anthocyanins

Red to blue (hence cyan-) plant pigments. Flowers pollinated by animals, and fruits dispersed by them, are often brightly coloured with anthocyanins to make them attractive. Anthocyanins are also said to protect underlying tissues from excessive light (including ultraviolet light), particularly in young foliage.

This definition is abridged from A – Z of tree terms: A companion to British arboriculture.
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