In vitro Anti-Inflammatory Activities and Phytochemical Fingerprints of Fractions of Detarium microcarpum Stem Bark

Abstract Chronic inflammation represents a significant global health burden implicated in the pathogenesis of various diseases, including cardiovascular disorders, cancer, type 2 diabetes, and autoimmune conditions. The limitations of conventional non-steroidal anti-inflammatory drugs (NSAIDs), such as adverse effects and diminishing efficacy, necessitate the exploration of alternative therapies, particularly those derived from medicinal plants. This study investigated the anti-inflammatory activity and chemical composition of petroleum ether (PE), dichloromethane (DCM), and hydro-methanol (HMF) fractions of Detarium microcarpum stem bark using in vitro models and HPLC fingerprinting. Anti-inflammatory activity was assessed via erythrocyte membrane stabilization, inhibition of protein denaturation, and heat-induced albumin denaturation assays, with Aspirin serving as the standard control. HPLC was employed to identify phytoconstituents in each fraction. All fractions exhibited significant (p < 0.05) dose-dependent anti-inflammatory activity, with the DCM fraction demonstrating the most potent membrane stabilization effect with IC50 value of 0.9524 mg/mL and the HMF fraction showing the greatest heat-induced protein denaturation inhibition (IC₅₀ = 0.4920 mg/mL). HPLC profiling revealed key anti-inflammatory phytoconstituents such as quercetin, kaempferol, lupeol, betulinic acid, methyl gallate, stigmasterol, and β-sitosterol variably distributed across the fractions. The findings demonstrate that fractions of Detarium microcarpum possess significant anti-inflammatory properties, likely attributable to their rich content of flavonoids, triterpenoids, sterols, and phenolic compounds. The results support the plant's traditional medicinal use and underscore its potential as a source of novel anti-inflammatory agents.