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 mu g center dot ml(-1)) against Staphylococcus aureus and generic Escherichia coli as compared to free CU (1000 mu g center dot ml(-1)). Finally, the CSLNs antimicrobial effect was tested in hamburger patty inoculated with foodborne pathogens during eight days of storage at 4 degrees 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.