High pressure disruption: a two-step treatment for selective extraction of intracellular components from the microalga Porphyridium cruentum

The microalga Porphyridium cruentum is known to produce many components of interest. One of them is B-Phycoerythrin (B-PE), a water-soluble intracellular pigment used as an immunofluorescent probe. Current methods to extract this molecule involve total cell disruption and lead to a mix of all the water-soluble components. Subsequently, the pigment purification is very complex. An alternative approach to extract B-PE selectively and thus simplify the purification procedure has been developed using a high-pressure cell disrupter. Different pressures (from 27 to 270 MPa), extracting mediums (distilled water and original microalgae culture medium), and numbers of passages (1 to 3) have been tested. Proteins are selectively more extracted than B-PE at low pressure in original medium. It is thus possible to remove part of the intracellular proteins in a first step and then recover enriched B-Phycoerythrin fraction at higher pressure in distilled water.