Lipid production from Zygosaccharomyces siamensis AP1 using glycerol as a carbon source

Abstract

Yeasts are considered as potential lipid producer because they are easy to cultivate, able to grow in high cell densities and can produce high concentrations of lipids. Previously we had isolated a promising lipid producing yeast, Zygosaccharomyces siamensis AP1, from wild honey of Central Sulawesi, Indonesia. The strain was able to produce around 19% (w/w biomass) of lipid on glucose. However, its ability to produce lipid on other types of carbon source is still not studied. In this study, we compared the strain ability to produce lipid on glycerol and glucose using different C/N ratio. We also investigated optimum temperature, pH, and growth time for lipid production on glycerol. We found that growing the strain on glycerol with C/N ratio 120 gave the highest lipid content (29.7%). We also found that optimum growth temperature and pH are 30{degrees}C and 5, respectively. Maximum lipid biomass, 0.28 g/L, was produced when the strain was grown in the optimum conditions for 72 hours. In conclusion, our results suggest that glycerol is a potential cheap carbon source for lipid production from Z. siamensis AP1. We suggest further study to increase lipid yield either by fermentation or strain improvement.