Supercritical Precipitation of PHB as a Potential Carrier for Antioxidant Delivery

FACUNDO MATTEA; VALENTINA SOSA; MATÍAS DALMASSO; JAVIER GALFIONI; JOAQUÍN OREJAS

Firenze

Congreso; The 12th European Congress of Chemical Engineering - ECCE 12; 2019

In this study, the use of supercritical carbon dioxide to precipitate poluhydroxybutyrate (PHB) from solutions prepared in 1,3 - dioxolane and dichloromethane were initially investigated obtaining different morphologies and particle characteristics depending on the solvent and process variables. Then the coprecipitation of PHB and antioxidants extracted from green tea by microwave-assisted extraction and ultrasound-assisted extraction was carried out at different pressures and temperatures obtaining ellipsoidal smooth particles with mean sizes in the order of hundreds of nanometers but agglomerated into particles within the microscale. the best conditions were obtained by using 1,3-dioxolane, a pressure of 120 bar and a temperature of 40°C. WIth those operational conditions, hollow elipsoidal particles with mean sizes of 420 nm containing 97% of the green tea extract were produced. The antioxidant capacity of the coprecipitated exhibited a sustained release profile, providing a low concentration for very long periods of time. However, the system must be improved to tune the release depending on the desired concentration in aqueous solutions.