Evaluación in vitro de la actividad fungistática del aceite esencial de mandarina sobre el crecimiento de Penicillium sp. Evaluation in vitro of the fungistatic activity of the mandarin essential oil on the growth of Penicillium sp.

The fungi Penicillium digitatum and P. italicum represent the main global economic loss to the citrus industry during postharvest stage. Nowadays, the use of fungicides is increasingly restricted due to their carcinogenic, teratogenic, high residuality, long degradation period, environmental contamination, increased pathogen resistance, among others. Natural antimicrobial compounds could be a safe and viable option to minimize disease losses facing the industry. In this study, we evaluated in vitro the activity of tymol, carvacrol and commercial mandarin oil (Italian Mandarin) at concentrations of 40 and 50 ppm using the agar diffusion method and microbiological testing. All the essential oils evaluated for both fungi, showed an inhibition rate between 50% and 100%, and the effect was higher at doses of 50 ppm. This effect was followed by inhibition of sporulation and germination. Carvacrol showed the higher antifungal activity for both fungi studied. P. digitatum showed a greater sensitivity to the effect of the essential oils evaluated compared to P. italicum. Commercial mandarin essential oil can be an alternative to the control of postharvest diseases caused by Penicillium sp. in plant products.