Quinic acid(QA)has antioxidant,anticancer and anti-inflammatory effects,but its pro-tective effect against bovine mastitis remains to be further investigated.The aim of this study was to investigate the inhibitory effects and mechanisms of quinic acid(QA)on lipopolysaccharide(LPS)-induced inflammation and pyroptosis in bovine mammary epithelial cells(MAC-T)and mouse mammary tissues.The CCK-8 method was applied to screen the treatment concentration of QA in MAC-T cells.The ELISA method was used to detect the expression levels of inflammatory factors,oxidative stress factors and pyroptosis indicators.The distribution of CD3 in mouse mam-mary tissues was detected by the immunohistochemical method.p65 nuclear translocation was measured by immunofluorescence.Western blot was performed to test the protein and phosphoryl-ation levels of NF-κB,the inflammasome of NOD-like receptor(NLRP3),Caspase-11 and gasder-min D(GSDMD).The results showed that QA(20,40 and 60 mg/L)significantly increased the activity of MAC-T cells(P＜0.05).QA treatment significantly reduced LPS-induced expression of inflammatory factors(TNF-α,IL-1β and IL 6),oxidative stress indicators(COX-2 and iNOS)and pyroptosis indicators(ROS,LDH and IL-18)in both MAC-T cells and mouse mammary tissues in a manner of dose-dependence(P＜0.05).Moreover,after intraperitoneal injection of QA at 5,10 and 20 mg/kg,respectively,the expression of T-lymphocyte marker CD3 induced by LPS was sig-nificantly downregulated in mouse breast tissues(P＜0.05).In addition,QA significantly de-creased the LPS-induced expression of NF-κB(IκBα,p65,p-IκBα and p-p65),inflammasome(NL-RP3,ASC and Caspase-1),Caspase-11 and DSDMD in both MAC-T cells and mouse mammary tis-sues,and inhibited p65 nuclear transfer in MAC-T cells(P＜0.05).Overall,the above results indi-cate that QA inhibits inflammatory response and pyroptosis through NF-κB and NLRP3 inflamma-some in both MAC-T cells and mouse mammary tissues.The results of this study provide novel da-ta on the prevention and treatment of mastitis by plant active ingredients.