THE CULTURE OF ALGAE FOR PHYSIOLOGICAL 



RESEARCH ' 



JACK MYERS 



Department of Zoology and the Laboratory of Algal Physiology 

 University of Texas, Austin, Texas 



The culturing of algae for physiological studies has called 

 forth a number of different techniques developed according to 

 the objectives of the work. Most physiological work on the algae 

 has been done with unicellular Chlorophyta such as Chlorella, 

 Scenedesmus, and Stichococcus. My remarks therefore will be 

 concerned principally with the culturing of forms such as these. 



One common objective is to understand nutrition or metabo- 

 lism of an alga in terms of its growth. This constitutes the sim- 

 plest and most productive starting point for any physiological 

 work. Experimental design must afford illumination, provide a 

 carbon source (usually COo), maintain constant temperature, and 

 include a means of estimating growth. In some cases growth ex-^ 

 periments have utilized cotton-plugged flasks, but if CO2 is the 

 carbon source, such procedure is highly questionable. One very 

 likely may be studying the physical characteristics of the vessel 

 in determining CO2 diffusion rather than the characteristics of 

 the algae. Oesterlind (1949) has introduced a technique of pro- 

 viding carbon dioxide as bicarbonate in the media and using 

 vessels sealed with rubber stoppers. More common procedure 

 (e.g. Warburg, 1919; Pratt, 1940; Winokur, 1948) has been to 

 use flasks of a design essentially similar to that shown in Figure 

 I. A 250 cc. or 500 cc. Erlenmeyer is provided with inlet and 

 outlet tubes for aeration and a rubber cap which can be used to 

 cover the cotton plug after inoculation. A mixture of 5% CO2 



^ This paper is based, in part, on work performed under contract N8- 

 onr-78000 with the Office of Naval Research. 



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