Integrated HPLC fingerprinting and multivariate analysis differentiates between wild and cultivated Hedyotis diffusa Willd

Abstract

Hedyotis diffusa Willd (HDW) is widely used to treat various diseases and as a health supplement. The high demand for wild HDW has resulted in the emergence of numerous cultivated HDW. However, there is a little information about the chemical and pharmacological differences between wild and cultivated HDW. In the present study, 20 wild and cultivated HDW samples were collected from different regions in China. An integrated method of high performance liquid chromatography (HPLC) fingerprinting and multivariate analysis, including similarity analysis (SA), hierarchical cluster analysis (HCA), principal components analysis (PCA), and orthogonal partial least square method-discriminant analysis (OPLS-DA), was developed to characterize the differences in chemical compositions between wild and cultivated HDW. The anti-oxidant activity of wild and cultivated HDW was compared using the 2,20-azinobis (3-ethylbenzothiazoline-6-sulphonicacid) diammonium salt (ABTS), the 2, 2-diphenyl-1-picrylhydrazyl (DPPH), and the superoxide radical scavenging activity (SRS) assays. In total, 23 common peaks from fingerprinting chromatograms were included in the multivariate analysis. SA showed obvious differences in similarity values (0.685 - 0.929). Twenty samples were accurately distinguished between wild and cultivated HDW using OPLS-DA, but not HCA and PCA. High performance liquid chromatography (HPLC) coupled with electrospray ionization-quadrupole-time of flight-mass spectrometry (HPLC-ESI-TOF/MS) identified nine major chemical compounds that discriminated between wild and cultivated HDW. The anti-oxidant activity of wild HDW was significantly higher compared with the cultivated HDW. This study provides a suitable method for germplasm discrimination and quality evaluation of HDW and a chemical and pharmacological method to determine a replacement possibility for cultivated HDW.