- 72 - 



as the wash liquid as has been described before o Attempts to isolate 

 chlorophyll d in quantity usually lead to contamination of the product 

 by the isomers, which are formed in detectable quantities before the 

 pigment can be isolated o 



Chromatograp hic Sequence of the Chlorophylls and Their Isomers 



As a guide for the separation and identification of the chloro- 

 phylls, the sequence of the chlorophyll pigments in a coliunn of powdered 

 sugar is shown in Figure III,LL|.o This sequence was established by ad- 

 sorption of the pigments from petroleum ether solutions followed by de- 

 velopment with petrole\im ether containing 0.5 per cent n-propanolo The 

 chlorophyll c was isolated from brown algae, chlorophylls a^ and b from 

 leaves, and chlorophyll d from red algae„ The isomers were isolated 

 after heating n-propanol solutions of a, b and d. The protochlorophyll 

 was isolated from the inner seed coats of manroot, Cucurbitaceae (Ap- 

 pendix l)o It did not yield additional pigments when its solution in 

 propanol was heated. 



Isolation of the Methyl and Ethyl Chlorophyllides 



The methyl chlorophyllides were formed when chopped, fresh leaves 

 of mallow (Malvaceae) were treated with twice their weight of methanol 

 and allowed to stand for 6 to 2l\. hours-^-'-* 5. The pigments were then ex- 

 tracted and separated in columns of powdered sugar. Some free chloro- 

 phyllides were usually formed, and these were strongly sorbed at the 

 top of the colimm. The methyl chlorophyllide b was sorbed above the 

 chlorophyll b between neoxanthin and violaxanthino The methyl chloro- 

 phyllide a was sorbed above the chlorophyll a in the lutein plus 

 zeaxanthin zone as shown in Figure IIIjl5o 



