Comparative chemical and bioactivity studies on an endemic species Crataegus turcicus Dönmez and some Crataegus species growing in Türkiye

Crataegus turcicus Dönmez is a tree endemic species to Türkiye. This study aimed to assess its flower-bearing branches, leaves, and fruits in comparison with other well-known Crataegus species (C. monogyna, C. pentagyna, and C. orientalis) in terms of chemical composition and bioactivities. Firstly, the content of total phenolics (TPC), flavonoids (TFC), proanthocyanidin (TPAC), and anthocyanidin (TAC) were evaluated in different organs of Crataegus species. The highest TPAC was found in the hydroalcoholic extract of C. turcicus flower-bearing branches. Moreover, its all extracts had comparatively higher amounts of TPC, TFC, and TAC compared to other Crataegus species. The chemical screening by high-performance thin-layer chromatography (HPTLC) showed that C. turcicus plant parts were rich in chlorogenic acid, neochlorogenic acid, quercetin, vitexin derivatives, epicatechin, procyanidin, and cyanidin glycosides and their quantities were evaluated by high-performance liquid chromatography (HPLC). Based on in-vitro antioxidant activity tests, the flower-bearing branches of C. turcicus showed the highest antioxidant activity by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) test among the assessed antioxidant assays. Additionally, hydroalcoholic extracts of C. turcicus at 1 mg/mL concentration significantly reduced LPS-induced nitric oxide, tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) production in RAW 264.7 cells more potently than indomethacin (positive control). In addition to its remarkable anti-inflammatory activity, C. turcicus extracts exhibited analgesic activity by reducing prostaglandin E2 (PGE2) levels. Keywords: Crataegus L.; Crataegus turcicus; phenolic profiling; antioxidant activity; anti-inflammatory activity; analgesic activity