xanthophyll Chem.
(ˈzænθəʊfɪl)
[ad. F. xanthophylle (Berzelius), f. Gr. ξανθός yellow + ϕύλλον leaf.]
a. The yellow colouring-matter of leaves in autumn, a constituent or derivative of chlorophyll; also called phylloxanthin. (Now recognized as an oxygenated carotenoid identical with lutein.)
| 1838 R. D. Thomson in Brit. Ann. 334. 1868 Watts Dict. Chem. V. 1052 Xanthophyll... Nothing certain is known respecting its composition, or of the manner in which it is formed from chlorophyll. 1891 Science-Gossip XXVII. 46/2 When the life of the leaf is destroyed by frost or drought, the chlorophyll is rapid changed to xanthophyll. 1934 Science 25 May 488/2 Xanthophyll (lutein) appears to be structurally related to α-carotene and zeaxanthin to β-carotene. 1945 Biol. Rev. XX. 115/1 Following a convention which is being more widely adopted the specific pigment which has been termed ‘xanthophyll’ is here called ‘lutein’. 1964 E. J. H. Corner Life of Plants i. 5 The orange-yellow carotin and the yellow xanthophyll..cause the yellow colour of those parts of variegated leaves unable through some deficiency to make chlorophyll. |
b. [After R. Kuhn et al. 1931, in Zeitschr. f. physiol. Chem. CXCVII. 141.] Any of a group of yellow pigments (as lutein and violaxanthin) that are oxygenated carotenoids.
| 1931 Chem. Abstr. XXV. 3659 The term xanthophyll should be used to designate the entire group of OH-contg. carotenoids with 40 C atoms. The individuals thus far known are: lutein and zeaxanthin.., violaxanthin.., and fucoxanthin. 1952 Chem. & Engin. News 7 Jan. 104/2 Two of the rules on carotenoids adopted at the London Conference of 1947 were revised to give the following text:.. The name ‘xanthophyll’ is a group name..for carotene derivatives of natural origin which are soluble in alcohol and are not saponifiable. 1955 G. M. Smith Cryptogamic Bot. (ed. 2) I. ii. 12 There are several xanthophylls [in the Chlorophyta] not found in other algae, and of these lutein is the most abundant. 1976 Monitor (McAllen, Texas) 27 Sept. 4a/2 Brown tannin pigments blend with xanthophylls to produce yellow-gold and gold-brown leaves. |
Hence xanthoˈphyllic a., of or containing xanthophyll.
| 1941 Biol. Bull. LXXX. 451 In the herbivores, the echinoids too contained some xanthophyllic pigments without exception. 1982 Monitor (McAllen, Texas) 2 Apr. 6-c/2 Miss Arden claims she now has a substance, extracted from a xanthophyllic-carotin mixture, which will drain the last vestige of visibility from succeeding generations of frogs but she feels it would serve no useful purpose. |