ) as degration product of N-methylcarbamoyl adduct was quantified by UPLC/MS/MS in multiple reaction monitoring ( MRM ) by internal standard method. A good linear relationship was obtained in the MVH concentration range of 0 . 01-1 . 0 μmol/L with the correlation coefficient of 0 . 999 . The recovery of added MVH in the blank sample was 97 . 3% and the relative standard deviation was 1 . 7%. The limit of detection (LOD) was 0. 01 μmol/g. This method was proved to be fast and efficient.

Effect of antenatal taurine supplementation on the taurine levels in brain of fetal rat with intrauterine growth restriction / 中华实用儿科临床杂志

Objective To examine the taurine levels and determine the influence of antenatal taurine on the taurine content in the brains of fetal rats with intrauterine growth restriction (IUGR).Methods Fifteen pregnant rats were randomly divided into 3 groups:normal control group,IUGR group and the IUGR + antenatal taurine supplement group(taurine group) (n =5).IUGR models were induced by low protein diet throughout gestation period.Taurine was added to the diet of the taurine group with a dose of 300 mg/(kg · d) from 12 days after conception until natural delivery.Two fetal rats were randomly selected from each nest and were sacrificed to obtain the brains,and the taurine levels in fetal rat brains were detected by high performance liquid chromatography-mass spectrometry.Results The average weight of fetal rats in the normal control group,the IUGR group and the taurine group were (6.619 ± 0.413) g,(4.509±0.454) g,(5.176 ±0.436) g,there was a significant difference among the 3 groups(F =429.818,P ＜ 0.01).The taurine levels in fetal rat brain in the normal control group,the IUGR group,and the taurine group were (2.399 ±0.134) × 103 μg/g,(1.881 ±0.166) × 103 μg/g and(2.170 ±0.191) × 103 μg/g,there was a significant difference among the 3 groups(F =24.828,P ＜ 0.01).Conclusion Antenatal taurine supplementation can significantly increase the taurine level in fetal rat brain with IUGR.

Artemisia herba alba & Artemisia monosperma: The Discovery of the first potential Egyptian plant sources for the Pharmaceutical Commercial Production of Artemisinin and Some of Its Related Analogues.

Artemisinin has received considerable attention in the last few decades as the current drug of choice for treatment of malaria and a number of other diseases. Because of the development of resistance against other malarial drugs, the demand for artemisinin has rapidly increased during the past decade. However, the supply of artemisinin is troublesome as neither total nor semi-synthesis is economically feasible and the only plant species known to produce artemisinin, Artemisia annua L., contains only low amounts of this compound ranging from (0.01-0.6%) of dry weight. The wish to improve the overall supply of artemisinin at a reduced market price has encouraged interest to hit upon novel plant sources for artemisinin production as alternative to A. annua. In our current study a fingerprint profile method was developed for the detection and quantification of artemisinin and its related analogues in the methanolic extract of Artemisia monosperma and Artemisia herba alba using a high-performance liquid chromatography (HPLC) with diode-array detector (DAD) and ion trap mass spectrometry. Artemisinin, dihydroartemisinin (α and β isomers), artemisitene, dihydroartemisinic aldehyde, dihydroartemisinic acid, dihydroartemisinic alcohol were detected and quantified in the methanolic extract of Artemisia monosperma using LC-MS peak at concentrations of 3.6, 1.9, 0.27, 0.06, 0.08 and 1.95 % of dry plant weight respectively in addition to the detection of arteannuin B and artemisinic acid at a trace levels. While artemisinin, artemisitene, dihydroartemisinic acid, and artemisinic acid were detected and quantified in the methanolic extract of Artemisia herba alba at concentrations of 4.9, 0.35, 0.08 and 0.04 % of dry plant weight respectively . The high unexpected concentration of artemisinin and some of its related analogues detected in this study reported Artemisia herba alba and Artemisia monosperma for the first time as a novel potential plant sources for artemisinin and some of its related analogues that may be helpful for its commercial pharmaceutical production and could lead to the improvement of the overall supply of artemisinin at a reduced market price offering an acceptable price for most patients.especially that these Artemisia species are abundant in distribution in Egyptian desert.

Dual-Sensitive Probe of 2-( Benzoacridin) ethyl-imidazole-1-carboxylate for Determination of Aliphatic Amine with Fluorescence and Online Atmospheric Pressure Chemical Ionization Mass Spectrometry Identification / 分析化学

With comparison of three different methods for the marking of amines compound, an optimal deri vatization method was selected.5-(2-Hydroxyethyl) benzoacridine (HBA) reacts with coupling agent N,N'-carbonyldiimidazole(CDI) to form an activated amide intermediate 2-(benzoacridin) ethyl-imidazole-1-carbox-ylate(BAEIC).BAEIC, which is dual-sensitive probe, reacts preferably with amino compounds at 80 ℃ in the presence of 4-dimethylaminopyridine(DMAP) catalyst in N,N-dimethylformamide(DMF) solvent to give the corresponding sensitively fluorescent derivatives with an excitation maximum at λ_(ex) of 280 nm and an emis sion maximum at λ_(em) of 510 nm.BAEIC-amine derivatives simultaneously exhibited high ionization potential with percent ionization (changing from 5.62% to 58.08% in aqueous acetonitrile and from 2.14% to 56.58% in aqueous methanol.Derivatives were not only sensitive to fluorescence but also to MS ionizable potential.The fluorescence detection limits(5/iV = 3) were 0.12-0.59 μg/L.The online APCI-MS detection limits were 1.9-14 μg/L(S/N=5).