Extraction of bioactive compounds from feijoa (Acca sellowiana (O. Berg) Burret) peel by low and high-pressure techniques

This work aimed to obtain feijoa peel extracts by means of high-pressure and sustainable techniques, such as the Pressurized Liquid Extraction (PLE) and the Supercritical Fluid Extraction (SFE). These extraction techniques were compared with low-pressure techniques in terms of global yield, total phenolic content (TPC), antioxidant and antibacterial activities. PLE presented the most remarkable results of global yield, TPC and antioxidant activities. On the other hand, the SFE extract (300 bar, 55 °C and 5% ethanol) was the only one to have presented both bacteriostatic and bactericidal effects against typical foodborne pathogens, at 6750 and 13500 μg·mL−1, respectively. Finally, ferulic, gallic and ellagic acids were identified by Liquid chromatography-mass spectrometry (LC-ESI-MS/MS) as the major phenolic compounds found in feijoa peel extracts. The results showed that the use of high-pressure techniques enhanced the extraction of high valuable compounds from feijoa peel, an industrial food waste.