Lipid Accumulation in the Oleaginous Yeast Lipomyces starkeyi MV-5 Cultured in Sago Media

Biodiesel produced from plant oil, animal fats and microorganisms is a promising alternative to replace fossil fuel. However, since biodiesel feedstock from plant and animal compete with the food production supplies, another possible alternative is to use the oleaginous microorganisms. Among the oleaginous microorganisms, oleaginous yeast Lipomyces starkeyi is of interest as it can accumulate more lipids and utilize the low-valued nutrient source such as the industrial waste. In this study, a mutant strain of L. starkeyi which is L. starkeyi MV-5 was used to compare the lipid production in two different carbon sources; sago effluent and sago starch. Since the starch percentage of sago effluent used was approximately 1.8%, 1.8% sago starch was prepared to compare their efficiency. After 7 days of propagation stage, the optimum growth of L. starkeyi MV-5 was detected at 120 h. In the lipid accumulation stage, sago effluent and 1.8% sago starch were used as the substrate where the highest biomass ofL. starkeyi MV-5 were recorded at 168 hat 1.20 gIL and 1.55 gIL respectively. Whereas, the highest lipid extracted from L. starkeyi MV-5 were 0.25 giL and 0.45 gIL respectively. Phenol-sulphuric acid test was then done to determine the starch consumption of L. starkeyi MV-5. Based on these results, the lipid content ofL. starkeyi MV-5 cultured in sago effluent and 1.8% sago starch were 20.83% and 29.00% respectively. Thus, L. starkeyi MV-5 cultured in 1.8% sago starch gave higher biomass and higher lipid compared to in 1.8% sago effluent