THE SEARCH FOR OPTIMALLY BIOACTIVE AUSTRALIAN TEA TREE OIL
This method was used to show that concentrations of 1,8-cineole in excess of the upper limit specified in the Australian Standard are not inhibitory. At concentrations up to 30% cineole appears to be synergistic. Antimicrobial activity decreased only when terpinen-4-ol levels fell below 30%, the minimum limit specified in the standard. Preliminary results also indicated that (+) and (-)-terpinen-4-ol are equally bioactive.