THE EFFECT OF ENVIRONMENTAL FACTORS ON THE GROWTH OF A HALOPHYLIC SPECIES OF ALGAE

¹ Department of Physical and Biological Sciences, Southwest Research Institute, San Antonio, Texas 78228
² Department of Biology, University of Utah, Salt Lake City, Utah 84112

A halophylic species of Dunaliella was isolated from the Great Salt Lake, Utah, and established in axenic culture. A balanced culture media was developed containing major and minor elements as well as a sufficient concentration of an osmotic agent. The effects of various environmental factors on the growth of this species of algae were investigated and optimum growing conditions were delineated. Optimum conditions for growth of this species are as follows: (1) temperature 32° C; (2) NaCl 19.2% (w/v); (3) CO₂ 1-2% at a rate of 2.2 ml/min/ml of culture media; (4) light intensity 25-35 Klux; and (5) pH 5.8-6.5. The K⁺ Na⁺ ratio should not be more than one, and better growth took place when this ratio was less than 0.1. The specific growth constant for this halophyte under the above conditions was 0.069 hrs^-1, which is equal to a doubling time of 10.0 hours.