Flavonoid-Rich Metabolite Profiling and Anti-Inflammatory Activity of Adonis aestivalis L.

Adonis aestivalis L. is a member of the genus Adonis, traditionally associated with cardiotonic compounds; however, its polyphenolic composition and anti-inflammatory potential warrant further phytochemical and pharmacological evaluation. The aim of this study was to characterise the metabolic profile of A. aestivalis extracts, with a focus on flavonoid-containing components, and to evaluate their anti-inflammatory activity in LPS-stimulated RAW 264.7 macrophages. Aqueous, 50% ethanolic, and absolute ethanolic extracts were analysed by HPLC–ESI–QTOF-MS/MS in positive and negative ionisation modes. The ethanolic extracts exhibited the most diverse chromatographic profiles, with a predominance of flavonoids, including derivatives of kaempferol, quercetin, and apigenin, as well as C-glycosylated flavones such as orientin, isoorientin, vitexin, and isovitexin. Phenolic acids, fatty acid derivatives, organic acids, and adonitol were also tentatively identified. The occurrence of glycosylated, acylated, and glucuronidated flavonoid derivatives indicates marked structural diversity within the flavonoid fraction. In biological assays, the 50% ethanolic extract showed no cytotoxicity towards RAW 264.7 cells at concentrations up to 50 μg/mL and produced a statistically significant but moderate reduction in LPS-induced NO production. Furthermore, it attenuated the release of pro-inflammatory cytokines, including IL-6, IL-1β, and TNF-α, to varying degrees. The data obtained indicate that A. aestivalis is a promising source of flavonoid-containing extracts with anti-inflammatory potential and may provide a foundation for further studies aimed at developing standardised phytochemical preparations with a defined polyphenolic profile. Further quantitative phytochemical analysis, bioactivity-guided fractionation, mechanistic studies, safety assessment, and in vivo evaluation are required to confirm the active constituents and therapeutic relevance of the extracts.