Production of biodiesel from carbon sources of macroalgae, Laminaria japonica

•This is the first demonstration of microbial oil production by using macroalgae.•Oleaginous yeast Cryptococcus curvatus was used for microbial oil production.•Carbon sources were all derived from Laminaria japonica.•No addition of any other nutrients or synthetic medium was used.•The composition of the fatty acids was found similar to vegetable oils.

As aquatic biomass which is called “the third generation biomass”, Laminaria japonica (also known as Saccharina japonica) consists of mannitol and alginate which are the main polysaccharides of algal carbohydrates. In this study, oleaginous yeast (Cryptococcus curvatus) was used to produce lipid from carbon sources derived from Laminaria japonica. Volatile fatty acids (VFAs) were produced by fermentation of alginate extracted from L. japonica. Thereafter, mannitol was mixed with VFAs to culture the oleaginous yeast. The highest lipid content was 48.30%. The composition of the fatty acids was similar to vegetable oils. This is the first confirmation of the feasibility of using macroalgae as a carbon source for biodiesel production.