ABSTRACTS OF REPORTS OF FOREIGN INVESTICrATIONS. 



The chemical distinction between true albuminoids, albumose, 

 and peptone, M. Flaum {Clum. Zf<j., 15 (J^.vi), n-i).. p. x-A'/.s). — Tlie 

 author explains tliat throu<ili the studies of Kiihne, Chittenden, and 

 Neumeister that part of the science of clieinistry peitaininji- to the albu- 

 minoid bodies lias reached a uew ])hase. The albunioses and peptones 

 are products of the true albunnnoi<ls, and are formed both in the course 

 of the pepsin-pancreas digestion and by the action of <libited acids. 

 The first product is acid albumin, which by long- con tinned digestion 

 goes over to albumose. The albumoses change by further action of 

 enzymes ov «liluted acids into the ditfercnt ix'ptones. 



Among the reagents for reeognizing albuminoid materials are several 

 which permit of discrimination between albumen, albumose, and pep- 

 tone. Tlie eharacteristic precipitates obtained with nitric acid, acetic 

 acid and common salt, and acetic acid and ])otassium ferrocyanidc 

 do not disappear on heating if they are caused by true albuminoids: if 

 caused by albumose the precijiitatc is dissolved by heating and reajt- 

 pears on cooling. The peptones give no ])recipitate with those reagents. 

 The biuret reaction is a commonly used reaction, but it shows the red 

 color in the i)resence of peptones. For the juirpose of distinguishing 

 between and separating albumose and ]»ept<uie, ammonium suli>hate is 

 re<'ommended, which precipitates all albumose but leaves the i>ei»tones 

 in solution. The reagent in form of a fine powder is added to the 

 solution to be treated to the i>oint of saturation. The comiilete pre- 

 cii)itation of albumose recpiircs about L'4 hours. Peptone, according to 

 Kiihne, possesses no nutritive value. The animal (ugauism can not use 

 it to supply the requisite amount of albuminoids in the bo<ly. Albu 

 mosc. on tlu^ contrary, is com|>lctely regenerated to albumiiKu'ds. au<l 

 can nourish the organism as wi'll as tiue albuminoids. It is therefore 

 in reality not the peptone l»ut tin' albumose that is wanted in the 

 so-called peptone jtreparations (ttfered for sale. 



The application of the centrifuge in analytical and microscopic 

 work, W. Thbrner (r//fwj. Zt(j., ir, {]S!)i). pp. J 201-JM-^).— The autluu- 

 nu'iitions the use of the centrifuge in milk analyses tor determining fat, 

 and claims that it is adai)table to analysis of Hour, ground feeding stutfs, 

 butter, etc. In his tests the autluu- used a Victoria centrifuge capable 

 of G,00() to T.OOtt revoluti«uis per minute. 

 488 



