﻿28 BOTANICAL GAZETTE [january 



inulase acts inside the fungal hyphae and is not secreted into 

 the surrounding medium. In this respect it resembles the 

 zymase and endotrypsin of yeast, and like them belongs to the 

 class of endo-enzymes. 



INFLUENCE OF THE REACTION ON THE ACTIVITY OF INULASE. 



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It seemed desirable to ascertain whether the inulase found 

 by Green in Helianthus tiiberosiis has the same properties as the 

 inulase of the fungi ; and whether or not the inulase of Asper- 

 gillus is identical with that of Penicillium. A thorough investi- 

 gation of all the properties of these enzyme preparations has 

 not been made. The most distinctive property given by Green 

 is that alkalies are harmful to the inulase of artichoke, and that 

 very dilute acids facilitate its action. To test the influence of 

 the reaction of the solution upon the activity of the inulase 

 of Aspergillus and Penicillium the following experiments were 

 undertaken. 



L An inulin solution was made with 1.7569^"" of inulin 

 dissolved in 155^^ of water containing a small amount of toluol. 

 Of this solution 75^*^ were placed in each of two flasks. To 

 flask A were added 30'''^ of a suspension of i^"" of Aspergillus 



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powder in 35"^^ of water; to B, 30^*^ of distilled water. Thir- 

 teen test-tubes were filled as follows: 



No. I. 10" from flask A^ ~\- 10" of 0.0002 normal H2SO4 



No. 2. lo"^^ from flask A + 10*^'' of 0.002 normal H2SO4 



No. 3. 10'^'' from flask A + lo^"" of 0.02 normal H2SO4 



No. 4. 10" from flasks + 10'^'' of o.i normal H 2 SO 4 



No. 5. 10^^ from flask A + 10" of distilled water 



No. 6. 10'='^ from flask A + ^^^"^ of distilled water and boiled 



No. 7. 10*^'' from flask A -f- to*^*^ of 0.0002 normal KOH 



No, 8. 10"^^ from flask A + 10'=*' of 0.002 normal KOH 



No. 9. 10^'' from flask ^ -\- lo"^"^ oi o,Q^ normal KOH 



No. 10. 10*^*^ from flask B ~\- lo'"'' of 0.0002 normal H2SO4 



No. II. 10^^ from flask B -|- lo"""^ of 0.002 normal H2SO4 



No. 12. lo*^"^ from flask B -\- lo""^ of 0.02 normal H2SO4 



No. 13. lo*^*^ from flask B + 10^^ of o.i normal H2SO4 



Each tube was corked and allowed to stand at 35-37° C. for 

 forty-five hours, at the expiration of which each was boiled and 

 allowed to cool. All were filtered, the first few cubic centi- 



* Before each 10^^ was removed, the flask was thoroughly shaken in order that 

 equal quantities of the suspended powder might be taken each time. 



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