β-Cyclodextrin/Nerolidol Inclusion Complex as a Potential Ecofriendly Antifungal System against Botrytis cinerea in Postharvest Strawberries

Abstract

β-Cyclodextrin (β-CD) encapsulation may offer a strategic approach to overcome the high volatility of nerolidol (NE) for controlling Botrytis cinerea decay in postharvest strawberries. In this study, a β-cyclodextrin/nerolidol inclusion complex (β-CD/NE) was prepared by freeze-drying to improve the stability and performance of NE. The complex exhibited high complexation efficiency (96.71%) and nanoscale particle size (484.9 nm). FTIR, XRD, and thermal analyses evidenced strong molecular interactions and structural modifications, and an improvement in the thermal stability of the sesquiterpene, while solid-state 13C NMR and SAXS indicates the formation of host–guest inclusion complex through the appearance of characteristic nerolidol resonances and structural modifications in the β-CD matrix. The β-CD/NE showed significantly higher antifungal activity against B. cinerea than free NE in vitro, with inhibition increasing from 17.9% to 65.8% between 200 and 6400 μM, while free NE reached a maximum inhibition of 43.6% at the same concentration range. Strawberries treated with β-CD/NE and stored at 5 °C for 10 days showed a visible decrease of fungal growth and a significant reduction in mass loss compared to untreated fruits, suggesting a high preservation potential. This study advances the application of natural antifungal systems, as the utilization of β-CD/NE inclusion complex as a postharvest antifungal system against B. cinerea in strawberries has not been reported elsewhere.