"CONCLUSIONPHB as an intracellular storage material can be generated by a variety of microorganisms.The eco friendly property and wide availability of raw materials drives PHB more popular inusing them as bio-based and biodegradable polyester. It is obvious that a wide variety of carbonsources can be used as raw materials which have been considered as the major cost-absorbingfactors in PHB industry. In this design project, we have chosen cassava starch manufacturingwastewater as raw material for the synthesis of PHB due to its relatively low cost and moreadvantages than using other lignocelluloses materials. A fed-batch fermentation process has beencarried out to fulfill the process of PHB production. Theoretically, the total yield of PHB fromour case study is 1,100 tonnes per year based on the 15t/ha of average annual cassava yield and2 45 km of farm land. 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