Macroalgae brown algae

Iken K, Amsler CD, Hubbard JM, McClintock JB, Baker BJ (2007) Allocation patterns of phlorotannins in Antarctic brown algae. Phycologia 46 386-395 Iken K, Barrera-Oro ER, Quartino ML, Casaux RJ, Brey T (1997) Grazing in the Antarctic fish Notothenia coriiceps-. evidence for selective feeding on macroalgae. Antarctic Sci 9 386-391... 

The taxonomic diversity of freshwater macroalgae represents a counterpoint to the diversity of these groups in marine systems. Fewer than 3% of the 4,000 species of rhodophytes occupy freshwater habitats, and most occur in lotic, or flowing-water, systems (Sheath 2003). Similarly, only five of the seven species of freshwater brown algae (Phaeophyceae) have been recorded from North America (Wehr 2003). In contrast, more than 75% of the over 4,000 species of aquatic chlorophytes have been isolated from freshwater habitats, including many filamentous and colonial forms (Graham and Wilcox 2000). 

To date, no clear evidence of inducible defenses among freshwater macroalgae has been reported, in contrast to their marine algal counterparts. For example, certain species of marine brown algae increase phlorotannin production in response to damage by mesograzers (Amsler and Fairhead 2006 see Chaps. 3 and 7). Whether Chara and Cladophora, two species of freshwater chlorophytes with putative allelopathic activity, increase allelochemical concentration in response to competitors remains to be seen (see Sect. 5.7.3). 

Honkanen T, Jormalainen V, Hemmi A, Makinen A, Heikkila N (2002) Feeding and growth of the isopod Idotea baltica on the brown alga Fucus vesiculosus. roles of inter-population and within-plant variation in plant quality. Ecoscience 9 332-338 Eloyer K, Karsten U, Wiencke C (2002) Induction of sunscreen compounds in Antarctic macroalgae by different radiation conditions. Mar Biol 141 619-627 Ilvessalo H, Tuomi J (1989) Nutrient availability and accumulation of phenolic compounds in the brown algae Fucus vesiculosus. Mar Biol 101 115-119 Jones CG, Firn RD (1991) On the evolution of plant chemical diversity. Phil Trans R Soc Lond B, Biol Sci 333 273-280... 

Confirmation of the presence of four arsenosugars, a class of compounds found in other marine macroalgae (Francesconi and Edmonds, 1997), was reported in a study of the marine brown alga Fucus distichus (Harrington et at., 1997). 

For nonpolar secondary metabolites (e.g., metabolites with no known primary function in the organism s physiology) from macroalgae, only two other studies (besides those on D. pulchra) are known in which care has been taken to test metabolite concentrations at ecologically realistic levels. The first is the study of Schmitt et al.17 for terpenoid metabolites from the brown alga Dictyota... 

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