A new kind of microwave-assisted circumrotation reflux extraction device was constructed and used to study the extraction technology of gallic acid from phyllanthus urmaria L.The extraction principle of the device was same as that of microwave-assisted solvent extraction but using circumrotation techniques as auxiliary stirrer to accelerate the process.Capillary electrophoresis was used to determinate gallic acid in phyllanthus urmaria L extracts in order to evaluate the extraction efficiency of the method.It was found that the most important factors influencing extraction gallic acid were solvent kind and microwave power.The optimum extraction conditions were as follows:water using as solvent,solid-liquid ratio 1∶30(g:mL),microwave power low rail and irradiate time 4 minute.Under the optimum extraction conditions,five experiments were carried out and the average extraction rate of gallic acid in phyllanthus urmaria L was 4.32 mg/g,relative standard deviations(R.S.D.) was 2.2%.Compared with other extraction methods e.g.reflux extraction and microwave-assisted extraction,better extraction efficiency was observed for the microwave-assisted circumrotation reflux extraction.
To establish an HPLC method for separation and determination of stigmasterol,β-sitosterol and lupeol in phyllanthus urinaria L by HPLC.A Eclipse Zorbax XDB-C18 column(4.6 mm×150 mm i.d.,5 μm) was used for chromatographic separation under the conditions with methanol as the mobile phase at flow rate of 0.7 mL/min.The detection wavelength was 210 nm.The results indicated that stigmasterol,β-sitosterol and lupeol could be baseline separated.The linear range of stigmasterol,β-sitosterol and lupeol were 0.4mg/mL～8.8 mg/mL(R2 were 0.9975),0.5～10.0 mg/mL(R2 = 0.9978) and 0.5mg/mL～10.0 mg/mL(R2 = 0.9981),respectively.The mean recoveries of stigmasterol,β-sitosterol and lupeol were 94.4%～95.1%,91.2%～97.9% and 92.4%～104.6 %,respectively.RSD was less than 5%.The method has been applied to monitor the extraction of stigmasterol,β-sitosterol and lupeol in phyllanthus urinaria L by super-critical fluid extraction with satisfactory.
