Alkaloids of Ervatamia pandacaqui / 中国药科大学学报

@#Eleven alkaloids were isolated from the twigs and leaves of Ervatamia pandacaqui using chromatographic methods of silica gel, Sephadex LH-20, ODS, and HPLC.Their structures were elucidated by physical,chemical and spectroscopic methods and determined as voacristine 7-hydroxyindolenine (1),iboxygaine (2), 19S-hydroxyibogamine (3), 3-oxotabersonine (4), perivine (5), pericyclivine (6), rhazinalinol (7), geissoschizol (8), 3, 14-dihydroolivacine (9), vallesamine (10), and conolobine A (11), respectively.All compounds were isolated from this plant for the first time.

Research progress of exosomes in epithelial-mesenchymal transition / 南方医科大学学报

Exosome, a membranous vesicle with biological activity, not only transmits active substances between cells but also transfers information between cells to participate in cell communication. Epithelial-mesenchymal transition (EMT) is a process by which epithelial cells acquire migratory and invasive properties to become mesenchymal stem cells. EMT is essential for the development of a spectrum of diseases. Studies have shown that exosomes have dual effects on EMT to, on the one hand, promote EMT and tumor cell invasion and metastasis and accelerate angiogenesis and tumor growth; on the other hand, exosomes can suppress tumor cell invasion, inhibit fibrosis of the heart, liver and kidney, and improve myocardial infarction by inhibiting EMT. Exosomes modulate EMT-related signaling pathways by carrying EMT-related proteins or miRNA to exert their bi-directional regulatory effects.

Phenols from Vitex negundo / 中成药

AIM To study the phenols from Vitex negundo Linn..METHODS The ethyl acetate fraction of 70％ ethanol extract from V.negundo was isolated and purified by silica,Sephadex LH-20 and ODS column,then the structures of obtained compounds were identified by spectral data.RESULTS Seven compounds were isolated and identified as luteolin-4'-O-β-D-glucopyranoside (1),isoorientin 6-O-caffeate (2),3,4,5-tricaffeoyl quinic acid (3),(+)-pinoresinol-4-O-β-D-glucoside (4),methyl isoferuloyl-7-(3,4-dihydroxyphenyl) lactate (5),benzyl 7-O-β-D-glucoside (6) and oresbiusin A (7).CONCLUSION All the compounds are isolated from this plant for the first time,and compounds 1,3,5-7 are first isolated from genus Vitex.

Rapid Determination of 25 Kinds of Fungicides in Cereals, Fruits and Vegetables by Solid Phase Extraction and Liquid Chromatography Coupled with Quadrupole-Time of Flight Mass Spectrometry / 分析化学

A method for simultaneous determination of 25 kinds of fungicides in cereals, vegetables and fruits using SPE-LC-Q-TOF/MS technique was developed.The samples were extracted with acetonitrile containing 1% (V/V) acetic acid, purified by solid phase extraction (SPE) with a Crabon/NH2 cartridge, eluted with acetonitrile-toluene(3∶1, V/V), separated by a reversed phase C18 column, gradiently eluted with acetonitrile and 0.1% formic acid solution (Containing 5 mmol/L ammonium acetate), determined by LC-Q-TOF/MS, and quantified by external standard method.A data base of the accurate mass numbers and a library which contains 25 kinds of fungicides were established.The automatic retrieval of detection results was carried on according to the characteristics of the compound, such as accurate mass, retention time, isotope peak distribution, isotopic ratios, and so on.Based on the above results, the qualitative identifications of the 25 new fungicides were accomplished without the contrast of standard substances.The results indicated that 25 fungicides showed good linearity in the range of 0.02-200 μg/L, and the limits of detection (LOD) and the limits of quantification (LOQ) were 0.01-5.00 μg/kg and 0.02-20.00 μg/kg, respectively.The linear relative coefficients were greater than 0.995.The recoveries were in the range 71.8%-114.0% and the relative standard deviations (RSD) were ranged from 0.1% to 21.3% (n=3).The method has some advantages such as simplicity, rapidity and high sensitivity, and is suitable for the rapid determination of the common fungicides in cereals, vegetables and fruits.

Development of a QuEChERs Method for Determination of 20 Perfluorinated Compounds in Animal Liver by HPLC_MS/MS / 分析化学

A method for simultaneous determination of 20 Perfluorinated alkyl substances ( PFAS) in animal liver using QuEChERs and HPLC_MS/MS technique was developed. The samples were extracted with 0. 1%hydrochloric acetonitrile and cleaned up with C18 , N_Propylethylendiamine ( PSA ) and graphitized carbon blacks ( GCB ) . The analytes were separated by a reversed phase C18 column and gradiently eluted with a mixed solution of 5 mmol/L ammonium acetate methanol and 5 mmol/L ammonium acetate. The samples were quantified using isotope internal standard and external standard with the matrix matched standard calibration curve method. Good linearity was obtained for all the 20 PFAS at the concentration of 0. 1-10 μg/L with the linear correlation coefficients more than 0. 9995. The limits of detection (LOD) and the limits of quantification ( LOQ) for PFAS were 0. 05-0. 2 μg/kg and 0. 4-0. 5 μg/kg, respectively. The recoveries at three different concentration levels ( 0 . 5 , 2 and 5 μg/kg ) were in the range of 70 . 3% -108 . 1%. The repeatability expressed as relative standard deviations (RSD) was ranged from 2. 1% to 11. 9% (n=6).

Alkaloids from the leaves of Nauclea officinalis / 药学学报

To study chemical constituents of the leaves of Nauclea officinalis, eight alkaloids were isolated from 95% ethanol extract by various chromatographic methods. The structures were elucidated on the basis of spectroscopic data (IR, UV, ESI-MS, 1D and 2D NMR) and identified as naucleactonin C (1), strictosamide (2), vincosamide (3), pumiloside (4), angustoline (5), angustine (6), 18, 19-dihydroangustine (7) and naucleofficine D (8). Compound 1 is a new indole alkaloid. Compounds 6 and 7 were isolated from this plant for the first time.

A new steroidal glycoside from Lygodium japonicum / 中国药科大学学报

To investigate the chemical constituents from the aerial parts of Lygodium japonicum. Methods:Various chromatographic techniques were employed for isolation and purification of the constituents. The structures were elucidated by chemical evidence and spectral methods. Results:A new stigmasterol glycoside,(24R)-stigmastan-3β,5α,6β-triol 3-O-β-D-glucopyranoside (1),together with three known phenolic glycosides:6-O-p-coumaroyl-D-glucopyranose (2),6-O-caffeoyl-D-glucopyranose (3),1-O-(E)-caffeoyl-β-D-gentiobiose (4) were obtained and identified by spectroscopic methods. Conclusion:All compounds were isolated from Lygodiaceae for the first time.

A new phenolic glycoside from fruits of Citrus aurantium / 中草药

Objective To study the bioactive constituents of the immature fruits of Citrus aurantium. Methods Silica gel and Sephadex LH-20 were used to isolate the constituents of this plant. The spectroscopic methods were applied for their structural elucidation. Results Four compounds were isolated from the ethanol extract of the immature fruits of C. aurantium. These compounds were elucidated as 3, 5-dihydroxyphenyl 1-O-(6′-O-trans-feruloyl)-?-D-glucopyranoside (Ⅰ), hesperetin (Ⅱ), 4′, 5, 7, 8-tetra- methoxyflavone (Ⅲ), and limonin (Ⅳ). Conclusion Compound Ⅰ is a new phenolic glycoside.