1920] AflRICULTURAT. CHEMISTRY AGROTECHNY. 203 



creased, less alkali is required, and less formate produced. Neutral barium 

 and strontium salts are less effective as condensing catalytic apents. 



" The best method is by running 7 to 8 cc. of 3.5 per cent sodium hydrate into 

 li.'tO cc. of O.S per cent calcium formate containing 5 cc. of 40 per cent formalde- 

 hyde while boiling in a condensing tlask. The reaction is completed in a few 

 minutes, and as soon as a pale yellowish tinge appears all the formaldehyde 

 has disapp(>ared. 



"The sugar nnxture is optically inactive, and contains reducing pentoses and 

 reducing fermentable hexoses. Carbon dioxid and water are readily polymerized 

 , to sugar by tiie aid of magnesium. The production of calcium tartrate [pre- 

 viously noted] during sugar .synthesis has not been confirmed, and was po.ssibly 

 due to the use of an oxidized sample of formaldehyde." 



The inversion of cane sugar during the storage of oranges, G. Andr6 

 (Compt. Rend. Acad. Sci. \I'arix]. 110 {l<)2n). Nn.^. 2, pp. 12G-12S; 5, pp. 292- 

 295). — A study is reported of the changes taking place in the sugar content of 

 oranges during storage in an aseptic medium. 



Sections of a ripe orange were placed in a closed receptacle containing a 

 few drops of toluene to prevent the development of molds. After four months 

 these sections were analyzed for acidity calculated as citric acid, reducing 

 sugars, and sucrose, and the analyses compared with similar ones made on 

 other sections from the .same fruit analyzed at the beginning of the period of 

 storage. The results of these analyses showed that, while the content of citric 

 acid had not changed appreciably, the sucrose had been converted to a con- 

 siderable extent into reducing sugars. This hydroly.sis is considered to have 

 been caused by the presence of citric acid rather than of a sucrose. 



Analyses of solutions of sucrose and citric acid in concentration approximat- 

 ing that of orange juice and kept for varying periods of time indicated that 

 I lie hydrolysis of the sucrose is mucli slower in the orange in its natural state 

 than in the synthetic solution. This is explained on the ground that in the 

 tissues of the orange the mixture of sugars and citric acid is not homogeneous, 

 tli(» two materials being located in different cells across which the exchange 

 of liquids is very slow. A further proof of this was furnished by experiments 

 iu which orange juice was analyzed in a similar manner, the inversion of sugar 

 taking place much more rapidly than in the whole orange. 



A series of analyses of orange juice heated and unheated, In the natural 

 state, and neutralized, showed that the formation of invert sugar was not 

 affected by heating or neutralizing the juice. In juice kept in a closed recep- 

 tacle the inversion of the sucrose was less rapid than in juice exposed to the 

 oir. 



The utilization of -methylglucosid by Aspergillus niger, A. W. Dox and 

 <;. W. RoARK, .IK. {Jonr. Biol. Chan., 41 (1920), No. 4, pp. 47 5-Jf 81). —The authors 

 report a study of the extent to which A. nificr can utilize a -methylglucosid. 

 which had previously been found by Dox and Neidig (E. S. R., 30, p. 11) to be a 

 less favorable medium than the beta form for the growth of the fungus. 



The results of the present study indicate that while A. niger grows very 

 Iioorly on media containing a -methylglucosid as the only .source of carbon, it 

 grows readily on sucrose "Tned la in the presence of the glucosid. "A vigorous 

 culture transferred entire to the glucosid medium without sucrose may use up 

 the glucosid more rapidly than a culture obtained by direct inoculation of this 

 medium with spores. If the original medium contained both sucrose and 

 glucosid the latter disappears more rapidly from the second medium containing 

 glucosid but no sucrose than when the original medium contained sucrose alone. 

 Also, there was a slight difference between the activity of cultures before and 

 after spore formation. 



II 



