Transformation of Palm Oil Mill Effluent to Terpolymer Polyhydroxyalkanoate and Biodiesel Using Rummeliibacillus pycnus Strain TS8

This study aimed to transform wastewater from palm oil mill to the valuable products, especially the terpolymer PHA and biodiesel using Rummeliibacillus pycnus TS8. The cultivation of R. pycnus TS8 in POME was conducted in a 1-L aeration reactor. The optimization of bioproducts production was investigated by a statistical method with the central composite rotatable design. The result found that the highest cell dry weight (CDW) and bioproduct accumulation was obtained at the C/N ratio, aeration rate and phosphorus addition of 10, 1.00 vvm and 0.10 g/L, respectively. Moreover, R. pycnus TS8 accumulated P (3HB-co-3HV-co-3HHx) with 42.8 mol% 3HB, 34.9 mol% 3HV and 22.38 mol% 3HHx. In addition, R. pycnus TS8 also accumulated lipid, especially oleic acid (59.5 % CDW). In addition, the experiment was examined in a 72-L bioreactor to determine the properties of PHA and further used as feedstock for biodiesel production. Afterward, biomass and bioproducts were recovered. The terpolymer PHA and intracellular fatty acid were extracted. The characteristics of terpolymer showed that T-g, T-m, tensile strength, Young's modulus and elongation at break were -21 degrees C, 147 degrees C, 27.67 MPa, 1260 MPa and 11.7 %, respectively. The bioproducts were hydrolyzed to fatty acid methyl ester (FAME) with a heating value, flash point and pour point of 32.9 kJ/g, 132 degrees C and 7 degrees C, respectively. The results illustrated that the properties of terpolymer PHA and FAME produced from this study showed a possibility for further application in biopolymer and biodiesel.