Heavy Metals Chelating Ability and Antioxidant Activity of Phragmites australis Stems Extracts

In this study, the ability of hexane (HSE), chloroform (CSE), ethyl acetate (EASE) and methanolic (MSE) stems extracts from Phragmites australis or EDTA (as standard) to chelate iron using ferrozine method or zinc and copper using the murexide method is carried out in vitro. When the increased volumes of the HSE studied were taken from a stock solution of a fixed concentration 1 mg/ml at 25-175 mu l for the iron and zinc chelating assay, 1-7 mg/ml for the copper chelating assay gave a significant (p <= 0.01) activity. The obtained results showed that the HSE have the highest capacity to chelate ferrous ions below the EDTA (standard chelator) with absorbance arrive to the lesser extent 0.24 +/- 0.005, 0.04 +/- 0.013 which expresses 86% and 97% (compared to the control) of inhibition, respectively. For the murexide chelation, the results obtained also showed that the HSE and EDTA have a good (p <= 0.01) chelating dose dependent effect towards zinc and copper ions with increased absorbance 0.45 +/- 0.02 and 0.42 +/- 0.02 with 54% and 56% of inhibition, respectively, for the zinc chelation and 0.66 +/- 0.03, 0.13 +/- 0.005 represent 44% and 88% for copper chelation. In contrast to the antioxidant capacity, the extract of hexane, ethyl acetate, chloroform and methanol from leaves, stems and roots of the Phragmites australis plant have a very low scavenger effect to the radical DPPH where the maximum inhibition is approximately 13.79%, obtained with the maximum volume. Finally, the HPLC analysis of effective extract (HSE) confirmed the presence of oxalic, citric, malic, succinic, fumaric, formic, acetic, propionic and butyric or iso butyric acid.