In vitro assessment of the antioxidant and immunomodulatory potential of Ageratum conyzoides linn. leaf extract

AbstractMedicinal plants have been vital sources of bioactive compounds for traditional medicine and modern pharmaceutical development. Ageratum conyzoides Linn., a widely distributed herbaceous weed, has been traditionally used to treat various ailments, including infections, inflammation, and wounds. This study evaluated the antioxidant and immunomodulatory potential of Ageratum conyzoides Linn. The leaves were collected and processed to obtain a 50% hydromethanolic extract (ACE), which was analyzed for phytochemical composition and assessed for antioxidant properties through various in vitro assays. Cytotoxicity was evaluated by determining the Maximum Non-Cytotoxic Dose (MNCD) using the MTT assay. Immunomodulatory potential was assessed via the Lymphocyte Proliferation Assay (LPA). Qualitative phytochemical analysis confirmed the presence of alkaloids, phenolics, flavonoids, tannins, and saponins, while quantitative analysis revealed significant levels of total phenolics (111.371± 1.697 mg GAE/g) and flavonoids (69.394 ± 0.757 mg RE/g). The extract exhibited strong antioxidant activity in DPPH radical scavenging, superoxide anion radical scavenging, hydroxyl radical scavenging, and metal ion chelation, demonstrating concentration-dependent effects. ACE also showed substantial ferrous reducing antioxidant power (107.31 ± 1.060 mg AAE/g) and total antioxidant capacity (297.94 ± 1.923 mg AAE/g). Immunomodulatory studies revealed that ACE at its MNCD (250 µg/mL) significantly enhanced lymphocyte proliferation, with particularly notable effects on B cells and T cells. These findings validate the traditional medicinal use of Ageratum conyzoides Linn. and highlight its potential as a natural source of antioxidants and immunomodulators. Future research should focus on isolating and characterizing the bioactive compounds responsible for these effects and exploring their molecular mechanisms of action.