Submitted to: Journal of the American Oil Chemists' Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/16/2020
Publication Date: 1/6/2021
Citation: Gaskin, E.L., Carrero-Colon, M., Hudson, K.A. 2021. Combination of the elevated stearic acid trait with other fatty acid traits in soybean. Journal of the American Oil Chemists' Society (2021). 98:221-226. https://doi.org/10.1002/aocs.12446.
Interpretive Summary: Soybean seed is a source of oils used in biofuels, industrial lubricants, and fats for human consumption. Stearic acid is a saturated fat found at relatively low levels in soybean oil, but is neutral in its influence on cholesterol levels in consumers. A high stearic soybean oil would be desirable to the oil industry for physical properties, such as an increased melting temperature, which would make a soybean oil suitable for baking applications without the use of hydrogenation. In this work we use conventional genetic techniques to explore how the elevated stearic acid trait can be combined with elevated oleic or reduced linolenic acid to make an improved soybean oil.
Technical Abstract: Stearic acid is one of the five major fatty acids produced in soybean. It is a fully saturated lipid and is known for neutral or positive effects on LDL cholesterol when consumed by humans. Unfortunately, stearic acid only accounts for about 4% of the total seed oil produced in commodity soybean. Previous work has shown that stearic acid can reach levels as high as 28% of the total oil fraction when SACPD-C, the gene responsible for most of the stearic acid variation in soybean seed, is knocked out in combination with other loci. In order to increase stearic acid content and create soybeans with improved utility based on fatty acid composition, we combined SACPD-C mutations with other mutations in the fatty acid biosynthetic pathway. When combined, double mutant progeny carrying mutant alleles of both SACPD-C and FAD2-1A do not have elevated levels of oleic acid accompanying an increase in stearic acid levels. However, sacpdc fad3 double mutants have statistically significantly elevated levels of stearic acid and statistically significantly lower linolenic acid.