An experimental study of the investigation of post-harvest fungal control potential of natamycin-loaded chitosan nanoparticles: synthesis, characterization, and antifungal activity analyses

Abstract

This study presents the development and characterization of natamycin-loaded chitosan nanoparticles (Nat-Chi-NPs) for post-harvest fungal control. The nanoparticles were synthesized via ionic gelation and characterized using various spectroscopic and physicochemical techniques. The resulting Nat-Chi-NPs exhibited an average particle size of 52.40 nm, a zeta potential of + 13.8 mV, and an encapsulation efficiency of 53.46%. FTIR and UV-Vis analyses confirmed the successful encapsulation of natamycin. A biphasic release pattern was observed, with a cumulative release of 98.82% over 144 h, indicating sustained antifungal activity. In vitro antifungal assays showed that Nat-Chi-NPs inhibited the mycelial growth of Aspergillus niger and Botrytis cinerea by 29.51 and 24.79%, respectively. In situ tests on apple wounds demonstrated a reduction in fungal growth ranging from 24 to 30% at a concentration of 20 mg/L, with protection lasting up to 5 days. These findings highlight the potential of Nat-Chi-NPs as an effective and eco-friendly nanobiotechnological system for the control of post-harvest fungal infections in fruits and vegetables.