Effect of extraction conditions on the bioactive compounds from Moringa oleifera (PKM 1) seeds and their identification using LC–MS

The objective of the present study was to optimise the conditions for extraction of bioactive compounds from drumstick (Moringa oleifera) seeds to determine their potential as a source of nutraceuticals. A central composite face centred design was applied to determine the effects of ethanol concentration (%), extraction temperature (°C), extraction time (min) and particle size (mm) on total phenolic content, total flavonoid content, total antioxidant activity, ferric reducing power and hydrogen peroxide scavenging activity. A second-order polynomial model was used for predicting the responses. The optimum extraction conditions were found to be ethanol concentration, 49.8 %, extraction temperature, 80 °C, extraction time, 45 min and particle size, 0.62 mm. LC–MS analysis under the optimum conditions led to the identification of 12 bioactive compounds. Major compounds were identified as 1H-pyrazol-4-yl methanol, 1-(2-methyl-5-nitro-1H-imidazol-1-yl)propan-2-ol, 1,4-naphthoquinone, luteolin-6-c-glucoside and hesperidin, which possess different biological activities.