Details

Autor(en) / Beteiligte

• Mondal, Satyajit
• Ghosh, Soumen
• Moulik, Satya P.

Titel

Stability of curcumin in different solvent and solution media: UV–visible and steady-state fluorescence spectral study

Ist Teil von

• Journal of photochemistry and photobiology. B, Biology, 2016-05, Vol.158, p.212-218

Ort / Verlag

Switzerland: Elsevier B.V

Erscheinungsjahr

2016

Quelle

MEDLINE

Beschreibungen/Notizen

• In aqueous solution, curcumin is photodegradable (light sensitive), it is also self-degradable in the dark. In basic medium, the second process is enhanced. The dark process has been studied in water and also in a number of protic and aprotic solvents, and aqueous solutions of ionic liquids, pluronics, reverse micelles and salt. The kinetics of the process followed the first order rate law; a comparative as well as individual assessment of which has been made. The kinetics of curcumin self-degradation has been found to be fairly dependent on salt (NaCl) concentration. Curcumin molecules in solution may remain in the enol or keto–enol form. From the visible spectral analysis, an estimate of the proportions of these forms in aqueous ethanol medium has been made. The temperature effect on the visible and fluorescence spectra of curcumin has been also studied. The steady state fluorescence anisotropy of the photoactive curcumin has been evaluated in different solvent and solution media. The reversibility of the steady state fluorescence anisotropy of curcumin on heating and cooling conditions has been examined. The results herein presented are new and ought to be useful as the study of physicochemistry of curcumin has been gaining importance in the light of its biological importance. •Curcumin stability in various solvent and solution media was studied.•Keto–enol forms of curcumin in ethanol–water medium were estimated.•UV–visible and fluorescence methods were employed to investigate the systems.•Fluorescence anisotropy measurements were taken in different solution environments.•Degradation kinetic in the solvent and salt media was examined.