Adsorptive recovery and purification of prodigiosin from methanol/water solutions of Serratia marcescens fermentation broth

The use of macroporous polymeric adsorption resins for the recovery and purification of prodigiosin from fermentation broth of Serratia marcescens SMDR was systematically studied, in which the broth was pretreated by coagulation with alum and the resulting precipitate was leached by methanol/water solution. Of the seven resins tested, Diaion HP-20 resin was selected considering the adsorption and desorption abilities for prodigiosin at the same time. The optimal compositions of liquid phases for adsorption and desorption were also examined. Batch experiments were performed at 15 - 35°C by varying initial prodigiosin concentration in solution (0.05 - 0.5 mmol/L), in which molar fraction of each component in the solution was kept constant. The Freundlich and Langmuir equations were used to describe adsorption isotherms and the related thermodynamic functions were also determined. Fixed-bed experiments were finally conducted to obtain the breakthrough characteristics for the adsorption and desorption of prodigiosin. Under optimized conditions, a purification factor of prodigiosin of 11.4 could be obtained from the pretreated broth after one adsorption-desorption run in fixed bed. The present results had demonstrated the promising potential of HP-20 resins for the recovery and purification of prodigiosin from methanol/water solution of Serratia marcescens fermentation broth.