Tailored oils

摘要

Recombinant DNA techniques are used to produce oleaginous recombinant cells that produce triglyceride oils having desired fatty acid profiles and regiospecific or stereospecific profiles. Genes manipulated include those encoding stearoyl-ACP desturase, delta 12 fatty acid desaturase, acyl-ACP thioesterase, ketoacyl-ACP synthase, and lysophosphatidic acid acyltransferase. The oil produced can have enhanced oxidative or thermal stability, or can be useful as a frying oil, shortening, roll-in shortening, tempering fat, cocoa butter replacement, as a lubricant, or as a feedstock for various chemical processes. The fatty acid profile can be enriched in midchain profiles or the oil can be enriched in triglycerides of the saturated-unsaturated-saturated type.

主权项

1. A method comprising:
(a) providing a recombinant oleaginous microalgal cell of the class Trebouxiophyte, the cell comprising an exogenous delta-12 fatty acid desaturase gene under control of an amt03 promoter and an allelic disruption of an endogenous delta-12 fatty acid desaturase gene; (b) cultivating the cell under a first environmental condition wherein the exogenous delta-12 fatty acid desaturase gene is expressed, linoleic acid is produced and the cell divides, increasing the number of cells; (c) cultivating the cells under a second environmental condition of reduced pH relative to the first environmental condition wherein expression of the exogenous delta-12 fatty acid desaturase gene and consequently production of linoleic acid is reduced and oil accumulates in the cells; and (d) extracting the oil from the cells, wherein the oil is characterized by a polyunsaturated fatty acid profile with 5% linoleic acid or less.