Algae. 2002; 17(2): 89-93.
Relationship between Phycoerythrin and Nitrogen Content in Gloiopeltis furcata and Porphyra yezoensis
Hiroyuki Mizuta, Yasuhiro Shirakura, Hajime Yasui
Laboratory of Breeding Science, Graduate School of Fisheries Sciences, Hokkaido University
Seasonal changes of pigment composition in two intertidal red algae, Gloiopeltis furcata (Postels et Ruprecht) J. Agardh, and Porphyra yezoensis Ueda, were investigated. Chlorophyll a and phycoerythrin levels were high during winter, but decreased in late spring or summer, with accompanying discoloration from deep red to green or yellow. This discoloration corresponded closely to the fluctuation of phycoerythrin content. Nevertheless, photosynthesis capacity was maintained by the increasing water temperature in the field, suggesting that large amounts of phycoerythrin are not necessary for photosynthesis. Phycoerythrin content correlated significantly with nitrogen content in both species when the nitrogen level was greater than the level of critical content (1.30% DW in G. furcata, and 2.26% DW in P. yezoensis), indicating that phycoerythrin plays a more important role in the nitrogen status as a nitrogen pool than that of nitrogen critical content. Furthermore, the dependence level of the algae on phycoerythrin as a nitrogen pool was greater in P. yezoensis than in G. furcata because of the remarkable increase of phycoerythrin content in P. yezoensis with increasing nitrogen content.
Keywords : discoloration, Gloiopeltis furcata, nitrogen, phycoerythrin, pigment composition, Porphyra yezoensis, red algae