Omega-3 fatty acids are a family of polyunsaturated fatty acids (PUFAs) characterized by the presence of a double bond at the omega−3 carbon atom. The simplest omega-3 fatty acid is α-linolenic acid (18:3n-3), which is synthesized from the omega-6 fatty acid linoleic acid (18:2n-6) by desaturation, catalysed by delta-15 desaturase.