610 EXPERIMENT STATION EECORD. 



" There was fouud to be no close correspondence between the saccharifying 

 power of the different fractions and the iodin reaction of the saccharified 

 starch solutions obtained in determining this power. The authors conclude 

 that the quantitative value of the liquefying power of the amylases of grains is 

 Independent of their saccharifying power, that their starch-dextrinizing power 

 is to some extent independent of both of the former, and that they possess 

 also in varying degrees a starch-precipitating power due to amylo-coagulase." 



For previous work see an earlier note (E. S. R., 23, p. 410). 



The enzyms of Linaceae, J. V. Eyke (Chem. News, 106 {1912), No. 2758, pp. 

 167, 168; al}s. in Chem. Ztg., 37 {1913), No. 28, p. 281).— The results show that 

 quite a number of enzyms may be present in the leaves and seeds of this plant 

 and that the amount varies considerably. Linase acts less strongly upon lina- 

 marin than upon prunassin. During growth enzym activities toward lina- 

 marin become less and an increase In hydrolysis of prunassin and amygdalin 

 is noted. The enzymatic activity seems to stand in close relation with the 

 presence of cyanogenetic glucosids. The varieties of plants having blue, white, 

 or red flowers contain cyanogen while those of a yellow color have neither an 

 enzym nor a glucosid. 



The g'asometric determination of aliphatic amino nitrogen in minute 

 quantities, D. D. Van Slyke (Jour. Biol. Chem., 16 {1913), No. 1, pp. 121- 

 124). — The apparatus previously described (E. S. R., 29, p. 108) has been reduced 

 in size so that it may be used for small quantities of material, which brings 

 the procedure into the class of micromethods. With the microapparatus the 

 error need not be more than 0.005 mg. of nitrogen when 2 cc. or less of gas is 

 measured, or 0.01 mg. when more is obtained. 



Improved methods in the gasometric determination of free and conjugated 

 amino-acid nitrogen in the urine, D. D. Van Slyke (Jour. Biol. Chem., 16 

 (1913), No. 1, pp. 12o-13.'f). — "The previously published process of determining 

 the total amino-acid nitrogen (free amino acids + conjugated amino acids in 

 the form of hippuric acid, peptids, proteins, etc.)* has been simplified so that 

 the operation is much shortened and the more laborious parts, boiling off 

 ammonia and washing bulky precipitates, are disijensed with. The free 

 amino acids alone can readily be determined after decomposition of the urea 

 with soy-bean urease, which hydrolyzes urea completely without either freeing 

 conjugated amino acids or deaminiaing free ones. The applicability of the 

 gasometric method for the determination of hippuric acid is indicated." 



See also other notes (E. S. R., 25. p. 710; 26, p. 22). 



A method for the determination of small amounts of fat (preliminary 

 report), W. R. Bloob {Ahs. in Science, n. ser., 38 {1913), No. 98^, p. 678).— The 

 method consists of extracting the fat from tissues or liquids with an excess 

 of alcohol-ether (25 per cent of ether), putting an aliquot of the filtered ex- 

 tract into distilled water, and determining the amount of fat by comparing it 

 with a cloudy suspension of known fat content in a nephelometer. The method 

 has given good results with blood and milk. 



The analysis of maple products. — I, An electrical conductivity test for 

 purity of maple sirup, J. F. Snki.l (Jour. Indus, and Engin. Chem., 5 (1913), 

 No. 9, pp. H0-7II.7, figs. 2).— The method (E. S. R., 27, p. 207) is designed for 

 the detection of additions of sucrose to maple sirup. Inasmuch as sucrose 

 is a nonconductor of electricity and salt constituents conductors, a maple sirup 

 adulterated with sucrose will show a lower conductivity. The method is of 

 special value because the conductivity determination can be made in a few 

 minutes. 



Jour. Biol. Chem., 12 (1912 », No. 2, pp. 301-312. 



