Antifungal effects of seven plant essential oils against Penicillium digitatum

Abstract

Abstract Background Research interest in plant essential oils has increased significantly due to their natural properties and consumer demand for safer methods of food preservation. Plants produce large amounts of secondary metabolites, which have potential activity against fungal pathogens. This study aimed at screening essential oils for their antifungal effects on citrus against Penicillium digitatum, morphological effect and finally determine which essential oils are the most effective. Results The EC50 of seven selected cinnamon (0.424 μL/mL), patchouli (0.513 μL/mL), vetiver (0.612 μL/mL), dill (1.597 μL/mL), origanum (1.971 μL/mL) and ylang (2.214 μL/mL) was determined. In addition, cinnamon substantially reduced sporulation (100%) followed by patchouli (86.02%), vetiver (82.73%), and chamomile (79.04%), respectively. Our GC–MS result determined variance in concentration of essential oils compound composition. The total compound composition in all seven essential oils > 1% was found to be 3 in cinnamon, 5 in dill, 10 in origanum, 13 in ylang, 11 in patchouli, 9 in chamomile and 16 in vetiver. Addition of essential oils significantly altered fungal morphology by scanning electron cryomicroscopy. Patchouli and origanum showed broken hyphae while there was an indication of severe deformation and collapse of spores in cinnamon and chamomile. Conclusion Based on our findings, we report that these essential oils could potentially be applicable in controlling P. digitatum with reduced concern for human health, environmental contamination and possibly replacement of synthetic treatments. Graphical abstract

Keywords

• Penicillium digitatum
• Essential oil
• Antifungal
• Sporulation
• Inhibition
• Cryo-SEM