Contribution of individual flavonoids in <i>Lysimachia</i> species to the antioxidant capacity based on HPLC-DPPH assay

<p>Quantitative phytochemical characterisation of the chief flavonoid aglycones in the hydrolysed <i>Lysimachia</i> extracts revealed the dominance of kaempferol, quercetin and myricetin in <i>L. vulgaris</i>, <i>L. nummularia</i>, <i>L. punctata</i>, <i>L. christinae</i>, <i>L. ciliata</i> and <i>L. clethroides,</i> respectively<i>.</i> Due to the significant radical scavenging capacity of the samples, the contribution of the individual aglycones to the total antioxidant activity became of interest<i>.</i> Therefore, a HPLC method coupled to pre-column DPPH scavenging assay was developed. Differences in the six <i>Lysimachia</i> species’ phenolic composition regarding their participation to the antioxidant activity were revealed. The participation of the three investigated flavonoids to the radical quenching activity was the highest (91.2%) in the <i>L. vulgaris</i> sample, the lowest in <i>L. christinae</i> sample with 29.6%. In <i>L. vulgaris</i> sample, the 76.3% contribution of quercetin to the scavenger capacity was the highest peak area decrement ratio among the investigated samples.</p>