Optimization of Oil Production from Cassava Pulp and Sugarcane Bagasse Using Oleaginous Yeast

Microbial oil is one of alternative sources for biofuel and value-added chemical production in biorefining process of lignocellulosic biomass. The bottleneck of this process is the low conversion rate of lignocellulose biomass to the target product. This research aims to optimize microbial oil production as raw material for biorefining process from agricultural waste by using Plackett-Burman (PB) design and Response Surface Methodology (RSM). Acid-hydrolysates of cassava pulp and sugarcane bagasse were converted to bio-oil by fermentation activities of two oleaginous yeasts, designated as MSU2 and Ka28. The fermentation parameters were screened by PB design to identify their impacts on oil yield, and the condition of each parameter was optimized by RSM to maximized oil yield. The predicted optimal condition obtained from RSM provided the highest lipid yield at 34.56 and 21.85% from hydrolysates of cassava pulp and sugarcane bagasse, respectively. Then, fatty acid compositions in oil were analyzed by GCMS, and our results demonstrated that palmitic acid and oleic acid were the major constituents at 72.95 and 195.01 mg/g-crude lipid, respectively. These fatty acid distribution profiles were suitable for application in biodiesel production and suggested the utilization of agricultural waste in biorefining process.