Mediterranean Asteraceae as Natural Sources of Antioxidants and Enzyme Inhibitors: A Case Study on Urospermum dalechampii and Andryala integrifolia From Tun

ABSTRACT

This study investigated the phenolic composition, antioxidant capacity, and key enzyme‐inhibitory activities of hydroethanolic leaf extracts from two Mediterranean Asteraceae, Urospermum dalechampii and Andryala integrifolia , from Tunisia. U. dalechampii exhibited higher total phenolic content (62.84 mg GAE/g crude extract), whereas A. integrifolia  showed higher flavonoids (34.55 mg QE/g crude extract). The UHPLC‐DAD‐MS analysis revealed caffeoylquinic acid isomers, flavonols (quercetin and kaempferol types), and flavones (luteolin derivatives) in both species, while cynarine was detected in U. dalechampii .  Some compounds were specific, such as caftaric acid, which was detected only in U. dalechampii  leaf extract. Both species exhibited notable antioxidant capacities, with U. dalechampii  showing stronger radical‐scavenging activity (DPPH: EC ₅₀   = 0.95 mg/mL; ABTS: EC ₅₀   = 0.72 mg/mL), whereas A. integrifolia  displayed higher reducing power (FRAP: EC ₅₀ = 5.40 mg/mL) and copper‐chelating activity (EC ₅₀   = 1.72 mg/mL). A. integrifolia  showed marked inhibition of tyrosinase (IC ₅₀   = 0.54 mg/mL), α‐glucosidase (IC ₅₀   = 1.9 mg/mL), and lipase (IC ₅₀  = 9.7 mg/mL). Both leaf extracts from studied species inhibited AChE, while only A. integrifolia  inhibited BChE (IC ₅₀   = 8.63 mg/mL). No cytotoxicity was detected at 100 µg/mL in human hepatocarcinoma (HepG2), neuroblastoma (SH‐SY5Y), embryonic kidney (HEK‐293), and murine melanoma (B16) cells. These results highlight these two plants as a promising source of multifunctional bioactive compounds and demonstrate that unexploited wild plants could offer new prospects for pharmaceutical and nutraceutical applications.