超高效液相色谱-电雾式检测器测定福建产绞股蓝中绞股蓝皂苷XLVI和LVI北大核心CSCD

该研究利用超高效液相色谱-电雾式检测器(UHPLC-CAD)建立了福建产绞股蓝中绞股蓝皂苷XLVI和LVI含量的测定方法。首先利用超高效液相色谱-四极杆-飞行时间质谱(UHPLC-Q-TOF/MS)结合UHPLC-CAD鉴定了福建产绞股蓝的主要成分,其中绞股蓝皂苷XLVI、LVI以及二者相应的含丙二酰基酸性皂苷为其主成分,因此在含量测定时先进行碱水解预处理将酸性皂苷转化为对应的去丙二酰基中性皂苷,再利用UHPLC-CAD测定碱水解后绞股蓝皂苷XLVI和LVI的含量。将绞股蓝样品粉末在乙醇-水-氨水(50∶46∶4,v/v/v)和料液比1∶150(g∶mL)条件下超声提取30 min,静置24 h后,在Waters ACQUITY UPLC BEH C18色谱柱(100 mm×2.1 mm,1.7μm)上分离,采用0.1%(v/v)甲酸水溶液和乙腈作为流动相进行梯度洗脱,流速0.5 mL/min,柱温40℃,电雾式检测器检测。结果表明,绞股蓝皂苷XLVI和LVI分别在9.94~318.00μg/mL和12.78~409.00μg/mL范围内具有良好的线性关系,相关系数(r)分别为0.9993和0.9995。方法精密度、重复性和24 h稳定性试验的相对标准偏差(RSD)均小于2.0%(n=6),绞股蓝皂苷XLVI与LVI的加标回收率分别在100.2%~107.2%与97.9%~104.2%范围内,RSD值分别为2.4%与2.6%。16批绞股蓝样品含量测定结果显示:绞股蓝皂苷XLVI含量占0.57%~2.57%,绞股蓝皂苷LVI含量占0.66%~2.99%。该方法灵敏度高,重复性好,可用于福建产绞股蓝的质量研究和质量控制。

Determination of gypenoside XLVI and LVI in Gynostemma pentaphyllum from Fujian by ultra-high performance liquid chromatography-charged aerosol detector

Gynostemma pentaphyllum (Thunb.) Makino contains dammarane-type triterpenoid saponins, similar to ginseng, with a host of pharmacological activities. However, its planting resources and chemical composition are quite complex. The chemical constituents of Gynostemma pentaphyllum vary drastically among different origins and varieties. Thus, the corresponding quality control methods also need to be different. Currently, limited information is available about the quality control of Gynostemma pentaphyllum from Fujian. A new method based on ultra-high performance liquid chromatography-charged aerosol detection (UHPLC-CAD) was established for the determination of gypenoside XLVI and LVI in Gynostemma pentaphyllum. The major components of Gynostemma pentaphyllum were characterized using UHPLC-quadrupole time-of-flight-mass spectrometry (UHPLC-Q-TOF/MS) combined with UHPLC-CAD. The results revealed gypenoside XLVI, LVI, and their corresponding malonyl-containing acidic saponins as the main components. However, malonylgypenoside XLVI and LVI can easily remove their malonyl group and convert to gypenoside XLVI and LVI during the application of Gynostemma pentaphyllum. In this study, the samples were pretreated using alkali hydrolysis to transform the acid saponins completely, and the final contents of gypenoside XLVI and LVI were determined via UHPLC-CAD.