固相萃取-高效液相色谱法测定枣中熊果酸和齐墩果酸

DETERMINATION OF OLEANOLIC ACID AND URSOLIC ACID IN CHINESE JUJUBE BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY WITH SOLID-PHASE EXTRACTION

采用正交设计方法优化枣中熊果酸和齐墩果酸的提取工艺,并建立熊果酸和齐墩果酸的固相萃取-高效液相色谱测定方法。样品经乙醇提取,减压浓缩,C18固相萃取小柱净化后,采用高效液相色谱方法分离,以甲醇-磷酸盐溶液作流动相,等度洗脱,紫外检测器检测。齐墩果酸和熊果酸在0.01～1.0mg/mL浓度范围内与峰面积线性良好,线性相关系数分别为0.9998和0.9999。样品的平均加标回收率为95.1%～98.8%,方法的检出限为1.0～3.7μg/mL(S/N=3),同一样品测定结果的相对标准偏差小于2.0%(n=7)。方法具有简单、快速,灵敏、可靠的特点,适用于枣及枣类产品中熊果酸和齐墩果酸含量的测定。

The method of extraction oleanolic acid and ursolic acid from Chinese jujube was explored using four - level orthogonal array design, and a solid -phase extraction （SPE） - high performance liquid chromatography（ HPLC ） method was developed. The analytes in jujube were extracted with alcohol. The extract concentrated by a rotary evaporator and cleaned up using an SPE - C18 cartridge. Subsequently, the anslytes was separated and quantitatively determined by reversed -phase HPLC with ultraviolet detector. The method had a good linearity in the range of 0.01 - 1.0 mg/mL. The detection limits of oleanolic acid and ursolic acid were 1.0 - 3.7 μg/mL, and spiked recoveries were in the range of 95.1% - 98.8% with the relative standard deviations less than 2.0%. It conluded that the proposed method is rapid, accurate and sensitive, and it can be used to detect oleanolic acid and ursolic acid in jujube.