HPLC Analysis of Polyphenolic Compounds in Lysimachia nummularia L. and Comparative Determination of Antioxidant Capacity

Abstract

Lysimachia nummularia L. is a perennial herbaceous plant rich in bioactive compounds, which can be utilized for medicinal purposes. The present work aims to analyze the phenolic compounds from different parts of the Lysimachia nummularia L. plant using the HPLC technique: Lysimachiae radix (the root part), Lysimachiae herba (the aerial part), Lysimachiae flores (flowers). In order to determine the phenolic compounds, extraction from the three categories of vegetable products was performed with ethanol 70% (v/v) using three extraction methods: (i) Soxhlet extraction, (ii) maceration and (iii) ultrasonic-assisted extraction. The content of polyphenols was determined by the Folin–Ciocalteu method, and the antioxidant activity was evaluated by the DPPH, ABTS, FRAP and CUPRAC methods. The antioxidant activity was correlated with the content of phenolic compounds in the analyzed extracts. The following phenolic compounds were separated, identified and quantified: 3-O-methylgallic, gallic, ferulic, caffeic, chlorogenic, p-coumaric acids and trans-resveratrol. According to the experimental data, the highest content of total polyphenols was observed in the hydroethanolic extract from Lysimachiae flores (22.10 ± 1.48 mg gallic acid/g), which also presented remarkable antioxidant activity.