Phenolic compounds from passion fruit rinds using ultrasound-assisted pressurized liquid extraction and nanofiltration

Ultrasound-Assisted Pressurized Liquid Extraction (UAPLE) and Nanofiltration (NF) were performed in 70% ethanol to recover and concentrate bioactive compounds from passion fruit rinds. Polyamide Thin-Film Composite membranes with nominal MWCO between 150 and 300 Da provided good retention of phenolic compounds (74-89%) and antioxidant capacity (84-96%) with a maximum mass concentration factor 1.4. The membrane surface showed particle deposition and fouling after filtration using AFM, SEM and FTIR, resulting in reductions of permeate mass fluxes of 50-57%. Isoorientin was the main phenolic compound found in the retentates. Integrated UAPLE and NF is a promising process to recover and concentrate phenolic compounds from passion fruit rinds.