1918.] AGRIOULTUKAL CHEMISTRY — AGROTECHNY. 503 



Whether this effect is due to a progressive destruction of the ferment or to a 

 particular inliibiting action of the glycerin has not yet been determined. 



Toxic and antagonistic effects of salts on wine yeast (Saccharomyces 

 ellipsoideus), S. K. Mitra {Univ. Cal. Pubs. Agr. Set., S {19111), No. 5, pp. 63- 

 102, figs. IJf). — In the investigations reported the toxic effects of single salts 

 and the antagonistic effects of combinations of salts on the growth of yeast 

 were studied. The yeast S. ellipsoideus was selected on account of its universal 

 use in wine making. The salts tested were the chlorids of potassium, magne- 

 sium, calcium, and sodium, selected because their metallic ions are those most 

 abundant in the ash of grape juice. The nutrient solution was prepared from 

 hydrolyzed cane sugar, phosphoric acid, and ammonia. To 100 cc. of the solu- 

 tion was added the salt or combination of salts under investigation in various 

 strengths of molecular concentration from 0.001 to 2.2M. After inoculation 

 Rith 1 cc. of a pure culture of the yeast, the flasks were kept in an incubator 

 at 28° C. The activity of the yeast was determined by the multiplication of 

 cells noted at intervals of 48 hours for a period of 12 days. 



The toxic effects of the single salts were as follows: (1) Each of the four 

 single salts is more or less toxic to the yeast. At a certain concentration potas- 

 sium chlorid is the least toxic and sodium chlorid the most. (2) The lower 

 concentrations of each salt stimulate, the higher concentrations inhibit, the 

 growth of yeast. The optimum concentrations for growth were found at 0.2M 

 KCl, O.IM MgCU, O.OIIM CaCU, and O.OOIM NaCl. The lowest concentrations at 

 which growth was inhibited were at 2.2M KCl, 1.2M MgClz, 0.7M CaCh, and 

 0.2M NaCl. (3) The results are quite different from those found by other in- 

 vestigators with either bacteria, the higher plants, or animals, yeast standing 

 midway between plants and animals. (4) Toxicity is also shown by a decrease 

 in the size of the yeast cell with higher concentrations of the salts. 



The antagonistic effects of combinations of the dilTorent salts in pairs were 

 found to be in the following order from highest to lowest : MgCU v. CaCU, 

 KCl V. CaCU, MgCl2 v. NaCl, KCl v. NaCl, KCl v. MgCl^, and CaCU v. NaCl. 

 Expressed in terms of valency of ions, it was found that divalent ions may 

 antagonize monovalent and divalent ions, and that monovalent ions may an- 

 tagonize divalent ions and to a slight extent monovalent ions. In general the 

 antagonistic elTect on yeast was found to be similar to the recorded work on 

 bacteria, plants, and animals. 



The experimental data are given in tabular and graphical form and a bib- 

 liography of 38 references to the literature cited is appended. 



A study of the water-soluble accessory growth-promoting substance in 

 yeast, I, J. C. Drummond {Biochem. Jour., 11 {1911), Nos. 3-Jf, pp. 255-272, figs. 

 15). — The literature on the properties of the " antineuritic vitamin" and the 

 growth-promoting food accessory " Avater-soluble B " is reviewed, and investi- 

 gations aiming at the isolation and identification of the latter substance are 

 described. Experimental evidence is given demonstrating that certain of the 

 properties possessed by both are very similar, thus supporting the view of Mc- 

 Collum and others that the two substances are identical. Attempts at isolating 

 the water-soluble accessory in yeast were unsuccessful, but the failure was 

 attributed by the author more to the adsorption of substances of this class 

 from solution by precipitates than to their reputed instability. 



Contributions to the biochemistry of pathogenic anaerobes. — II, The acid 

 production of Bacillus welchii (B. perfringens) and B. sporogenes (Metch- 

 niffok), C. G. L. Wolf and S. V. Telfer {Biochem.' Jour., 11 {1917), No. 3-4, 

 pp. 197-212, figs. 2). — This continues work previously noted (E. S. R., 38, 

 p. 483). 



