Journal of Agricultural and Food Chemistry
Article
reduction of dopaquinone to dopa, which can then act as the
activator. Lack of such an effect in the case of kaempferol has
to be attributed to its strong inhibition of the monophenolase
activity. Under conditions applied in our experiments the
reaction rates were so small, that the amount of dopa formed
during the measurement period was not sufficient to eliminate
the lag period, which may be considered as extended indefinitely
(to the end of the measurement period).
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Figure 3A and F). We have previously described this pheno-
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ASSOCIATED CONTENT
* Supporting Information
■
S
The Supporting Information is available free of charge on the
Figures presenting additional experiments and/or data:
spectra recorded during oxidation of kaempferol by large
amount of tyrosinase (Figure S1), complete sets of spectra
recorded during reactions of flavonoids with o-quinones
(Figure S2), and spectra showing the stability of 4-tert-
butyl-o-benzoquinone and 4-methyl-o-benzoquinone
(17) Zheng, Z.-P.; Cheng, K.-W.; Chao, J.; Wu, J.; Wang, M.
Tyrosinase inhibitors from paper mulberry (Broussonetia papyrifera).
Food Chem. 2008, 106, 529−535.
AUTHOR INFORMATION
Corresponding Author
(18) Lin, L.; Dong, Y.; Zhao, H.; Wen, L.; Yang, B.; Zhao, M.
Comparative evaluation of rosmarinic acid, methyl rosmarinate and
pedalitin isolated from Rabdosia serra (MAXIM.) HARA as inhibitors of
tyrosinase and α-glucosidase. Food Chem. 2011, 129, 884−889.
(19) Bouzaiene, N. N.; Chaabane, F.; Sassi, A.; Chekir-Ghedira, L.;
Ghedira, K. Effect of apigenin-7-glucoside, genkwanin and naringenin
on tyrosinase activity and melanin synthesis in B16F10 melanoma cells.
Life Sci. 2016, 144, 80−85.
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*Phone: +48 77 452 7122; Fax: +48 77 452 7101; E-mail:
Funding
This work was supported by statutory funds from the Polish
Ministry of Science and Higher Education.
(20) Ko, R. K.; Kim, G. O.; Hyun, C. G.; Jung, D. S.; Lee, N. H.
Compounds with tyrosinase inhibition, elastase inhibition and DPPH
radical scavenging activities from the branches of Distylium racemosum
Sieb. et Zucc. Phytother. Res. 2011, 25, 1451−1456.
(21) Liang, X.; Wu, Y. P.; Qiu, J. H.; Zhong, K.; Gao, H. A potent
antibrowning agent from pine needles of Cedrus deodara: 2R,3R-
dihydromyricetin. J. Food Sci. 2014, 79, C1643−1648.
Notes
The authors declare no competing financial interest.
ABBREVIATIONS USED
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DPPH·,2,2-diphenyl-1-picrylhydrazyl radical; ABTS+·,2,2′-azino-
bis(3-ethylbenzothiazoline-6-sulfonic acid) radical
J
J. Agric. Food Chem. XXXX, XXX, XXX−XXX