Silene vulgaris subsp. macrocarpa leaves and roots from Morocco: assessment of the efficiency of different extraction techniques and solvents on their antioxidant capacity, brine shrimp toxicity and phenolic characterization

Abstract

This study was undertaken to investigate the effect of various solvents and techniques on the extractability of antioxidant compounds, particularly phenolics, from leaves and roots of Silene vulgaris subsp. macrocarpa grown wild in Morocco. Maceration and hot extraction with methanol or water and Soxhlet ethanol extraction were utilized. Aimed at establishing the potential safety of the extracts, Artemia salina lethality bioassay was performed. All the extracts were found to be non-toxic, except for the leaf Soxhlet ethanol. The antioxidant potential of the extracts was evaluated in vitro by DPPH, reducing power, and ferrous ions chelating activity assays. The leaf extracts displayed noticeable radical scavenging and chelating activities, and maceration with methanol (Mac-MeOH) resulted the most suitable extraction method for an effective recovery of antioxidants; further, the root Mac-MeOH extract demonstrated good chelating properties (IC₅₀ = 335.49 ± 0.70 µg/mL). Thus, leaf and root Mac-MeOH extracts were subjected to phytochemical investigations. The total phenolic, flavonoid and condensed tannin content was determined spectrophotometrically. Thirteen polyphenolic compounds were positively identified, by HPLC-PDA-ESI-MS, in the leaf extract for the first time, with p-coumaric acid derivatives being the most abundant ones (81%), whereas only catechin and procyanidin B1 were found in the root extract.

Keywords:

• Silene vulgaris (Moench) Garcke subsp. macrocarpa Turrill
• extraction solvent/technique
• antioxidant activity; Artemia salina Leach
• phenolic compounds
• HPLC-PDA-ESI-MS

Acknowledgements

This work was carried out within the program Erasmus+/KA107 Higher Education Agreement between the University of Messina (Italy) and the Moulay Ismail University, Meknes (Morocco). The authors gratefully thank Prof. Jalal el Oualidi for plant identification. The authors are thankful to the Foundation “Prof. Antonio Imbesi”, Shimadzu and Merck Life Science Corporations for the support.

Disclosure statement

The authors declare no potential conflict of interest, including any financial interest.