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  • Author or Editor: L.Q. Li x
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Summary

A reversed-phase high-performance liquid chromatographic method was developed for the first time to simultaneously determine salicin and eight flavonoids in leaves of Salix matsudana, that is salicin, luteolin-7-O-glucoside, myricetin, apigenin-3′-oxyethyl-7-O-glucoside, rutin, quercetin, luteolin, kaempferol and apigenin. The separation of these compounds was achieved on a reversed phase C18 column (250 × 4.6 mm, 5 μm), with linear gradient of methanol in 0.2% phosphoric acid solution with a flow rate of 1.0 mL/min with UV detection at 246 nm. The calibration curves for the determination of all analytes showed good linearity over the investigated ranges (r > 0.999). The % relative standard deviation (% RSD) values were less than 0.34%, and the recoveries were between 95.79% and 99.94%. The values of luteolin-7-O-glucoside, salicin, myricetin, apigenin-3′-oxyethyl-7-O-glucoside, rutin, quercetin, luteolin, kaempferol, and apigenin were 1.0 μg g−1, 20.0 μg g−1, 32.9 μg g−1, 2.0 μg g−1, 29.5 μg g−1, 6.0 μg g−1, 1.0 μg g−1, 3.5 μg g−1, and apigenin was not found in the sample. This developed method can be used for evaluating the quality of different plant materials.

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Summary

The chemical compositions of essential oils extracted by n-hexane extract (HE), petroleum ether extract (PE), dichloromethane extract (DE), and hydrodistillation (HD) from Carthamus tinctorius L. (safflower) were analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 86 compounds from four different extracts were identified, and the contents were 97.65%, 98.05%, 98.93%, and 99.68%, respectively. 6,10,14-Trimethyl-2-pentadecanone, hexadecanoic acid, methyl ester, hexadecanoic acid, 8,11-octadecadienoic acid, methyl ester, and 9,12,15-octadecatrien-1-ol were the major constituents of the extracts. The antidiabete activity was assayed in vitro by against protein tyrosine phosphatase 1B (PTP1B). The results showed that the HE exhibited the best in vitro inhibitory enzyme activity against PTP1B, which holds a good potential for treating diabetes and obesity.

Open access

Traditional Chinese medicine (TCM) has been widely used in many countries for thousands of years and played an indispensable role in the prevention and treatment of diseases, especially the complicated and chronic ones. However, the application of TCM in diseases is still not fully recognized by people around the world, the main reason is that Chinese herb is a very complex mixture containing hundreds of different components. Thus, it is essential to make quality control and evaluation of TCM. A new quality evaluation method, quantitative analysis of multi-components by single marker (QAMS), was developed to the quality control of alkaloids in TCM, a case study on Radix aconiti lateralis, named Fuzi in Chinese. Six alkaloids, including aconitine, hypaconitine, mesaconitine, benzoylaconine, benzoylmesaconine, and benzoylhypaconine, were selected as main components to evaluate the quality of Radix aconiti lateralis. The feasibility and accuracy of QAMS were checked by the external standard method, and various high-performance liquid chromatographic instruments and chromatographic conditions were investigated to verify its applicability. Using aconitine as the internal reference substance and the content of aconitine was calculated according to relative correction factors by high-performance liquid chromatography. The present results showed that there was no significant difference observed between the QAMS method and the external standard method with the relative average deviations less than 3.0%, and QAMS is an effective way to control the quality of herbal medicines and seems to be a convenient and accurate approach to analyze multi-composition when reference substances are unavailable.

Open access

An efficient and sensitive analytical method based on precolumn derivatization and gas chromatography—mass spectrometry—selected ion monitoring (GC—MS—SIM) was proposed and validated for analysis of two cembrenediols (CBDs) which are α-cembrenediol and β-cembrenediol in tobacco samples. CBDs in tobacco samples were extracted by sonication with 50 mL dichloromethane for 10 min before derivatized with 2:3 (v/v) bis(trimethylsilyl)trifluoroacetamide (BSTFA)—pyridine at 20 °C for 100 min. CBDs’ level in tobacco samples was analyzed by GC—MS—SIM and quantified by the internal standard method. The linear range for α-CBD and β-CBD was 13.6–554.6 μg mL−1 and 4.11–162.6 μg mL−1, and the correlation coefficients of both were 0.9998. The limit of detection (LOD) and limit of quantification (LOQ) of α-cembrenediol and β-cembrenediol were 0.40 μg g−1 and 1.34 μg g−1, and 0.27 μg g−1 and 0.90 μg g−1, respectively. Average recoveries of α-CBD and β-CBD were 94.4–99.9% and 91.9–98.2% while the relative standard deviations (RSDs, n = 5) were ranged from 2.67 to 5.6% and 2.04 to 4.22%, respectively. This proposed analytical method has been successfully applied to analyze CBDs in tobacco samples.

Open access

Summary

A reversed-phase chiral liquid chromatographic method had been developed and validated for resolution of the enantiomers of racemic fudosteine. The effects on the separation of the amounts of anhydrous cupric sulfate and l-phenylalanine, the methanol content, mobile phase pH, and temperature were investigated. The method was validated for linearity, repeatability, intermediate precision, sample recovery, solution stability, and limits of detection (LOD). l-Phenylalanine and anhydrous cupric sulfate as chiral ligand-exchange complexes were used for separation, isomer identification, related substance investigation, and analysis of fudosteine enantiomers in fudosteine bulk drugs and fudosteine tablets.

Open access

A method was developed for the preparative separation of two alkaloids from the crude extract of the radix of Rauvolfia verticillata (Lour.) Baill. in a single run. The two-phase solvent system composed of petroleum ether–ethyl acetate–methanol–water (5:5:2:8, v/v), where triethylamine (40 mmol/L) was added to the upper organic phase as the stationary phase and hydrochloric acid (10 mmol/L) was added to the lower aqueous phase as the mobile phase, was selected for this separation by pH-zone-refining counter-current chromatography (PZRCCC). For the preparative separation, the apparatus was rotated at a speed 850 rpm, while the mobile phase was pumped into the column at 2 mL/min. As a result, 112 mg of reserpine and 21 mg of yohimbine were obtained from 3 g of crude extract in a single run. The analysis of the isolated compounds was determined by high-performance liquid chromatography (HPLC) at 230 nm with purities of over 91.0%, and the chemical identification was carried out by the data of electrospray ionization–mass spectrometry (ESI–MS) and nuclear magnetic resonance (NMR) spectroscopy. The technique introduced in this paper is an efficient method for preparative separation of reserpine and yohimbine from devil pepper radix. It will be beneficial to utilize medicinal materials and also useful for the separation, purification, and pharmacological study of Chinese herbal ingredients.

Open access