Comparison of phenolic compound accumulation profiles in eight evergreen woody core eudicots indicating the diverse ecological adaptability of Camellia sinensis

- In identified eight species, the total flavanols were abundant, except the species of Oleaceae.
- EGCG was the predominant compound in Camellia sinensis, but almost not be detected in the other seven specises.
- Proanthocyanidins were the dominant flavonoids in roots of some species.
- Some phenolic acids and flavonols were distributed in all the eight species.

Phenolic compounds, such as flavanols, flavones, flavonols, anthocyanins, and phenolic acids, contribute to a plant's adaptation to their ecological niches. These compounds serve as attractants of organisms beneficial to the plants or as defence against other biotic and abiotic factors during the plant evolution. In this paper, the accumulation patterns of phenolic compounds in the eight evergreen woody core eudicots indicated divergent and convergent evolution of plant secondary metabolites. The results indicated some phenolic acids and flavonols were distributed in all the studied eight evergreen woody plants, within Oleaceae, Theaceae, Caprifoliaceae and Celastraceae, with different accumulation profiles. The flavan-3-ols, monomeric catechins, and polymeric proanthocyanidins, were undetectable in Osmanthus fragrans, Ligustrum lucidum, and Fraxinus mariesii of Oleaceae, but highly accumulated in the other five species, especially in Camellia sinensis of Theaceae. It indicated Camellia sinensis evolved great ecological adaptive capacity to prevent herbivores, insect pests, and microbial pathogens.