Studies on cultivation, cell wall development, and gene analysis of marine microalgae pleurochrysis carterae and isochrysis zhanjiangensis

Abstract

In last decade, the mankind has been intensively facing the climate changes in the whole world, because the demand for fuel and greenhouse gas emissions isincreasing dramatically, especially the amount of carbon dioxide. To reduce carbon dioxide in the environment, chemical immobilization, physical fixation, and biofixation are used. To solve this series of problems, except developing hydro energy, sources like wind energy, solar energy, humans began to exploit new alternative energy sources, such as bioethanol and biodiesel. Among biofixation, microalga is generally considered to be the most effective one, because of its faster growth rate (about 8 hours/generation), wider distribution range, and lower production cost. Pleurochrysis carterae is a marine microalga that not only absorbs carbon dioxide by photosynthesis but also absorbs HCO3 - in the ocean and air to synthesize CaCO3 through its unique calcification. Moreover, Pleurochrysis carterae has a lipid content as high as to 33 %, which also contains with high nutritional value. In other words, Pleurochrysis carterae not only has a high potential value in fixing carbon dioxide but also has a great potential in the production of biodiesel and some other high priced products, such as fucoxanthin. Another species of microalga, haptophyte Isochrysis zhanjiangensis, has tremendous potentials in producing high-value products, including fucoxanthin and docosahexaenoic acid (DHA).