Quercetin oxidation by horseradish peroxidase: the effect of UV-B irradiation
نویسندگان
چکیده
Horseradish peroxidase (HRP), a highly investigated member of the peroxidase family, has been known − among many other biological activities − to catalyze the oxidation of flavonoids and phenolic substrates overall, quercetin among them. On the other hand, quercetin is very well known for its expressed antioxidant activities, which in the case of UV external radiation can be expressed partly in a preventive manner: quercetin is an excellent UV-absorber. Therefore, the aim of this investigation was to study quercetin oxidation by HRP in phosphate buffer, under conditions of UV-stress, i.e. continuous, prolonged UV-B irradiation. The results show that while UV-B irradiation had definitely affected the activity of HRP, and the overal rate of quercetin oxidation by HRP, it had probably very little effect on it for longer UV-B-irradiation periods (>30 min).
منابع مشابه
Kinetics of enzymatic modification of quercetin with cysteine by horseradish peroxidase.
The kinetic mechanism of enzymatic modification of flavonol quercetin with L-cysteine by horseradish peroxidase (HRP) was studied. Reaction of modification of quercetin was followed by recording spectral changes over time at 380 nm. All reactions were performed in 100 mM phosphate buffer pH, 6.0 at 20 degrees C. Kinetic parameters were determined from graphics of linear Michaelis-Menten equatio...
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