Phytochemical analysis and biological screening of leaf and twig extracts from Kunzea ericoides

Kunzea ericoides is a member of the Myrtle group of tea trees. Leaf and twig material of K. ericoides was extracted with different solvents to afford terpene (including the essential oil), flavonoid and lipid classes (but no alkaloid class), which were subsequently screened for antibacterial, antitumour, cytotoxic, antioxidant and antiinflammatory activity. Differences were observed in the biological activity for the chemical classes tested, and in general, the leaf extracts were comparatively more bioactive than the twig extracts. The leaf lipid extract was the most bioactive fraction, exhibiting antibacterial, antitumour and antiinflammatory activity. Thin layer chromatography and gas chromatography-mass spectroscopy analysis of each extract revealed previously identified phytochemicals that may be responsible for the observed bioactivities.