The yellow pathways indicate metabolites which are exclusively formed from symbiotic gut bacteria, as described by Kishino et al. [61]. The orange pathway is the ‘Jasmonate pathway', a pathway present in plants that leads to the biosynthesis of the major class of phytohormones, the jasmonates. This pathway was historically considered the only biologically relevant pathway of octadecanoids and was named the ‘Octadecanoid pathway' and is, therefore, shown in this figure for historical context.