Curcuminoids

The choice of the method of analysis depends on the question to address. Spectrophotometry is sufficient for total curcuminoid content determination in a turmeric extract. Separation techniques coupled to mass spectrometry detection and MALDl-TOF are highly sensitive techniques that are more adapted to the identification of metabolites in biological fluids such as urine or plasma. ... 

Sensitive Methods for Analysis of Curcuminoids and Their Metabolites... 

Yuan, K. et al., Application of capillary zone electrophoresis in the separation and determination of the curcuminoids in urine, J. Pharm. Biomed. Anal, 38, 133, 2005. 

Tonnesen, H.H. and Karlsen, J., Studies on curcumin and curcuminoids. VI. Kinetics of curcumin degradation in aqueous solution, Z. Lebensm. Unters. Forsch., 180, 402, 1985. 

He, X.G. et al, Liquid chromatography-electrospray mass spectrometric analysis of curcuminoids and sesquiterpenoids in turmeric Curcuma longa), J. Chromatogr. A, 818, 127, 1998. 

Taylor, S.J. and McDowell, I.J., Determination of the curcuminoid pigments in turmeric (Curcuma domestica Val) by reversed-phase high performance liquid chromatography, Chmmatographia, 34, 73, 1992. 

Lechtenberg, M. et al., Quantitative determination of curcuminoids in Curcuma rhizomes and rapid differentiation of Curcuma domestica Val. and Curcuma xanthor-rhiza Roxb. by capillary electrophoresis, Phytochem. Anal, 15, 152, 2004. 

Asai, A. and Miyazawa, T., Occurrence of administered curcuminoid as glucuronide and glucuronide/sulfate conjugates in rat plasma, Life Sci., 67, 2785, 2000. 

Jeong, G.S. et al.. Comparative effects of curcuminoids on endothelial heme oxygeanse-1 expression ortho-methoxy groups are essential to enhance heme oxygenase activity and protection, Exp. Molec. Med., 38, 393, 2006. 

Turmeric contains two main classes of compounds the curcuminoids responsible for the yellow color and the aroma compounds. The coloring principle of turmeric consists of three major phenolic derivatives curcumin, demethoxycurcumin, and bisdemethoxycurcumin. Commercially available products called curcumins contain curcumin (l,7-bis(4-hydroxy-methoxyphenyl)-l,6-heptadiene-3,5-dione) as the major component (about 77% of total curcuminoids). Some other minor phenohc compounds such as cyclocurcumin and calebin were also isolated from turmeric. See Figure 5.2.1. 

FIGURE 5.2.1 Chemical structures of curcuminoid pigments and some aroma compounds of turmeric. 

Antioxidant capacities of common individual curcuminoids were determined in vitro by phosphomolybdenum and linoleic acid peroxidation methods. Antioxidant capacities expressed as ascorbic acid equivalents (pmol/g) were 3099 for curcumin, 2833 for demethoxycurcumin, and 2677 for bisdemethoxycurcumin at concentrations of 50 ppm. The same order of antioxidant activity (curcumin > demethoxycurcumin > bisdemethoxycurcumin) was observed when compared with BHT (buty-lated hydroxyl toluene) in linoleic peroxidation tests. The antioxidant activity of curcumin in the presence of ethyl linoleate was demonstrated and six reaction products were identified and structurally characterized. The mechanism proposed for this activity consisted of an oxidative coupling reaction at the 3 position of the curcumin with the lipid and a subsequent intramolecular Diels-Alder reaction. ... 

Tpnnesen, H.H, Masson, M., and Loftsson, T., Studies on curcumin and curcuminoids. XXVII. Cyclodextrin complexation solubility, chemical an photochemical stability, Int. J. Pharm., 244, 127, 2002. 

Four different commercially available varieties of turmeric containing curcumin were isolated, separated by column chromatography, and identified by spectroscopy. The purity of the curcuminoids was analyzed by an improved HPLC method, performed on a Ci8 column using methanol, acetic acid, and acetonitrile and detection at 425 nm. The total percentages of curcuminoids in turmeric were between 2.34... 

Gupta, A.P., Gupta, M.M., Kumar, S., Simultaneous determination of curcuminoids in curcuma samples using high performance thin layer chromatography, J. Liq. Chromatogr. Rel. TechnoL, 22, 1561, 1999. 

Pathania, V., Improved HPTLC method for determination of curcuminoids from Curcuma longa, J. Liq.Chromatogr. Rel. TechnoL, 29, 877, 2006. 

Curcuminoids, yellow colorants, from turmeric (Curcuma)... 

Figure 13.5 Product ion spectra of curcuminoids (Nl HPLC ESI MS/MS). Product ion labels correspond to fragments depicted in Figure 13.6 (a) bisdemethoxycurcumin (b) demethox ycurcumin (c) curcumin. Reproduced from H. Jiang, A. Somogyl, N.E. Jacobsen, B.N. Timmermann and D.R. Gang. Rapid Commun. Mass Spectrom., 20, 1001 1012 (2006). By permission of John Wiley Sons, Ltd...

---