Systematic Characterization of Antioxidant Shielding Capacity Against Oxidative Stress of Aerial Part Extracts of...

Oxidative stress is a biological imbalance that contributes to cellular damage and is a major driver of aging and age-related disorders, prompting the search for natural antioxidant agents. Our study is a phytochemical, electrochemical, and biological characterization of the antioxidant potential of aqueous extracts from aerial parts of A. occidentale-leaves, bark, fruit, and cashew nuts-traditionally used in folklore medicine. Extracts were analyzed using FT-IR spectroscopy, GC × GC-TOFMS, polyphenol quantification, and antioxidant capacity assays (ABTS, FRAP, DPPH). Biological activity was tested in different mice and human cell lines (SH-SY5Y, MEF, ARPE-19, and HLECs). Aqueous extracts from the leaves and bark of A. occidentale exhibited significantly higher antioxidant activity compared to those from the fruit and cashew nut. These extracts showed elevated polyphenol content and strong performance in antioxidant capacity assays. In vitro, leaf and bark extracts enhanced cell viability under H₂O₂-induced oxidative stress, preserved mitochondrial membrane potential, and upregulated cytoprotective genes (HMOX1, NQO1, GCLC, and GCLM) in multiple cell lines. In contrast, fruit and nut extracts showed minimal antioxidant activity and no significant gene modulation. Our findings underscore the therapeutic potential of A. occidentale leaf and bark extracts as effective natural antioxidants and support their further development as candidates for phytotherapeutic interventions.