K.Senthil,  P.M.Andavan

ABSTRACT

Curcumin is a non toxic, a dietary natural polyphenol known for its potent anti-inflammatory, antioxidant, antimutagenic and anticarcinogenic effects. The interaction of curcumin Complex(Curcumin and metal ions) with DNA is widely used in clinical treatment of a variety of neoplastic diseases, but its therapeutic effects is not fully understood. We here report the binding mechanism and structural properties of curcumin with DNA considered as a therapeutic target. The interaction of DNA with curcumin is investigated in aqueous solution at physiological pH with durg/DNA molar ratios of r=1:40, 1:20, 1:10, 1:5 and 1:2. Fourier Transform Infrared(FT-IR) and UV-absorption spectroscopy are used to determine the secondary structure of drug and DNA, drug binding sites, binding constant, as well as the structural variations of curcumin-DNA complexes in aqueous solution. Our spectroscopic result showed that interaction occurred mainly through G-C ,A-T base pairs and major interaction with phosphate groups with overall binding constant of K= 2.95×105 M-1. Curcumin complexes maybe induced biopolymer conformational changes with DNA in the presence of metal ions. Keywords: DNA, Curcumin; FT-IR spectroscopy.