Seasonal Variation and Possible Biosynthetic Pathway of Ginsenosides in Korean Ginseng Panax ginseng Meyer

摘要

Whereas Korean ginseng, Panax ginseng Meyer, is harvested in the fall, the variation ofginsenoside content in field-grown ginseng across seasonal development has never been investigatedin Korea. Thus, ultra-high performance liquid chromatography (UHPLC) analysis of nine majorginsenosides, including ginsenoside Rg1, Re, Rf, Rg2, Rb1, Rc, Rb2, Rd, and Ro, in the roots offive-year-old P. ginseng cultivated in Bongwha, Korea in 2017 was performed. The total ginsenosidecontent changed as many as three times throughout the year, ranging from 1.37 ± 0.02 (dry wt %) inJanuary to 4.26 ± 0.03% in May. Total ginsenoside content in the harvest season was 2.49 ± 0.03%.Seasonal variations of panaxadiol-type ginsenosides (PPD) and panaxatriol-type ginsenosides (PPT)were found to be similar, but more PPD was always measured. However, the seasonal variation ofoleanolic acid-type ginsenoside, Ro, was different from that of PPD and PPT, and the highest Rocontent was observed in May. The ratio of PPD/PPT, as well as other representative ginsenosides,was compared throughout the year. Moreover, the percent composition of certain ginsenosides inboth PPD and PPT types was found to be in a complementary relationship each other, which possiblyreflected the biosynthetic pathway of the related ginsenosides. This finding would not only providescientific support for the production and quality control of the value-added ginseng products, but alsofacilitate the elucidation of the ginsenoside biosynthetic pathway.