Optimization of critical factors to enhance polyhydroxyalkanoates (PHA) synthesis by mixed culture using Taguchi design of experimental methodology

► Taguchi DOE methodology was applied to optimize mixed culture PHA production. ► Microenvironment (80%) and pH (11%) showed significant contribution in PHA production. ► Glucose, phosphorous, nitrogen and VFA had significant interactive effects. ► Optimization improved PHA production by over 31%. ► PHA production through wastewater treatment significantly reduces the production cost.