Phytochemical and pharmacological screening of Cyperaceae species and isolation of components of Carex praecox

Cyperaceae is a cosmopolitan plant family with approx. 5000 species worldwide. The main constituents of sedges are phenolic compounds (flavonoids, phenolic acids, phenylpropanoids and stilbenoids) [1]. The aim of our work was the pharmacological screening of 26 Cyperaceae species native to Hungary. Based on the results of the antibacterial investigation, Carex praecox Schreb. was chosen to isolate its biologically active constituents.

The dried plant samples of Cyperaceae species were extracted with methanol. The extracts were evaporated, then solved in 50% methanol and subjected to solvent–solvent partition with hexane, chloroform and ethyl acetate. All extracts were tested for their antibacterial effects by disc diffusion method against 8 bacterial strains. Dried aerial parts of C. praecox were extracted and separated with the same methods as in case of the antimicrobial screening study. Then the chloroformic extract was purified by various chromatographic methods, including VLC, MPLC, preparative TLC and HPLC. The structures of the isolated compounds were determined by a combination of NMR and MS measurements, and by comparing the data with literature values. In case of the antibacterial screening study, the ethyl acetate extracts proved to be the most active ones (inhibitory zones 15–20 mm). Among the tested sedges, C. praecox showed the highest antibacterial effect. As a result of the preparative work, to date 14 compounds, among them two novel and two known flavonoids, two novel and two known lignans, vanillin, benzaldehyde, p-cresol, dehydrovomifoliol and its derivative, and a chromene derivative were identified for the first time from the plant.

Publication History

Article published online:
13 December 2021

• References

• 1 Dávid CZ, Hohmann J, Vasas A. Molecules 2021; 26: 2794