Sustainable Production of Omega-3 Polyunsaturated Fatty Acids using Recombinant Cyanobacteria
This novel recombinant vector provides a sustainable source of omega-3 polyunsaturated fatty acids (PUFAs) for use in aquafeeds. The genetically manipulated cyanobacteria produce elevated levels of omega-3 polyunsaturated fatty acids (PUFAs) enriched with stearidonic acid and create a cost-effective, sustainable source of aquafeeds for fisheries worldwide.
Scientists at Wake Forest School of Medicine have developed a novel recombinant vector that causes a significant increase in stearidonic acid production when inserted into the genome of cyanobacteria. Traditionally, these cyanobacteria have relatively low oil content. Using the recombinant vector, researchers have increased the total lipid content in certain strains of cyanobacteria, creating a vast source of stearidonic acid for use as aquafeed.
Unlike transgenic plants, which require large-scale farming, cyanobacteria can be cultured at a commercially viable scale. Presently, stearidonic acid comprises only 16-23% of the total fatty acids in transgenic soybean plants. This novel technology increases the levels of stearidonic acid in cyanobacteria to more than 40% of total fatty acids. These features make this technology superior in the creation of a globally sustainable source of stearidonic acid-enriched aquafeeds that can be used to grow fisheries for the production of omega-3 products for human consumption.
Consumption of long chain omega-3 PUFAs is associated with numerous health benefits, including brain and eye tissue development, reduced risk of cardiovascular disease, decreased inflammation and management of depression. Demand for these products is growing rapidly, outpacing the global supply for fish oil and placing significant strain on commercial fisheries, the primary source of these fatty acids. As demand increases, prices for fish oil and meal rise, forcing aquaculturists to supplement aquafeed with cheaper plant-based omega-6 PUFAs. This causes a marked reduction in the long chain omega-3 PUFA content in fish flesh because the omega-6 PUFAs limit the biosynthesis of long chain omega-3 PUFAs in fish by competing with the its precursor, alpha-linolenic acid, for necessary enzymes. Consequently, the nutritional benefit of these fish for human consumers is decreased.
Stearidonic acid, an omega-3 PUFA that is a precursor of long chain omega-3 PUFAs, does not compete with omega-6 PUFAs in the biosynthesis pathway, making it an attractive candidate for aquafeed supplementation. It also converts to omega-3 long chain PUFAs more efficiently than alpha-linoleic acid. Despite these attributes, stearidonic acid sources, which are primarily plant-based, are difficult to produce commercially and have low stearidonic acid content.
The recombinant vector has been optimized, and lipids have been characterized. Cyanobacteria are being produced at the laboratory scale.
- Leslie B. Poole, PhD, Professor of Biochemistry
- Floyd H. Chilton, PhD, Professor of Nutritional Sciences at University of Arizona
- Derek Parsonage, PhD, Assistant Professor of Biochemistry
- Susan Sergeant, PhD, Assistant Professor of Biochemistry
U.S. Provisional Application on file 62/398,604