Cyanide-induced alterations to the biophysical conformations of the isolated fish liver

The purpose of this study is to examine the applicability of an infared spe ctroscopic methodology for the study of an environmental problem. The effec t of cyanide concentrations on the biophysical conformation of the fish liv er homogenate was determined by using an attenuated total reflectance (ATR) /Fourier transform infrared (FT-IR) microspectroscopy. Alive male model fis h, Tilapia Zillii, was used. The liver from fish was isolated and homogeniz ed in pH 8.0 Tris buffer solution. The results indicate that the IR peak in tensity increased markedly in the C-H stretching range (3000-2800 cm(-1)), ester C=O stretching of lipids (1743 cm(-1)) and carbohydrate bands (1195-9 50 cm(-1)), but decreased in the amide I at 1649 cm(-1) and the free asymme tric stretching band of phosphate at 1261 cm(-1) with the increase of KCN c oncentrations. The marked release of hepatic enzymes and glutathione into h omogenate induced by cyanide might account for the higher IR spectral peak intensity of fish liver tissue after treatment with KCN. The cyanide was al so found to induce the protein structure of fish liver homogenate from alph a -helical conformation to beta -conformation.