Lippia umbellata Cav.: Chemical Composition, Insecticidal, and Antimicrobial Activities

Lippia umbellata, a member of the Verbenaceae family, is traditionally employed in Mexico for the treatment of various ailments, including infections. This research reports the insecticidal and antimicrobial potential of hexane extracts from the leaves (LHE) and flowers (FHE) of this plant. The two extracts contained lupenone and α-amyrin as the mains components; induced 100% mortality in Drosophila melanogaster within 72 h of exposure (median lethal dose: LD₅₀ values of 41.23 and 51.68 µg/mL, respectively). In addition, the extracts impaired larval development to the pupal stage and affected the reproduction of the second generation. Enzymatic assays revealed that LHE and FHE inhibit acetylcholinesterase (AChE) in vitro, whereas in silico analyses demonstrated that callicarpifolic acid interacts with the active site. Furthermore, LHE exhibited antimicrobial activity against multidrug-resistant bacterial and yeast strains. To our knowledge, this is the first report of these biological properties in this species. However, further research is needed to elucidate the underlying mechanisms of action of the antimicrobial and insecticidal activities of the plant.