RECENT WORK IN AGRICULTURAL SCIENCE 



AGRICULTURAL CHEMISTRY— AGROTECHNY. 



Preliminary notes on the carbohydrates of the Musci, T. G. Mason (Set. 

 Proc. Roy. Dublin Soc, n. ser., 15 (1916), No. 2, pp. 13-28, fig. i).— In the ex- 

 amination of Polytrichum commune., Thuidium tamariscinum, and Sphagnum 

 cytnbifoUum, the author found dextrose, levulose, and sucrose present, while 

 maltose was found to be dependent on the presence of starch. Invertase was 

 found to be widely distributed, while diastase and maltase were found in 

 P. commune alone. The detection of diastase and maltase was dependent on the 

 presence of appreciable quantities of starch. In P. commune and <S. cymbifolium 

 the hexoses appear to be the chief form in which the carbohydrates descend 

 the stem. In regard to the necessity of a high concentration of hexoses for the 

 synthesis of sucrose by the invertase, it is indicated that " though the experi- 

 ments quoted in this work exclude the possibility of a high concentration for 

 the whole leaf, yet they do not demonstrate the absence of a localized high 

 concentration." 



It Is concluded that " the factors that operate in bringing about the syn- ' 

 thesis of sucrose in the plant cell are still very obscure " and that it is improb- 

 able that invertase in aqeous solution possesses this property. 



The destruction of pentoses in the course of alcoholic fermentation, H. 

 Pellett {Compt. Rend. Acad. Sci. [Paris], 163 (1916), No. 11, pp. 274-276) .—In 

 a study of the composition of molasses the author found, contrary to the gen- 

 eral assumption, that arabinose and xylose were decomposed by yeast when 

 present in a mixture of fermentable sugars, the quantity destroyed depending 

 upon the amount of yeast, the temperature, and the length of fermentation. 



For destroying the easily fermentable sugars so that the pentoses may be de- 

 termined by copper with reduction, 50 gm. of ordinary pressed yeast in a solu- 

 tion containing 100 gm. molasses should be used. The fermentation is usually 

 complete in 24 hours without any decomposition of pentoses. 



Applying the method to molasses the author found the material to contain no 

 appreciable quantities of pentoses but a nonfermentable substance which is 

 indicated as probably being the material " glutose," described by earlier inves- 

 tigators. 



The mode of action of plant peroxidases, G. B. Reed (Bot. Gas., 62 (1916), 

 No. 3, pp. 233-238, figs. 2). — Experiments similar to those reported in a study 

 of the platinum reaction previously noted (E. S. R., 35, p. 713) have been 

 repeated, using horse-radish root extract and potato peroxidase. 



The experiments have shown that just as the platinum is recharged with 

 oxygen by hydrogen peroxid as soon as some of the oxygen has been removed 

 from the platinum by a reducing agent, so the horse-radish and potato peroxi- 

 dase is recharged by hydrogen peroxid under similar conditions. It is concluded 

 that " in oxidation processes catalyzed by peroxidases two reactions are in- 

 volved. The peroxidase combines with oxygen from the oxygenases (or from 

 hydrogen peroxid, or possibly from some other source, since it is capable of tak- 



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