A Novel and Simple Approach for Extraction and Isolation of Curcuminoids from Turmeric Rhizomes

Turmeric (Curcuma longa L. Family: Zingiberaceae) is a widely cultivated spice in India and other Asian countries. Curcumin is the main coloring substance in Curcuma longa and two related compounds, demethoxycurcumin and bisdemethoxycurcumin are altogether known as curcuminoids. Turmeric is rich in curcuminoids, and recognized for their broad spectrum of biological activities. During isolation and purification of curcuminoids from oleo resin, the volatile oil present turmeric solubilizes curcumin creating problem in recrystallization process. To eliminate the interference of volatile oil and resolve the problem recrystallization, the present research work was undertaken. Various organic solvents and their combinations were tried for selective recrystallization of curcuminoids. Mixture of hot isopropyl alcohol: hexane (1:1.5) was found to be the best recrystallization solvent for purification of curcuminoids. The identity of curcuminoids was further confirmed by thin layer chromatography (TLC) and Fourier Transform Infra-Red spectroscopy (FTIR). The total curcumin content of crude curcuminoid powder was found to be 76.82% W/W whereas in recrystallized powder the purity was increased to 99.45% W/W.