BIOACTIVITY OF NEW ZEALAND MEDICINAL PLANT ESSENTIAL OILS
The family Myrtaceae was represented by samples of steam-distilled wood of Manuka (Leptospermum scoparium J.R.et G.Forst) and Kanuka (Kunzea ericoides (A.Rich.) J. Thompson) and Leptospermum petersonii Bailey syn. L. citratum from high altitude sites of South Island and the east coast of North Island had different but usually good antibacterial activity with poor antifungal action except for L. citraturn, and variable antioxidant action; strong spasmogenic activity was shown by Kanuka, in contrast to a spasmolytic action of Manuka and L. petersonii. Other oils studied included New Zealand grown Tea tree (Melaleuca alternifolia (Maiden & Betche) Cheel), Totara (Podocarpus totara G. Benn. ex D. Don, Coniferae), which showed good and poor bioactivity respectively, and two species of Eucalyptus which showed variable results. The bioactivity of all these essential oils was compared against that of common herbs, grown locally.