Optimization of extraction conditions for the extraction of phenolic compounds from Moringa oleifera leaves

The aim of this study was to optimize the extraction conditions for the extraction of phenolic compounds from Moringa oleifera leaves using response surface methodology (RSM). A user- defined design was applied to determine the effects of extraction time (min), extraction temperature (degrees C) and ethanol concentration (%), on total phenolic content (TPC) from Moringa oleifera leaves dried by three methods (oven, sunlight and ambient air). The RSM was used to optimize the extraction conditions for the extraction of TPC of Moringa oleifera leaves. The optimum conditions that maximize the extraction of TPC were extraction time, 60 min; extraction temperature, 90 degrees C and % of methanol, 50 % (v/v). TPC extracted under these conditions were 12.28, 12.65 and 13.14 mg GAE/g DW for samples dried by different methods. Significant difference between drying methods was found (p < 0.001). Pair wise significant difference was found only between oven and ambient air drying methods (p < 0.001).