Anti-Yeast Synergistic Effects and Mode of Action of Australian Native Plant Essential Oils

Yeasts are the most common group of microorganisms responsible for spoilage soft drinks and fruit juices due to their ability withstand juice acidity pasteurization temperatures resist action weak-acid preservatives. Food industries interested in application natural antimicrobial compounds as an alternative solution problem. This study attempts investigate effectiveness three Australian native plant essential oils (EOs) Tasmanian pepper leaf (TPL), lemon myrtle (LM) anise (AM) against resistant yeasts, identify major bioactive elucidate anti-yeast mode action. The minimum inhibitory concentration (MIC), fungicidal (MFC) bactericidal (MBC) were assessed EOs yeasts (Candida albicans, Candida krusei, Dekkera anomala, bruxellensis, Rhodotorula mucilaginosa, Saccharomyces cerevisiae, Schizosaccharomyces pombe, Zygosaccharomyces bailii rouxii) bacteria (Staphylococcus aureus Escherichia coli). showed antibacterial activity at concentrations ranging from 0.03–0.07 mg/mL 0.22–0.42 TPL 0.07–0.31 0.83–1.67 LM, respectively. main identified polygodial TPL, citral (neral geranial) LM anethole AM. No changes MICs observed sorbitol osmotic protection assay but found be increased ergosterol binding after addition exogenous ergosterol. Damaging yeast cell membrane, channel formation, organelles ion leakage could EOs. studied potential antimicrobials that used beverage food industry causing yeasts.