Phytochemistry: Structure of the blue cornflower pigment

@article{Shiono2005PhytochemistrySO,
  title={Phytochemistry: Structure of the blue cornflower pigment},
  author={Masaaki Shiono and Naohiro Matsugaki and Kǒsaku Takeda},
  journal={Nature},
  year={2005},
  volume={436},
  pages={791-791}
}
The same anthocyanin pigment makes roses red but cornflowers blue, a phenomenon that has so far not been entirely explained. Here we describe the X-ray crystal structure of the cornflower pigment, which reveals that its blue colour arises from a complex of six molecules each of anthocyanin and flavone, with one ferric iron, one magnesium and two calcium ions. We believe that this tetrametal complex may represent a previously undiscovered type of supermolecular pigment. 

Blue metal complex pigments involved in blue flower color

  • K. Takeda
  • Chemistry, Medicine
    Proceedings of the Japan Academy. Series B, Physical and biological sciences
  • 2006
The author focuses on the investigations of the blue metal complex pigments involved in the bluing of flowers, commelinin from Commelina commusis, protocyanin from Centaurea cyanus, protodelphin from Salvia patens and hydrangea blue pigment.

Structure of commelinin, a blue complex pigment from the blue flowers of Commelina communis.

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This review focuses on the advances in the last 15 years, and cites 149 references, in understanding blue flower coloration since the comprehensive review by Goto and Kondo in 1991.

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The mixing conditions to reconstruct the same blue color as observed in the sepals were studied and indicated that in the hydrangea-blue complex 1 might be under equilibrium between chelating and nonchelating structures having an interaction with 2.

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Anthocyanins are naturally occurring plant pigments responsible for the red, blue, and purple colors of the majority of fruits, flowers, and leaves. The pH-dependent ground-state chemistry of

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This review revisits this phenomenon to provide a comprehensive description of the nature of binding and of spectral modifications occurring in copigmentation complexes, in which charge transfer plays an important role.

Biosynthesis of plant pigments: anthocyanins, betalains and carotenoids.

Three classes of pigments act as visible signals to attract insects, birds and animals for pollination and seed dispersal, and protect plants from damage caused by UV and visible light.
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