Release kinetics and antibacterial activity of curcumin loaded zein fibers

The aim of the present study was to evaluate the release kinetics and antibacterial activities of curcumin (CUR) loaded in zein (zein-CUR) electrospun fibers towards Escherichia coli (E. coli, 8099) and Staphylococcus aureus (S. aureus, ATCC 6538). CUR was successfully loaded in zein fibers by electrospinning technique, and the encapsulation efficiency was close to 100% and the encapsulated CUR still retained its antioxidant capacity. The morphology and size of fibers strongly depended on CUR contents. The interaction between CUR and zein matrix was confirmed to be hydrogen bonding, and the addition of CUR caused a slight increase in the T-g of zein matrix. The electrode process of CUR electrooxidation was diffusion-controlled and could be preceded by chemical reaction. The predominant release of CUR from fibers was Fickian diffusion, and First-order model and Hixson-Crowell model could well describe this diffusion behavior. The zein-CUR fibers showed good antibacterial activity towards S. aureus and E. coli, and the inhibition efficiency increased with the increase of CUR contents. However, the antibacterial activity towards S. aureus was better than that towards E. coli. The study displayed that the zein-CUR fibers might have potential as a promising material for antimicrobial applications to inhibit bacterial growth and propagation in active food packaging. (C) 2016 Elsevier Ltd. All rights reserved.