New antibacterial germacrene from Verbesina negrensis.

Several health benefits have been attributed to members of the Verbesina genus, including promotion of urinary and gastrointestinal health. Verbesina species are also reported to exhibit antibacterial, antiparasitic, and antioxidant activities. Although members of the Verbesina genus produce various pharmacologically relevant chemicals as secondary metabolites, including eudesmanes, flavonoids, guanidine alkaloids, acetylenic compounds, and germacrenes, the active compounds required for these benefits remain unknown.