目的:采用微波萃取-HPLC法测定木兰脂素的含量,并考察4个不同产地辛夷药材中木兰脂素的含量差异。方法:采用微波萃取法,以75%乙醇为溶剂,在76℃恒温800 s萃取辛夷药材中的木兰脂素。Shim-Pack VP-ODS柱(150 mm×4.6 mm,5μm),流动相:乙腈-水(40∶60),流速:0.8 ml/min;柱温:室温,检测波长:238 nm,采用HPLC法测定木兰脂素的含量。结果:以峰面积(A)对浓度(c)作线性回归,回归方程为A=2.922 7×104c-3 617.4(r=0.999 9),在5.6~240.8μg/ml浓度范围内,木兰脂素的峰面积与浓度呈良好线性关系。该法的精密度、重现性和稳定性良好,低、中、高浓度(104.87、127.42和172.51μg/ml)的加样回收率分别为(100.39±1.58)%(、103.82±4.04)%和(103.74±0.13)%(n=3)。采用该法测得河南、河北、湖南、湖北4地所产的辛夷药材中木兰脂素含量分别为(6.59±0.39)%(、3.44±0.48)%、(2.73±0.28)%和(4.18±0.25)%(n=3)。其中河南产辛夷药材中木兰脂素含量最高。结论:本方法简便、准确、稳定、重复性好,可作为辛夷药材及相关制剂质量控制的定量方法。
Objective: To establish a microwave-assisted extraction and HPLC method for determinination of the content of magnolin in Flos Magnoliae from four different origins.Methods: The magnolin in Flos Magnoliae herbs was extracted by 75% ethanol in microwave for 800 s at the temperature of 76 ℃.HPLC was performed on a Shim-Pack VP-ODS column(150 mm×4.6 mm,5 μm) with mixture of acetonitrile and water(40∶60) as mobile phase.The flow rate was 0.8 ml/min.The column temperature was room temperature.The detection wavelength was 238 nm.Results:The regression equation was A=2.922 7×104 c-3 617.4(r=0.999 9),where A was the peak areas and c was the concentration of magnolin.The concentrations of magnolin in the range of 5.6-240.8 μg/ml were in good linearity with chromatographic peak areas.The precision,reproducibility and stability were all good.The average recovery rates of low,middle and high concentrations(104.87,127.42,172.51 μg/ml) of magnolin were(100.39±1.58)%,(103.82±4.04)% and(103.74±0.13)%(n=3),respectively.This method was used to determine the contents of magnolin in Flos Magnoliae from four different origions: He'nan,Hebei,Hunan and Hubei provinces and the contents were(6.59±0.39)%,(3.44±0.48)%,(2.73±0.28)% and(4.18±0.25)%(n=3),respectively.Flos Magnoliae herbs from He'nan province was found to have the highest content of magnolin.Conclusion: The method is simple,accurate,stable and can be used as a quantitative method for quality control of Flos Magnoliae herbs and its preparations.