710 EXPERIMENT STATION EECOKD. 



In his present work he reports a new instance of this Ivind. In this he frac- 

 tionated proteins a and /3 with alcohol (methyl or ethyl) or acetone. He con- 

 clndes that there are either 2 proteins present, 1 which can be transformed Into 

 the other, or that there is 1 present the nature of which is changed by irregular 

 precipitation. 



A method for the quantitative determination of aliphatic amino groups; 

 some applications of this in the chemistry of the proteins, urine, and 

 enzyms, D. D. A'an Slyke (Ber. Dent. Chem. GcselL, .'/S {1910), No 16, pp. 

 3170-3181, fig. 1). — This method has been previously described in detail (E. S 

 R., 23, p. 303). 



A method for quantitative determination of aliphatic amino groups, 

 D. D. Van Slyke {Jour. Biol. Chem., 9 {1911), No. 3-J,, pp. 185-20 Jf, fig. 1).— 

 A portion of this w^ork has been previously noted from another source (E. S. R., 

 23, p. 303). 



The additional uses of the method are as follows: "Measurement of the 

 velocity and extent of proteolysis, determination of the relative digestibility of 

 proteins, quantitative determination of proteolytic enzyms, determination of 

 the complexity and structure of peptids and proteolytic products," and for the 

 " characterization of proteins." 



Quantitative determination of prolin obtained by the ester method in pro- 

 tein hydrolysis; prolin content of casein, D. D. Van Sly'ke {Jour. Biol. Chem., 

 9 {1911), No. 3-'i, pp. 205-207). — The prolin content of proteins can be rapidly 

 nnd accurately ascertained by determining the total and amino nitrogen of the 

 alcohol-soluble mixture. It was noted that each of the amino esters, the esters 

 of which distil over with that of prolin, will give off all of its nitrogen when 

 treated with nitrous acid as described in the Van Slyke method (E. S. R., 

 23, p. 303). 



As a result of hydrolyzing 464 gm. of casein and esterfying according to the 

 Fischer method the prolin nitrogen obtained was 3.775 gm., which corresponded 

 to 31.1 gm. of prolin. 



The results of attempts to crystallize out the prolin as a copper salt are also 

 reported. 



The carbohydrates of white pepper, K. H. Boddeneb and B. Tollens {Jour. 

 Landw., 58 {1910), No. 3, pp. 229-231). — In order to investigate the substances 

 from which furfurol and methyl furfurol (pentosans and methyl pentosans) 

 originate, the authors conducted hydrolyzing tests with white pepper fi-om which 

 all substances soluble in alcohol (piperin, etc.) had been extracted. The sirup 

 which was obtained by hydrolyzing the pepper for 6 hours with 5 per cent 

 sulphuric acid and saturating the extract with calcium carbonate and purifying 

 with alcohol only yielded with phenylhydrazin a phenyl-glucosan having a 

 melting point of 203° C, and which originated from starch. Mannose-hydrazon 

 was not obtained. 



Attempts to remove the starch and its products with diastase and autoclaving 

 and subsequent fermentation with yeast yielded negative results. As all the 

 hydrolyzed solutions had an odor of furfurol, and the vapor from such solu- 

 tions reddened anilin acetate paper, the authors concluded that the pentoses 

 were more or less decomposed by the preliminary treathient of the pepper. 

 In order to determine this, they hydrolyzed and fermented another sample 

 and examined the various intermediate products quantitatively for pentosans 

 and methyl pentosans, with the following results : The extracted pepper before 

 hydrolysis contained 2.21 per cent of pentosans and 1.73 per cent of methyl 

 pentosans. The residue from the pepper after hydrolysis contained 0.29 per 

 cent of pentosans and 0.05 per cent of methyl pentosans, the solution after 

 hydrolysis, 1.79 per cent of pentosans and 1.05 per cent of methyl pentosans, 

 the hydrolyzed solution after fermentation 1.04 per cent of pentosans and 0.33 



