A new tool for linking cultivation conditions with chemical profiles to evaluate Chinese medicinal material germplasm

In recent ten years, the germplasm resources of Chinese medicinal materials (CMMs) have been endangered due to widespread environmental damage and ecosystem. Supplies of many CMMs are decreasing. As wild species and varieties disappear, germplasm is lost. This germplasm could be valuable for improving pharmaceutical efficacy of the plants and for ensuring the plant’s survival as climate changes. Thus, it is necessary to evaluate the germplasm resources of Chinese medicinal materials. The clinical effects of CMMs are generally attributed to bioactive chemicals, which belong to plant secondary metabolites. The superior germplasm resources of a CMM must be responsible for producing the higher amounts and/or special types of bioactive chemicals. In the past twenty years, some studies on the germplasm resources of CMM have been carried out; these studies have focused on the molecular characteristics of CMM germplasm resources. However, the molecular mechanisms do not necessarily relate specific genes with the production of specific secondary metabolites. We propose to take a different approach: focusing on plant lipids. Environmental changes can alter plant lipid profiles, and plant lipids participate in the production of secondary metabolites by regulating signaling pathways. In plant biology, the technique of plant lipidomics has been applied to follow metabolic changes in response to developmental, environmental, and stress-induced physiological influences. Thus, comparing the characteristics of plant lipids in the same species growing in different regions should more clearly elucidate the relationship between environment and bioactive chemicals for evaluating the germplasm resources of CMMs. In this study, we will study the medicinal material Xihuangcao involving Isodon lophanthoides (Buch.-Ham. ex D. Don) H. Hara, I. lophanthoides var. graciliflorus (Benth.) H. Hara and I. serra (Maxim.) Kudô from different growing areas. Firstly, samples from various regions will be collected. Their bioactive chemical profiles will be determined by ultra-high definition accurate mass quadrupole time-of-flight with ultra-high performance liquid chromatography (UHPLC-QTOF-MS). Then a lipidomic approach will be developed to characterize the lipid profiles of the samples by UHPLC-QTOF-MS. Finally, differences in the lipid profiles will be analyzed. The results can reveal the influences of environment on various germplasm resources of Xihuangcao. Moreover, it would be feasible to elucidate the role of plant lipids in the production of bioactive chemicals by comparing the lipid and bioactive chemical profiles. The results will reveal the superior germplasm resources of Xihuangcao, which is helpful for its authentication and the selection of plantation cite. More importantly, the research work will provide a new tool for studying the germplasm resources of other CMMs.