Molecular Mechanism of Interaction of Curcumin with BSA, Surfactants and Live E. Coli Cell Membrane Revealed by Fluorescence Spectroscopy and Confocal Microscopy.

Clinical trials on the therapeutic effect of curcumin have proven to be highly effective against many diseases including cancer and Alzheimer's. However, the molecular mechanism of interaction of curcumin with protein and live cell membrane is poorly understood. Here, we report the mechanism of interaction of curcumin with bovine serum albumin (BSA) and live E. coli cell membrane in the presence of organized assemblies of sodium dodecyl sulfate (SDS) and cetrimonium bromide (CTAB) by fluorescence spectroscopy, laser-scanning confocal microscopy, and computation. Enhanced binding constant, blue-shifted emission spectra, and imaging of heterogeneous FRET on live bacteria cell membrane strongly indicate the complex formation of curcumin with strong hydrophobic interaction, which is further validated by computation. Finally, our results may shed light on the efficient strategy of applications of curcumin as a natural therapeutic lead in clinical trials against many life-threatening diseases.