IDENTIFICATION OF HEMORPHINS FROM BOVINE HEMOGLOBIN HYDROLYSATE - APPLICATION OF UV 2ND-ORDER DERIVATIVE SPECTROSCOPY

Aromatic amino acids have very informative second order derivative spectra. Whereas they exhibit overlapping maxima between 250 and 300nm in the zero order spectra, thin minima are obtained in their second order derivative spectra. This feature allowed to develop a method to identify aromatic amino acids, but also to calculate the ratio between these amino acids in peptides and proteins. This method has been used successfully for the detection of hemorphins in a peptic bovine hemoglobin hydrolysate. The constant ratios between aromatic amino acids are an important characteristic of lots of bioactive peptides; the advantage of this spectral method is to be non-destructive for the identification of these amino acids espacially for tryptophan.