Studies on lignan constituents from Schisandra chinensis (Turcz.) Baill. fruits using high-performance liquid chromatography/electrospray ionization multiple-stage tandem mass spectrometry

A reversed-phase high-performance liquid chromatography-diode array detector-electrospray ionization multiple-stage tandem mass spectrometry (RP-HPLC-DAD-ESI-MS(n)) method has been developed for the detection and analysis of lignan constituents in the methanol extract from the fruits of Schisandra chinensis (Turcz.) Baill. RP-HPLC-DAD-ESI-MS(n) and electrospray ionization Fourier transform ion cyclotron resonance multiple-stage tandem mass spectrometry (ESI-FT-ICR-MS(n)) have been applied to investigate the characteristic product ions of four lignan reference compounds. Then, the logical fragmentation pathways of the lignans have been proposed. By comparing the retention time (t(R)) of HPLC, the ESI-MS(n) data and the structures of analyzed compounds with the data of reference compounds and in the literature, 11 peaks in HPLC have been unambiguously identified and another 5 peaks have been tentatively identified or deduced. Also, in the present paper, the extracted ion chromatograms (EIC) have been used to analyze the lignan isomers. The experimental results demonstrate that RP-HPLC-DAD-ESI-MS(n) is a specific and useful method for the identification of the lignan constituents and their isomers.     

柱前衍生超高效液相色谱-串联四极杆质谱法测定仙草多糖组成及其含量

建立了测定仙草多糖组成及其含量的超高效液相色谱-串联四极杆质谱分析方法。仙草样品在碱性条件下用沸水提取,提取液经固相萃取小柱净化后加三氟乙酸在110℃水解,然后采用1-苯基-3-甲基-5-吡唑啉酮(PMP)衍生。以Waters ACQUITY UPLC BEH C18(2.1 mm i.d.×50 mm,1.7μm)为分析柱,乙腈和缓冲盐溶液(0.5 mmol/L乙酸铵-0.05%乙酸)为流动相进行梯度洗脱分离,流速0.5 mL/min,电喷雾正离子多反应监测模式检测,内标法定量。结果显示8种单糖在1～100μmol/L浓度范围内呈良好的线性关系,相关系数r2均大于0.96,方法的回收率为84%～112%,相对标准偏差(RSD)不高于4.7%。仙草多糖由甘露糖、鼠李糖、核糖、葡萄糖醛酸、半乳糖醛酸、葡萄糖、半乳糖和木糖8种单糖组成,其摩尔百分比为7.4%、5.7%、4.2%、0.9%、28.4%、26.5%、16.4%和10.6%。该法简单、快速、灵敏高、重现性好,可用于仙草多糖的单糖组成分析和含量测定。     

威灵仙及其伪品的FTIR法直接鉴定

采用傅里叶变换红外光谱（FTIR）法，借助OMNI采样器直接测定了中药材威灵仙及其伪品华东菝葜、山木通和毛柱铁线莲的红外光谱，结果发现正伪品的红餐光谱差别较大。因此FTIR法可以直接、快速、准确地对威灵仙与其伪品华东菝葜、山木通和毛柱铁线莲进行区别鉴定。     

广寄生及其不同寄主黄酮总量和微量元素含量的研究

用紫外分光光度法测定广西玉林产5种广寄生及其不同寄主的黄酮总量;原子吸收分光光度法测定广寄生和寄主的Fe、Mg、Zn、Ca、Mn、Cu、Na、K8种微量元素的含量。结果表明:寄主不同,广寄生黄酮总量和微量元素含量存在差异;广寄生的黄酮总量比寄主高,广寄生的K、Mg元素含量比寄主高。     

The Antioxidant and Hypolipidemic Effects of Mesona Chinensis Benth Extracts

In this study, the antioxidant and hypolipidemic effects of Mesona Chinensis Benth (MCB) extracts were evaluated. Seven fractions (F0, F10, F20, F30, F40, F50 and MTF) were obtained from the MCB ethanol extracts. Compared to the commercial antioxidants (vitamin C), MTF and F30 exhibited higher antioxidant activities in the antiradical activity test and the FRAP assay. The half-inhibition concentration (IC50) for MTF and F30 were 5.323 µg/mL and 5.278 µg/mL, respectively. MTF at 200 µg/mL significantly decreased the accumulation of TG in oleic acid (OA)-induced HepG2 cells and reversed the inhibitory effect of Compound C on AMPK (MTF and F30 significantly increased the glucose utilization of insulin-induced HepG2 cells). In addition, the components of MTF were identified by HPLC-MS, which were caffeic acid, quercetin 3-O-galactoside, isoquercetin, astragalin, rosmarinic acid, aromadendrin-3-O-rutinoside, rosmarinic acid-3-O-glucoside and kaempferol-7-O-glucoside. Through statistical correlations by Simca P software, it was found that the main antioxidant and hypolipidemic components of MCB might be caffeic acid, kaempferol-7-O-glucoside, rosmarinic acid-3-O-glucoside and aromadendrin-3-O-rutinoside, which may play important roles in the AMPK pathway. MTF and F30 in MCB could be potential health products for the treatment of hyperlipidemia.     

