Chemical composition and antimicrobial activity of the essential oil of <i>Amomum tsao‐ko</i>

Abstract

Abstract BACKGROUND: The chemical composition of the essential oil obtained by hydrodistillation from the dried fruits of Amomum tsao‐ko was analysed by gas chromatography/mass spectroscopy (GC/MS). The antimicrobial activity of the oil was evaluated against 16 micro‐organisms using agar disc diffusion and broth microdilution methods. RESULTS: Seventy‐three compounds, constituting about 97.56% of the total oil, were identified. The main components were 1,8‐cineole (45.24%), ρ‐propylbenzaldehyde (6.04%), geraniol (5.11%), geranial (4.52%), α‐terpineol (3.59%) and α‐phellandrene (3.07%). The essential oil showed a broad spectrum of antimicrobial activity against all the tested micro‐organisms, including Gram‐positive and Gram‐negative bacteria, and fungi. The oil exerted the strongest bactericidal activity against Staphylococcus aureus CCTCC AB91118, with minimum inhibitory and bactericidal concentrations of 0.20 g L −1 . CONCLUSION: Our study suggests that the Amomum tsao‐ko essential oil could be one of new medicinal resources for antibacterial and antifungal agents. Copyright © 2008 Society of Chemical Industry