Interaction of Monoterpene Aldehydes of Iranian saffron with the DNA

This study has been carried out to investigate the interaction of two important components of monoterpene aldehydes family (picrocrocin and safranal) oflranian saffron with the DNA as a possible molecular mechanism for saffron's anti-cancer effect. Picrocrocin and safranal were extracted and purified from Iranian saffron.The DNA purification from the calf thymus was also performed. Then the interaction of the mentioned components of the saffron with the DNA was investigated in the tris buffer (0.05 M, pH 7.4 at 25° C) with various techniques.Results and disseusion: The absorption spectrum of the DNA was changed in the presence of picocrocin or safranal due to the complex formation. The increment in the absorption of the DNA at 260 nm was due to the DNA conformational changes after the complex formation. The DNA- safranal complex had also an additional peak at 315 nm. The fluorescence emission of the DNA-ethidium bromide complex was quenched by picrocrocin and safranal. The schatchard analysis of the quenching plots showed a noncompeptitive behavior. It means that picrocrocin or safranal bound to the DNA non-intercalatively may be through the DNA minor groove. The LlG (H20) as the best parameter for the stability of macromolecules was determined for the DNA in the presence of picrocrocin and safranal using the dodecyl trimethylammonium bromide (DTAB) as a denaturant. The results indicated that the DNA denaturation by the DTAB was accelerated with the both ligands, because the G (H2O) were decreased. This is the most important reason for the DNA destablization after the complex formation.