Unraveling the Anti-inflammatory Mechanism of Dolichos lablab Flower Extract: Synergistic Action of Bioactive Flavonoids via Multi-target Modulation

Abstract

Abstract：Dolichos lablab Flos (DLF), a medicinal and edible homologous plant, possesses rich nutritional and medicinal value. This study aimed to systematically characterize its bioactive compounds and elucidate their antioxidant and anti-inflammatory mechanisms. Using UPLC-Q-MS/MS, 44 compounds were identified, predominantly flavonoids and fatty acids. Network pharmacology analysis predicted that key flavonoids--such as quercetin, apigenin, kaempferol, luteolin, cirsimaritin, daidzein, genistein, and isorhamnetin--modulate inflammatory responses via 32 core targets (e.g., TNF, IL6, PTGS2) and pathways including proteoglycans in cancer and TNF signaling. Molecular docking confirmed strong binding affinities of apigenin (∆G = -10.9 kcal/mol with TNF) and quercetin (∆G = -10.3 kcal/mol with PTGS2). HPLC analysis identified multiple bioactive constituents in purity-BLDLF, with the predominant compounds being apigenin (5.72%) and quercetin (4.06%). In vitro assays using the n-butanol extract layer (BLDLF) demonstrated potent anti-inflammatory activity in LPS-stimulated RAW 264.7 macrophages. At 100 µg/mL, BLDLF significantly suppressed pro-inflammatory cytokines (TNF-α: 335 pg/mL; IL-6: 48.6 pg/mL), inhibited NO production (5.6 µmol), reduced ROS generation by 64.4%, and decreased cell apoptosis. This study provides a holistic strategy for valorizing Dolichos lablab flower as a sustainable source of anti-inflammatory ingredients, highlighting its potential for functional foods and pharmaceutical applications.