Chlorogenic (5-CQA), 1,5-, 3,5-, 4,5-and 3,4-dicaffeoylquinic (DCQA) acids were identified and quantified in the methanol extracts of Inula oculus-christi L., I. bifrons L., I. aschersoniana JANKA var. aschersoniana, I. ensifolia L., I. conyza (GRIESS.) DC. and I. germanica L. by HPLC analysis. The amount of 5-CQA varied from 5.48 to 28.44 mg/g DE and the highest content was detected in I. ensifolia. 1,5-DCQA (4.05-55.25 mg/g DE) was the most abundant dicaffeoyl ester of quinic acid followed by 3,5-DCQA, 4,5-DCQA and 3,4-DCQA. The extract of I. ensifolia showed the highest total phenolic content (119.92 � 0.95 mg GAE/g DE) and exhibited the strongest DPPH radical scavenging activity (69.41 � 0.55 %). I. bifrons extract was found to be the most active sample against ABTS * + (TEAC 0.257 � 0.012 mg/mL) and the best tyrosinase inhibitor. The studied extracts demonstrated a low inhibitory effect towards acetylcholinesterase and possessed low cytotoxicity in concentration range from 10 to 300 μg/mL toward non-cancer (MDCK II) and cancer (A 549) cells. Figure 2. HPLC chromatograms of the studied extracts and standard mixture.[a] Results are presented as mean � SD from three replicates (n = 3). Means in the columns with the same letter are not significantly different from each other (p > 0.05) (t-test).

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