424 



Miss J. White. The Ferments and 



[Mar. 3, 



the two specimens used being the same ; but as material which had entirely 

 lost its power of germination was not obtainable, the results in this case are 

 not perhaps quite so convincing as in the case of the other cereals. 



It might be urged that since the resting seeds were not stored in an 

 absolutely dry condition, the persistence of the diastase might be due to its 

 being reproduced as fast as it decomposed, but a comparison of the South 

 Australian results with those from Victoria and New South Wales does not 

 give any evidence of this. 



2. Proteolytic Enzymes. — The first method adopted for the demonstration 

 of these ferments was approximately the same as had been employed by 

 Prof. Vines in his paper on " The Proteases of Plants,"* the difference being 

 that in this case from none of the seeds had the integuments been removed 

 before grinding. 



The grain, 10 grammes in each case, was crushed by the hand mill, and put 

 into 100 c.c. of distilled water and shaken for two hours. The material was 

 then filtered and the filtrate was used as the digestive solution without 

 precipitation of the enzymes. 



Into bottles containing 50 c.c. of this solution were put 3 drops of hydro- 

 cyanic acid and 0'2 gramme of well-washed fibrin which had been carefully 

 preserved in spirit. Into a similar bottle were put 50 c.c. of the same 

 solution which was thoroughly boiled, and when cold - 2 gramme of washed 

 fibrin and 3 drops of HCN were added to this bottle also. These bottles 

 were put into the oven at a temperature of 36 c C. As in the case of 

 diastase, control experiments in which commercial pepsin was employed 

 were rendered impossible owing to the constant presence of traces of 

 peptone mixed up with the pepsin, which was obtained both in the form of 

 & powder, and as scales, but always containing the same impurities. 

 Attempts to separate the pepsin and peptone by fractional dialysis failed. 



After about 20 hours in the oven, application of the biuret test showed 

 the presence of slight traces of peptone in the unboiled specimens, whilst 

 the boiled specimens when similarly tested only gave the violet colour 

 characteristic of undigested proteids. 



On treating some of the aqueous solution from the seeds in exactly the 

 same way as the above, with the single exception that no fibrin was added 

 to the bottle, application of the biuret test showed the presence of minute 

 quantities of peptone, thus indicating the occurrence of autolysis. The 

 results obtained in this way are tabulated along with those obtained when 

 dealing with solutions prepared by another method to be now described. 

 In order to diminish autolysis and to obtain more satisfactory results, the 

 * 'Annals of Botany,' vol. 20, 1906, p. 115. 



