Nonionic surfactants induced cloud point extraction of Polyhydroxyalkanoate from Cupriavidus necator

Polyhydroxyalkanoate synthesized by Cupriavidus necator DSM 428 was purified from the crude fermentation broth as such by performing nonionic surfactants (Triton X100, Triton X114 & Tergitol 6) induced cloud point extraction. Polyhydroxyalkanoate was extracted into the micelle-rich bottom phase (coacervate phase), while most of the cellular impurities partitioned into the aqueous phase. Cloud point temperatures and the extraction efficiency of different cloud point systems were studied at different pH value and in the presence of additives. Maximum extraction of biopolymer was achieved (recovery of 84.4%) with a purity of 92.49% at 3 pH with the addition of 0.1 M ammonium chloride in the mixed surfactant system at a reduced cloud point temperature of 33°C.