Rapid discrimination between red and white ginseng based on unique mass-spectrometric features

Red ginseng (RG) and white ginseng (WG), two processed products of Panax ginseng C. A. Meyer, are in high demand due to their unique features. In this study, some of these unique features were identified and confirmed as biomarkers of RG by using ultra-high-performance liquid chromatography-mass spectrometry, data mining, support vector machine, and artificial neural network. Principal component analysis showed clear separation between the RG and WG extracts, indicating the presence of potential discriminators. In addition, 20 features that are dominant in RG were found by data mining. Samples of Panax quinquefolium (PQ) and Panax notoginseng (PN), close relatives of Panax ginseng C.A.Meyer, were investigated and it was found that 17 features which were absent in PQ and PN samples, were present in RG and WG. Five of these markers were identified as nitrogen-containing compounds that have not been previously reported. Finally, we found that RG can be identified among different ginseng medicinal herbs including RG, WG, PQ, and PN samples, by loading four feature markers corresponding to nitrogen-containing compounds into a discriminating model, based on a support vector machine or an artificial neural network. Thus, this study provides an efficient tool to identify RG during pharmacological research.