Separation of phycocyanin from Spirulina platensis using ion exchange chromatography

Bioprocess Biosyst Eng (2008) 31:477482 DOI 10.1007/s00449-007-0185-1

ORIGINAL PAPER

Separation of phycocyanin from Spirulina platensis using ion exchange chromatography

Silvana Terra Silveira Luci Kelin de Menezes Quines Carlos Andr Veiga Burkert Susana Juliano Kalil

Received: 2 August 2007 / Accepted: 7 December 2007 / Published online: 25 January 2008 Springer-Verlag 2008

Abstract This paper presents the evaluation of some important parameters for the purication of phycocyanin using ion exchange chromatography. The inuences of pH and temperature on the equilibrium partition coefcient were investigated to establish the best conditions for phycocyanin adsorption. The equilibrium isotherm for the phycocyaninresin system was also determined. The separation of phycocyanin using the Q-Sepharose ion exchange resin was evaluated in terms of the pH and elution volume that improved the increase in purity and recovery. The highest partition coefcients were obtained in the pH range from 7.5 to 8.0 at 25 C. Under these conditions the equilibrium isotherm for phycocyanin adsorption was well described by the Langmuir model, attaining a Qm of22.7 mg/mL and Kd of 3.1 9 10-2 mg/mL. The best conditions for phycocyanin purication using the ion exchange column were at pH 7.5 with an elution volume of 36 mL, obtaining 77.3% recovery and a 3.4-fold increase in purity.

Keywords Phycocyanin Ion exchange

Isotherm adsorption Spirulina platensis

List of symbolsC0 initial phycocyanin concentration in the liquid phase

(mg/mL)

C phycocyanin concentration in the liquid phase(mg/mL)

C* equilibrium phycocyanin concentration in the liquid phase (mg/mL)

P purity ratio (A615/A280)f partition coefcientKd dissociation constant (mg/mL)

PC phycocyanin concentration (mg/mL)

Qm maximum binding capacity of the resin (mg/mL)

Q* equilibrium phycocyanin concentration in the solid phase (mg/mL)

V volume (mL)

Introduction

Phycobiliproteins are water-soluble light-harvesting proteins with uorescent properties derived from cyanobacteria, cryptomonads and red algae [6]. They are divided into three classes based on their adsorption properties: phycoerythrins, phycocyanins, and allophycocyanins. The main function of phycobiliproteins is to participate in the photosynthetic process together with chlorophyll-a and carotenoids [21, 25].

Phycocyanin is a blue pigment present in the cyano-bacteria Spirulina platensis, widely used as a uorescence marker in clinical diagnosis, and also as a dye in the pharmaceutical and cosmetics industries [4]. In Japan, the use of phycocyanin as a food dye has been authorized for products like chewing gums, candies,...