Effect of pomegranate peel extract on shelf life of strawberries: computational chemistry approaches to assess antifungal mechanisms involved

In Italy Botrytis cinerea represents the most significant disease in strawberry crops and causes major quality and quantity losses in postharvest storage. An alternative strategy to the synthetic fungicides in crop defence could be the use of bioactive compounds with high antifungal activity. This research regards the use of Punica granatum peel extract to extend the shelf life of strawberry and the proposal of a possible mechanism for its antifungal activity. In vitro and in vivo tests showed the ability of pomegranate peel extract to control strawberry gray mould. Fourier transform near infrared spectroscopy showed a high correlation between spectra and disease severity then, a putative molecular mechanism for the interaction of punicalagin on ergosterol of fungal membrane was described by means of computational chemistry approaches. Molecular dynamics simulations were performed by using Gromacs to gain multiconformational representations of either punicalagin and an antifungal compound of clinical relevance, i.e. amphotericin B. The use of grid-based procedures, allowed to shed some light on the molecular mechanism featuring the antifungal activity of punicalagin.