Fabrication of volatile compounds loaded-chitosan biopolymer nanoparticles: Optimization, characterization and assessment against Aspergillus flavus and aflatoxin B ₁ contamination

The study demonstrates the use of chitosan as a carrier agent of designed antifungal formulation (CME 4:1:1) based on a combination of plant compounds such as trans- cinnamaldehyde (C), methyl eugenol (M), and estragole (E). The formulation was encapsulated inside the chitosan biopolymer nanomatrix (Ne-CME) and characterized by SEM, FTIR, and XRD. The Ne-CME exhibited enhanced antifungal and aflatoxin B₁ inhibitory effect compared to the individual compounds and unencapsulated form. Ne-CME (0.04 μl/ml) caused significant protection of Piper longum fruit from fungal (90.05%) and aflatoxin B₁ (100%) contamination and had no significant negative effects on its nutritional properties. In addition, the probable antifungal mechanism of Ne-CME was investigated using in-silico (effect on Omt-1 and Vbs structural genes of AFB₁ biosynthesis) and biochemical (perturbances in the cell membrane, carbohydrate catabolism, methyl-glyoxal, mitochondrial membrane potential, and antioxidant defense system) assay.

Keywords: Antifungal; Chitosan; Plant-based compounds.