Flavonoid Content and Antioxidant Activity of Moringa oleifera Leaf Extract by UV–Vis and TLC

Abstract

Moringa oleifera leaves are widely recognised as a promising source of polyphenolic constituents, particularly flavonoids, that may contribute to antioxidant activity relevant to functional-food and herbal standardisation. This study aimed to evaluate extraction yield, perform flavonoid-oriented screening, quantify total flavonoid content (TFC), and assess antioxidant capacity of an ethanolic M. oleifera leaf extract using thin-layer chromatography (TLC) and UV–Vis spectrophotometry. Dried leaf powder was extracted by maceration, and the extract yield was determined gravimetrically. TLC profiling was conducted on silica gel plates using an appropriate solvent system, followed by UV observation and derivatisation to visualise flavonoid-like bands; TLC–DPPH spraying was applied for rapid localisation of antioxidant-active zones. TFC was quantified using the aluminium chloride colorimetric method and expressed as quercetin equivalents, while antioxidant activity was measured by the DPPH radical scavenging assay and expressed as IC₅₀. The extract exhibited measurable flavonoid-related chromatographic responses and produced antioxidant-active bands on TLC after DPPH treatment. Quantitatively, the extract demonstrated appreciable total flavonoid content and showed strong DPPH scavenging activity, indicating that M. oleifera leaves may serve as a feasible botanical raw material for standardised antioxidant preparations. Further work incorporating replicate-based precision metrics and confirmatory compound identification is warranted to strengthen analytical robustness and compound attribution.