First discovery of triterpenoids and sterols from Cotinus coggygria var. cinereus Engl. with anti-inflammatory and antibacterial activities

Abstract This study led to the isolation of 17 triterpenoids, including two lanostane-type ( 1 and 2 ), two dammarane-type ( 3 and 7 ), ten tirucallane-type ( 4 and 8 − 16 ), and three oleanane-type ( 17 − 19 ) triterpenoids, as well as nine sterols ( 5 , 6 , and 20 − 26 ) from Cotinus coggygria var. cinereus Engl, which were first discovered from the genus Cotinus . Among them, coggygrenoids A−D ( 1 − 4 ), coggygrerol A ( 5 ), and coggygrerol B ( 6 ) are undescribed compounds. Additionally, seven flavonoids ( 27 − 33 ) were also isolated from this plant . Compound 15 displayed inhibitory activities in LPS-induced RAW 264.7 cells with an IC 50 value 6.81 ± 0.15 μM. Molecular docking demonstrated that 15 exhibited favorable affinity for NLRP3 and iNOS. In vitro and in vivo antibacterial evaluations indicated that coggygrnoid C ( 3 ) exhibited significant inhibitory activity against methicillin-resistant Staphylococcus aureus ATCC BAA-1717 (USA300), with An MIC of 8 μg/mL. Further mechanistic investigations demonstrated that 3 exerted antibacterial activity by compromising the integrity of the cell wall and membrane. Notably, the combination of 3 with ampicillin exhibited an additive antibacterial effect. In the Galleria mellonella infection model, compound 3 exhibited comparable activity to that of the positive control at 20 mg/kg. These findings suggest that triterpenoids of C. coggygria are potential antibacterial lead agents. Graphical Abstract