Abstract:
Plant polyphenols and flavonoids are of great interest for the development of nutraceuticals targeting the management of chronic disease. Composition of the extraction solvent is an important determinant for the preparation of polyphenol rich plant extracts. Pure organic solvents, aqueous-organic solvents and distilled H2O are commonly used for the extraction of plant polyphenols and flavonoids. H2O and ethanol are considered as solvents suitable for human consumption hence commonly used in extraction of bioactive compounds. This study aims to investigate the effect of water: ethanol ratio on extraction yield, total polyphenol content (TPC) and total flavonoid content (TFC) of selected medicinal plants using in vitro colorimetric assays. Leaves of Coccinia grandis (L.) Voigt (Kovakka), Gymnema sylvestre (Retz.) Schult (Masbedda), Murraya koegnii (L.) Spreng. (Karapincha), Costus speciosus (Koenig) Smith.
