11(r) hepe

11(R)-HEPE is produced by the oxidation of EPA by 11(R)-LO. This enzymatic activity and the resulting 11(R)-hydroxy acid have been isolated from the sea urchin S. purpuratus.

(±)8-HEPE is produced by non-enzymatic oxidation of EPA. It contains equal amounts of 8(S)-HEPE and 8(R)-HEPE. The ability of (±)8-HEPE to induce hatching of E. modestus and B. balanoides eggs is probably due to the presence of the 8(R) isomer within the racemic mixture.[1][2] Reference：[1]. Shing, T.K.M., Gibson, K.H., Wiley, J.R., et al. First total synthesis of a barnacle hatching factor 8(R)-hydroxy-eicosa-5(Z),9(E),11(Z)-pentaenoic acid. Tetrahedron Letters 35, 1067-1070 (1994).[2]. Hill, E.M., and Holland, D.L. Identification and egg hatching activity of monohydroxy fatty acid eicosanoids in the barnacle Balanus balanoides. Proceedings of the Royal Society of London Series B.Biological Sciences 247, 41-46 (1991).