The optimization and comparison of different extraction approaches (ultrasound and maceration) on chemical composition of Elaeagnus angustifolial L. extract

Elaeagnus angustifolia L. is regarded as one of the most important medicinal and nutritious plants since it contains flavonoid, sitosterols, cardiac glycosides and terpenoids compounds. The purpose of this study was to investigating the effects of extraction conditions on phenol and flavonoid content from methanolic extracts ofElaeagnus angustifolia (peel, pulp and seed) through ultrasound and maceration methods. The response surface methodology (RSM) was used to optimize the extraction conditions for highest extraction rates of phenolic and flavonoid compounds. Box Behnken design was employed to investigate the effects of the three independent variables including solvent to sample ratio (20-50 ml/g), temperature (30-60°C) and extraction time (5-35 min) on the dependent variables (extraction yield, phenolic and flavonoid contents). The total phenolic content was measured using the Folin-Ciocalteu’s reagent. The total flavonoid content was assessed by the colorimetric method based on Aluminum Chloride which underwent some changes. The variance coefficients indicated that the effect of ultrasound temperature on the extraction yield was more influential than the other ones (p