[01] Martina Bancirova, Palacky University, Department of Medical Chemistry and Biochemistry, Hnevotinska 3, 77515 Olomouc, Czech Republic.

The autooxidation of quercetin under laboratory conditions was studied by changes of the absorption spectra during seven hours after dilution. The influence of the primal solvent was observed. In case of quercetin dissolved in ethanol, there can be observed the decrease in λmax at 380 nm, in case of quercetin dissolved in methanol; there can be observed the decrease in λmax at 385 nm, in case of quercetin dissolved in DMSO, there can be observed the decrease in λmax at 390 nm. There is also the appearance of new peak at 330 nm for quercetin dissolved in all solvents.

Quercetin, Solvent, Spectrophotometry

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