Molecular weights and empirical formulas of the xanthophylls of Vaucheria

The chloroplast pigments of the algal classes Eustigmatophyceae and Xanthophyceae. II. Xanthophyceae

“…On the other hand, Stransky & Hager (1970a), claimed that Botrydium and other yellow-green algae which contain diadinoxanthin also contain diatoxanthin but never zeaxanthin. The strongly adsorbed non-epoxy pigment described by Falk & Kleinig (1968) as trollixanthin is probably heteroxanthin (Strain et al, 1968(Strain et al, , 1970Stransky & Hager, 1970a).…”

“…Of the xanthophylls, three have been misidentified in the recent past, including diadinoxanthin as antheraxanthin by Whittle & Casselton (1969) studying Tribonema aequale. Strain et al (1968Strain et al ( , 1970 have emphasised the difficulty of identifying~elosely related xanthophylls, such as diadinoxanthin, antheraxanthin and lutei~5,6-epoxide, using only chromatographic properties and absorption spectra in the visible region. When Kleinig & Egger (1967) claimed the isolation of antheraxanthin from Vaucheria and Botrydium, they characterised it by comparing its chromatographic behaviour, spectral properties and synthetic derivatives with those of authentic antheraxanthin.…”

“…Several attempts had been made to identi~ the chloroplast pigments of the Xanthophyceae (Kuhn & Brockman, 1932;~arter, Heilbron & Lythgoe, 1939;Seybold, Egle & Hiilsbruch, 1941 ;Heilbron, 1942;Strain, Manning & Hardin, 1944;Jamikorn, 1954;Strain, 1958;gestfik, 1963;Allen et al, 1964;Thomas & Goodwin, 1965;Chapman & Haxo, 1966) before Kleinig & Egger (1967) reported that Vaucheria and Botrydium contained p-carotene, chlorophyll a, antheraxanthin, three tri-esters of the previously undescribed xanthophyll vaucheriaxanthin, an unknown pigment which was subsequently identified by Falk & Kleinig (1968) as trollixanthin, and traces of cryptoxanthin epoxide and zeaxanthin, the latter pigment being produced by a light-induced conversion of antheraxanthin (Kleinig, 1967). Subsequent studies largely fall into two groups, those primarily dealing with the correct identification of the pigments (Falk & Kleinig, 1968;Egger, Nitsche & Kleinig, 1969;Strain et al, 1968Strain et al, , 1970Stransky & Hager, 1970a) and those primarily concerned with recognition of the fact that some of the unicellular forms belong to a separate taxonomic group (Whittle & Casselton, 1969, 1975Guillard & Lorenzen, 1972) corresponding to the Eustigmatophyceae of Hibberd & Leedale (1970, 1971b, 1972. Falk & Kleinig (1968) claimed that Tribonema had the same pigments as Vaucheria and Botrydium, except that the minor xanthophyll cryptoxanthin was missing.…”

“…Whittle & Casselton (1969) agreed with them and also suggested that the pigments of Mischococcus sphaerocephalus resembled those of Tribonema. It now appears that the pigment which was isolated by both Kleinig & Egger (1967) and Whittle & Casselton (1969) and identified as antheraxanthin is, in fact, the closely related xanthophyll diadinoxanthin (Strain et al, 1968(Strain et al, , 1970Egger et al, 1969;Stransky & Hager, 1970a). Stransky & Hager (1970a) used a very sensitive system of thin-layer chromatography (TLC) in conjunction with infrared spectroscopy and microchemical tests for identifying functional groups to study the carotenoids of eight members of the Xanthophyceae sensu stricto.…”

“…They also detected stereoisomers of vaucheriaxanthin, diadinoxanthin and heteroxanthin. Strain et al (1968Strain et al ( , 1970, after pigment separation on very large sucrose columns and purification by rechromatography and crystallisation, identified individual xanthophylls by comparative infrared, NMR and mass spectrum analysis. They claimed that the principal xanthophylls of both Vaucheria and Tribonema were heteroxanthin, a pigment more strongly adsorbed than neoxanthin which they named and for which they also suggested a structure, diatoxanthin and diadinoxanthin.…”