Co-precipitation of trans-resveratrol in PHBV using Solution Enhanced Dispersion by Supercritical Fluids technique

Resveratrol is a polyphenolic compound which has shown health beneficial properties related to antioxidant activity. The purpose of this work was to co-precipitate resveratrol in poly(3-hydroxybutyrate-co-3-hydroxyvalerate) by Solution Enhanced Dispersion by Supercritical Fluids technique using a 22 Central Composite Design with 3 central points to evaluate the influence of pressure (8, 11.5 and 15 MPa) and resveratrol concentration (4, 12 and 20 mg(-1)) on percentage of encapsulation, encapsulation efficiency and particle size produced. Encapsulation efficiencies as high as 99.54% were obtained, for which system pressure showed a negative effect (95% confidence level). Particles were mostly spherical with sizes from 390 to 570 nm. Analyses proved that co-precipitation reduced resveratrol crystallinity, improved its antioxidant activity and photo stability. It was shown that particles are free of organic solvents. The release behavior was characterized by an initial burst and a second stationary phase, which enables the use of particles for long-term delivery.