Self-assembly nanoparticles of 7α-acetoxy-6β-hydroxyroyleanone isolated from Plectranthus hadiensis

The Plectranthus genus belongs to the Lamiaceae family and consists of around 300 species distributed from Africa to Asia and Australia. Plectranthus spp. has been reported to be rich in diterpenoids, such as different types of royleanones. One of Plectranthus medicinal plant species is P. hadiensis (Forssk.) Schweinf. ex Sprenger, which contains diverse metabolites such as phenolic and diterpenoid compounds. Furthermore, this plant is widely used in an array of traditional and Ayurveda recipes for the treatment of diverse range of ailments like cancer.

Therefore, the aim of this work was to isolate large amounts of the cytotoxic royleanone
7α-acetoxy-6β-hydroxyroyleanone by fractionation of a P. hadiensis acetonic extract through an ultrasound-assisted extraction method. This royleanone was studied by cyclic voltammetry and employed as a starting material for the synthesis of self-assembled squalene nanoparticles. The obtained compound was characterized by spectroscopic methods, mainly NMR techniques. Additionally, the nanoparticles characterization, the ability to release the drug unit and the preliminary evaluation of their biological activity in different cell lines will be also tested in the future.

Acknowledgements: This project was funded by the Fundação para a Ciência e a Tecnologia (FCT, Portugal), through projects UIDP/04567/2020 and UIDB/04567/2020. E.M.D-M gratefully acknowledges had been the recipient of the grant UID/DTP/O4567/2019-CBIOS/BI1 and have, currently, a predoctoral FPU 2019 fellowship from the University of Alcalá de Henares.