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