1915] 



DAVIS ENZYME ACTION IN MARINE ALGAE 809 



not so split, however, seems evident, at least not through the 

 activity of demonstrable algal enzymes, and in the face of 

 the negative evidence obtained, we would consider them as by- 

 products of metabolism rather than as playing the role of 

 reserves. As such, they would not be so comparable to the 

 reserve carbohydrates of the date as they would be perhaps to 

 the mucilaginous constituents of various seeds, as those of 

 flax, mistletoe, etc. These latter adsorb water readily with 

 gelatinization, and as far as is known, never function as re- 

 serves but act in a purely mechanical way (Czapek, '13, 

 p. 705). 



LIPASES IN THE ALGAE 



The almost universal presence of fats in the marine algae 

 led to the question of their assimilation. Accordingly, experi- 

 ments were set up to determine the lipolytic activity upon 

 emulsions of neutral fats as well as upon certain esters of 

 the lower fatty acids. For the neutral fats olive oil was 

 chosen as a substrate, and two general methods were employed 

 in forming the emulsion. 



The first, an olive oil-casein emulsion was made up after a 

 method described by Bloor ( '14). Four grams of casein were 

 placed in a warm mortar on a water bath and water added 

 until the whole formed a paste of medium viscosity. A drop 

 of phenylphthalein was added, then N/1 NaOH poured in and 

 stirred with the casein until the latter had been dissolved, this 

 point being indicated by a permanent pink tinge of the mix- 

 ture. Eight cc. of olive oil were stirred into the hot solution 

 and then ground with a pestle until all the oil globules had 

 disappeared. At this point the mortar was removed from the 

 bath and the emulsion cooled. During the cooling it was 

 found necessary to stir the mixture occasionally. The thick, 

 creamy mass resulting was diluted up to the required concen- 

 tration by the careful addition of water. If this dilution is 

 too great, the oil globules tend to rise to the surface. 



The second method was also suggested by Doctor Bloor, 

 but, as far as is known, has not been described. Eight cc. of 

 olive oil were dissolved in the smallest amount of absolute 

 alcohol necessary. This solution was run through a hot fun- 



