Pteronia incana (Burm.) DC - Asteraceae - blue bush
Invasive shrub of South Africa.
„Pteronia incana produces a yellowish oil with a strong fragrance. Interest in this oil has been primarily due to its unique odour properties which make it suitable for use as a fragrance… Pteronia incana oil had a higher content of p-cymene as well as limonene + 1,8 cineole, and lower content of myrcene than that reported by Bruns & Meiertoberens (1987). Moreover, the oil contained o-cymene, which had not been reported… Pteronia incana oil also displayed a fairly broad spectrum of antibacterial activity, particularly at higher concentrations. However, it was less efficient than A. afra and R. officinalis oils. Enterobacter cloacae and Staph. aureus showed the highest sensitivity to P. incana oil.“
[Comparative evaluation of the antimicrobial activities of essential oils of Artemisia afra, Pteronia incana and Rosmarinus officinalis on selected bacteria and yeast strains. Mangena, T., Muyima, N. Y. O., Letters in applied microbiology, Vol.28(4), 1999, 291-296] http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2672.1999.00525.x/ful
„The essential oil of Pteronia incana was collected and was investigated on a monthly basis using GC-MS. The oil volume and its constituents vary greatly with different time of sampling and distillation. The oil contains a high percentage of myrcene, α-pinene, β-pinene with sabinene, α-terpinene, 1,8 cineole and limonene.“
[Variation in the essential oil constituents of Pteronia incana (Asteraceae)., Mayekiso, B., Magwa, M. L., Coopoosamy, R. M., African Journal of Biotechnology, Vol.5(12), 2006, 1220-1226.] http://www.academicjournals.org/article/article1379772552_Mayekiso%20%20et%20al.pdf