Isolation and Characterization of a Burkholderia sp. USM (JCM15050) Capable of Producing Polyhydroxyalkanoate (PHA) from Triglycerides, Fatty Acids and Glycerols

Abstract

A consortium of microorganisms from oil polluted wastewater sample was cultivated to promote polyhydroxyalkanoate (PHA) accumulation before subjecting the mixed cultures to sucrose density gradient ultracentrifugation. This resulted in the fractionation of the bacterial cells according to their physical features such as size, morphology and/or densities. An isolate was identified as Burkholderia sp. USM (JCM15050), which was capable of converting palm oil products [crude palm kernel oil (CPKO), palm olein (PO), palm kernel acid oil (PKAO), palm stearin (PS), crude palm oil (CPO), palm acid oil (PAO) and palm fatty acid distillate (PFAD)], fatty acids and various glycerol by-products into poly(3-hydroxybutyrate) [P(3HB)]. Up to 70 and 60 wt% of P(3HB) could be obtained when 0.5%(v/v) CPKO and glycerol was fed, respectively. Among the various fatty acids tested, lauric acid followed by oleic acid and myristic acid gave the best cell growth and PHA accumulation. Compared to Cupriavidus necator H16, the present isolate showed better ability to grow on and produce PHA from various glycerol by-products generated by the palm oil industry. This study demonstrated for the first time an isolate that has the potential to utilize palm oil and glycerol derivatives for the biosynthesis of PHA.