ABSTRACT
Objective:To establish the fingerprints of Microctis Folium by ultra high performance liquid chromatography (UPLC); To determine the contents of three flavonoids in the Microctis Folium; To evaluate the quality difference of Microctis Folium from different producing areas. Methods:The fingerprints were performed on Agilent ZORBAX SB C18 column (2.1 mm×150 mm,1.8 μm). The mobile phase was acetonitrile - 0.1 % acetic acid solution with gradient elution at a flow rate of 0.30 ml/min. The column temperature was 30 ℃ and the detection wavelength was 315 nm. The common fingerprint peaks were identified by UPLC-mass spectrometry, and the identification results were confirmed by comparison of reference materials. Waters Cortecs T3 C18 chromatographic column (2.1 mm × 100 mm,1.6 μm) was used for content determination. The mobile phase was methanol-0.1 % formic acid solution with gradient elution at a flow rate of 0.35 ml/min. The column temperature was 30 ℃ and the detection wavelength was 339 nm. The contents of vitexin, isovitexin and narcissoside in 15 batches of Microctis Folium from different habitats were determine. Results:There were 11 common peaks in the fingerprint of Microctis Folium. Identified by mass spectrometry and confirmed by reference substance,10 chemical components were identified, including caffeic acid, p-hydroxycinnamic acid, ferulic acid, vitexin, isovitexin, kaempferol-3-O-rutoside, astragaloside, narcissoside, isorhamnetin-3-O-glucoside and linden glycoside. The similarity between the fingerprints of 15 batches of Microctis Folium and the control fingerprint was greater than 0.95, indicating that the overall similarity of the fingerprints of Microctis Folium from different producing areas was high. The total contents of three active components were 3.23-5.64 mg/g in Yangjiang City, Guangdong, 3.60-5.78 mg/g in Zhanjiang City, Guangdong, 4.68-5.73 mg/g in Yulin City, Guangxi and 3.87-5.21 mg/g in Wuzhishan City, Hainan . There was no significant difference in the content of three active components in different producing areas. Conclusion:The fingerprints and the determination method established in the study are stable and feasible, which can be used for the quality evaluation of Microctis Folium.
ABSTRACT
Objective:To analyze the chemical constituents in Microctis Folium by ultra performance liquid chromatography-quadrupole-time-of-flight high resolution mass spectrometry （UPLC-Q-TOF-MS/MS）. Method:Waters CORTECS UPLC C<sub>18</sub> column （2.1 mm×150 mm， 1.6 μm） was used for chromatographic separation with the mobile phase of methanol （A） -0.1% formic acid solution （B） for gradient elution （0-4 min， 14%-30%A； 4-16 min， 30%-58%A； 16-25 min， 58%-78%A； 25-25.1 min， 78%-98%A； 25.1-29 min， 98%A）， the flow rate was 0.25 mL· min<sup>-1</sup>， the injection volume was 1 μL. The electrospray ionization （ESI） was adopted for determining the chromatographic effluent under positive and negative ion modes， the main chromatographic peaks were assigned and distinguished by Q-TOF， and the scanning range was <italic>m</italic>/<italic>z</italic> 100-1 500. Result:A total of 31 chemical constituents in Microctis Folium were identified by confirmation of reference substances， literature comparison and high resolution mass spectrometry data analysis. The chemical constituent cluster was composed of 28 flavonoids （9 flavone C-glycosides， 10 flavonols and their glycosides， 8 proanthocyanidins， 1 xanthone） and 3 organic acids （caffeic acid， <italic>p</italic>-coumaric acid， ferulic acid）. Conclusion:UPLC-Q-TOF-MS/MS technique provides a simple， rapid and accurate method for the identification of chemical constituents in Microctis Folium. Flavone C-glycosides， flavonol oxyglycosides and proanthocyanidins are the main chemical constituents. The 7 proanthocyanidins are reported for the first time in this herb. In conclusion， the chemical profile of Microctis Folium is characterized and the findings are meaningful for the in-depth quality assessment and material basis clarification of Microctis Folium.
ABSTRACT
Objective:To develop a UPLC method for determining four glycosides in microctis folium.Methods:The UPLC deter-mination was performed on an Agilent SB -C18 (3.0 mm ×50 mm, 1.8 μm) colume with 0.05% acetonitrile -phosphate solution as the mobile phase.The detection wavelength was set at 320 nm.The flow rate was 0.3 ml· min-1.The column temperature was 25℃.Results:Narcissoside, isovitexin, kaempferol-3-rutinoside and isorhamnetin-3-O-glucoside all showed good linearity with the re-covery of 98.89%,99.03%, 97.00%and 97.41%, and RSD of 0.41%, 0.84%,0.44%and 0.80%, respectively (n=9).Con-clusion:The method is convenient with good stability , repeatability and sample recovery rate , which provides basis for the quality eval-uation and control of microctis folium.