Extraction, Isolation, and in Vitro Evaluation of Quercetin from Broccoli (Brassica Oleracea) for Metabolic Disorder Management

Abstract

Metabolic disorders such as diabetes and obesity are increasingly prevalent and pose significant global health challenges. Natural flavonoids like quercetin have shown promising therapeutic effects due to their antioxidant and enzyme inhibitory properties. In this study, quercetin was extracted and isolated from Brassica oleracea (broccoli) using methanolic maceration followed by column chromatography. The presence of quercetin was confirmed by thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) compared with a standard. The isolated compound was evaluated for in vitro antioxidant activity using the DPPH radical scavenging assay and for antidiabetic potential through α-amylase inhibition. Quercetin exhibited strong antioxidant activity with an IC₅₀ value of 38.5 µg/mL and demonstrated 68.7% α-amylase inhibition at 100 µg/mL. These findings confirm the dual therapeutic potential of broccoli-derived quercetin in managing oxidative stress and regulating carbohydrate metabolism. The study supports the role of dietary flavonoids as promising natural agents for metabolic disorder management and encourages further in vivo and clinical evaluation.