Callus from Pyrostegia venusta (Ker Gawl.) Miers: a source of phenylethanoid glycosides with vasorelaxant activities Academic Article in Scopus uri icon

abstract

  • © 2019, Springer Nature B.V.Abstract: Pyrostegia venusta (Ker Gawl.) Miers is a plant used for the treatment of respiratory diseases, diarrhea, vitiligo, jaundice and to attenuate vomiting. However, the levels of the active principles exhibit great variation because of the type of soil, tissue, age and environmental conditions. An alternative to obtain a constant production of secondary metabolites is the plant tissue culture technology. In this work, callus from Pyrostegia venusta were exposed to 12.5 g L¿1 polyethylene glycol, 50 g L¿1 sucrose, or were irradiated with UV light to enhance the content of phenolic acids, flavonoids, and antioxidant activity. The biomass was doubled in the control and callus treated with PEG (240 mg dry weight, DW), and triplicated in the medium with 50 g L¿1 sucrose (310 mg DW) in relation to the inoculum at day 21. The highest levels of phenolic acids and flavonoids were obtained in irradiated callus. Phenylethanoid glycosides, as verbascoside, isoverbascoside and leucosceptoside A were identified. The metabolites present in callus presented vasorelaxant activity (65 to 100%). The vasodilation was inhibited between 80 and 90%, in the presence of NG-nitro-l-arginine methyl ester, indomethacin or tetraethylammonium chloride but was not affected by atropine. Data suggest that vasorelaxation was mediated by nitric oxide, derivatives of arachidonic acid, and efflux potassium channels, and independent of muscarinic receptors. This is the first report that identified the metabolites present in P. venusta compact callus and described its vasorelaxant properties. Key message: It was possible to enhance the metabolites production in Pyrostegia venusta callus. The compounds identified corresponded mainly to phenylethanoid glucosides, which exhibited important vasorelaxant activity in isolated rat aorta rings.

publication date

  • October 1, 2019