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Oxydase in Wheat Grains. 



By Katherine Golden Bitting. 



In many seeds the embryo is provided with a store of reserve food 

 formed by the parent plant before the separation of the seed. In the dor- 

 mant seeds the enzymes are usually in minute quantities as they are not 

 needed, but when the food is needed during the germinative process, the 

 enzymes are more strongly developed, the embryo dveloping itself, and 

 also developing enzymes to provide food in suitable form. 



A series of experiments were conducted to determine the enzymes 

 present in dormant wheat seed, and its parts, and also in the germinated 

 seed. The material for the experiments was obtained from a flour mill, 

 and consisted of whole wheat flour, ordinary white flour, bran, shorts, 

 and the unground grain. 



Water extracts were made, GO grams of flour being used with 100 

 cubic centimeters of distilled water, with the whole flour, and the white 

 flour, 150 cubic centimeters of water with the shorts, and 240 cubic 

 centimeters of water with the bran. The amount of water was varied 

 in order to make them of as nearly as possible equal moisture, the shorts 

 and the bran requiring more than the others. The mixtures were allowed 

 to stand for 12 hours, and were then filtered. Powdered thymol was 

 used to prevent decomposition. Glycerine extracts were also made, but 

 were so much weaker in their action than the water extracts, that they 

 were abandoned. 



To determine the changes in enzymic action due to the germinative 

 process, wheat was germinated for different periods, the grain being 

 placed on moist paper under a bell jar, and kept at room temperature. 

 At the end of the given period the grain was pounded in a mortar, then 

 the enzymes were extracted for three days with water to which chloro- 

 form was added, after which the extracts were filtered. The periods of 

 germination were three, five, six, and ten days respectively. Fifty 

 grams of wheat grains were used in each case, and for the extraction 

 200 cubic centimeters of distilled water. 



