Gelidium species

I. Gomez, F.L. Figueroa (1998). Effects of solar UV stress on chlorophyll fluorescence kinetics of intertidal macroalgae from southern Spain a case study in Gelidium species. J. Appl Phycol, 10, 285-294. 

Agar. This gum is extracted from certain marine algae belonging to the class Rhodophyceae, red seaweed, which abound off the coasts of Japan, Mexico, Portugal, and Denmark. Important species include Gelidium cartilagineum and Gracilaria confervoides. 

Agar is obtained by freeze-drying a mucilage derived from Gelidium amansii Lamouroux, other species of the same family (Gelidiaceae), or other red algae (Rhodophyta). 

Finally, the impact of UV-B radiation on marine macrophytes has been mostly conducted on individual species and not on the whole community. The criteria to select species for experimentation/analyses have varied (a) they are key species due to their contribution to primary production, or because they create a habitat for other marine plants and invertebrates, as the seagrass Posidonia oceanica in the Mediterranean Sea [42,122], Laminaria beds in the North Sea [123], or Macrocystis on the Pacific coast of California [4], (b) they represent a high share of macroalgal biomass in the ecosystem, as Ulva in eutrophic coastal waters [124] and, (c) they are commercially important as Porphyra sp., Gelidium sequipedale, Macrocystis pyrifera or Chondrus crispus [30,38,125,126]. 

Hernandez, I., Fernandez, J.A. and Niell, F.X. (1995) A comparative study of alkaline phosphatase activity of two species of Gelidium (Gelidiales, Rhodophyta). European Journal of Phycology 30, 69-77. 

Juanes, J. A. and Borja, A. (1991). Biological criteria for the exploitation of the commercially important species of gelidium in Spain. Hydrobiologia 221, 45-54. 

The Gehdiales are very well known and studied for the production of agars, but studies on their secondary metabolites are rare. A polyhalogenated monoterpene, gehdene, has been isolated from the species Gelidium sesquipedale, harvested in Morocco. This molecule has one of the typical carbon skeletons of the genus Plocamium (Aazizi, Assef, and Faure, 1989). 

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