Extraction improvement of water-soluble compounds from Arthrospira platensis through the combination of high-shear homogenization and pulsed electric fields

The use of a mechanical pre-treatment such as high-shear homogenization (HSH - 20,000 rpm, 96 kJ/kgSUSP) in combination with pulsed electric fields (PEF - 20 kV/cm, 100 kJ/kgSUSP) was proposed to selectively and efficiently recover water-soluble proteins, carbohydrates, and C-phycocyanin from A. platensis suspensions during water extraction (25 °C, 3 h). Efficiencies of combined treatment (HSH + PEF) were compared with those of individual high-shear homogenization and pulsed electric fields treatments. The high-shear homogenization treatment promoted the breakage of microalgal trichomes, whereas pulsed electric fields treatment induced only the permeabilization of cell membranes, without affecting cell size and morphology. Combined treatments synergistically increased the extractability of water-soluble proteins and C-phycocyanin from A. platensis, as compared with individually applied treatments, while an additive effect was detected in the recovery of carbohydrates. The combination of high-shear homogenization and pulsed electric fields treatments in a cascade approach allowed reducing the specific energy requirement for protein recovery to lower values than for individual treatments or full cell disruption techniques, such as high-pressure homogenization (HPH).