Preparation and characterization of tea tree oil solid liposomes to control brown rot and improve quality in peach fruit

Tea tree oil liposomes (TTO-LPs) were prepared using thin film dispersion and orthogonal optimization. TTO solid liposomes (TTO-SLPs) were then generated from TTO-LPs by spray drying, using (2-Hydroxypropyl)-β-Cyclodextrin (HP-β-CD) as a drying protective agent. The physical and chemical characteristics of TTO-LPs and TTO-SLPs were determined, and their antifungal activities against Monilinia fructicola were measured. Finally, TTO-SLPs were applied to peaches to test their antifungal effects on fruit during storage. The optimal process parameters for the preparation of TTO-LPs were as follows: TTO concentration, 2 mL L−1; phosphate buffered solution (PBS) pH, 7.1; soybean lecithin-cholesterol mass ratio, 4:1; ultrasonic power, 500 W. With these parameters, encapsulation efficiency reached 81.75%. TTO-LPs exhibited stability and high antifungal activity. Encapsulation into solid liposomes improved the thermal stability of TTO and maintained their antifungal properties. TTO-SLPs inhibited postharvest brown rot, preserving fruit quality after harvest. TTO-SLPs therefore offer a potentially efficient biological method for controlling brown rot and quality decline of postharvest peach fruit, without the adverse environmental effects associated with synthetic fungicides.