Sample preparation of Hedyotis diffusa Willd. for two-dimensional gas chromatography-time of flight mass spectroscopic analysis enhanced chemical profiling

Abstract

Hedyotis diffusa Willd., a herbal remedy for cancer, has a complex chemical profile that is difficult to analyze in detail. Here, we introduce an optimized sample preparation method coupled with two-dimensional gas chromatography-time-of-flight mass spectrometry (GC ​× ​GC-TOF/MS) to enhance the chemical profiling of H. diffusa. By employing dichloromethane extraction for nonpolar compounds, aqueous extraction, and solid-phase extraction fractionation into moderately polar and polar fractions, we extracted and analyzed a comprehensive range of chemicals from H. diffusa. GC ​× ​GC-TOF/MS analysis revealed a rich chemical landscape, identifying 185, 325, and 483 peaks in the dichloromethane extract, solid-phase extraction elution, and unretained fractions, respectively. Library matching against known compounds confirmed 155, 178, and 184 hits with a similarity of 80% or greater. Notably, this method also involves group-type elution of steroids and anthraquinones, facilitating the identification and screening of similar compounds. This comprehensive approach to herbal chemical analysis offers a high-dimensional perspective and greatly advances our understanding of the chemical constituents of H. diffusa.

Keywords

Chemical profiling / Hedyotis diffusa willd / Two-dimensional gas chromatography-time-of-flight mass spectrometry / Sample preparation / Herbal medicine

Ethics approval

Not applicable.

Fundings

Not applicable.

CRediT authorship contribution statement

Duxin Li: Writing - original draft, Investigation, Data curation, Conceptualization. Xinying Du: Writing - original draft, Data curation. Wanru Bai: Writing - original draft, Data curation. Oliver J. Schmitz: Writing - review & editing, Project administration, Methodology, Conceptualization.

Data availability

The data used in this study are available upon request from the corresponding author upon reasonable request.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

Not applicable.

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