Essential Oil of Azorella cryptantha Collected in Two Different Locations from San Juan Province, Argentina: Chemical Variability and Anti-Insect and Antimicrobial Activities

Abstract

Essential oils of two populations of Azorella cryptantha (Clos) Reiche, a native species from San Juan province, were obtained by hydrodistillation in a Clevenger-type apparatus and characterized by GC/FID and GC/MS. The compounds identified were 92.3% and 88.7% for A. cryptantha from Bauchaceta and A. cryptantha from Agua Negra respectively. The essential oil composition was similar for both populations with differences in the main components, and in the identity of minor components. The main components of A. cryptantha-BAU essential oil were sabinene (4), betha pinene (5) and delta-cadinol (38) while α-thujene (1), alpha pinene (2), bethe pinene (5) and, delta cadinene (29) were the main monoterpene hydrocarbons in A. cryptantha-AN essential oil wih the addition of 3.0% of oxygenated monoterpenes. Repellent activity on T. infestans nymphs was 100% and 92% for A. cryptantha-AN and A. cryptantha-BAU essential oils respectively. Regarding the toxic effects on C. capitata, the oils were very active with LD50 values of less than 11 µg/fly. Microsporum gypseum, Trichophyton rubrum and T. mentagrophytes and bacteria LM1-E. coli, LM2-E. coli and PI-Yersinia enterocolitica were more sensitive toward the species collected in Agua Negra (MIC equal 125μg/ml). This is the first report on the anti-insect and antimicrobial properties of A. cryptantha essential oil and its composition.