Fabrication, characterization, and effectiveness of Rosmarinus officinalis L. essential oil nanoencapsulated by chitosan against Aspergillus flavus and Aspergillus parasiticus in vitro

The current study examined the effectiveness of rosemary essential oil encapsulated in chitosan nanoparticles (REO-CSNPs) using an ionic gelation technique. This green approach aimed to enhance physicochemical stability, antioxidant activity, and antifungal properties. Gas chromatography-mass spectrometry (GC-MS) analysis showed that the primary chemical constituents of REO included 1,8-cineol (31.51 %), α -pinene (22.41 %), levoverbenone (10.67 %), and 3-carene (8.89 %). The optimal mass ratio of REO (0.6) to chitosan (1) was chosen based on the loading capacity and encapsulation efficiency results. FE-SEM images showed that REO-CSNPs were spherical in shape with a size smaller than 100 nm. The successful encapsulation of REO was confirmed by FTIR and X-ray diffraction analyses. REO-CSNPs showed higher antioxidant properties than the REO. According to the findings from the release and kinetic modeling of REO-CSNPs, the primary mechanism involved in the release of REO in phosphate buffer and acetate buffer environments was Fickian diffusion. Encapsulation of REO could increase the antifungal properties. Overall, it can be said that the encapsulating system has a high potential to be used as an alternative to chemical preservatives against fungal contamination by Aspergillus flavus and Aspergillus parasiticus strains in the food industry. • The ion-gelation method was used to incorporate rosemary essential oil (REO) into chitosan nanoparticles. • The developed nanoparticles had spherical shapes with a size of less than 100 nm. • The spectrum of nanoparticles exhibited the characteristic peaks of REO. • Nanoparticles exhibited controlled release of REO in PBS (pH 7) and acetate buffer (pH 3) over 10 days. • The antioxidant and antifungal effectiveness of essential oil was enhanced by encapsulation.