Organic extracts of the flowers of Helichrysum kraussii and H. odoratissimum contain several bioactive flavonoids, characterized by 1H NMR, 13C NMR and mass spectrometry. Four flavonoids, 5,6-dihydroxy-3,7,8-trimethoxyflavone, 5,7-dihydroxy-3-methoxyflavone, 3′,4′,5,7-tetrahydroxy-3-methoxyflavone and 3′,4′,3,5-tetrahydroxy-7-methoxyflavone, have antioxidant activity by the DPPH free radical assay, while 5,6-dihydroxy-3,7,8-trimethoxyflavone and 3′,4′,3,5-tetrahydroxy-7-methoxyflavone have promising anti-inflammatory activity.
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