Phlorotannin herbivore interactions

The Importance of Herbivore Gut Characteristics in Phlorotannin-Herbivore Interactions... 

Very little information exists on the phenolic protein-conplexing resins, except for that on creosote bush and sane arctic plants. In contrast to condensed tannins and hydrolyzable tannins, these are typically ether-soluble compounds this may allow their entry into the body across cell membranes, and thios give them the potential for action outside the gut lumen. Reports for animals consuming seaweed indicate that astringent protein-precipitating substances (presumably phlorotannins), are potentially important in marine plant-herbivore interactions. 

Although most work on the effect of secondary metabolites on digestive processes has occurred in the phlorotannin-herbivore system, thousands of other nonphlorotannin metabolites have been identified as putative deterrents.1 Studies of some of these have shown that the metabolites can have negative post-ingestive consequences.190191 And, although little work has been done on these secondary metabolites with respect to consumer digestion processes per se, the complexity of the interactions is apparent from studies that suggest that the effectiveness of the chemical defense is linked to prey nutritional quality,36 37 calcification,37 192-195 and recent prey/consumer history.32... 

Suzuki Y, Takabayashi T, Kawaguchi T, Matsunaga K (1998) Isolation of an allelopathic substance from the crustose coralline algae, Lithophyllum spp., and its effect on the brown alga, Laminaria religiosa Miyabe (Phaeophyta). J Exp Mar Biol Ecol 225 69-77 Svensson CJ, Pavia H, Toth G (2007) Do plant density, nutrient availability, and herbivore grazing interact to affect phlorotannin plasticity in the brown seaweed Ascophyllwn nodosum. Mar Biol (in press), doi 10.1007/s00227-007-0649-5 Swanson AK, Druehl LD (2002) Induction, exudation and the UV protective role of kelp phloro-tannins. Aquat Bot 73 241-253... 

Svensson CJ, Pavia H, Toth GB (2007) Do plant density, nutrient availability, and herbivore grazing interact to affect phlorotannin plasticity in the brown seaweed Ascophyllum nodosum Mar Biol 151 2177-2181... 

Terpenes and phlorotannins are two structural classes of secondary metabolites that are particularly important in mediating chemical interactions between marine plants and herbivores. Terpenes are commonly found in tropical macroalgae such as members of the Dictyotales (Phaeophyta) and... 

It is difficult to know if the results of the in vitro and ex vivo studies to date can be accurately extrapolated to in vivo systems.70 124 However, the work clearly demonstrates the subtlety and complexity of the interactions. In addition, it suggests that there is agreement between the phlorotannin-protein complexation that is observed at acid pH in vitro and the low assimilation efficiencies of phlorotannin-rich food observed in most acid gut species.25,34 120 121 124 An exception appears in herbivores where there is the strong likelihood that other factors mitigate or alter the effect of the acid environment on phlorotannin-protein complexes.25,35 49 56 124... 

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