不同生长时期西洋参花蕾中皂苷成分及最佳采收期的确定

Distribution of Saponins in Flower Buds of American Ginseng in Different Growth Periods and Determination of the Suitable Harvesting Time

采用新型高分辨三合一轨道阱质谱与超高效液相色谱联用的技术(UHPLC/MSn),对西洋参花蕾中所含皂苷成分进行定性分析,并以相对定量法计算峰面积,对西洋参花蕾不同生长时期以及花蕾不同部位的皂苷种类与含量进行测定。从花蕾的70%乙醇水提取液中共检测到49种皂苷,对其定量分析结果表明,这49种皂苷的总含量随花蕾生长发育呈现下降趋势,其中少数单体皂苷如Rg_(1)、mRg_(1)、Rb_(1),其含量在成熟期到开花期期间有所上升,但仍低于最早期(现蕾期)的含量。皂苷在花蕾不同部位的分布研究结果显示,同一颗花蕾花瓣和花柄中皂苷含量较高。综合考虑折干率、皂苷含量与产量确定西洋参花蕾在现蕾期后约2周,开花期以前采摘较为适宜。

A novel high-resolution method based on orbitrap fusion mass spectrometry coupled with ultra high performance liquid chromatography was used to qualify saponins in the flower buds of American ginseng,while the saponin content at 4 stages during flower development and in different parts of the flower buds were analyzed through relative quantification.A total of 49 saponins were detected from the 70%ethanol extracts of the flower buds.The results of quantification analysis showed that the total amount of these saponins decreases with the progress of flower development.Several single saponins,such as ginsenosides Rg_(1),mRg_(1)and Rb_(1),have a slight increase respectively between the maturing stage and the blossom stage of growth,yet still lower than those in the early stage(emerging stage).For the distribution of saponins in different parts of the flower buds,we found that petals and stalks contain much more saponins.Taking drying rate,saponin content and yield into comprehensive considertaion,we conclude that flower buds of American ginseng are suitable to be picked about two weeks after the budding period and before the harvest period.