A rapid ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometric method for the qualitative and quantitative analysis of the constituents of the flower of Trollius ledibouri Reichb

A rapid ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometric (UPLC–ESI-MS/MS) method was developed for the qualitative and quantitative determination of the constituents of the flower of Trollius ledibouri Reichb. The analysis was performed on an AcQuity UPLC™ BEH C₁₈ column using gradient elution with a mobile phase of 0.1% acetic acid and acetonitrile over 20 min. A tandem quadrupole spectrometer operating in either full scan mode or in MS/MS mode for multiple reaction monitoring (MRM) was used for the qualitative and quantitative analysis of the constituents, respectively. According to the mass spectrometric fragmentation mechanism and UPLC–ESI-MS/MS data, the chemical structures of 15 constituents of the flower of T. ledibouri Reichb. were identified on-line without time-consuming isolation and four of them, 2″-O-β-l-galactopyranosylorientin, 2″-O-β-arabinopyranosylorientin, orientin and vitexin, were quantified. The limits of quantification of these four flavonoids were 540, 321, 515 and 220 μg g⁻¹ plant material, respectively. Four commercial samples from different sources were analyzed. The UPLC–ESI-MS/MS method for analyzing the constituents can be used to evaluate the quality of the flower of T. ledibouri Reichb.     

氢化物发生-原子荧光法测定中药葶苈子和黄连中的铅

采用HNO2-H2O2体系和高压釜消解中药样品，以AFS-2202a型双道原子荧光分光光度计和断续流动的氢化物发生法，测定了中药葶苈子和黄连中的铅。优化了光电管负高压，灯电流，屏蔽气和载气流量等实验条件。铅的检出限为0．08μg／L，相对标准偏差为0．34％。对实际样品的测定，结果令人满意。     

Pharmacokinetic study of three active flavonoid glycosides in rat after intravenous administration of Trollius ledebourii extract by liquid chromatography

A selective and sensitive reversed-phase high-performance liquid chromatography method was developed and validated for the simultaneous determination of orientin-2'-O-beta-L-galactopyranosyl (OGA), orientin and vitexin in rat plasma. Blood samples were collected via the fossa orbitalis vein at time intervals after intravenous administration and the concentrations of the three ingredients in plasma were analyzed by HPLC after the plasma protein had been precipitated directly with methanol. OGA, orientin and vitexin were successfully separated using a C18 column with gradient elution composed of acetonitrile and 0.1% acetic acid and were detected at the detection wavelength of 348 nm. Calibration curves of OGA, orientin and vitexin were generated over the range 0.315-161, 0.326-167 and 0.215-110 microg/mL, respectively. The intra- and inter-day precisions (relative standard deviation) for the analysis of the three analytes were between 1.68 and 8.43% with accuracies (relative error) below 8.55%. The mean extraction recoveries were between 70.35 and 86.42%. The developed method was suitable for simultaneous determination of these three active flavonoid glycosides in rat plasma and was successfully applied to investigate the pharmacokinetics of glycosides from Trollius ledebourii in rats.     

Selective and sensitive determination of protoberberines by capillary electrophoresis coupled with molecularly imprinted microextraction

In this work, we developed a novel molecularly imprinted solid‐phase microextraction with capillary electrophoresis method for the selective extraction and determination of protoberberines in complicated samples. The imprinted monolith was prepared in a micropipette tip‐based device by using acrylamide as the functional monomer, ethyleneglyoldimethacrylate as the cross‐linker and dimethylsulfoxide as the porogen, and exhibited an imprinting factor of 2.41 to berberine, 2.36 to palmatine and 2.38 to jatrorrhizine. Good capillary electrophoresis separation was achieved by using 20 mM phosphate buffer at pH 7 as running buffer with the addition of organic modifier of 10% methanol. Parameters such as sample pH value, sample flow rate and sample volume were investigated for imprinted monolith‐based solid‐phase microextraction. An imprinted solid‐phase microextraction with capillary electrophoresis method was developed, the method showed a wide linear range (0.3–50 μg/mL), good linearity (R² ≥ 0.9947) and good reproducibility (relative standard deviations ≤ 0.73%), the limit of detection was as low as 0.1 μg/mL, which was lower than some reported methods based on capillary electrophoresis for protoberberines. The method has been applied for determination of three common protoberberines in Cortex Phellodendri Chinensis, by using a molecularly imprinted monolith as the selective sorbent, most of the matrices in the Cortex Phellodendri Chinensis sample were removed and three protoberberines were selectively enriched and well determined.