Effect of In Vitro Micropropagation on the Chemical, Antioxidant, and Biological Characteristics of Senecio nutans Sch. Bip., an Endemic Plant of the Atacama Desert Andean Region.

The species Senecio nutans Sch. Bip., commonly called "chachacoma", is widely used as a medicinal plant by the Andean communities of Northern Chile. Ethanolic extracts of S. nutans and the main compound, 4-hydroxy-3-(3-methyl-2-butenyl) acetophenone, have shown interesting biological activity. However, due to the high-altitude areas where this species is found, access to S. nutans is very limited. Due to the latter, in this work, we carried out micropropagation in vitro and ex vitro adaptation techniques as an alternative for the massive multiplication, conservation, and in vitro production of high-value metabolites from this plant. The micropropagation and ex vitro adaptation techniques were successfully employed, and UHPLC-DAD analysis revealed no significant changes in the phenolic profile, with acetophenone 4 being the most abundant metabolite, whose antioxidant and antibacterial activity was studied. Independently of the applied culture condition, the ethanolic extracts of S. nutans presented high activity against both Gram-positive and Gram-negative bacteria, demonstrating their antimicrobial capacity. This successful initiation of in vitro and ex vitro cultures provides a biotechnological approach for the conservation of S. nutans and ensures a reliable and consistent source of acetophenone 4 as a potential raw material for pharmacological applications.