Sea‐Nine™ 211 (4,5‐dichloro‐2‐(n‐octyl)‐3(2H)‐isothiazolone) is a Potent Stimulator of Eicosanoid Biosynthesis in the Sea Squirt, Ciona intestinalis (L.)

The isothiazolone, Sea‐Nine 211™, is a broad‐spectrum antifoulant whose mechanism of action is poorly understood. In the light of recent reports that eicosa‐noids may modulate invertebrate larval settlement, the present study examined the effect of Sea‐Nine 211 on eicosanoid biosynthesis in the sea squirt, Ciona intestinalis. Using RP‐HPLC and examination of peak absorption spectra, the tunic of this species was shown to produce a range of lipoxygenase products, including 8‐HEPE, 12‐HEPE, 8,15‐diHEPE and 8,15‐diHETE. Sea‐Nine 211™ was similar in potency to the calcium ionophore, A 23187, in inducing biosynthesis of these eicosanoids, being maximally effective at 5–10 μM. While the effect of Sea‐Nine 211 on C. intestinalis settlement has yet to be examined, it is suggested that this antifoulant may exert its action, at least in part, by modulating eicosanoid biosynthesis.

Key words:

• Sea‐Nine 211
• isothiazolone
• biocide
• antifouling
• eicosanoid
• tunicate
• Ciona intestinalis

Notes

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