Extraction of bioactive compounds from Alaria esculenta with pulsed electric field.

There is a growing demand for bioactive compounds derived from green extraction methods from the food and cosmetic industries. Pulsed electric field (PEF)-assisted extraction has been applied for numerous foods but few on macroalgae. The present study examines PEF as part of the extraction process of polyphenols and carbohydrates from the brown macroalga Alaria esculenta. The effect of PEF treatment (0, 720 pulses) and ethanol concentration (0%, 15%) on the extraction of bioactive compounds from Alaria esculenta was assessed. To determine the pigment yield a second extraction was conducted with 60% ethanol or fractionated coconut oil with or without lecithin. The PEF treated aqueous extract had the highest yield for phenolic (10.4 ± 3.7 mg GAE g−1 DW) and carbohydrate content (21.4 ± 1.8 mg GE g−1 DW) as well as ferric reducing activity power and DPPH radical scavenging activity. The 60% ethanol extracts had a higher fucoxanthin content (73 ± 14 mg (100 g)−1 FD pulp) than the oil (2.1 mg (100 g)−1 FD pulp) and oil with lecithin (17 mg (100 g)−1 FD pulp) extracts. We obtained crude aqueous and low ethanolic extracts containing bioactive that show antioxidant activities, with either low temperature or PEF treatment from dried blades of Alaria esculenta. PEF treatment did not influence the pigment extraction with oil or 60% ethanol. [ABSTRACT FROM AUTHOR]