Optimization and antimicrobial efficacy of curcumin loaded solid lipid nanoparticles against foodborne bacteria in hamburger patty.

The aim of the present study was to design a delivery system of curcumin (CU) loaded solid lipid nanoparticles (CU-CSLNs) for evaluating the antimicrobial properties in hamburger patty. Solid lipid nanoparticle (SLN) was prepared through a homogenizing technique. A response surface methodology was applied to optimize the CU-CSLNs to minimize the particle size (PS), polydispersity index (PDI), as well as to maximize the zeta potential to avoid aggregation of particles. The optimized sample revealed a spherical morphology under scanning electron microscope (SEM) and dynamic light scattering (DLS) with particle sizes of 126.87 ± 0.94 nm and 0.21 ± 0.025 PDI. The zeta potential and encapsulation efficiency (EE %) were found to be -30 ± 0.3 mV and 99.96 ± 0.01%, respectively. The CSLNs exhibited higher in vitro antimicrobial effect (142 µg·ml-1 ) against Staphylococcus aureus and generic Escherichia coli as compared to free CU (1000 µg·ml-1 ). Finally, the CSLNs antimicrobial effect was tested in hamburger patty inoculated with foodborne pathogens during eight days of storage at 4 °C. The results indicated that CSLNs had a higher antimicrobial effect than free CU. This study provides insight into the preparation of the novel antimicrobial nanoparticles for food safety applications.