The antifungal effect against Penicillium italicum and characterization of fruit coating from chitosan/ZnO nanoparticle/Indonesian sandalwood essential oil composites

The properties of an antifungal coating film made from chitosan (CH) combined with zinc oxide nanoparticles (ZNPs) and Indonesian sandalwood essential oil (SEO) were investigated. Incorporation of 0.5% SEO or 0.025% ZNPs plus 0.5% SEO into 0.8% CH coating solution showed outstanding effects on the inhibition of both mycelium growth and spore germination of Penicillium italicum. The antifungal mechanism was explained by measuring the loss of membrane integrity of spores. The antifungal effectiveness was confirmed in vivo by carrying out tests on tangerine fruit. The biocompatibility of these coatings was analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, atomic force microscopy, and fluorescence microscopy. Significant increases in pH, appearance viscosity, and transparency and a decrease in light transmittance were found with 0.8% CH plus 0.025% ZNPs and 0.5% SEO compared with the control. CH films incorporating SEO and ZNPs can be used as an edible film and coating to reduce chemical use.