Phytochemistry of the essential oil of Melissa officinalis L. growing wild in Morocco: Preventive approach against nosocomial infections

Objective To determine the phytochemical characterization and antibacterial activity of Melissa officinalis essential oil against bacteria responsible for nosocomial infections. Methods The phytochemical characterization of essential oil was evaluated using gas chromatography-flame ionization detector and gas chromatography-mass spectrometer analysis. Antibacterial activity of the oil was tested against four bacterial strains responsible for nosocomial infections: Pseudomonas aeruginosa , Klebsiella pneumonia , Staphylococcus aureus and Citrobacter koseri using disc diffusion method. Results Thirty three components were identified representing 89.30% of the total oil composition. The yield of essential oil was 0.4% and the predominant components were citronellal (14.40%), isogeraniol (6.40%), geraniol acetate (10.20%), nerol acetate (5.10%), caryophyllene (8.10%) and β-caryophyllene oxide (11.00%). Antibacterial activity of the oil showed the higher activity against all bacterial strains tested. Conclusions The essential oil extracted from lemon balm can be used to clean the environment of reanimation polyvalent and anaesthesia service.