PHOTOSYNTHESIS IN ALGAE: II. GREEN ALGAE WITH SPECIAL REFERENCE TO DUNALIELLA SPP. AND TETRASELMIS SPP.

Abstract

The photosynthetic fixation of14CO2was studied in 10 species of chlorophycean algae and in 9 isolates of prasinophycean algae of the genus Tetraselmis.Green seaweeds had photosynthetic rates of 2.2 to 4.4 mg CO2 × h−1 × g−1, accumulated starch, glucose, fructose, and sucrose, and excreted very little recent photosynthate.Dunaliella spp. were distinguished by a high level of organic excretion (to 29.2% of the14C fixed in 2 hours), the production of glycerol and hydrogen sulfide, and the absence of dimethyl-β-propiothetin.Tetraselmis spp. excreted relatively small amounts of photosynthate in 2 hours, and produced mannitol and dimethyl-β-propiothetin but not hydrogen sulfide.