B-Phycoerythrin (B-PE) is a major light-harvesting pigment of microalgae. Due to 
its high fluorescence efficiency and its intense and unique pink color, it is 
widely used as a fluorescent probe and analytical reagent as well as being 
employed as a natural dye in foods and cosmetics. Tedious methodologies for B-PE 
purification have been published. In this work we present a new, fast, 
preparative and scaleable two-step chromatographic method for B-PE purification 
from the red microalga Porphyridium cruentum. Initially, phycobiliproteins were 
released from the microalga cells by osmotic shock and captured by applying the 
centrifuged cell suspension to a column containing 74 ml Streamline-DEAE 
equilibrated with 50 mM acetic acid-sodium acetate buffer, pH 5.5, using 
expanded-bed adsorption chromatography at an upward flow of 200 cm h(-1). After 
adsorption, washing was carried out in the expanded-bed mode. Having removed 
unbound proteins and cellular debris, the bed was allowed to sediment and a 
B-PE-rich solution was eluted with a downward flow of the same 250 mM buffer. In 
order to obtain pure B-PE, we utilized conventional ion-exchange chromatography 
with a column of DEAE-cellulose loaded directly with the eluate from 
Streamline-DEAE and developed using a discontinuous gradient of acetic 
acid-sodium acetate buffer, pH 5.5. With this new methodology, 66% of B-PE 
contained in the biomass of the microalgae was recovered, a value significantly 
higher than those obtained following other methodologies. The B-PE purity was 
tested using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 
spectroscopic characterization.