Antifungal Effects of Zataria multiflora Essential Oil on the Inhibitory Growth of some Postharvest Pathogenic Fungi

Abstract

The present study aimed to determine minimum inhibitory concentration and minimum fungicidal concentration of the essential oil of Zataria multiflora to control Alternaria solani, Rhizoctonia solani, Rhizopus stolonifer, Aspergillus flavus, Aspergillus ochraceus and Aspergillus niger. The essential oil of Zataria multiflora was tested in vitro on PDA (malt extract agar medium) with eight concentrations: 0, 10, 50, 100, 200, 300, 400, 500, 600, 700, 800, 900 and 1000 ppm. This investigation followed the completely randomized design (CRD) with three replications. GC-MS evaluations of the essential oil revealed that thymol (35%), carvacrol (34%), cymene-p (9.89%), gamma-terpinene (5.88%) and alpha-pinene (4.22%) were the main compounds of Zataria multiflora oil. The results showed that the essential oil of Zataria multiflora has antifungal activity; the lowest inhibition (75%) was observed in the A. niger, while the highest inhibition (95.3%) was observed in A. solani. Minimum inhibitory concentration for A. solani, R. solani, R. stolonifer, A. flavus, A. ochraceus and A. niger was 200, 200, 200, 300, 300 and 200 ppm respectively. In addition, the present results showed that minimum fungicidal concentration (MFC) for A. solani, R. solani, R .stolonifer, A. niger and A.ochraceus was 600, 400, 300, 900 and 700 ppm respectively and none of the tested concentrations were fatal for A. flavus. A. solani and R. solani showed a strong sensitivity to Zataria multiflora essential oil at all concentrations. Findings of the current study suggest that essential oils of Zataria multiflora could be used for control of postharvest phytopathogenic fungi on fruits or vegetables.