Optimization of the extraction of antioxidants from Moringa leaves: A comparative study between ultrasound-and ultra-homogenizer-assisted extractions

摘要

This work investigated the effect of the solvent composition and solid/solvent ratioon the extraction of antioxidants from Moringa oleifera Lam leaves using experimentaldesign and compared the efficiency between the ultrasound-(UAE) and ultra-homogenizer(HAE)-assistedextractions. The phytochemical composition of theoptimized extracts was investigated by ultra-high-performanceliquid chromatographycoupled with a high-resolutionmass spectrometer (UHPLC-QTOF-MS/MS). Theexperimental results adequately fitted to quadratic models as indicated by the coefficientof determination (0.71-0.97),low standard errors of estimate, and lack of fit>0.05. The optimum conditions of extraction for both methods were identified as4:200 solid:solvent (m/v) and a 1:1 water:ethanol (v/v) ratio. Thirty compounds wereidentified by UHPLC-QTOF-MS/MS, among which quercetin, rutin, kaempferol, alkaloids,and lignins. Both techniques studied were efficient in extracting antioxidantsfrom Moringa leaves. The HAE equipment has a longer extraction time but is moreaccessible than the UAE equipment.