Capsaicin (CAP), the principal bioactive component of chili peppers (Capsicum annuum L.), is widely recognized for its anti-inflammatory properties. However, its oral bioavailability is low, likely due to extensive sulfonation metabolism. Despite the well-known pharmacological benefits of CAP, the role of sulfotransferase (SULT)-mediated sulfonation in modulating its therapeutic effects remains poorly understood. This study aims to elucidate the sulfonate metabolic profile of CAP, investigate the anti-inflammatory role of its sulfonate metabolite (CAP-S), and uncover the mechanisms underlying CAP-S's anti-inflammatory effects. In our study, the mono-sulfonate metabolite of CAP, designated as CAP-S ((E)-N-[(4-sulfo-3-methoxyphenyl)methyl]-8-methylnon-6-enamide), is identified using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) and proton nuclear magnetic resonance (