Nanocomposite Zinc Oxide-Chitosan Coatings on Polyethylene Films for Extending Storage Life of Okra (Abelmoschus esculentus)

Abstract

Efficiency of nanocomposite zinc oxide-chitosan antimicrobial polyethylene packaging films for the preservation of quality of vegetables was studied using okra Abelmoschus esculentus. Low density polyethylene films (LDPE) coated with chitosan-ZnO nanocomposites were used for packaging of okra samples stored at room temperature (25 °C). Compared to the control sample (no coating), the total bacterial concentrations in the case of chitosan and nanocomposite coatings were reduced by 53% and 63%, respectively. The nanocomposite coating showed a 2-fold reduction in total fungal concentrations in comparison to the chitosan treated samples. Results demonstrate the effectiveness of the nanocomposite coatings for the reduction of fungal and bacterial growth in the okra samples after 12 storage days. The nanocomposite coatings did not affect the quality attributes of the okra, such as pH, total soluble solids, moisture content, and weight loss. This work demonstrates that the chitosan-ZnO nanocomposite coatings not only maintains the quality of the packed okra but also retards microbial and fungal growth. Thus, chitosan-ZnO nanocomposite coating can be used as a potential coating material for active food packaging applications.

Chitosan Nanocomposite Coatings for Food, Paints, and Water Treatment Applications

“…Nano-sized fillers can be either inorganic or organic materials, such as clay (e.g., montmorillonite), natural antimicrobial agents (e.g., nisin), metal (e.g., silver, gold), and metal oxides (e.g., zinc oxide (ZnO), titanium dioxide (TiO 2 )), to be the material of choice due to its antimicrobial activity, thermal stability and ability to improve mechanical properties of biopolymer films [147,149,153,[155][156][157]. Chitosan-ZnO hybrid coatings on polyethylene films have been reported to reduce growth of pathogenic bacteria and fungi [85], as well as increase the shelf life of okra (Abelmoschus esculentus) vegetables [158]. Zhang et al developed a chitosan-TiO 2 composite film for the packaging of red grapes and evaluated antimicrobial activity against food-borne pathogenic microbes, namely E. coli, S. aureus, Candida albicans, and Aspergillus niger [147].…”

Application of ZnO-nanoparticles to manage Rhizopus soft rot of sweet potato and prolong shelf-life

“…ZnO nano-treatment also appears to have a positive impact on the quality of strawberry fruit during storage (Sogvar et al, 2016). Al-Naamani et al (2018) successfully developed chitosan-ZnOnanocomposite as a coating material, which not only kept the quality of packed okra from deteriorating but also reduced microbial growth. Therefore, the main goal of the research presented here was to assess the effects of ZnO-NPs coatings on the development of Rhizopus soft rot of sweet potato in order to control the disease and prolong the shelf-life of the produce during storage.…”

Combined effect of zinc oxide nano particle incorporated chitosan for better antimicrobial activity towards wound healing

“…Similarly, Padmavathy and Vijayaraghavan (2008) prepared different size of nanoparticles and proved that nanoparticle sizes were inversely related to the Sathiya et al (2018) and they concluded that production of reactive oxygen species (ROS) would be a major reason for antibacterial activity. Similarly, Al-Naamani et al (2018) reported that higher reduction in bacterial and fungal was observed in ZnO-NP-CS coated package film thus extended the shelf life of Okra (Abelmoschus esculentus) for four more days. It has been reported that chitosan was more active against gram negative bacteria than gram positive bacteria (Goy et al, 2009).…”