Calendic acid

Calendic acid (sometimes α-Calendic acid) is an unsaturated fatty acid, named for the pot marigold (genus Calendula), from which it is obtained. It is chemically similar to the conjugated linoleic acids; laboratory work suggests it may have similar health benefits.

Biosynthesis
Calendic acid is an omega-6 fatty acid. though not usually listed with this group. Calendic acid (8t,10t,12c-18:3) is synthesised in Calendula officinalis from linoleate (9c,12c-18:2) by an unusual Δ12-oleate desaturase (a FAD 2 variant) that converts the cis-double bond in position 9 to a trans,trans-conjugated double bond system (8t,10t). An all-trans beta isomer has been described.

Uses
Calendula flowers have been used for many centuries. Ointments or extracts are applied medicinally for reducing inflammation, wound healing, and as an antiseptic.

Calendic acid is the fatty acid responsible for the reduction in feed intake and improved feed utilization in mice when calendular oil is added to the feedstuff, as demonstrated by the comparative experiments in the examples using corn oil.

In vitro, β-calendic acid shows anti-cancer activity against human colon cancer cells.