The key difference between linoleic acid and linolenic acid is that linoleic acid contains two double bonds with cis configuration while linolenic acid contains three double bonds with cis configuration.
Linoleic acid and linolenic acid are the two essential fatty acids we have to obtain from the diet because our body cannot synthesize them. Moreover, these fatty acids are essential for our health.
CONTENTS
1. Overview and Key Difference
2. What is Linoleic Acid
3. What is Linolenic Acid
4. Side by Side Comparison –Linoleic Acid vs Linolenic Acid in Tabular Form
5. Summary
What is Linoleic Acid?
Linoleic acid is an essential fatty acid having the chemical formula C18H32O2. It is a carboxylic acid and has an 18-carbon chain. The carbon chain has two double bonds with cis configuration. Therefore, we can denote it as 18:2 cis-9,12 in which 9 and 12 are the carbon atoms having the double bonds. Typically this compound occurs in nature as a triglyceride ester. Further, this compound is highly soluble in organic solvents such as acetone, benzene, ethanol, etc. The molar mass of this compound is 280.45 g/mol. It appears as a colourless oil.
Figure 01: Linoleic Acid
When considering the uses, there are industrial applications as well as applications in the research field. In industries, we can use linoleic acid to make quick-drying oils for oil paints and varnish, as a surfactant, as an ingredient in beauty products, etc. The most important dietary sources for linoleic acid include Salicornia oil, safflower oil, and melon seed oil.
What is Linolenic Acid?
Linoleic acid an essential fatty acid having the chemical formula C18H30O2. Its most common form is alpha-linolenic acid because it is the most stable and abundant form. Moreover, it is an essential fatty acid and thus, we need to take from our diet because our body cannot produce it.
Figure 02: Structure of Alpha-Linolenic Acid
Furthermore, this compound has an 18-carbon chain with 3 double bonds in the cis configuration. Therefore, we can denote it as 18:3 cis-9,12,15 in which 9, 12 and 15 are the carbon atoms having double bonds. Its molar mass is 278.43 g/mol. The important dietary sources of linolenic acid include kiwifruit seed, Chia, Perilla, Rapeseed, Soybean, etc.
What is the Difference Between Linoleic Acid and Linolenic Acid?
Linoleic acid is an essential fatty acid having the chemical formula C18H32O2 while linoleic acid an essential fatty acid having the chemical formula C18H30O2. However, the key difference between linoleic acid and linolenic acid is that linoleic acid contains two double bonds with cis configuration while linolenic acid contains three double bonds with cis configuration.
According to the configurations in these compounds, we can denote linoleic acid as 18:2 cis-9,12 and linolenic acid as 18:3 cis-9,12,15. When considering the dietary sources, the most important dietary sources for linoleic acid include Salicornia oil, safflower oil, melon seed oil, etc. The important dietary sources of linolenic acid include kiwifruit seed, Chia, Perilla, Rapeseed, Soybean, etc.
Summary – Linoleic Acid vs Linolenic Acid
Linoleic acid is an essential fatty acid having the chemical formula C18H32O2 while linoleic acid an essential fatty acid having the chemical formula C18H30O2. The key difference between linoleic acid and linolenic acid is that linoleic acid contains two double bonds with cis configuration while linolenic acid contains three double bonds with cis configuration.
Reference:
1. “Alpha-Linolenic Acid.” Wikipedia, Wikimedia Foundation, 1 July 2019, Available here.
Image Courtesy:
1. “LAnumbering” By Edgar181 at English Wikipedia – Transferred from en.wikipedia to Commons (Public Domain) via Commons Wikimedia
2. “ALAnumbering” By en:User:Edgar181 – en:Image:ALAnumbering.png, re-drawn in BKchem+perl+inkscape+vim, (Public Domain) via Commons Wikimedia