Exploitation of Oil-bearing Microalgae for Biodiesel

As a renewable energy source to replace conventional fossil fuel, biodiesel fuel has been becoming increasingly necessary for the global fuel market. Biodiesel derived from oil crops cannot realistically satisfy even more fraction of the raw material existing costs and soil competitive demand for its growth. Microalgae appear to be the advantage of costs depending on its capability of higher photosynthetic efficiency, larger biomass and faster growth rate compared to that of oil crops. Oil content of many microalgae is usually 80% of its dry weight. Genetic microalgae with oil-bearing productivity by genetic manipulations are capable of making microalgal biodiesel economically competitive with petrodiesel through large-scale production of genetic microalgal biomass. As demonstrated here, the current application of biodiesel at home and aboard are introduced, and the low cost advantage of microalgae as the raw material for biodiesel is analyzed. In addition, the role of key enzymes in microalgal fatty acid biosynthesis and problems in manipulation of lipid production in microalgae via genetic engineering, especially proposals and measures for exploitation and utilization of oil-bearing transgenic microalgae for biodiesel production are also discussed in this review.