The effect of extraction parameters on the total polyphenol content and the antioxidant activity of aqueous Moringa oleifera leaf extract

Abstract

Currently, thanks to the diversity of beneficial bioactive substances in the composition of Moringa oleifera leaves, increasing attention has been focused on Moringa oleifera (Moringa oleifera Lam). In this research, the effects of Moringa oleifera extraction conditions on total polyphenol contents and antioxidant activities of the leaf extract were investigated. The optimal conditions for aqueous extraction were selected, including the material/water ratio of 1/30 g/mL, the extraction temperature of 80°C, the extraction time of 30 mins. The total phenolic content reached the highest value of 23.9 mg Gallic acid equivalent/g dry leaf. The antioxidant scavenging activities of aqueous leaf extracts ranged from 16 to 30 mg Trolox equivalent/g dry leaf. Overall, with its high antioxidant capacity, the Moringa oleifera aqueous leaf extract shows not only potential values in food, medicine, and cosmetics disciplines but also economic significance.