Ultrasonic-Assisted Synthesis and Cytocompatibility Assessment of TiO2/SiO2 Nanoparticles-Impregnated Gum Arabic Nanocomposite: Edible Coating of Dates for Shelf-Life Extension.

Abstract

The post-harvest management of fruit is crucial to preventing its decay and loss. Generally, edible coatings are applied to fruit to avoid decay and microbial contamination. We have used ultrasonication to synthesize TiO₂ and Pennisetum glaucum residue-derived biosilica embedded in gum arabic nanocomposite. The SiO₂/TiO₂/gum arabic nanocomposite morphological and crystalline features were investigated using a scanning electron microscope and X-ray diffractometer, respectively. The SiO₂/TiO₂/gum arabic cytocompatibility was assessed using cell viability and microscopic assay. The SEM images revealed that 70-90 nm biosilica and 70-100 nm TiO₂ nanostructures were present on the gum arabic. According to MTT assay and microscopic examination results, SiO₂/TiO₂/gum arabic do not inhibit cell viability and modulate cellular structural features; it inferred that SiO₂/TiO₂/gum arabic possess good cytocompatibility on human mesenchymal stem cells even up to 400 µg/mL. The date fruits were immersed in SiO₂/TiO₂/gum arabic-based coating mixtures and stored at 6 °C for 4 weeks. When date fruits were examined during storage, it was found that the applied coatings contributed to maintaining physicochemical features (e.g., color and texture). These findings suggest that the SiO₂/TiO₂/gum arabic-based coating can be applied to extend the shelf life of dates.