NMR metabolic profiling of biomass and medium extracts of Jasmonate or Pectin treated Cannabis sativa L. cell suspension cultures

Cell cultures of medicinal plants are an alternative and promising source of bioactive compounds for medicinal use and they are also a good model system to investigate metabolic pathways. Metabolomics like other –omics methods can be a tool to uncover regulation system of metabolic pathways in order to modify or improve the production of specific compounds. Cannabis sativa L. is an annual dioecious plant from the family Cannabaceae, containing the pharmacologically active compounds, cannabinoids.

NMR metabolomics was used to study the metabolic profilings of crude biomass and medium extracts in two suspension cultures (“GB“ and „GC“) of C. sativa„Fourway“ initiated from leaves. Aqueous methanol and ethyl acetate solvent systems were used for the cells and medium extractions respectively. High resolution NMR was used to identify and quantify the production of metabolites during a time course of elicited suspension cultures with Jasmonic acid or Pectin. Principal component analysis (PCA) was applied to the ¹H NMR spectra. For the structure elucidation we used 2D NMR (J-resolved, COSY, HSQC and HMBC). PCA results were correlated with growth curves and cell viability of the cell suspension cultures.

Jasmonic acid showed greater effect on the cell metabolism of the C. sativa cell cultures than Pectin. Increased production of aromatic compounds was the main impact provoked by the elicitation, according to the PCA separation. These effects were observed from second week after the elicitor treatment, when the cultures reached stationary growth phase. It was also observed that in the GB culture an 1,4-disubstituted benzene analogue was accumulated inside the cells, while in GC culture this compound was excreted to the medium; suggesting the presence of a transport system for this compound or a different metabolite storage strategy. 2,5-dihydroxybenzoic acid and a cinnamic acid derivative were detected in the medium fraction without any response to elicitation.