Bromoperoxidase activity and vanadium level of the brown alga Ascophyllum nodosum.

Abstract Vanadium-dependent peroxidase activity in extracts of Ascophyllum nodosum growing in the intertidal region close to Roscoff/France, and algal vanadium levels, followed approximately similar seasonal variation, as deduced from a study lasting from April 2005 to March 2006. High peroxidase (PO) activity was found in extracts obtained from algae collected in between midwinter to spring [∼100–190 U per g dry mass (dm), triiodide assay] with a maximum in April. Periods of reduced PO activity lasted from summer to early winter (∼50–90 U per g dm). High vanadium levels (1.5–2.2 mg kg −1  dm) were found in algae collected from midwinter to spring, whereas reduced levels (0.6–1.4 mg kg −1  dm) were found in summer to early winter.