CHLOROPHYLL 321 



By acting in moist 33 per cent acetone solution in the 

 absence of alcohol, ordinary hydrolysis was effected with the 

 formation of the monomethyl esters of the two chlorophyllins, 

 namely chlorophyllide a and h — 



/COOCH3 /COOCH 



y^CO ^COOH 



NH 



which may be separated by means of ether and petrol ether. 



The formation of crystalline methyl chlorophyllide is 

 readily demonstrated by placing i gram of fresh leaf of 

 Heracleum spondylium in a test tube with 4 c.c. of 75 per cent 

 methyl alcohol for three to four hours ; at the end of this time 

 yellow spots will have formed in the lamina due to the re- 

 moval of chlorophyll ; if held up to the hght the yellow spots 

 will show a number of black specks which under a microscope 

 are found to consist of deep green, almost black, pyramidal 

 crystals. 



Chlorophyllase belongs to the same class of enzymes as 

 lipase ; the latter substance, however, is only able to hydrolyse 

 amorphous chlorophyll, replacing the phytoxyl group by 

 hydroxyl ; it cannot effect alcoholysis. 



Chlorophyll appears to be always accompanied by the 

 enzyme, the amount increasing with the amount of chlorophyll. 

 In Mellitis Melissophyllum, Galeopsis tetrahit, Stachys silvatica, 

 Lamium maculatum, and Heracleum the amount of enzyme is 

 comparatively large. 



The activity of chlorophyllase may be demonstrated by 

 placing broken-up leaves of Heracleum or Galeopsis in 70 per 

 cent acetone (i gm. in 3 c.c). After a quarter of an hour 

 the acetone solution of the pigment is diluted with water and 

 extracted with ether ; on shaking the extract with 0-05 per 

 cent caustic soda the latter turns green owing to solution of 

 the sodium salt of chlorophyllide. Leaves previously boiled 

 to destroy the enzyme yield no colour to the caustic soda. 



The enzyme is also able to effect the synthesis of phytyl 

 chlorophyllide (amorphous chlorophyll) from chlorophyllide 

 and phytol. 



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