Antibacterial activity of essential oils from Brazilian plants and their major constituents against foodborne pathogens and spoilage bacteria

This study aimed at determining antibacterial activities of three essential oils (EOs) and their major constituents against foodborne pathogenic bacteria and food spoilage ones. The EOs were tested by the broth microdilution method on 96-well microplates, followed by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) (mu g/mL) determination. EOs from Psidium cattleianum Sabine, Cryptocarya aschersoniana Mez. and Ocotea dispersa Nees (Mez.) leaves showed strong antibacterial activity since their MIC and MBC values ranged between 20 and 250 mu g/mL. Good activity of EOs under analysis can be mostly attributed to high concentrations of viridiflorol, limonene and alpha-eudesmol. EOs were analysed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography with flame ionization detector (GC-FID). The three major commercial terpenes (viridiflorol, limonene and alpha-eudesmol) were evaluated individually and revealed MIC and MBC values between 20 and 62.5 mu g/mL. The findings may serve as an important natural alternative to prevent bacterial growth in food products.