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. 2018 Dec;33(1):1048-1054.
doi: 10.1080/14756366.2018.1477776.

Kushenol A and 8-prenylkaempferol, tyrosinase inhibitors, derived from Sophora flavescens

Jang Hoon Kim  1 , In Sook Cho  2 , Yang Kang So  1 , Hyeong-Hwan Kim  2 , Young Ho Kim  3
Affiliations

Kushenol A and 8-prenylkaempferol, tyrosinase inhibitors, derived from Sophora flavescens

Jang Hoon Kim et al. J Enzyme Inhib Med Chem. 2018 Dec.

Abstract

Tyrosinase is known for an enzyme that plays a key role in producing the initial precursor of melanin biosynthesis. Inhibition of the catalytic reaction of this enzyme led to some advantage such as skin-whitening and anti-insect agents. To find a natural compound with inhibitory activity towards tyrosinase, the five flavonoids of kushenol A (1), 8-prenylkaempferol (2), kushenol C (3), formononetin (4) and 8-prenylnaringenin (5) were isolated by column chromatography from a 95% methanol extract of Sophora flavescens. The ability of these flavonoids to block the conversion of L-tyrosine to L-DOPA by tyrosinase was tested in vitro. Compounds 1 and 2 exhibited potent inhibitory activity, with IC50 values less than 10 µM. Furthermore, enzyme kinetics and molecular docking analysis revealed the formation of a binary encounter complex between compounds 1-4 and the enzyme. Also, all of the isolated compounds (1-5) were confirmed to possess antioxidant activity.

Keywords: Fabaceae; Sophora flavescens; antioxidant; molecular docking; tyrosinase inhibitor.

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Figures

Figure 1.
Figure 1.
Structures of isolated compounds 1–5 from S. flavescens.
Figure 2.
Figure 2.
(A) Inhibitory activity of compounds 1–4 on tyrosinase. (B–E) Linewever-Burk plots of tyrosinase inhibition by compounds 1–4, respectively. (F) Secondary re-plot of slope vs. [I].
Figure 3.
Figure 3.
(A–D) The green dotted line present hydrogen bond interactions between ligands 1–4 and receptor, respectively.
Figure 4.
Figure 4.
(A–D) The location of respective ligands 1–4 bound into receptor.
Figure 5.
Figure 5.
Effect of compounds 1–5 on intracellular ROS generation in H2O2-treated H2P2G cells (The results are presented as the means ± SDs of three replicates of on represent experiment. *p < .05 vs. negative group, #p < .05 vs. positive group).
See this image and copyright information in PMC

References

    1. He X, Fang J, Huang L, et al. . Sophora flavescens Ait.: traditional usage, phytochemistry and pharmacology of an important traditional Chinese medicine. J Ethnopharmacol 2015;172:10–29. - PubMed
    1. Zhang W, Liu X, Fan H, et al. . Separation and purification of alkaloids from Sophora flavescens Ait. by focused microwave-assisted aqueous two-phase extraction coupled with reversed micellar extraction. Ind Crops Prod 2016;86:231–8.
    1. Zhang Q, Yu J, Wang Y, Su W. Selective extraction of flavonoids from Sophora flavescens Ait. by mechanochemistry. Molecules 2016;21:989–1003. - PMC - PubMed
    1. Liu G, Dong J, Wang H, et al. . Characterization of alkaloids in Sophora flavescens Ait. by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry. J Pharm Biomed Anal Title 2011;54:1065–72. - PubMed
    1. Quang TH, Ngan NTT, Minh CV, et al. . Anti-inflammatory and PPAR transactivational properties of flavonoids from the roots of Sophora flavescens. Phytother Res 2013;27:1300–7. - PubMed

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