Anatomy study and evaluation ofAntioxidant Activity, Total Phenolics and Total Flavonoids Contents of Syrian Melilotus indicus L.

Abstract

The research aims to studying the anatomical structure and evaluation of antioxidant activity of ethanolic extracts of different plant parts (Leaves, Flowers, Fruits) of Syrian Melilotusindicus by studying the total content of phenols and flavonoids and its ability of inhibition free radicals by DPPH assay.

The phytochemical screening was performed by known color and precipitated reagents, the total phenols and flavonoids determined by Folin –Denis and aluminum chloride respectively.

The results of phytochemical screening showed exist of flavonoids, tannins and coumarins, but saponins and alkaloids are present but in small proportion, while anthraquinones are absent in the different parts of plant.

The results showed high and varied content of phenols and flavonoids in different plant parts, the highest total phenolic content was in leaves )10.05*± 0.23 mg GAE/g plant), then flowers (9.14 ± 0.21 mg GAE/g plant), then fruits(7.17± 0.63 mg GAE/g plant).

Also the highest total flavonoids content was in leaves (3.48*± 0.02 mg QE/g plant), then flowers (2.77 ± 0.07 mg QE/g plant), then fruits (2.60 ± 0.10 mg QE/g plant).

The results showed that the ability of the ethanolic extract of leaves and fruits to inhibit free radicals was similar 80.58%, while rising slightly in flowers 82.46%, consequently M. indicus would be promising source of antioxidant phytochemicals.

The anatomical study showed presence of the following anatomical characters as tricolporate pollen grains, anomocyte(Ranunculaceous type) stomata, triangular shape of the stem in transverse section, acute margin of leaf in transverse section, exist of collenchyma tissue under epidermis and over vascular bundle in leaf and stem, exist of inner secondary phloem in leaf and stem, palisade tissue continue under the upper epidermis in main rib of leaf.