Background: The microorganisms such as Penicillium expansum and Botrytis cinerea are well‐known pathogens in apples and during postharvest. To protect apples from these pathogens, chemical control methods were exercised.
Objective: The main objective of this work was to study the chemical composition, the in-vitro and in-vivo antifungal properties of essential oil and hydrosol extract of Marrubium vulgare.
Methods: In this work, the air-dried aerial parts of Marrubium vulgare were hydrodistilled in a Clevenger-type apparatus. The essential oil and hydrosol extract isolated were analyzed using gas chromatography (GC) and mass spectrometry (GC/MS). The in-vitro antifungal activity of the both extracts was investigated against tree plant fungi using radial growth technique. The effect of the essential oil and hydrosol extract on disease development of apple caused by Penicillium expansum in the in-vivo conditions was assessed.
Results: The essential oil of Marrubium vulgare was characterized principal by E-β-caryophyllene (23.5%), E-β-farnesene (21%), α-humulene (14.8%), β-bisabolene (11.1%), caryophyllene oxide (6.8%) and phytol (3.1%). While, the methyl-eugenol (65.5%), α-Bisabolol (12.5%), linalool (6.5%) and caryophyllene oxide (6.2%) were the major compounds of hydrosol extract. The result of in-vitro antifungal activity of hydrosol extract showed an interesting antifungal inhibition against Botrytis cinerea, Penicillium expansum and Alternaria alternata with percent inhibition ranging from 77% to 89% at low concentration of 0.15 mL/L. The essential oil was found to inhibit the growth of Penicillium expansum in a dose dependent manner, with percentage of inhibition of 100 % at 30 mL/L. Furthermore, essential oil and hydrosol extract have demonstrated promising in-vivo antifungal activity to control infection of apples by Penicillium expansum up to 25th day of storage, compared with the control.
Conclusion: Thus, hydrosol extract of Marrubium vulgare can be used as a potential source to develop cheaper control agents to manage fungal diseases of apple fruits.