INULIN FEEDING. 407 



of the liver after six days fasting 0.9 per cent of glycogen, the 

 equivalent of 0.329 gram of glycogen, or 0.252 gram per kilo 

 of body weight. In nineteen experiments with inulin-feeding 

 as outlined, the glycogen-content of the liver was increased in 

 the majority of cases; in six animals, however, negative 

 results were obtained. Of the thirty-six experiments by six 

 different investigators on inulin-feeding and glycogen-forma- 

 tion, which we have found recorded in physiological literature, 

 nineteen have given negative results. The experiments of 

 Miura are the most careful and satisfactory of all in point of 

 technique. He concludes his research with the following 

 remarks: "Renewed investigation is demanded to determine 

 whether the levulose found (post-mortem) in the various por- 

 tions of the intestine owes its formation to the action of one 

 or more of the digestive juices, to the acid of the stomach, or 

 to vegetable enzymes derived from the food ingested. In 

 view of the marked increase hi the glycogen-content of the 

 liver which follows levulose feeding, the conclusion is inevi- 

 table that ingested inulin is either converted to levulose only 

 in part, or too slowly to permit any storing up of glycogen 

 from the quantities of sugar absorbed. Herein, perhaps, lies 

 the explanation of the inconstancy of the experimental 

 results." * 



Regarding the behavior of inulin towards amylolytic 

 enzymes, the experiments of Mr. A. B. Siviter f in this labora- 

 tory afford an answer. He found that the ordinary amylolytic 

 enzymes such as the ptyalin of saliva, the amylopsin of the 

 pancreatic extract, vegetable diastase and " Taka " diastase 

 a very active enzyme preparation obtained from Eurotium 

 oryzge are without action on inulin. Dilute hydrochloric 

 acid (0.05-0.2 per cent) at 40 C. transforms inulin to 

 levulose. Hydrochloric acid combined with proteids likewise 

 inverts inulin to levulose, but more slowly than corresponding 



* Miura, Zeitschrift fur Biologic, 1895, xxxii, p. 265. 



t See Chittenden, Amer. Jour. Physiol. 1898, ii, p. xvii. Cf. also the re- 

 cent papers by Richaud, Comptes rendus de la socie'te' de biologie, 1900, lii, 

 p. 416. Bieri and Portier, ibid., 1900, lii, p. 423. 



