In this study, a method of metabolite profiling based on UPLC-QTOF/MS was developed to analyze Platycodon grandiflorum. In the optimal UPLC, various metabolites, including major platycosides, were separated well in 15 min. The metabolite extraction protocols were also optimized by selecting a solvent for use in the study, the ratio of solvent to sample and sonication time. This method was used to profile two different parts of P. grandiflorum, i.e., the roots of P. grandiflorum (PR) and the stems and leaves of P. grandiflorum (PS), in the positive and negative ion modes. As a result, PR and PS showed qualitatively and quantitatively different metabolite profiles. Furthermore, their metabolite compositions differed according to individual plant samples. These results indicate that the UPLC-QTOF/MS-based profiling method is a good tool to analyze various metabolites in P. grandiflorum. This metabolomics approach can also be applied to evaluate the overall quality of P. grandiflorum, as well as to discriminate the cultivars for the medicinal plant industry.
Bupleurum falcatum, which belongs to the family Apiaceae, has long been applied for curative treatments, especially as a liver tonic, in herbal medicine. The chloroplast (cp) genome has been an ideal model to perform the evolutionary and comparative studies because of its highly conserved features and simple structure. The Apiaceae family is taxonomically close to the Araliaceae family and there have been numerous complete chloroplast genome sequences reported in the Araliaceae family, while little is known about the Apiaceae family. In this study, the complete sequence of the B. falcatum chloroplast genome was obtained. The full-length of the cp genome is 155,989 nucleotides with a 37.66% overall guanine-cytosine (GC) content and shows a quadripartite structure composed of three nomenclatural regions: a large single-copy (LSC) region, a small single-copy (SSC) region, and a pair of inverted repeat (IR) regions. The genome occupancy is 85,912-bp, 17,517-bp, and 26,280-bp for LSC, SSC, and IR, respectively. B. falcatum was shown to contain 111 unique genes (78 for protein-coding, 29 for tRNAs, and four for rRNAs, respectively) on its chloroplast genome. Genic comparison found that B. falcatum has no pseudogenes and has two gene losses, accD in the LSC and ycf15 in the IRs. A total of 55 unique tandem repeat sequences were detected in the B. falcatum cp genome. This report is the first to describe the complete chloroplast genome sequence in B. falcatum and will open up further avenues of research to understand the evolutionary panorama and the chloroplast genome conformation in related plant species.