1909] SCH REINER & REED— OXIDIZING POWER OF ROOTS 377 



When a few drops of alcoholic guaiac are added to water, or a 

 suitable solution of salts, in which wheat seedlings have grown for 

 sveral days, there is sometimes a faint blue color, indicating the 



more 



When a 

 drop of hydrogen peroxid is added, however, the liquid turns blue, 

 giving a color varying from medium to very intense, depending 

 somewhat upon the age of the seedlings, and the number of roots 

 which have grown in the culture. The guaiac-peroxid reaction 

 indicating a peroxidase is confirmed by the reaction to phenolphthalin 

 and aloin, both of which agree in showing the presence of peroxidase. 

 When the roots of a young wheat plant are immersed in an alcoholic 

 guaiac solution, they immediately turn blue, indicating that they are 

 relatively rich in oxidase, although but little oxidase appears in the 

 water in which they grew. This may be due to the retention of 

 oxidase by the root cells during life, but when the outer cells are killed 

 by the alcoholic guaiac the oxidase escapes and becomes evident 

 trough its reaction with guaiac. An aqueous extract of crushed 

 roots, shows strong oxidase reaction as well as peroxidase reaction. 

 In the course of a brief examination of different parts of the young 

 wheat plants, it was found that the partially depleted seeds showed 

 a very strong oxidase reaction when guaiac was used, while the per- 

 oxidase reaction was relatively less than in the extract of crushed 

 roots. 



When the solution in which wheat roots have been grown for 

 ^e days is boiled for five or ten minutes, and cooled, the oxidase 

 a nd peroxidase reactions disappear. 

 - The temperature at which the peroxidase is destroyed was deter- 

 I mined by heating a culture liquid which showed an active peroxidase 

 ac tion. The culture liquid was heated to successively higher tempera- 

 ^es and held at each for five minute periods. The temperature at 

 *hich the enzymes appeared to be destroyed was 6o° C. or very close 

 hereto. 



The culture liquid was examined for enzymes in a series of cu - 

 ^es of different ages to learn whether the enzyme reaction was equally 

 str <*g in all. Wheat seeds were germinated on perforated cork 

 P la tes floating on the surface of water in crystallizing dishes ot 500 

 ^Pacity. When cultures were on hand aged two, three, four, nve, 



