Delta 12 fatty acids

$$\sum UFA[\Delta 12]$$

Abbreviations

• ${\Delta }^{12}$

• $\Delta 12$

Description

Represents unsaturated fatty acids that contain a double bond at the 12th carbon from the carboxyl end. The most prominent and abundant example in nature is linoleic acid ($C18:2[\Delta 9,12]$), which is also the primary omega -6 fatty acid.

Nutritional potential:

Mammals, including humans, lack the $\Delta 12$-desaturase enzyme required to insert a double bond at this specific position. As a result, delta 12 fatty acids like linoleic acid are strictly essential and must be obtained through the diet (primarily from plant oils). They are critical for maintaining cell membrane fluidity, skin barrier function, and serving as precursors for biologically active signaling molecules (eicosanoids).

Biodiesel potential:

Because delta 12 fatty acids in nature are almost exclusively polyunsaturated (typically dienes or trienes, as the delta 12 bond usually follows a delta 9 bond), their presence in biodiesel feedstocks presents a trade-off. They significantly improve cold flow properties by lowering the cold filter plugging point (CFPP). However, their multiple double bonds make the fuel highly susceptible to oxidation (poor oxidation stability, OS) and reduce the cetane number (CN), which negatively impacts ignition quality.

References

• Okuley et al., 1994
• Moser et al., 2010