Lipolytic Activities. 



77 



During the past year, a number of experiments were carried 

 out on the lipolytic actions of duodenal contents of human beings, 

 both after fasting and after taking food. The Einhorn or the 

 Palefski tube was used to collect the secretions. The behavior 

 was tested, with toluol as antiseptic, toward ethyl butyrate and 

 triacetin under various conditions. The results obtained may 

 be divided into two groups. Greater action toward ethyl butyrate 

 than toward triacetin was observed when no food had been taken 

 for at least twelve hours and the pancreatic juice therefore prob- 

 ably absent. Very much greater action toward triacetin than 

 toward ethyl butyrate was observed in the cases in which food 

 had been taken and the pancreatic juice was present. These 

 relations were observed in a number of cases, but in several cases 

 exceptional results were obtained. Under apparently normal con- 

 ditions of digestion, when the activity should have been that of the 

 pancreatic juice, that is, very large toward triacetin, a greater 

 action toward ethyl butyrate was observed. Also, when pan- 

 creatic juice was expected to be absent, the activity observed in 

 several cases was similar to that observed when it was present. 

 Since, however, relatively few of these cases were observed, the 

 greater activity toward triacetin of duodenal contents containing 

 pancreatic juice, and the greater activity toward ethyl butyrate 

 of contents without pancreatic juice, may for the present therefore 

 be looked upon as the normal. 



From the diagnostic point of view, these results indicate that 

 the lipolytic activity, and perhaps also the activities of the other 

 enzymes of duodenal contents, may sometimes be caused by secre- 

 tions other than the pancreatic juice, even if the conditions for 

 obtaining the latter are apparently favorable. 



Since vegetable substances offer a more constant and satis- 

 factory material for an extended experimental investigation, the 

 lipase of the castor bean is being studied from various points of 

 view. Two active preparations have been obtained from castor 

 beans, which correspond to the two lipases just spoken of. One of 

 these is more active toward ethyl butyrate than toward triacetin, 

 the other more active toward triacetin than toward ethyl butyrate. 

 In brief, the former may be obtained by extracting oil- and husk- 

 free castor beans with water and precipitating with ammonium 



