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Ingvar Jorgensen and Walter Stiles. 
Finally the ether solution is concentrated by evaporation and 
the concentrated solution put in a dish in a vacuum desiccator. 
On complete removal of the ether, the chlorophyll a is left as a 
blue black mass. 
(9) Purification of Xanthophyll. To the extract containing 
xanthophyll obtainedas described in section 5,4 to5 litres of etherare 
added and a quantity of water. Any chlorophyll b that may he present 
is removed by saponifying it to chlorophyllin by shaking with 30 to 
50 c.c. of methyl-alcoholic potassium hydrate. The chlorophyllin 
is removed by repeated washing with water. 
The ether solution of xanthophyll is dried with sodium sulphate, 
evaporated to 30 c.c., and 200 to 300 c.c. methyl alcohol added. 
Complete removal of the ether is effected by evaporating down 
further and filtering the hot solution. On cooling, xanthophyll is 
deposited in the form of crystals forming shining plates. Water 
may be added to make the separation of the xanthophyll complete. 
The yield of xanthophyll from 2 kilos of dried nettle leaves is 0 8 
gram. 
(10) Purification of Carotin. The carotin is easily obtained. 
The extract containing it, obtained as indicated in section 5, is 
evaporated in vacuo at 40 n C., and the oily residue treated with 
300 c.c. of 90% alcohol. The carotin begins to separate out 
immediately in shiny steel blue crystals. Crystallisation is complete 
on standing in the cold. 
Any colourless impurity present in the crystalline mass is 
dissolved in petrol ether. 200 to 300 c.c. of this are therefore added 
and the carotin filtered from it. The purification is completed by 
treatment with a mixture of two parts of petrol ether to one part 
alcohol. The result is a yield of 0-25 gram of carotin from 2 kilos 
of dried nettles. 
(To be continued). 
