ARS | Publication request: Beyond fatty acid methyl esters: Expanding the renewable carbon profile with alkenones from Isochrysis sp.

Submitted to: Energy and Fuels
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 11, 2012
Publication Date: March 12, 2012
Citation: O'Neil, G.W., Carmichael, C.A., Goepfert, T.J., Fulton, J.M., Knothe, G.H., Ling Lau, C., Lindell, S.R., Mohammady, N., Van Mooy, B., Reddy, C.M. 2012. Beyond fatty acid methyl esters: Expanding the renewable carbon profile with alkenones from Isochrysis sp. Energy and Fuels. 26(4):2434-2441.

Interpretive Summary: Biodiesel is an alternative to diesel fuel obtained from petroleum. While it is usually produced from vegetable oils such as soybean oil, or other sources such as animal fats and waste frying oils, new feedstocks have been receiving increasing attention. Among these feedstocks is algae which can potentially produce high amounts of oil. Some algae, however, produce other materials known by their scientific names as alkenones. The properties of alkenones are discussed here and how they may affect the properties of biodiesel obtained from the algae producing them. The alkenones may also be a hitherto unexplored renewable feedstock for products other than fuels.

Technical Abstract: In addition to characteristic fatty acid methyl esters (FAMEs), biodiesel produced from Isochrysis sp. contains a significant amount (14% dry weight) of predominantly C37 and C38 longchain alkenones. These compounds are members of a class of lipids known collectively as polyunsaturated long-chain alkenones (PULCAs) that are produced by a range of other prymnesiophyte taxa. The physical properties of alkenones, such as high melting points (~60°C), renders the direct product unsuitable for use as a diesel fuel, but nonetheless represents an important and as yet unexplored renewable carbon feedstock.