Carlina oxide--a natural polyacetylene from Carlina acaulis (Asteraceae) with potent antitrypanosomal and antimicrobial properties.

Carlina acaulis (Asteraceae) has a long history of medicinal use in Europe due to its antimicrobial properties. The strong activity of Carlina oxide, themain compound of the essential oil of C. acaulis against two MRSA strains, Streptococcus pyogenes, Pseudomonas aeruginosa, Candida albicans, and C. glabrata was confirmed. A strong and selective activity against Trypanosoma brucei brucei with an IC₅₀ of 1.0 μg/mL and a SI of 446 compared to human HeLa cells was recorded. The selective toxicity of Carlina oxide makes it a promising lead compound for the development of drugs to treat African trypanosomiasis and multiresistant gram-positive bacteria.