The ginsenoside profile of ginseng cultivated under mountainous forest

Ginseng cultivated under forest was formally called "Lin-Xia-Shan-Shen" (LXSS) according to Chinese Pharmacopoeia (2010 edition) meaning that the seeds of ginseng were disseminated in mountainous forest and the plants grew naturally without pesticide and fertilizer. The accumulation of ginsenosides in LXSS and profile comparison between garden ginseng and LXSS were studied, thus a chromatographic method to distinguish LXSS from garden ginseng was established. In the study, external standard method and multi-components quantification with one marker based on the peak area recorded on HPLC were applied to determine the contents of components in LXSS. Correlation analysis was used to find the correlations between ginsenoside contents and growing years, between appearances and growing years of LXSS. It was found that most components exhibited a trend of first increasing, and then stablizing before finally declining, with the ratio of protopanaxatriol and protopanaxadiol-type ginsenosides decreasing in LXSS. The total weight and length of LXSS were positively correlated to the growing years. The results provided the scientific bases for the optimal collection time of LXSS. Fingerprints of LXSS and garden ginseng were also set up with ginsenoside Rb(1) as reference peak, and 19 and 13 characteristic peaks were identified, respectively. Analysis of components between ginsenosides Re and Rf showed that ginseng samples from different sources were characterized with peak numbers and ratios in this area. Those of LXSS showed several peaks eluted just before ginsenoside Rf, while those of garden ginseng embodied a relative high peak with retention time at 24.3 min.