Ultrasound and supercritical fluid extraction of phytochemicals from purple tamarillo: optimization, comparison, kinetics, and thermodynamics studies.

The parameters for extraction of phenolic compounds and anthocyanins in purple tamarillo using supercritical fluid (SCFE) and ultrasound-assisted extraction (UAE) techniques were optimized. Optimizations of extraction techniques were done using Box-Behnken design in response surface methodology. Based on the total phenolic content, the experimental range for the independent variables in SCFE was set at 30 to 60min, 40-60°C, and 150 to 180 bars of pressure (TPC). Similarly, for UAE, the selected independent variables were 10-30min time, 40-60°C temperature and 20-60% amplitude. The optimized conditions for SCFE were determined to be 49.42min, 49.28°C and 176.63 bar pressure, and at the optimized parameters, the TPC was 16.12mg GAE/g and anthocyanins was 0.62mg C3G/g in the extract. The optimized parameters for UAE were 19.14min, 51.53°C, and 50.53% amplitude, which yielded 21.06mg GAE/g TPC and 0.71mg C3G/g anthocyanins. Four phenolic acids (gallic acid, chlorogenic acid, caffeic acid, and p-coumaric acid) and three anthocyanins (delphinidin-3-O-rutinoside,...