306 . EXPERIMENT STATION EECORD. 



sis an<T precipitation witli animoniuiu sulphate a solution was obtained which 

 was absolutely identical with the unlieated preparation, showing that the coagu- 

 lation power was only apparently destroyed by the digestion. 



It is further shown that the coagulation power of a purified enzym is in- 

 hibited to quite an extent by the hydroxyl ions in milk. Enzym digested with 

 0.2 per cent hydrochloric acid and heated (prepared according to Mett) was 

 even more sensitive in this regard. Determining the coagulation time at blood 

 heat (37° C), as recommended by Hammersten is not a true measure of this 

 capacity. No ground evidently exists for the supposition that both a proteo- 

 lytic and a coagulating enzym exist in gastric juice. 



Reversibility of enzym actions and the effect of external factors on 

 enzyms, F. G. Kohl {Bot. CcntbL, Beihefte, 23 (WOS), 1. AM., i)p. 64b-6IfO; 

 abs. in ZentM. Agr. Chem., 38 {1909), No. 10, p. 71S; Jour. Chcm. Soc. [London], 

 98 {19 10), No. 567, I, pp. 82, 83).— It is shown that yeast extracts with a high 

 inverting power, when acting on sucrose solutions of known concentration in 

 the absence of light and at different temperatures, produced dextrose and levu- 

 lose up to certain limits and then remained stationary, or brought about a re- 

 version. The time factor was always dependent on the temperature and the 

 concentration. In this work bacterial action was excluded with thymol or 

 chloroform. Asparagln (0.05 per cent) was found to accelerate the hydrolysis, 

 while diffused daylight retarded it. 



About cellase, G. Bertkand and M. Holdereb (Bui. Soc. Chim. France, 4- 

 ser., 7 (1910), No. 5, i)p. 177-18.',; a^s. in Chem. Ztg., 3'/ (1910). No. 22, p. 

 186). — The authors were able to find cellase in almonds, apricot kernels, barley 

 kernels, and AspergiUus nigcr. It was absent in horse serum, at least in appre- 

 ciable amounts, in fermenting yeasts, and in a glycerin extract of Russula 

 quclrtii. See also a jirevious note ( E. S. R.. 23, p. 8). 



Food chemistry for 1909, G. Fendlek (Ztschr. Angcio. Chem., 23 (1910), 

 No. 15, pp. 673-68.'/). — A retrospect of the advances made in food chemistry 

 during 1909. 



Comment on the rapid detection of food adulteration, F. Rqthiea (Com- 

 ment Dcpistcr Rapldcuient Ics Fraudes Aliment aires. Paris, 1910, pp. IV-\-2S6, 

 figs. 18). — A small handbook containing methods for food analysis, with a dis- 

 cussion of the most common adulterations to be considered when interpreting 

 results. 



Estimation of the purins in foods, G. Bessau and J. Schmid (Ther. 

 Monatsh., 2.} (1910), No. 3, pp. lUi-121; abs. in Pharm. ZentralhaUe, 51 

 (1910), No. I'l, p. 279). — Burian and Schur's method was employed. In this 

 the nucleo-proteids are hydrolyzed by boiling for several hours with dilute acid. 

 After precipitating the pi-oteins (and boiling the precipitate repeatedly to 

 remove any remaining bases) the bases are precipitated from the solution by 

 bisulphite-copper sulphate. The precii)itate containing the bases is then de- 

 comix)sed with hydrogen sulphid, and after concentrating and filtering the solu- 

 tion they are reprecipitated with the silver reagent. The purin nitrogen is 

 then estimated in this second precipitate. The amount of nitrogen found rep- 

 resents about one-third of the actual purins present. 



A table appended shows that the purins in the muscle of various animal 

 species vary very little, particularly when red and white meats are compared. 

 The flesh of certain types of fisli contains a high but varying purin content, 

 appearing to be higher the smaller the species. Certain plants, for instance 

 spinach, kohlrabi, and cereals, contain appreciable amounts of purin. 



A new constituent of food products, A. Backe (Conipt. Rend. Acad. Sci. 

 [Paris], 150 (1910), No. 9, pp. j//6i-5//3).— Continuing previous work (E. S. R., 



