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- Author or Editor: Y. G. Shi x
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Summary
A new method using ultra-performance liquid chromatography (UPLC) in combination with tandem mass spectrometry and a multiple reaction monitoring mode (UPLC-MS/MS-MRM) was developed for simultaneous quantitative determination of anthraquinone derivatives in Radix et Rhizoma Rhei-based medicines. A multi-mode electrospray/chemical ionization (ESCI) and negative ion mode with [M-H]− and its fragments under collision-activated conditions were employed in MS/MS-MRM. The quantitative method was validated and applied to simultaneous determination of anthraquinone derivatives in 21 Radix et Rhizoma Rhei-based medicines. The limits of quantification were in the range of 3.90–9.09 ng mL−1. Average recoveries were between 95.5% and 99.8% with relative standard deviations from 1.8% to 5.3%.
Summary
A high-performance liquid chromatographic (HPLC) method coupled with photodiode array (PDA) detection has been developed and validated for simultaneous analysis of six active components (syringin, hyperoside, baicalin, quercetin, baicalein, and farrerol) of the Chinese medicinal preparation Qin-Bao-Hong antitussive tablet. The optimum conditions for separation were achieved on a 3.9 mm × 150 mm i.d., 5-μm particle, C18 column with a linear mobile phase gradient prepared from acetonitrile and 1% acetic acid at a flow rate of 1.0 mL min−1. Because of the different UV characteristics of these compounds, four detection wavelengths were used for the quantitative analysis (265 nm for syringin, 256 nm for hyperoside and quercetin, 277 nm for baicalin and baicalein, and 296 nm for farrerol). For all the analytes a good linear regression relationship (r > 0.999) was obtained between peak area and concentration over a relatively wide range. The method was validated for repeatability, precision, stability, accuracy, selectivity, and robustness. The validated method was successfully applied to simultaneous analysis of these active components in Qin-Bao-Hong antitussive tablet from different production batches.
Summary
A novel liquid-phase microextraction (LPME) technique, based on a hollow fiber (HF), in conjunction with high-performance liquid chromatography, has been developed for analysis of melamine in milk products. Melamine was extracted directly from milk products by use of a hollow-fiber membrane filled with organic solvent. HFLPME conditions, for example pH, extraction solvent, temperature, stirring rate, and extraction time were optimized. The best extraction efficiency of melamine was achieved under the conditions: pH 9.5, 35 μL n-octanol as extraction solvent, temperature 55°C, stirring rate 300 rpm, and extraction time 30 min. The HF-LPME technique resulted in a preconcentration ratio of 29-fold. Baseline chromatographic separation of melamine was achieved on a C18 column with 96:4 (v/v) 0.02 mol L−1 ammonium sulfate-methanol as isocratic mobile phase. The linearity of the method ranged from 1.0 to 100.0 μg mL−1, correlation coefficient 0.9994. The limit of detection by use of HF-LPME was 0.021 μg mL−1 at a signal-to-noise ratio of 3. The optimized HF-LPME technique was successfully applied to the analysis of melamine in milk products collected from different commodity manufacturing units.
Summary
A simple and rapid method, using online ultraperformance liquid chromatography with photodiode array detection and electrospray ionization mass spectrometry (UPLC-PDA-eλ-ESI-MS/MS), was developed for the in-depth analysis of 50 batches Radix et Rhizoma Rhei. The analysis was performed on a UPLC BEH C18 column using a gradient elution system. Baseline separation could be achieved in less than 7.5 min. At the same time, on the basis of the 50 batches of samples collected from representative cultivated regions, a novel chromatographic fingerprint was devised by UPLC-PDA, in which 27 common peaks were detected and identified by the developed UPLC-MS/MS method step by step according to fragmentation mechanisms, MS/MS data, standards, and relevant literature. Many active components gave prominent [M - H]− ions in the ESI mass spectra. These components include anthraquinones, sennosides, stilbenes, glucose gallates, naphthalenes, and catechins. Furthermore, based on the information of these Radix et Rhizoma Rhei components, and further combined with discriminant analysis, a novel discriminant analysis equation (DAE) was established for the quality control of Radix et Rhizoma Rhei for the first time.
