913 



of the proper factors. These factors have been worked out by distill- 

 ing chemically pure aiabinose and xylose with hydrochloric acid and 

 determining the amouut of furfurol yielded. Eoughly speaking, these 

 pentaglucoses yield nearly half of their weight in furfurol. A large 

 number of determinations of the pentaglucoses in different agricultural 

 products have been made under the author's direction. The results of 

 some of these determinations are given in the following table and are 

 compared with the average percentage of nitrogen-free extract in these 

 materials, the figures for which are taken from Mentzel and v. Len- 

 gerke's Landw. Kalender for 1891. 



Pentaglucoses and nitrogen-free extract in feeding stuffs, etc. 



Pentaglu- 

 coses. 



Kitrogen- 

 free ex- 

 tract. 



Rre straw 



Wheat straw 



Barley straw 



Oat straw 



Pea vines 



Meadow liay 



Clover hay, first period 



Clover bay, second period . . . 



Beech woorl 



Spruce wood 



Brewers' grains 



Wheat bran 



Sugar beet diffusion residues 



Beet pulp 



Crude fiber from oat straw. . . 



Per cent 



25. 

 25. 8, 27. 



25. 

 25. 8, 26. 



16. 



18. 



9. 



10. 

 23.8,19. 

 13.2, 7. 



22. 



24. 



33. 



24. 



13. 



Per cent. 

 33.3 

 36.9 

 36.7 

 36.2 

 34.0 

 41.4 



\ 35.0-38.0 



43.6 

 .55.6 

 54.8 



It will be seen that in many cases, as in the straw of cereals, the 

 pentaglucoses amount to more than half of the nitrogen -free extract, 

 while in the case of pea vines, meadow hay, clover hay, diffusion chips, 

 and wood considerable amounts are ijresent. The crude fiber of oat 

 straw as determined by the Weende method is shown to contain a con- 

 siderable amount of pentaglucoses. The results indicate how impor- 

 tant a factor this class of bodies may be in fixing the nutritive value of 

 the nitrogen-free extract, provided they are found to j)ossess a higher 

 or a lower nutritive effect than starch or sugar.* 



It has been claimed by some chemists that furfurol occurs in the 

 d<'composition products of albuminoid bodies, and it was suggested that 

 by digesting albumen or casein with acid, pentaglucoses might be 

 formed. To test this matter experiments were made with casein and 

 with horse meat, both of which were carefully freed of all carbohy- 

 drates, which showed that only mere traces of furfurol were formed. 

 The conclusion is, therefore, that albuminoid bodies yield only traces of 

 furfurol. Glycuronic acid, however, numerous derivatives of which 

 occur in the urine of men and animals after consuming certain sub- 

 stances, was found to yield similar amounts of furfurol to arabinose and 

 xylose. * 



■ stone found the pentaglucoses to be less digestible for rabbits than the other 

 curbohydrates {Am. Chem. Jour., 14, No. 1). 

 2GG21— No. 12 6 



