HUMAN CHYLE. 159 



Ordinary chyle-fat 66'2 

 Butter chyle-fat 38*0 

 Purified butter-fat 31 '0 



Their Reichert-Meissl values were also determined : 



Ordinary chyle-fat 1'9 

 Butter chyle-fat 3'0 

 Purified butter-fat 27'5 



From these results we see that as far as the higher fats, e.g. olein, are 

 concerned the chyle comes to resemble very closely the composition of 

 the butter-fat taken in the food. Very different, however, is the 

 behaviour of the lower fats. Quite an insignificant amount of volatile 

 fatty acids appear in the chyle as compared with the quantity present in 

 the butter ingested. We see then that although the lower fats appear 

 to be absorbed and to pass into the chyle they disappear there with 

 surprising rapidity. Cohnstein and Michaelis (7) have shown that 

 blood exercises a lipolytic action on fats causing them to disappear with 

 the production of substances insoluble in ether but soluble in alcohol. 

 The nature of these products is as yet doubtful. Mayer (22) has found 

 that the sodium salts even of the lower fatty acids exert a toxic effect 

 when injected into the blood stream, the toxicity increasing as we ascend 

 the series. Munk (25) has shown that sodium oleate when injected is 

 markedly toxic ; on the other hand oleic acid itself produces no ill 

 effects. In this connection, however, the nature of the products formed 

 need not detain us; that lipolysis is the mechanism by which the 

 disappearance of the fats is brought about seems to be established (20) 

 and, we can account for the rapid disappearance of the lower fats on the 

 assumption that lipolysis proceeds more rapidly and energetically in the 

 case of the lower than the higher esters of a series. Support is lent to 

 this view by the results obtained by Hanriot (12) in his investigations on 

 the synthetic action of lipase. He found that in the case of the higher 

 fatty acids the formation of esters took place more easily and to 

 a greater extent than in the case of the lower members of the series and, 

 conversely, the lower members underwent hydrolysis more easily and 

 more completely than did the higher members of the series or, in other 

 words, equilibrium is attained in the case of the higher members of a 

 series only when relatively large quantities of ester are present and in 

 the case of the lower members only when the amount of ester present is 

 sufficiently small. The small amount of lower fatty esters in human fat 

 really represents the equilibrium point conditioned and maintained by 

 the supply of lower fatty acids in the food. In this connection the 



