Partial least squares discriminant analysis (PLS？DA) of？fourier transform infrared spectroscopy (FT？IR) metabolic fingerprinting data of？ginseng enables to？differentiate ginseng cultivars, cultivation age of？cultivated/ex vitro and？in？vitro cultured samples

Abstract

Ginseng (Panax species), are significant medicinal plants, have been utilized worldwide for their nutritional and therapeutic properties throughout history. While traditional cultivated ginseng is typically harvested after 6 years, and harvesting earlier than 6 years possess lower levels of ginsenosides. Recent technological advances have increased the use of in vitro techniques for production of ginseng biomass and ginsenosides via cell and/or adventitious root culture. Here, the metabolic profiles of a range of ginseng samples systems of cultivation ages, cultivars, and culture systems of in vitro-cultured and field cultivated ginseng were examined to determine whether Fourier-transform infrared (FT-IR) spectra combined with multivariate analysis of whole-cell ginseng extracts could be used for high-throughput sample discrimination. In total, 26 ginseng samples belonging to four categories were analyzed by principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). Dendrograms based on hierarchical cluster analysis (HCA) of the ginseng sample spectral patterns showed that cultivation ages and culture systems were readily clustered into two subgroups in a polysaccharide spectrum-dependent manner. The sample group containing in vitro cell and organ samples was segregated into four subgroups in a nucleic acid spectrum-dependent manner. These results indicated that FT-IR spectroscopy combined with multivariate statistical analysis of in vitro and ex vitro ginseng could be used as an alternative method for metabolite discrimination. Consequently, PLD-DA analysis of FT-IR metabolic fingerprinting data could serve as a valuable tool for screening bioactive compounds and exploring metagenomic relationships in ginseng research.