Implications for the use of Mortierella fungi in the industrial production of essential fatty acids

Research has shown that essential fatty acids (EFAs) are integral to proper nutrition. It has been found that EFA deficiency causes a host of ailments in animals, including humans. In addition, research has also shown that EFAs can reverse, as well as prevent, some human disorders and diseases. Current sources of EFAs have relatively low EFA contents and the oil extraction process is fairly costly considering the yields. As a result, there has been a marked increase in research targeted at finding alternate sources of EFAs that have higher yields and that are relatively inexpensive to produce on an industrial scale. Recent research has focused on the use of various moulds as potential producers of EFAs. Species belonging to the fungal genus Mortierella have attracted notable attention within this research area due to their potential as lipid producers and the fact that a significant portion of the fungal lipid contains EFAs. Research has also shown that the relative amounts of these EFAs can vary dramatically both between and within Mortierella species. A number of factors have been found to affect both the fatty acid compositions and the percentage of lipid bodies found in these fungi, which imply that the lipid composition of these moulds can be manipulated in order to obtain the fatty acids of interest in potentially large percentages. However, the optimization of these variables has yet to be achieved and the task is complicated by the fact that different species demonstrate varying optimization conditions. Consequently, more research must be done with regards to the optimization of these variables for industrial EFA production. This review paper provides a general introduction to the production of lipids from alternative sources and focuses on the production of EFAs in fungi belonging to the Mortierella genus. (c) 2004 Elsevier Ltd. All rights reserved.