Deep eutectic solvents assisted green extraction and bioevaluation of phenolic compounds from Piper nigrum and...

Deep eutectic solvents (DESs) for extracting bioactives from Piper nigrum and Murraya koenigii, focusing on the effects of temperature and molar composition. Choline chloride-malonic acid DESs exhibited reduced viscosity with increasing temperature (1.78 to 1.276 mPa·s from 50 °C to 90 °C at 1:1.5 ratio), enhancing mass transfer. Thermal analysis confirmed low melting points and high stability, supporting their use in thermally assisted extraction. Optimal extraction occurred at 60 °C for P. nigrum (1:1.5) and 80 °C for M. koenigii (1:0.5). Acetone purification improved compound purity without major yield loss. Piperine and mahanimbine levels reached 10.34 % and 12 % w/w, respectively. Although DES extracts showed slightly lower lipid digestion inhibition than raw powders, their biocompatibility, low cytotoxicity, and potential to enhance bioavailability highlight their promise in sustainable functional food applications.