Ultrasonic preparation of citral/hydroxypropyl-β-cyclodextrin inclusion complex: Application as a potential antifungal preservative in strawberry storage

In this study, an inclusion complex (IC) of citral (CIT) within hydroxypropyl-beta-cyclodextrin (HP beta CD) was prepared by ultrasound technique. The structural characterization, thermal stability, phase solubility, antifungal properties and applications of CIT/HP beta CD-IC in strawberry storage were investigated. The results showed that CIT/HP beta CD-IC was successfully formed and had better thermal stability than CIT only. The apparent stability constant and Gibbs free energy change of the inclusion process was determined to be 142.08 M-1 and 12.87 kJ mol(-1), respectively, by the phase solubility method. The in vitro antifungal tests demonstrated that the IC had a certain antifungal effect against Geotrichum citri-aurantii, with a significant inhibitory effect against the growth of Botrytis cinerea and Alternaria alternata at concentrations above 5 mg mL(-1). Additionally, the treatment of CIT/ HP beta CD-IC on strawberry effectively reduced the decay rate and decrease of weight loss, soluble solids, firmness, and pH, thereby extending the shelf life. This research indicated that the ultrasonically synthesized CIT/HP beta CD-IC effectively improved the water solubility and stability of CIT and could be utilized as an antifungal preservative for storage and preservation of strawberry, and potentially other fruits and vegetables.

Automated summary

In this study, an inclusion complex of citral within hydroxypropyl-beta-cyclodextrin was prepared using ultrasound technique. The complex showed improved thermal stability and antifungal properties. Additionally, treatment with the complex effectively extended the shelf life of strawberries.