Stearidonic Acid (SDA) is an omega-3 fatty acid with 18 carbons and 4 double bonds, which is commonly notated as C18:4n-3 or simply 18:4n-3. SDA is found in several plants and many fish.
Genetically Engineered SDA Omega-3 Soybeans
With the increased awareness of the importance of omega-3 fatty acids, particularly EPA and DHA, in the diet, Monsanto created a genetically engineered SDA Omega-3 Soybean known as MON 87769. Plant foods, including soybeans, often contain omega-3s in the form of alpha linolenic acid (ALA). However, the optimal form of omega-3s are considered to be eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
According to Monsanto's petition to deregulate MON 87769:
- "Studies have shown that the conversion of ALA to the more desirable long chain PUFAs [poly unsaturated fatty acids], EPA and DHA, found in fatty fish and algae, is inefficient in humans. As a result, studies have shown that it can take 14-20 grams of ALA to convert to 1 gram EPA (James et al., 2003). SDA is an eighteen carbon fatty acid with four double bonds (18:4n-3) that is naturally found in fish and fish/algal oil products and some plants. SDA is the intermediate in the biochemical pathway between ALA and EPA and does not require the action of delta-6 desaturase for conversion to EPA. As a result, conversion of SDA to EPA is much more efficient."
Sources of Stearidonic Acid
Stearidonic acid is not commonly found in plants, but it is found in the following plants:
- Black Currant seeds, Ribes Nigrum: 2.5%-4.5% SDA
- Borage seed, Borago offinalis: 0.5% SDA
- Hemp seed, Cannabis sativa: Up to 2% SDA
- Plants in the genus Echium (in the Borage family) often contain SDA, in amounts exceeding 20% in some species
- Asperuco procumbens (Borage family): 11.75% SDA
- Buglossoides arvensis (Borage family): 14.08% SDA
- Primula spp.: 11-14% 
Articles and resources
Related SourceWatch articles
- Genetically Engineered SDA Omega 3 Soybeans
- MON 87769
- Genetically Modified Organisms
- GMO Policies by Country
- Using Hunger to Promote Genetic Engineering
- Clarifications and Corrections to Petition #09-183-01p for the Determination of Non-regulated Status for MON 87769, Monsanto, February 4, 2010, p.374.
- Del Castillo ML, Dobson G, Brennan R, Gordon S, "Fatty acid content and juice characteristics in black currant (Ribes nigrum L.) genotypes.," Journal of Agricultural and Food Chemistry, 2004 Feb 25;52(4):948-52.
- J.L. Guil-Guerrero, F.F. García Maroto, and A. Giménez Giménez, "[http://lib3.dss.go.th/fulltext/Journal/J.AOCS/J.AOCS/2001/no.7/2001v78n7p677-684.pdf Fatty Acid Profiles from Forty-nine Plant Species That Are Potential New Sources of γ-Linolenic Acid]," JAOCS, Vol. 78, no. 7 (2001).
- J.C. Callaway, T. Tennilä, and D.W. Pate, "Occurrence of "omega-3" stearidonic acid (cis-6,9,12,15-octadecatetraenoic acid) in hemp (Cannabis sativa L.) seed," Journal of the International Hemp Association 3(2): 61-63.
- M. Berti, B.L. Johnson, S. Dash, S. Fischer, R. Wilckens, and F. Hevia, "Echium: A Source of Stearidonic Acid Adapted to the Northern Great Plains in the US," 2007. J. Janick and A. Whipkey (eds.). ASHS Press, Alexandria, VA.
- Stearidonic acid (18:4 omega 3) in Primula florindae, Accessed April 22, 2013.
- Clarifications and Corrections to Petition #09-183-01p for the Determination of Non-regulated Status for MON 87769, Monsanto, February 4, 2010.