CAROTENOIDS 



According to Wagner and Vermeulen ^ ^ the flesh, liver and milk of 

 blue and fin-backed whales contain no carotene and Morton and 

 Rosen '^^ could find no carotenoids in whale ovaries. 



As might be expected, the liver oil from the killer whale {Grampus 

 griseus) contains no carotenoids. ^ * 



Porpoise livers contain variable amounts of carotenes, but none was 

 ever found in embryos. ' ^ 



AMPHIBIA 



There is only one report of the presence of carotenoids in a marine 

 amphibian ; Lwoff ^ * reported carotenoids in the retina of an unidenti- 

 fied amphipod collected in a cove at St. Martin (Manche). 



CAROTENOIDS OF THE OCEAN BED 



It is not possible to leave a discussion of the carotenoids of the sea 

 without considering the important work of Fox and his collabora- 

 ^Qj-gST-sft Qji ii^Q carotenoids of the ocean floor. The carotenoids 

 which they examined in ocean mud are, biochemically speaking, of 

 great age. Their stability is due to the prevailing conditions : low 

 temperatures, absence of O2, and absence of light. The most striking 

 fact which emerges on examination of these carotenoids is that the 

 relative proportions of carotenes and xanthophylls are the inverse of 

 those generally found in marine flora and fauna ; whilst xanthophylls 

 predominate in living material carotenes predominate in the mud. 

 The amount of carotenes in marine living material varies (apart from 

 in some echinoderms) between and 35 per cent, of the total carotenoids 

 present ; in mud values fall between 35 and 83 per cent, p- Carotene is 

 the predominating mud carotene but smaller amounts of carotenes 

 characteristic of fungi, bacteria, ascidians, and sponges also occur in 

 small amounts. Mud xanthophylls are mainly those originally occurring 

 in algae, especially diatoms, but compounds very similar to antheraxan- 

 thin (see p. 50) and petaloxanthin [see p. 47) have been detected. 

 Astaxanthin rarely appears in mud. 



Fox, Updegraff" and Novelli, '" suggest three possible reasons for 

 the preferential storage of carotenes in ocean mud : 



(a) preferential oxidation of xanthophylls ; 



(b) selective assimilation followed by oxidative destruction of 

 xanthophylls by many marine animals, especially ilytrophic 

 (bottom feeding) animals ; and 



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