Column Chromatography purification and evaluation of In Vitro Antioxidant Activity of Flavonoid from Some Selected Citrus Fruit Peels

It is a long and tedious process to isolate pure, pharmacologically active constituents from plants Flavonoids are pharmacologically active constituents cannot be synthesized by humans. This study was aimed to partially purify favonoids from some selected citrus fruit peels, to determine flavonoid contents and to evaluate in vitro antioxidant activity of the extracts. Purification was carried out using silica gel column chromatographic techniques. Flavonoid contents were determined by colorimetric aluminum chloride. In vitro antioxidant properties were investigated by DPPH and Nitric Oxide radical scavenging, and reducing power activity assay. Lemon peel’s extract showed significantly the highest total flavonoid contents (9.57 ± 0.38). Orange peel’s extract showed the significantly the lowest flavonoid content (3.7 ± 0.45). Lemon peel’s extract showed the highest DPPH radical scavenging (75.60 ± 2.38%) at 100 µg/ml. Orange peel’s extract showed the highest Nitric oxide Scavenging(88.32± 1.37%) at 1000 µg/ml and reducing power (0.45 ± 0.5%) at 800µg/ml. A strong correlation between citrus fruit peel extracts and antioxidant activity was failed to demonstrate by regression analysis. In Conclusion, antioxidant activity of citrus fruit peels’ flavonoid was confirmed and antioxidant potential of the peels were not depend on the concentration of flavonoids.