Effect of Different Solvents on Extraction Yield of Medicinal Plants

Abstract

The selection of an appropriate extraction solvent is a critical determinant of the quality and quantity of bioactive compounds recovered from medicinal plants. This study evaluated the effect of five solvents — water, 70% ethanol, methanol, ethyl acetate, and hexane — on the extraction yield and phytochemical profile of three widely used Indian medicinal plants: Azadirachta indica (neem), Ocimum sanctum (tulsi), and Curcuma longa (turmeric). Dried plant material was subjected to maceration at room temperature for 72 hours, followed by filtration, evaporation, and gravimetric yield determination. Phytochemical screening was performed to identify the classes of compounds present in each extract. Results demonstrated that methanolic extracts consistently yielded the highest extractable mass (ranging from 16.9% to 21.3%), while hexane extracts produced the lowest yields (4.7% to 7.8%). Polar solvents preferentially extracted phenolics, flavonoids, and alkaloids, whereas non-polar solvents were selective for terpenoids and fatty acids. Ethanol (70%) offered a practically advantageous balance of yield, safety, and broad-spectrum extraction. These findings provide evidence-based guidance for the optimisation of solvent selection in medicinal plant research and pharmaceutical applications.