Characterization of Phenolic Compounds of Arnica montana Conventional Extracts

Arnica montana L. (Asteraceae family) is a plant commonly used in traditional medicine, and several reports have characterized this plant’s bioactivities, especially its phenolic compounds. These compounds are well known for their numerous beneficial biological properties. Consequently, industry stakeholders from the feed, food, cosmetic, and pharmaceutical sectors are seeking extracts rich in phenolic compounds, which could be interesting for the development of bio-based applications. The objective of the present study was to characterize the phenolic profile of this species to lay the groundwork for further optimization studies to obtain the highest amount of phenolic compounds. Therefore, A. montana was extracted with an ethanol/water ratio of 80:20 (v/v) at room temperature for 1 h, and phenolic compounds were identified and quantified through UPLC (HPLC Dionex Ultimate 3000) with a mass detector (TSQ Quantis). In the extract, phenolics belonging to different groups were identified, namely eriodictyol-O-glucuronide (flavanone), hispidulin and luteolin (flavones), kaempferol and 6-methoxykaempferol, (flavonols), p-coumaric, feruloylquinic, caffeoylquinic, and dicaffeoylquinic isomers (hydroxycinnamic acids). However, only four of them could be quantified: kaempferol and the three hydroxycinnamic acids. The total phenolic content (mg/g of dry sample) was estimated to be 27.34 mg/g, with the most prevalent compounds being the dicaffeoylquinic acids (accounting for 79.5% of the total phenolics). It has been demonstrated that dicaffeoylquinic acids present anti-inflammatory and antioxidant activities, which have been linked to several beneficial effects. Thus, obtaining phenolic-rich extracts of A. montana may allow us to exploit this plant’s significant biological properties, and it could be a new ingredient for developing new applications in the nutraceutical, cosmetic, and/or pharmaceutical industries.