Effect of oleic acid on the release of tetrahydrocurcumin in chitosan-based films

The first objective of this study was to develop chitosan (CH)-carboxymethyl cellulose (CMC) film forming dispersions (FFDs) containing oleic acid for the encapsulation of a hydrophobic active curcumin derivative (tetrahydrocurcumin-THC). The second objective examined the impact of oleic acid on the release of THC and the associated antioxidant and antimicrobial action of CH-CMC-THC films. Oleic acid had a strong negative impact on THC release potentially due to the stability of the THC encapsulation in the oleic acid droplet, as suggested by ATR-FTIR and SEM analyses. The in vitro antifungal activity against Botrytis cinerea, indicated significant antifungal activity of THC and CH-CMC FFD with or without oleic acid. In contrast, in vivo experiments consisting of the CH-CMC-THC FFD coating of blackberries had no effect on the microbial charge irrespective of the oleic acid presence. In addition, the visual appearance of the CH-CMC-THC FFDs coated-blackberries seemed better in the absence of oleic acid.