Tolerance of Pseudomonas aeruginosa to Melaleuca alternifolia (tea tree) oil is associated with the outer membrane and energy-dependent cellular processes.

Objectives: The essential oil of Melaleuca alternifolia (tea tree oil) and its components have antimicrobial activity against a wide range of Gram-positive and Gram-negative bacteria, fungi and viruses. The mechanism(s) by which Pseudomonas aeruginosa NCTC 10662 maintains a decreased susceptibility to tea tree oil and components was investigated.

Results: Ethylene diamine tetraacetic acid enhanced the antimicrobial activity of tea tree oil and terpinen-4-ol against stationary phase P.

Susceptibility of Erysipelothrix rhusiopathiae to antimicrobial agents and home disinfectants.

Aim: Erysipelothrix rhusiopathiae causes the occupationally-related infection erysipeloid in humans, and may be responsible for infections in lobster fishermen in Western Australia. There are little recent data pertaining to antimicrobial susceptibility, or susceptibility to disinfectants that might be used in the environment. The aim of this study was to determine the susceptibility of E.