Characterization of resistance to essential oils in a strain of Pseudomonas aeruginosa (VR-6).

VR-6, a strain of Pseudomonas aeruginosa, harboured a plasmid and was not inhibited by 20 μl ml -1 of essential oils (eucalyptus, lemongrass, palmarosa, and peppermint). On treatment with acridine orange, a clone VR-6-AO-1 was obtained which was susceptible to 16.6 μl ml -1 of eucalyptus or palmarosa oil. The plasmid DNA content of this clone was similar to the parent strain