12-20-34(4)23-16-27-37(7)29-30-39-38(8)28-17-31-40(39,9)10/h11-12,14-16, 18-20,22-30,39H,13,17,21,31H2,1-10H3/b12-11+,22-14+,23-16+,26-15+, δ-Carotene (delta-carotene) or ε,ψ-carotene is a form of carotene with an ε-ring at one end, and the other uncyclized, labelled ψ (psi).
It is an intermediate synthesis product in some photosynthetic plants between lycopene and α-carotene (β,ε-carotene) or ε-carotene (ε,ε-carotene).
[1] δ-Carotene is fat soluble.
Delta-carotene contains an alpha-ionone instead of a beta-ionone ring;[2] this conversion is carried out by the gene Del which shifts the position of the double bond in the ring structure.
The formation delta-carotene under the presence of the Del gene is sensitive to high temperatures.