Phytochemical Characterization, In-Vitro Antioxidant Activity, and Molecular Docking of Quercetin, Rutin and Apigenin

This study investigates the phytochemical characterization, in-vitro antioxidant activity, and molecular docking of natural flavonoids like Quercetin, Rutin, and Apigenin. FTIR analysis showed that each component possesses hydroxyl and carbonyl groups through the identification of specific functional groups that confirmed their structural nature. The results from phytochemical screening confirmed the presence of tannins and phenolics but also confirmed both flavonoids and flavanol glycosides and these findings were validated by fluorescence analysis. The total phenolic content analysis showed Quercetin possessed the greatest chemical content while Apigenin and Rutin followed with lower contents. The strongest antioxidant performance detected in the in-vitro assays using DPPH and nitric oxide radical scavenging (NORSA) and reducing power tests showed Quercetin to have IC50 values of 9.64 µg/ml and 6.71 µg/ml respectively. The antioxidant functions of both Rutin and Apigenin proved to be robust in the assessments. The binding ability of these flavonoids with Inducible Nitric Oxide Synthase (INOS) and xanthine oxidase proteins underwent molecular docking assessment to determine their binding affinity levels. The multiple hydroxyl groups in Quercetin enabled strong binding with proteins while Rutin and Apigenin followed behind. Keywords: Quercetin, Rutin, Apigenin, Antioxidant Activity, Molecular Docking