A comprehensive evaluation protocol for sulfur fumigation of ginseng using UPLC-Q-TOF-MS/MS and multivariate statistical analysis

Abstract

Ginseng (Panax ginseng), a tonic and functional food in Asia and among the ten top-selling herbal remedies worldwide, is often sulfur-fumigated (SF) during post-harvest handling. In this study, a practical protocol was developed using ultra-high performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) and multivariate statistical analysis to identify characteristic SF markers, dissect chemical transformation mechanism, and control the quality of SF ginseng. The result showed that sulfur fumigation significantly altered the holistic chemical profile of ginseng by triggering chemical transformation of certain original components, 14 ginsenosides and its metabolites together with 2 potential sulfur-contained ginsenoside sulfates were screened out to be the most characteristic markers for distinguishing non-fumigated (NF) and SF ginseng. Moreover, the transformation mechanism of the sulfates of ginsenoside Rg1, Rh1 and 24(R)-pseudoginsenoside Rt5 was inferred, and which showed that in addition to hydrolysis, esterification and dehydration reaction occurred in the process of sulfur fumigation. This study shows that the comprehensive evaluation protocol-based chemical profiles and discriminated markers can be applied to quality evaluation of NF and SF ginseng and other edible or medical materials.