Nanoencapsulation of the Aranto (Kalanchoe daigremontiana) aquoethanolic extract by nanospray dryer and its selective effect on breast cancer cell line

The Aranto (Kalanchoe daigremontiana) is a succulent and xerophytic plant that contains glycosides, flavonoids and lipids; these last ones include triterpenoids and bufadienolides that have cytotoxic activity against various cancer cell lines. In this investigation applied to anticancer therapy, it was obtained an aquoethanolic extract from K. daigremontiana, and nanoencapsulated in Poly (D, L-lactide-co-glycolide) (PLGA), by the nanospray drying technique. In vitro experiments showed that the nanocapsules (NC) containing the aquoethanolic extract from K. daigremontiana had a better cytotoxic effect (IC₅₀ 48.53 μg/ml), compared to the non-encapsulated aquoethanolic extract (IC₅₀ 61.29 μg/ml) in the MDA-MB-231 metastatic breast cancer cell line. On the other hand, when comparing the cytotoxic effect in the breast non-cancerous cell line MCF 10A we found no cytotoxic effect of the NC containing the aquoethanolic extract of K. daigremontiana with concentrations of the extract equal or lower than 200 μg/ml, whereas the aquoethanolic extract which was not encapsulated had a positive cytotoxic effect (IC₅₀ 100.2 μg/ml). These results showed an important selectivity of the cytotoxicity of the NC with the aquoethanolic extract to the cancerous cells.