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QUANTITATIVE ANALYSIS OF FLAVONOIDS AND PHENOLIC ACIDS IN TWENTY-ONE Hypericum TAXA

The content of flavonoids and phenolic acids in the aerial parts of twenty one Hypericum taxa collected over two consecutive seasons was investigated by spectrophotometric methods. All taxa examined, contained flavonoids and phenolic acids in different quantities, although the differences between species or year's harvest were not found to be significant. The quantity of flavonoids ranged from 0.13 to 1.59%. The highest content of flavonoids was found in the samples of H. japonicum (1.59%) and H. perforatum (1.51%) collected in 2011, while the samples of H. androsaemum and H. balearicum collected in 2010, comprised the lowest flavonoid amount (0.13%). The content of phenolic acid in the investigated samples, was found to be between 0.72-10.37%. The samples of H. perforatum were found to contain the highest quantity of phenolic acids (10.37% and 10.23%), whereas the sample of H. orientale collected in 2011, showed the lowest amount of phenolic acids (0.72%). The variable content of polyphenols examined here, probably reflects adaptation to seasonal changes in its environment. The occurrence of these metabolites in the taxa explored, hopefully will contribute to future understanding of their pharmacological properties and activity.

Hypericum; flavonoids; phenolic acids

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