AGRICULTURAL. CHEMISTRY — ^AGROTECHNY. 803 



phatids, and cerebrosids, and the second part with the biochemistry of these 

 bodies. 



Lipase produced by microbes, N. L. Sohngen {E. Akad. Wetensch. Amster- 

 dam, Proc. Sect. 8ci., 13 {1911), pt. 2, pp. 1200-1210, pi. 1, fig. 1).—It was found 

 that tlie composition of the medium was of no consequence as far as the secre- 

 tion of iipase by various lipolytic micro-organisms was concerned. Therefore, 

 every source of carbon and nitrogen which can be utilized will serve as a 

 producer of lipase. Acids secreted by microbes will, however, diminish the 

 secretion of lipase. Hydroxyl ions accelerate the activity of the lipases, while 

 hydrogen ions check it. 



" Calcium and magnesium ions favor the action of lipase ; likewise trime- 

 thylamin and sodiumglycocholate ; monovalent alcohols counteract the process, 

 sugars and glycerin exerting no influence. Presence of oxygen and light favor 

 the decomposition of fat by the action of liptsse. By means of microbic lipase 

 fat may be synthetically obtained. From oleic acid and glycerin chiefly the 

 monoglycerid results, but besides, probably a little di- and tri-glycerid. Microbic 

 lipase shows great similarity to liver and pancreatic lipase." 



In regard to the physiolog'y of plant catalase, B. Preobraschen'sky {Trudy 

 Imp. 8. Pcterh. Obshch. Estcstvo. {Trav. Soc. Imp. Nat. St. Petersh.), IjO 

 {1909), I, No. I, pp. 276-287; ahs. in ZentU. Allg. u. Expt. Biol., 2 {1911), No. 

 5-6, p. 121). — Substances such as acid sodium and potassium phosphates, which 

 stimulate alcoholic fermentation, also increase the catalytic power, while those 

 which inhibit alcoholic fermentation also inhibit catalytic activity. Catalase is 

 therefore active in anaerobic processes. The work was conducted with zymin 

 and wheat seedlings. 



Note on a peptid-splitting' enzym in woman's milk, L. M. Warfield {Jour. 

 Med. Research, 25 {1911), No. 1, pp. 235-237).— Human milk was found to con- 

 tain a ferment capable of splitting the dipeptid glycyltryptophan. This enzym 

 was quickly destroyed by acidity, but an amount of formaldehyde capable of 

 inhibiting bacterial growth, or pasteurizing at a temperature of 60° C, will 

 not destroy it. 



The separation of rennin and pepsin by the passage of a direct electric 

 current, W. E. Burge {Am,er. Jour. Physiol, 29 {1912), No. 3, pp. 330-33/,, 

 fig. i).^The results indicate that in a solution containing both rennin and pepsin 

 the passage of a direct electric current of 10 milliamperes for 25 hours will de- 

 stroy all the peptic power, while the rennetic action is apparently unchanged. 



Effect of ignition on solubility of soil phosphates, G. S. Fraps {Jour. 

 Indus, and Engin. Chem., S {1911), No. 5, p. 335). — It is a well-known fact that 

 the ignition of soil samples will increase the amount of phosphates soluble in 

 an acid solution. This author has, therefore, investigated Stewart's method 

 (E. S. R., 23, p. 423) for estimating the organic phosphorus in the soil. 



He found that " ignition increases about 10 times the solubility of the phos- 

 phoric acid of wavellite, dufrenite, and variscite in fifth-normal nitric acid. 

 Ignition renders variscite, dufrenite, and wavellite almost completely soluble in 

 12 per cent hydrochloric acid. Ignition of the soil will probably render inor- 

 ganic phosphates soluble in acid, and therefore is not a method for estimating 

 organic phosphoric acid. Ignition of the soil also renders considerable quanti- 

 ties of iron and aluminum oxids soluble in acid." 



The determination of nitrogen in commercial ammoniates of high nitrogen 

 content, C. H. Jones et al. {Jour. Indus, and Engin. Chem., 3 {1911), No. .9, 

 pp. 691-699). — This is the first report of the committee on nitrogen of the divi- 

 sion of fertilizer chemists of the American Chemical Society. It gives the re- 

 sults for moisture by the vacuum and usual methods, and for nitrogen by the 

 Kjeldahl with permanganate, Kjeldahl without permanganate, Kjeldahl-Gun- 



