Volatilome Analyses and In Vitro Antimicrobial Activity of the Essential Oils from Five South African Species.

genus was used in folk South African medicine to treat various human disorders. As a part of our on-going research addressing the exploitation of South African plants belonging to this genus, five species were investigated for their volatile and antimicrobial activities. The volatile organic compounds (VOCs) and the essential oils (EOs) were analysed by gas chromatography mass spectrometry (GC-MS). Microdilution was the method used for assessing both antimycotic and antibacterial activities, which was also tested by Kirby-Bauer agar disc diffusion. Total monoterpenes (TMs) dominated the VOCs of four species ( (70.6%), (79.3%), (84.5%), and (57.0%)). and EOs showed the predominance of TMs (68.2% and 84.5%, respectively), while and EOs were characterized by the prevalence of TSs (86.5% and 43.6%, respectively). EO evidenced a similar amount of both TMs (49.5%) and TSs (46.4%). was more sensitive to these EOs. The lowest minimum inhibitory concentration (MIC) was observed with and EOs (0.25%). and had a good effect on (MIC 5%). These findings open new perspectives for the exploitation of these natural compounds for application in cosmetics and pharmaceutics.