Separation and Purification of Polyhydroxyalkanoates from Newly Isolated<i>Comamonas</i>sp. EB172 by Simple Digestion with Sodium Hydroxide

Abstract

Abstract A simple, mild, and effective process for the recovery of intracellular polyhydroxyalkanoate from a newly isolated gram-negative wild-type bacteria Comamonas sp. EB172 was developed using sodium hydroxide. Various parameters such as sodium hydroxide concentration, digestion time, and temperature were examined for their effect on polyhydroxyalkanoate recovery. The results showed that polyhydroxyalkanoate with 88.6% purity and 96.8% recovery yield were obtained by incubating the dried cells with 0.05 M sodium hydroxide at 4°C for 1 h, followed by purification steps using ethanol and water. Removal of non-polymeric cellular materials from the Comamonas sp. EB172 was increased under alkaline solution as a result of enhanced cell wall permeability. In addition, the presence of glycerol in the polymer suspension proved that saponification of the lipid layer in the bacterial cell wall occurred due to sodium hydroxide reaction. Keywords: Comamonas sp. EB172downstream processingNaOH digestionpolyhydroxyalkanoatespurificationrecovery ACKNOWLEDGEMENTS The financial and technical support received from the Federal Land Development Authority (FELDA), Ministry of Science Technology and Innovation (MOSTI), Malaysia and Japan Society for Promotion of Science (JSPS), and Japan is gratefully acknowledged. Notes Data shown are the means of triplicate tests. Mean data accompanied by different superscript letters are significantly different (Duncan's Multiple Range Test, p < 0.05).