Agricultural and Biological Chemistry 



Effect of Excess Amino Acids on Growth of Certain Lactobacilli 



The effect on growth of lactic acid l)acteria from individual excesses of 

 15 amino acids was studied. The organisms employed were L. arahinosus, 

 L. jeniiciiti. L. casci, and L. Icicliuiannii. Growth repression of some of the 

 organisms was caused hy an excess of aspartic acid, glutamic acid, arginine. 

 valine, methionine, serine, or histidine. None of these compounds repressed 

 the growth of all organisms tested. It is concluded that the growth repres- 

 sions were due to toxicity of the individual amino acids concerned and 

 not to amino acid imbalance. 



A. E. Teeri 



Soluble Substances in Grass and Legume Silage 



Studies so far have shown little difference in the nature of these simple 

 nitrogen compounds" present in forages and in the silages made from them. 

 The total amounts of these nitrogen compounds in silage is far greater than 

 in the fresh forage. 



T. G. Phillips 



Studies Concerning the Determination of Ascorbic Acid in Food 



The tomato fruit is a good source of vitamin C. Plant i^reeders have 

 spent much time and effort in further improving the nutritive value of the 

 tomato. Dr. A. F. Yeager of the University of Xew Hampshire's Horti- 

 cultural Department has produced a new tomato variety known as Double- 

 rich which has considerably more vitamin C than the standard varieties. 



Previous studies in this laboratory have shown the presence of an 

 enzyme system capable of destroying vitamin C in chopped, sliced, or ma- 

 cerated tomatoes. If the tomatoes are heated, the enzyme is inactivated 

 and no longer able to destroy the vitamin C. 



In 21 samples tested, the anti-vitamin enzyme was found in large 

 amounts as follows : in one of the plant introduction varieties used for 

 breeding, two varieties with immature fruits, and in one hybrid with mature 

 fruits. The tests indicate that the anti-vitamin enzyme is carried along to 

 the progency in certain crosses more than others. 



S. R. Shimer 



Lasting Effect of Minor Elements and the Effect of 

 Sulfur and Lime Applications on the Yield of Oats 



I.ime had a depressing effect on the uptake of added cobalt and man- 

 ganese in both clover and grasses. Applications of cobalt effectively in- 

 creased the content of the forage ; applications of zinc gave slight increases ; 

 manganese, copper, and iron showed little effect. The clovers contained a 

 higher mineral content than the grasses, and the leafy portions of the 

 clovers contained the most. 



Greenhouse work with oats, using Paxton, Melrose. Charlton, and 

 Buxtcn soils, showed that the 600-pound application of sulfur gave yields 



