Fractionation macroalgae

These estimates include a Gt C contributbn from macroalgae. The ef ratios are a measure of the fraction... 

FIGURE 6.1 Organic mercury fraction (%) in three macroalgae species along a mercury gradient in a temperate estuary. (After Coelho et al. 2005. Estuar. Coast. Shelf Sci. 65 492-500. With permission.)... 

The peroxides that activate these enzymes are produced internally by th biota or, alternatively, are produced externally, mainly by photochemical proc esses in the sea (72). Gschwend et al. (71), having found very little halocarboi in the interior tissues of macroalgae that produce these compounds, conclude" that much of the activity must be located in the surface tissues. This findin is consistent with the idea that extracellular peroxides are involved in th activation of these haloperoxidases. Moffett and Zafiriou (73) and Cooper am Zepp (74) provided evidence that peroxidases associated with aquatic particle in fresh water and coastal waters account for a large fraction of the decay o hydrogen peroxide, although it was not shown that haloperoxidases were re sponsible for the observed activity. 

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