230 CAROTENOIDS CONTAINING CARBONYL GROUPS XII 



1934-36 Karrer and co-workers^' carry out a detailed investigation of the 



new pigment and establish its constitution. 

 1938 KuHN and Sorensen^^ show that the eggs of the lobster do not contain 



esterified astacene ("ovoester"), but a new pigment, astaxanthin. They 



establish the constitution of astaxanthin and its close relationship to 



astacene. 



Occurrence 



It was originally assumed that astacene and astaxanthin are typical animal 

 pigments. More recent investigations show, however, that these pigments are 

 also present in plant organisms^^. 



Since the isolation of astacene from lobster (shell, hypodermis and eggs^^), 

 numerous other sources of this carotenoid and of astaxanthin have been found. 

 The pigment occurs either esterified or combined with protein. The protein 

 adduct appears to be ionic in nature, with the protein as the positively charged 

 component (cf. p. 235). 



TABLE 48 



OCCURRENCE OF ASTAXANTHIN OR ASTACENE* ^^ 



Source References 



I. Green algae 



Haematococciis plnvialis+ R. Kuhn, J. Stene and N. A. Sorensen, Ber. y2 



(1939) 1688. — J. TiscHER, Z. physiol. Chcm. 250 

 (1937) 147. 



II. Protozoa: 



Euglena heliorubescens'^ J. Tischer, Z. physiol. Chem. 23g (1936) 257; 267 



(1941) 281. 



III. Spongiaria: 



Axinella crista-galli P. Karrer and U. Soimssen, Helv. chim. Acta 18 



(1935) 915. 



IV. Crustacea : 



a) Malacostraca: 



1) Schizopoda Euphausia J. C. Drummond and R. McWalter, /. exper. Biol. 12 



(1934) 105. 



2) Decapoda:' 

 Astacus gamniarus'^ , Shell, 



hypodermis, eggs R. Kuhn and N. A. Sorensen, Ber. yi (1938) 1879. 



Cancer pagurus ■ R. Fabre and E. Lederer, Bttll. Sac. Ch-ini. Biol. 16 



(1934) 105. 



Sources from which astaxanthin was isolated are marked"*". In other cases it is not 

 known for certain whether astacene is the natural pigment or a transformation product of 

 astaxanthin. 



References p. 253—255. 



