polyhydroxyalkanoates is an intracellular polymer that is biologically synthesized by microorganisms as carbon and energy reserve material . this biodegradable material has properties similar to petrochemical based thermoplastics . currently methods of pha extraction and purification from bacterial suspension use solvent or halogenated - based approaches which are costly and pose severe environmental damage . this invention describes a combined treatment of alkaline and homogenization for extracting and purifying pha , with higher pha purity and recovery .