Chemical composition, anti-insect and antimicrobial activity of Baccharis darwinii essential oil from Argentina, Patagonia

Essential oils (EO) are interesting alternatives to synthetic agents for crops and health protection. This is the first time the composition, potential anti-insect activities and antifungal properties of the essential oil from Baccharis darwinii collected in Patagonia, Argentina, are reported. It would affect Ceratitis capitata, “Mediterranean Fruit Fly,” and Triatoma infestans, Chagas disease vector, and would work as a source of antifungals to treat microbial infections. The chemical composition of the essential oils obtained by hydro-distillation from the aerial parts was analyzed by GC and GC/MS. Forty components were identified, representing 97.2% of the total oil. The major components with recognized anti-insect and antimicrobial activity were limonene (47.1%), thymol (8.1%) and, 4-terpinelol (6.4%). The in vitro evaluation of the anti-insect properties showed promising insecticidal activity against C. capitata (LD50 19.9–31.0 μg/fly for males and females respectively at 72 h) and repellent activity against T. infestans (average repellence 92%). In addition, the oil exhibited strong antifungal activity against yeast and dermatophytes of clinical relevance, including some fungi such as Candida spp and Trichophyton spp with MIC values between 62.5 and 125 μg/mL.

► The flora from Patagonia Argentina is a potential source of bioactive compounds.
► B. darwinii essential oil were rich in limonene, thymol and 4-terpineol.
► The oil showed good anti-insect properties against T. infestans and C. capitata.
► The essential oil has a high content in the recognized antifungal limonene.