Structural elucidation, antioxidant and hepatoprotective activities of chemical composition from Jinsi Huangju (Chrysanthemum morifolium) flowers

Six new compounds (huangjusus A-F), including three caffeic acid glycosides (1–3), one quinic acid derivative (4), one dihydroflavone glycoside (11) and one monoterpene (31), together with thirty-eight known compounds (5–10, 12–30, 32–44), were obtained from “Jinsi Huangju” (Chrysanthemum morifolium Ramat.) flowers. Their structures were elucidated on the basis of the data obtained from different spectroscopic techniques. Among these compounds, five new (1–4 and 11) and ten known (5–9, 12, 13, 17, 40, and 42) compounds demonstrated significant 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging effects with IC50 values of 4.22–19.90 μM. Furthermore, three new compounds (1, 11, and 31) and seven known compounds (13, 19, 21, 29, 30, 39, and 41) exhibited potent hepatoprotective activities against N-acetyl-p-aminophenol (APAP)-induced toxicity in HepG2 cells with the cell survival rates of 61.53 %, 63.55 %, 60.01 %, 63.05 %, 59.75 %, 59.15 %, 61.07 %, 62.72 %, 58.86 %, and 58.76 % (positive control bicyclol, 58.41 %), respectively, at a concentration of 10 μM. These results indicate the potency of the flowers against radicals and in hepatoprotections.