In 2018, a study was carried out to see how well eucalyptus oils from certain species in Western Australia worked against bacteria and yeasts. The researchers tested oils from six different types of eucalyptus trees and compared the results to the most common ingredient in eucalyptus oil, 1,8-cineole, also known as eucalyptol.
The findings showed that the oils had varying levels of effectiveness against the organisms tested, with Eucalyptus polybractea and Eucalyptus globulus oils performing the best. Out of all the oils tested, Eucalyptus polybractea oil was the only one that was able to stop the growth of all the organisms at a concentration of 8% or less. The study also found that the effectiveness of the oils varied based on the species of eucalyptus and the type of microorganism.
Eucalyptus polybractea was a significant oil in the study as it showed the highest antimicrobial activity against all test organisms. The results showed that Eucalyptus polybractea oil was the only oil that inhibited the growth of all organisms at a concentration of 8% or lower. This oil was able to inhibit the growth of all 10 organisms tested, making it a promising candidate for further research as a potential antimicrobial agent.
In conclusion, the study showed that some selected Western Australia species of eucalyptus have moderate antimicrobial activity, with the activity varying depending on the species and the type of microorganism. The results suggest that Western Australia eucalyptus oils are a potential source of antimicrobial agents, especially against Gram-negative bacteria. Eucalyptus polybractea oil was found to have the highest antimicrobial activity, making it a promising candidate for further research.
Study Title: Antimicrobial Activity of Several Cineole-Rich Western Australian Eucalyptus Essential Oils
Study Link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6313647