Because mannitol is water-soluble whereas alginate is not, a stepwise process was used (Fig. 1): first, alginate was fermented under anaerobic condition to obtain VFAs which can be used by C. curvatus , then the VFAs were mixed with mannitol and then added to the lipid-producing fermentor. It was the first time to produce lipid by oleaginous yeast only using the L. japonica as the sole carbon source without adding any other nutrients.