Commercial Microbial Oils

In this review, we aim to provide details of microbial oils that have been considered of commercial potential and to describe in more detail those microbial systems that are in commercial operation to provide key fatty acids for the expanding... 

As already discussed, the cost of SCO manufacture is high because of the high capital costs involved in the construction of large fermenters and associated machinery as well as in the costs of operation. If a microbial oil is to be exploited commercially, then the SCO must command a premium price (32, 33). In reahty, this means that microbial sources for oils can only be a commercial reality if the SCO produced is (1) destined for human consumption and (2) not readily available from traditional sources, either plant or animal. 

TABLE 4. Fatty Acid Profiles of Microbial Oils Rich in Arachidonic Acid and Docosahexaenoic Acid that are Produced Commercially (from 55). 

We are extremely grateful to Professor Sakayu Shimizu, Kyoto University, Japan, for providing information about the current commercialization of microbial oils in Japan. We are also indebted to Dr. David Kyle, Advanced BioNutrition Corp., MD, for his perceptive reading of this manuscript and for his shrewd comments. 

Ratledge, C. (1992) Microbial Lipids commercial realities or academic curiosities, in Industrial Applications of Single Cell Oils, eds. D.J. Kyle and C. Ratledge, American Oil Chemists Society, Champaign, IL, pp. 1-15. 

All organic chemicals are, by definition, based on chemicals derived from living matter. Thus, the ten highest-volume commercial organic chemicals are all made from starting materials obtained from petroleum (oil) and natural gas, which are believed to have been formed by the microbial decomposition of ancient marine plants and animals. 

Energy Biosystems Corporation has developed a biocatalytic pilot plant that removes sulfur from crude oil. The biocatalyst is based on a soil bacterium isolated for its ability to selectively desulfurize fossil fuels. The relevant genes from these bacteria have been isolated and are being manipulated and transferred to alternative microbial hosts to increase expression of the desired properties. This leads to increased efficiency of the process. Currently, this technology is being optimized for eventual commercialization for the petroleum industry. 

Several other procedures have been developed to protect unsaturated fatty acids from ruminal biohydrogenation. Of these, only the amide derivative has extensive research documentation (Jenkins, 1998, 1999), but has not been applied commercially. Often, calcium soaps of palm oil or canola fatty acids are referred to as protected. These are not protected from ruminal biohydrogenation (Table 2.2), but rather are ruminally inert with regard to their effects on the rumen microbial population. 

Safari, M., Kermasha, S. 1994. Interesterification of butterfat by commercial microbial lipases in a cosurfactant-free microemulsion system. J. Am. Oil Chem. Soc. 71, 969-973. 

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