Senescence in a wheat (Triticum aestivum L.) leaf is a programmed degeneration process leading to death. During this process, green leaf area duration (GLAD) and green leaf number of main stem (GLNMS) are gradually reduced. In this study, the two traits of Hanxuan10/Lumai14 DH population at different development stages after anthesis were evaluated under rainfed and irrigated conditions, and QTLs were detected. GLAD and GLNMS of two parents and DH population under rainfed condition were less than those under irrigated condition, and close correlations (P < 0 05) were found between GLAD and GLNMS after 25 DAA under both water conditions. GLAD and GLNMS were co-controlled by major and minor genes. QTLs for GLAD were stably expressed at different development stages after anthesis under both water conditions, such as QGlad22-1B-1, QGlad25-1B-1, QGlad28-1B-2 detected under irrigated condition and QGlad25-1B-3, QGlad28-1B-4 mapped under rainfed condition were located at a 20.7 cM marker interval of Xgwm273-EST122 on 1B chromosome. But QTLs for GLNMS were inducibly and specifically expressed at specific developmental stages after anthesis under both water conditions. The findings provide dynamic genetic information related to wheat senescence.
High-performance liquid chromatography-mass spectrometry (HPLC-MS) method coupled with radical reaction for screening active ingredients from perennial fujimoto bean whole herb was established. The active ingredients, present in perennial fujimoto bean whole herb, possess scavenging effects towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, superoxide, peroxy radical, and hydroxyl radical. The radical scavenging abilities of these active ingredients were evaluated based on the relative peak areas in the HPLC chromatogram. The results indicate that potent antioxidants are present in the anhydrous methanol extract of perennial fujimoto bean whole herb. Based on HPLC-MS analysis, it was found that the scavenging ability can be mostly attributed to the presence of three compounds: cyanidin-3-o-β-d-glucopyranoside, troxerutin, and rutin. The structures were identified based on the MS and nuclear magnetic resonance (NMR) data. Free radical scavenging activity decreased in the following order: troxerutin > rutin > cyanidin-3-o-β-d-glucopyranoside.
Male sterile mutants play an important role in the utilisation of crop heterosis. Male sterile plants were found in S5 generations of maize hybrid ZH2, through continuous sib-mating by using the fertile plants in the same population, we obtained a male sterile sibling population K932MS including sterile plants K932S and a fertile plant K932F. The objective of this study was to clarify the genetic characterisation and abortion characteristics by nucleus and cytoplasm effect analyses, cytoplasm grouping, and cytological observation. The results showed that no difference was found between K932S and K932F in the vegetative growth stage, but K932S had no emerging anther or pollen grains. The segregation ratio of fertile plants to sterile plants was 1:1 in the sibling progenies, while it was 3:1 in self-crossing progenies of K932F. The sterility of K932S could be restored among reciprocal progenies when seven normal inbred lines were used as females respectively. The fertility expression of K932S crossed with 30 testers would be changed in different test-crosses and some backcross progenies. The C-type restorer Zifeng-1 (Rf4Rf4) was able to restore the fertility of K932S, and the specific PCR amplification bands of K932MS were consistent with CMSCMo17. The anther of K932S began abortion at dyad with its tapetum expanded radically and vacuolated: this induced abnormality in the shapes of both dyads and tetrads. The microspore could not develop normally, and then it collapsed and gradually disappeared. Hence, K932MS is a C-type cytoplasmic male sterile mutant with a pollen-free, stable inheritance: it has potential application value for further research.
Summary
Baihe Zhimu Tang (BZT) is a widely used traditional Chinese medicinal formula for the treatment of various diseases; however, its active components have remained unknown. In this study, high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) methods were developed for the analysis of metabolic components of BZT. The HPLC experiments used a reversed-phase Shim-Pack VP-ODS C18 column with the column temperature at 35°C and a mobile phase system consisting of aqueous formic acid (0.05%, υ/υ) and acetonitrile using a gradient elution at the flow rate of 0.2 mL/min−1. The ESI-MS was operated with a single-quadrupole mass spectrometer in both negative and positive ion modes. After oral administration of extraction of BZT, the rat's plasma, urine, and feces were also analyzed; 37 metabolic components including 23 original components and 14 transformative components of BZT were detected. The analysis of metabolic components in BZT by HPLC-ESI-MS methods could be a useful means of identifying the multi-components of BZT and understanding their possible metabolic mechanism of action in the body. The results also narrow the range of active compounds to be found in BZT, and pave the way for further pharmacology and active mechanism research.
