Abstract Oils obtained by hydrodistillation from the aerial parts of Monarda citriodora var. citriodora, Myristica fragrans, Origanum vulgare ssp. hirtum, Pelargonium sp. and Thymus zygis were screened for antioxidative properties in a lipid-rich matrix as quantified by spectrophotometry using iron (II) sulphate and 2,2â²-azobis(2-amidinopropane) dihydrochloride as sources of primordial free radicals. Furthermore, the antimicrobial properties of M. fragrans, O. vulgare, Pelargonium sp. and T. zygis were screened against 25 different genera of bacteria selected for their agricultural, economic and health significance. The oils demonstrated a range of bioactive properties, with the oils rich in phenolic monoterpenes (M. citriodora and T. zygis) being particularly active in both antioxidant and antibacterial test systems. Key Word Index: Monarda citriodora var. citriodora Myristica fragrans Origanum vulgare ssp. hirtum Pelargonium sp. Thymus zygis LabiataeGeraniaceaeMyristicaceaeessential oil compositionÎ±-pinenesabineneÎ²-pinenep-cymenecitronellolgeraniolthymolcarvacrol