Study On The Extraction Of Turmeric And Purification Of Curcuminoids

Turmeric(Curcuma longa L) is a plant in the Zingiberaceae family and the main ingredient of curry. It has been widely applied as a coloring and flavoring agent, and it is also consumed as a food additive in curries and used to enhance storage, preservation, and palatability of food. Furthermore, it has long been used traditionally as an herbal medicine for treating a variety of inflammatory conditions such as coryza, cough, diabetic wounds, hepatitis, and other diseases. The major bioactive compounds in turmeric are three different curcuminoids:curcumin, demethoxycurcumin (DCM), and bisdemethoxycurcumin (BDCM). Curcuminoids have several biological activities, such as an antioxidant, antiprotozoal, antimicrobial, antitumor, anti-inflammatory, and anticancer and so on.Firstly, supercritical CO2 extraction was used to separate turmeric oil from Turmeric. Effects of pressure, temperature, extraction time, flow rate of CO2 and particle size on the yield of turmeric oil was studied systematically. In addition, solvent extraction with petroleum ether was also used to extract turmeric oil from Turmeric. Based on the single factor experiment design, four factors and three levels orthogonal experiments were further used to optimize extraction processes, including extraction time, solvent ratio, particle size, extraction temperature. The results indicated that the 5.82% yield of turmeric oil was observed with solvent extraction, and significantly higher than that of supercritical CO2 extraction.Secondly, Response surface methodology (RSM) was used to optimize the extraction conditions of curcuminoids. The effect of extraction time, extraction temperature, ethanol concentration, and the ratio of solid-liquid on the yield of curcuminoids was investigated systematically with RSM design. ANOVA results indicated that the regression model can reflect well with the relationship between the yields of curcuminoids and extraction time, extraction temperature, ethanol concentration and the ratio of solid-liquid. The yield can reach as high as up to 4.71% of curcuminoids at temperature of 80℃, extraction time of 2.5 h, ethanol volume of 88% and ratio of solid-liquid at 1:23. The relative error of predicted and measured values of the regression model was 1.2%, and the regression equation fit well with the actual situation.Thirdly, Turmeric was further purificated by macroporous resin. This paper selected four resin (S-8, AB-8, D101 and DM301) and their adsorption/desorption ability will be cooperated. The results showed that the polar S-8 resin possessed the best absorption and desorption capacity. The static equilibrium adsorption data fitted better to the Freundlich equation, and the adsorption kinetic followed the pseudo-second order model. An optimized process of CM, DCM, and BDCM from turmeric were carried out by dynamic adsorption/desorption experiments with the column packed with S-8 resin.This paper explores the influence of flow rate on the adsorption capacity, the adsorption effect of different concentrations of liquid material on the dynamic adsorption, dynamic leakage curve and desorption curves.Finally, the modified polyamide resin was be used to isolated three components from curcumin. Static adsorption experiments investigated the effect of temperature and the value of the sample solution pH, and fitting the Freundlich adsorption model of modified polyamide resin. Modified polyamide resin adsorption curcumin, DCM and BDCM are multi-molecular layer. Dynamic of resin adsorption and desorption experiments to investigate the leak curve and gradient elution to obtain optimum separation conditions parameters. Three target components (curcumin, DCM and BDCM) through the enrichment and processing segment on modified polyamide resin, the purity can reach 99.28%,98.8%, and 98.2%, recoveries were 76.2%,73.1% and 68.0%In this paper, a series of separation methods of curcuminoids from Turmeric were investigated and the results not only provide technical support and guidance of the theory, but also have a strong practical value and urgent market demand. The successful implementation of the project, promote research and development in the natural field of fine chemicals products.