- Analysis of palmitoyl apo-astaxanthinals, apo-astaxanthinones, and their epoxides by UHPLC-PDA-ESI-MS
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Food products enriched with fatty acid-esterified xanthophylls may result in deviating dietary apo-carotenoids. Therefore, free astaxanthin and its mono- and dipalmitate esters were subjected to two degradation processes in a methanolic model system: light-accelerated autoxidation and hypochlorous acid/hypochlorite (HOCl/OCl-) bleaching. Reversed phase ultrahigh-performance liquid chromatography photodiode array with in-line electrospray ionization mass spectrometry (RP-UHPLC-PDA-ESI-MS) was used for assessment of degradation products. Apo-astaxanthinals and -astaxanthinones containing 3 (apo-9) to 10 (apo-8′) conjugated double bonds were found upon autoxidation for all three types of astaxanthin (except free apo-8′-astaxanthinal). Fragmentation of [M + H]+ and [M + Na]+ parent masses of apo-astaxanthins from dipalmitate astaxanthin indicated palmitate esterification. Astaxanthin monopalmitate degradation resulted in a mixture of free and palmitate apo-astaxanthins. HOCl/OCl- rapidly converted the astaxanthins into a mixture of epoxy-apo-9- and epoxy-apo-13-astaxanthinones. The palmitate ester bond was hardly affected by autoxidation, whereas for HOCl/OCl- the ester bond of the apo-astaxanthin palmitoyl esters was degraded.
- Weesepoel, Yannick,Gruppen, Harry,De Bruijn, Wouter,Vincken, Jean-Paul
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- Reaction of astaxanthin with peroxynitrite
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The in vitro reactivities of astaxanthin toward peroxynitrite were investigated and the reaction products after scavenging with peroxynitrite were analyzed in order to determine the complete mechanism of this reaction. A series of carotenoids, 13-apo-astaxanthinone (1), 12′-apo-15′- nitroastaxanthinal (2), 12′-apo-astaxanthinal (3), 10′-apo- astaxanthinal (4), 9-cis-14′-s-cis-15′-nitroastaxanthin (5), 14′-s-cis-15′-nitroastaxanthin (6), 13-cis-14′-s-cis- 15′-nitroastaxanthin (7), 10′-s-cis-11′-cis-11′- nitroastaxanthin (8), 13,15,13′-tri-cis-15′-nitroastaxanthin (9), 9-cis-astaxanthin (10), and 13-cis-astaxanthin (11), were isolated from the reaction products of carotenoids with peroxynitrite. Our previous studies achieved for the first time the isolation of nitro derivatives from the reaction of astaxanthin with peroxynitrite. Here we identify the major remaining reaction products of this reaction and investigate the stabilities of the nitro astaxanthins.
- Hayakawa, Tsutomu,Kulkarni, Aditya,Terada, Yukimasa,Maoka, Takashi,Etoh, Hideo
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- Synthese von optisch aktiven, natuerlichen Carotinoiden und strukturell verwandten Naturprodukten. IX. Synthese von (3R)-Hydroxyechinenon, (3R,3'R)- und (3R,3'S)-Adonixanthin, (3R)-Adonirubin, deren optischen Antipoden und verwandten Verbindungen
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The synthesis of racemic and optically active hydroxyechinenone (12-14), adonixanthin (16-19), adonirubin (22-24), meso-astaxanthin (26) and their corresponding diosphenols (15, 20, 21, 25, 27, 28, and 29) by Wittig reaction is reported, starting from suitable C15-phosphonium salts and C10-aldehydes.
- Bernhard, Kurt,Englert, Gerhard,Mayer, Hans,Mueller, Robert K.,Ruettimann, August,et al.
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p. 2469 - 2484
(2007/10/02)
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