An Investigation on intermolecular interaction between Bis(indolyl)methane and HSA and BSA using multi technique methods

Bis(indolyl)methane (BIM) as one of the main active components of anticancer and antibacterial drugs is applied in medicinal and extensive area of chemistry. In this research, interaction of human and bovine serum albumins as drug carriers with BIM was investigated using spectroscopy methods and molecular modeling study. The fluorescence quenching measurements at the range of 293-310K revealed that the quenching mechanisms for human and bovine serum albumins are static and dynamic processes, respectively. The results of quenching study were used to calculate thermodynamic parameters which indicated that the binding process occurs spontaneously and demonstrated that human and bovine serum albumins provide very good binding via hydrogen bonds, van der Waals forces, and hydrophobic interactions. Forster energy transfer measurements, synchronous fluorescence spectroscopy, and docking study showed BIM binds to the Trp residues of human and bovine serum albumin molecules in short distances. Docking study showed that BIM molecule has two hydrogen bonds and several van der Waals contacts with human and bovine serum albumins. Results of FT-IR and CD spectroscopy demonstrated that serum albumins interact with BIM molecule mainly via hydrophobic and hydrophilic interactions and the secondary structure of serum albumins are changed.