HPLC analysis of flavonoids and secoiridoids in leaves of Ligustrum vulgare L. (Oleaceae)

Identification and quantification of flavonol glycosides and secoiridoids w as carried out on leaves of Ligustrum vulgare L. (Oleaceae) by means of HPL C-DAD and HPLC-MS analysis. In addition to previously reported secoiridoids (oleuropein, ligustaloside A, ligustaloside B, and ligstroside) four kaemp ferol glycosides (kaempferol 3-O-glucoside 7-O-rhamnoside, kaempferol 3,7-O -dirhamnoside, kaempferol 3-O-rhamnoside, and kaempferol 3-O-glucoside) and two quercetin glycosides (quercetin 3-O-glucoside 7-O-rhamnoside and querc etin 3,7-O-dirhamnoside) were present in leaves oft. vulgare L. Although se coiridoids accounted for nearly the 76% of the total leaf polyphenols conte nt (with ligustaloside A as the main component), kaempferol glycosides were also accumulated in the leaves of L. vulgare L. to a relatively high exten t (23%). Contribution of quercetin derivatives was minor under our experime ntal conditions. Our findings suggest that flavonol. glycosides may have a central role in both the ecology and the biology oft. vulgare L.