Pulsed Electric Fields assisted extraction of proteins and phycocyanin from Arthrospira platensis biomass: A kinetic study

The objective of this work was the investigation of the kinetics of protein and C-phycocyanin extraction from Arthrospira platensis (Spirulina) biomass assisted by Pulsed Electric Fields (PEF). Fresh, untreated and PEF-treated (7.8 kV/cm, 0–137.6 kJ/kg) biomass was suspended in water and incubated at 30–50 °C for up to 24 h. Protein and C-phycocyanin recovery kinetics exhibited a sigmoidal behavior. The increase in treatment specific energy and incubation temperature up to 40 °C led to significant extraction acceleration. A treatment of 137.6 kJ/kg prior to incubation at 40 °C led to the minimization of protein characteristic incubation time (2.3 h vs. 14.4 h and 10.4 h of untreated sample at 30 and 40 °C, respectively). At 50 °C a significant reduction of the extraction yield was observed, due to the inactivation of the proteolytic enzymes. Higher treatment specific energy led to increased C-phycocyanin purity of the extracts at 40 °C. The maximization of the C-phycocyanin extract purity factor (1.14 vs 0.66 for untreated samples) was achieved with a PEF treatment at 137.6 kJ/kg and incubation at 40 °C for 3 h.