Quercetin mutagenicity

FACTORS WHICH FACILITATE INACTIVATION OF QUERCETIN MUTAGENICITY... 

Several factors expected to modify quercetin mutagenicity were, therefore, studied to establish optimal conditions for inactivating or suppressing the mutagenic potential of quercetin. 

Exposure of quercetin to buffers in an oxygen atmosphere had no observable effect on quercetin mutagenicity in the pH range 2 to 5. The transition point for the pH-oxygen inactivation appears to be near pH 6.5, since the number of revertants at this pH was about 440 compared to about 1000 at the lower pH values. Complete inactivation, where the number of revertants equals that observed with buffer controls, took place at pH values above 8. 

Table 4. Effect of temperature on quercetin mutagenicity (exposure for 3 hours at pH 7.5 and 9.0 in the presence of oxygen).

These results strikingly demonstrate the minor influence of temperature compared to the major effect of pH on quercetin mutagenicity. 

FACTORS WITH FACILITAE QUERCETIN MUTAGENICITY Table 6. Effect of time on the mutagenicity of quercetin at pH 7.5 and 537 9.O. . 

Limited studies showed that the following enzymes had no or only minor effects on quercetin mutagenicity under conditions similar to those used for tyrosinase (1 100 weight ratio enzyme to quercetin 50% pH 7.5 buffer ethanol 37 C 2 hours) catalase, lipoxygenase, peroxidase, and superoxide dismutase. Additional studies are needed to define the ability of these oxidizing enzymes to modify flavonoids over a broader pH range. 

Table 7 shows that (a) copper, ferrous and ferric sulfates have the ability to inactivate quercetin mutagenicity at pH 7, even in a... 

Reversibility of copper sulfate and ferrous sulface catalyzed inactivation of quercetin mutagenicity . 

Table 8. Effect of metal salts on quercetin mutagenicity. ...

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