Abstract
In order to get a clue to detect the change of protein structure by degradation, the fluorescence spectra of the aqeous ovalbumin solution were estimated in relation to the denaturation of protein by temperature, acid (pH), light illumination, urea and guanigin-hydrochloride, and the browning of protein with glucose and xylose.
The maximum increase of the fluorescence intensity of the ovalbumin was observed at the first stage of the thermal treatlnent (1-5 minutes) at 60°C. Its thermal increase of the fluorescence intensity was highest at Tyr residue spectrum. The fluorescence intensity of the ovalbumin was heigher between neutrality and alkaline region (pH 10) and lower at the acidic pH region, expecially, the maximum decrease of fluorescence intensity was observed at both pH 4.0 and pH 12. The increase of fluorescence of the ovalbumin were observed at Try residue at the first stage of ultra viollet rays illumination in the presence of riboflavin, and then its fluorescence intensity was remarkably decreased with illumination time.
The maximum decrease of the fluorescence intensity of ovalbumin with urea (8M) and guanidinhydrochloride (0.4M) was observed at Tyr and Try residue. The quenching effect of fluorescence intensity by guanidin-hydrochloride were greater than that of urea.
The maximum increase of the fluorescence of the ovalbumin with glucose and xylose was observed at the first stage of the browning reaction (4 days) and then diminished accompanying elevation the browning of the protein.
