Comparative Phytochemical Profile, Antioxidant, Antimicrobial and In Vivo Anti-Inflammatory Activity of Different Extracts of Traditionally Used Romanian Ajuga genevensis L. and A. reptans L. (Lamiaceae).

Anca Toiu,Andrei Mocan,Laurian Vlase,Dan Cristian Vodnar,Cadmiel Moldovan,Ilioara Oniga,Ana-Maria Gheldiu,Alina Elena Pârvu

doi:10.3390/molecules24081597

Abstract

Several Ajuga species are used in Romanian folk medicine for their antioxidant, antimicrobial and anti-inflammatory properties, to treat pain, fever or arthritis. Still, the active compounds responsible for these effects and their mechanism of action are scarcely known. This research was designed to investigate the phytochemical profile (e.g. iridoids, polyphenolic compounds, phytosterols), as well as the biological potential (antioxidant, antibacterial, antifungal, anti-inflammatory properties) of two selected Ajuga species collected from different regions of Romanian spontaneous flora. The main compounds identified in A. reptans aerial parts extracts were 8-O-acetylharpagide, isoquercitrin and β-sitosterol, whilst in A. genevensis were 8-O-acetylharpagide, luteolin and campesterol. The extracts were screened for their antioxidant potential using different methods (DPPH, TEAC, EPR) and the results showed a good activity, in accordance with the polyphenol content (18–26 mg GAE/g dw). The antifungal activity on the tested strains was good. The determination of few parameters linked with the inflammatory mechanism allowed the assessment of in vivo anti-inflammatory potential. Ajuga reptans and A. genevensis ethanol extracts had anti-inflammatory activity through lowering the oxidative stress, phagocytosis, PMN and total leukocytes. The best anti-oxidative and anti-inflammatory activity was observed for the Ajuga reptans 100 mg dw/mL extract when compared with diclofenac, thus the dose could be correlated with the pharmacological effect. These findings provide substantial evidence that both selected Ajuga species have the potential to be valued as sources of phytochemicals in effective anti-inflammatory herbal preparations.

Highlights

Over the last decades, medicinal plants have historically proved to be a valuable source of drug development candidates due to their important reserve of bioactive compounds [1]
The main reason for this concept was that usually, the methanol extract is obtained for the purpose of phytochemical analysis, in laboratory, a rapid and simple extraction method is useful for the characterization of vegetal products (30 min at 60 ◦ C), whereas the extract used in phytotherapy is generally the ethanol one, obtained by maceration at room temperature (7 days by maceration)
The most abundant compounds identified in the aerial parts of Ajuga reptans were isoquercitrin β-sitosterol and 8-O-acetylharpagide

Summary

Introduction

Medicinal plants have historically proved to be a valuable source of drug development candidates due to their important reserve of bioactive compounds [1]. In order to obtain new herbal medicines with important pharmacological properties, the secondary metabolites found in plants are excellent candidates. Omnipresent in vegetal products and important component of human nutrition, phenolics with antioxidant effects are of major interest for their valuable promising pharmacological properties [2]. Phytochemicals are biomolecules formed in plants, that occur in herbal drugs or phytopharmaceuticals, bioactive compounds which could lower the risk of certain disorders [3]. In this context, in order to obtain new herbal preparations, additional investigations into unexplored herbal products used in phytotherapy are required

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Results

Conclusion