DEPRESSION-RELEVANT OXIDATIVE STRESS MODULATION BY CLITORIA TERNATEA FLOWER ETHANOLIC EXTRACT: ANTIOXIDANT CAPACITY AND H₂O₂-INDUCED NEURONAL INJURY RESCUE IN SH-SY5Y CELLS

Abstract

Major depressive disorder is increasingly understood as a systems-level disorder in which oxidative stress, mitochondrial dysfunction, neuroinflammation, and impaired neuroplasticity interact to drive neuronal vulnerability. In this depression-relevant framework, we evaluated whether Clitoria ternatea flower ethanolic extract shows chemistry supported antioxidant capacity and functional rescue against oxidative neuronal injury. The extract was prepared by 70% ethanolic maceration and characterized by physicochemical parameters (pH, specific gravity, alcoholic content, TDS), UV–Vis spectral profiling (λmax 312 nm), TLC fingerprinting (Rf 0.71, 0.59, 0.39, 0.32), qualitative phytochemical screening, GC–MS metabolite annotation, and FTIR functional group assignment. Antioxidant capacity was quantified using DPPH and ABTS radical scavenging assays and FRAP reducing power, using ascorbic acid as a reference. Neuronal protection was functionally validated in SH-SY5Y cells exposed to an H₂O₂ injury condition (CTC₅₀), followed by post-injury treatment with graded extract concentrations and MTT-based viability quantification. GC–MS highlighted phytosterols (β-sitosterol, stigmasterol) and fatty acids (palmitic acid, linoleic acid), while FTIR supported polyphenol- and lipid-associated functional groups. The extract showed strong DPPH activity, moderate ABTS activity, high reducing power in FRAP, and a protective low-dose window that improved viability under oxidative challenge, supporting oxidative stress modulation relevant to depression biology.