The Sequestration of Oxy-Polybrominated Diphenyl Ethers in the Nudibranchs Miamira magnifica and Miamira miamirana.

A series of oxy-polybrominated diphenyl ethers (O-PBDEs) has been isolated from the extracts of Miamira magnifica and Miamira miamirana collected from Queensland, Australia. M. magnifica sequesters the new OH-PBDE 1 and six known OH-PBDEs containing four to six bromines (2-7). M. miamirana also accumulates known tribromo- and tetrabromo OMe-PBDEs 8-10 in both mantle and viscera tissues. To date, Miamira is the only genus of the family Chromodorididae that is known to incorporate O-PBDEs, rather than terpenes, in the mantle where the metabolites may play a putative role in chemical defense. The extract of M. magnifica was tested in a brine shrimp lethality assay and exhibited an LD50 of 58 μg/mL.