Central composite design based statistical modelling of curcuminoids extraction from Curcuma zedoaria using choline chloride based Natural Deep Eutectic Solvent (NADES)

Abstract Ionic type of Natural Deep Eutectic Solvents (NADES) consisted of choline chloride and organic acids, i.e., choline chloride-malic acid (CCMA) and choline chloride-citric acid (CCCA), known as the most suitable liquefied solvent for curcuminoids extraction from Curcuma zedoaria . A laboratory-scale extraction of curcuminoids from C. zedoaria successfully conducted; indicated that solvent per feed ratio (S/F) and extraction time are the two important variables for yielding a high extraction rate of curcuminoids. Therefore, a central composite based design is used to optimize the extraction parameters such as S/F (3/10, 5/10, 7/10), time extraction (18, 20, and 22 h), and stirring speed (200, 250, and 300 rpm) at 500 mL capacity. Stirring speed is the most influential parameter among the studied parameters. However, due to the low bulk density of C. zedoaria powder, a homogenous mixture of C. zedoaria in the extraction tank was barely achieved; hence a low yield of curcuminoids is obtained.