I9I5] Clarence J. West i59 



The lutein that separated was purified by repeated crystallization 

 from methyl alcohol (i gni. required looo cc. for Solution) or from 

 carbon disulfid. It formed dark, brownish-yellow, compact prisms 

 with blue surface-luster, melting at 195-6°. It differed from xan- 

 thophyll only in its higher melting point, and was called xanthophyll 

 b by Willstätter. 



Fucoxanthin. Fucoxanthin is the Carotinoid characteristic of 

 the Phaeophyceae, or brown algae. It differs from the other yellow 

 pigment, in its high oxygen content, having the formula, C40H54O6. 

 Many investigators^^ have had more or less pure Solutions of this 

 pigment, but Willstätter and Page^* were the first to obtain a crystal- 



line product. 



Fucoxanthin was isolated from the mother liquor of Chlorophyll 

 a (extracted with 85 percent acetone). Four liters of the extract 

 were treated with i 1. of a mixture of petroleum ether (30-5<>°» 

 3 vol.) and ether (i vol.) and then with 1.5 1. of water. The ether 

 mixture was then carefully washed free from acetone, concentrated 

 to about y2 1. and shaken with i 1. of methyl alcohol (saturated with 

 petroleum ether) four times, then twice with >4 1. of alcohol. The 

 xanthophyll was removed by shaking with an equal vol. of a mixture 

 of 5 vol. of petroleum ether and i vol. of ether. The fucoxanthin 

 was then transferred to a large vol. of ether, and the ether concen- 

 trated to a thick sirup. Fucoxanthin crystallized out upon the addi- 

 tion of low-boiling petroleum ether. The yield from 20 k. of 

 fresh algae was about 2 gm. of a product 85 percent pure. 



The use of all reagents containing mineral matter must be 

 avoided, if ash-free preparations are desired. It is also essen- 

 tial that all extracts and solutions be kept from the light and from 

 moisture as much as possible. If the algae are dried previous to the 

 extraction, the yield is very much smaller; and if this dry material is 

 kept for some time before being used, little if any fucoxanthin can be 

 isolated. 



The crude product may be recrystallized from methyl alcohol, 

 forming bluish, glistening, brownish-red, long, monoclinic prisms, 

 containing 3 molecules of alcohol. From methyl alcohol or acetone, 

 in the absence of air, it forms dark red six-sided tables containing 



33 Cf. Gaidukow: Ber. d. deutsch, bot. Gcsellsch., 21, 538, 1903. Tswett: 

 Ibid., 24, 234, 1906. Kylin : Ztschr. f. physiol. Chcm., 82, 221, 1912. 

 3* Willstätter and Page: Ann. d. Chem., 404, 237, I9i4- 



