Survey of the C20 and C22 oxylipin family in marine diatoms

Abstract

Diatoms are highly abundant microalgae that are prolific sources for bioactive oxylipins, which are generated by the oxidative transformation of polyunsaturated fatty acids and contribute to the chemical defense of algae. We introduce herein a targeted survey of oxylipins from four diatom species with a focus on metabolites that also occur in mammalians. Analytical data from LC–MS/MS measurements indicate that diatoms produce a surprising variety of oxylipins, including several hydroxylated and dihydroxylated C18-, C20-, and C22-polyunsaturated fatty acids. It was also found that diatoms represent the first non-mammalian source for the resolvins (Rv)E2 and RvE3, which have recently been identified as modulators of inflammation in humans and rodents. The oxylipins are produced in response to mechanical disruption of the cells, suggesting their potential involvement in the wound-activated chemical defense of these diatoms.