Evaluation the effect of different solvents and extraction method on phytochemical content and antioxidant activity of Moringa oleifera leaf extract

Plants are rich source of phenolic compounds, which are the most important natural antioxidants. The aim of this study was to investigate the effect of extraction methods and different solvents on extraction yield, total phenolic content (TPC), total flavonoid content (TFC) and free radicals scavenging activity of DPPH in Moringa oleifera leaf extract. For this, the leaves were grinding after dried followed by different extraction techniques like soaking, Soxhlet and ultrasound (Frequency: 70 kHz) using distilled water, acetone and methanol as solvent. TPC and TFC were measured using Folin–Ciocalteu method and colorimetric assay. Antioxidant activity of resulted extracts was measured using 2, 2-Diphenyl-1-picryl-hydrazyl (DPPH). The antioxidant activity of the extracts was compared with ascorbic acid. The highest extraction efficiency was obtained in Soxhlet method use acetone as solvent (24.40±0.34%). Methanol in Soxhlet extraction method showed the highest effect on TPC (24.79±1.35 mg GAE/g dry sample) and TFC (81.14±1.45 mg QU/g dry sample). In all samples, increased DPPH free radical scavenging when increased concentration of the extracts. The highest radical scavenging was observed in methanol extracts obtained by Soxhlet (IC50=49.97±0.65). Finally, it could be concluded that, methanol was the best solvent and Soxhlet was the best method for extraction of phenolic and flavonoid compounds in in the leaves of Moringa oleifera.