trans‐Cinnamaldehyde‐encapsulated zeolitic imidazolate framework‐8 nanoparticle complex solutions to inactivate Escherichia coli O157:H7 on fresh spinach leaves

Abstract

This study synthesized and characterized ZIF-8 nanoparticles encapsulated with trans-cinnamaldehyde oil (TC) and evaluated their antimicrobial effectiveness against Escherichia coli O157:H7 on fresh spinach leaves. The antimicrobial activity of different mass ratios of TC-encapsulated ZIF-8 against E. coli O157:H7 (ATCC 43895) strain was assessed and the best mass ratio of 1:2 TC to ZIF-8 identified. Spinach leaves were treated with (1) 0.5TC@ZIF-8_PL nanoparticle complexes solution, (2) 200 ppm chlorine, (3) free TC, and (4) sterilized distilled water (control). All sample groups were rinsed for 1 min, dried in a biosafety cabinet, weighted, and packed in sterilized Whirl-pk TM Stand-Up sampling bags, and stored at 4 • C for 15 days for shelf life studies. Samples were dipped into a solution of nanoparticles and another group was sprayed. The quality of spinach samples was assessed by monitoring changes in moisture content (MC), water activity (Aw), color, pH, texture (firmness and work), vitamin C content, total carotenoid, and chlorophyll content. Spinach leaves treated with 0.5TC@ZIF-8_PL had less (p < 0.05) water, total chlorophyll, and total carotenoid losses, with minimal changes in pH. However, treatment did not prevent the color degradation (p > 0.05) and adversely affected spinach firmness. The spinach samples treated with 200 ppm chlorine and free TC had higher (p < 0.05) total chlorophyll degradation than the samples treated with the nanoparticles. The mass ratio of TC-encapsulated ZIF-8 must be readjusted to reduce potential toxicity issues while maintaining the antimicrobial properties.

Properties of poly (vinyl alcohol) films with embedded zeolitic imidazolate framework (ZIF‐8) nanoparticles for food packaging applications

“…MOFs are synthesized by assembling metal ions with organic ligands through strong bonds. Their high surface area and porosity for high loading of therapeutic agents, and easy modification of physical and chemical properties through inorganic clusters and/or organic ligands make MOFs promising materials for a variety of applications including energy storage, compound separation, chemical sensing, catalysis, and drug delivery of biomolecules (Cheng et al., 2021; Du et al., 2022; Furukawa et al., 2013; Jia et al., 2020; Kim et al., 2021; Ruyra et al., 2015; Tiwari et al., 2017; Wu et al., 2015; Yang et al., 2022; Zhang et al., 2019; Zhu & Xu, 2014).…”

“…Zeolitic imidazolate framework‐8 (ZIF‐8) is a member of the ZIF family, known for its biocompatible nature, and large, hydrophobic pores that allow it to accommodate considerable amounts of drugs (Luzuriaga et al., 2019; Wu et al., 2015; Yang et al., 2022). The superior stability under aqueous physiological conditions allows ZIF‐8 to avoid premature drug release and increase cellular uptake, helping it as a drug carrier (Ren et al., 2014).…”

“…The effect of ZIF‐8 nanoparticles on the shelf‐life and quality of spinach was evaluated by Yang et al. (2022).…”

“…In brief, all PVA/ZIF-8@TC nanocomposite films with embedded ZIF-8@TC inhibited E. coli MG1655 while the PVA-only film did not. The effect of ZIF-8 nanoparticles on the shelf-life and quality of spinach was evaluated by Yang et al (2022).…”

Fabrication of γ-cyclodextrin-Based metal-organic frameworks as a carrier of cinnamaldehyde and its application in fresh-cut cantaloupes

“…Metal-organic frameworks show advantages over other porous materials in terms of their well-defined porous structure, large surface area, ease of synthesis, and structural diversity. Porous metal-organic framework carriers for incorporation of volatile antimicrobial essential oil components (such as thymol, trans-cinnamaldehyde oil, and carvacrol) have been reported to possess long-term sustained release ( Caamano et al, 2022 ; Liu et al, 2019 ; Wu et al, 2019 ; Yang et al, 2022 ). However, safety concerns about the application of the metal-organic framework in the food industry have been raised due to the presence of heavy metals such as Cd, Cu, and Zn in them ( Pinar Gumus and Soylak, 2021 ).…”