Differential extraction of phytochemicals from the multipurpose tree, Moringa oleifera, using green extraction solvents

Moringa oleifera is a tree plant with important bioactive compounds that confer its pharmacological properties. These compounds have been commonly extracted from the leaves using general methanol-based procedures. Organic solvents used for extraction purposes have negative impacts on the environment and human health. Green technologies are emerging as preferred choices for extraction as it encourages practices that are environmentally friendly and pose less or no harm to humans. In this study, the extraction-ability of pressurized hot water, aqueous two-phase (20% ammonium sulfate and ethanol) and the natural deep eutectic solvent (choline chloride and citric acid) was demonstrated on dried M. oleifera leaves. Each extract was analyzed on a reverse phase ultra-high performance liquid chromatography high definition quadrupole time-of-flight mass spectrometry instrument. Bioactive compounds, belonging to the class of polyphenolics (hydroxycinnamic acid and flavonoids) and glucosinolates, were annotated in these leaf tissue extracts. In the pharmaceutical industry where extraction is one of the most crucial steps for new drug discovery, this study will provide a premise illustrating the extractability of phytochemicals with the aid of eco-friendly solvents.