Production of Two Novel Methoxy-Isoflavones from Biotransformation of 8-Hydroxydaidzein by Recombinant Escherichia coli Expressing O-Methyltransferase SpOMT2884 from Streptomyces peucetius

International Journal of Molecular Sciences

Chien-Min Chiang³  Hsiou-Yu Ding¹  Ya-Ting Tsai²  Te-Sheng Chang² 

[1] Department of Cosmetics Science, Chia Nan University of Pharmacy & Science, No. 60, Sec. 1, Erh-Jen Rd., Jen-Te District, Tainan 71710, Taiwan;Department of Biological Sciences and Technology, National University of Tainan, No. 33, Sec. 2, Shu-Lin St., Tainan 70005, Taiwan;Department of Biotechnology, Chia Nan University of Pharmacy & Science, No. 60, Sec. 1, Erh-Jen Rd., Jen-Te District, Tainan 71710, Taiwan;

关键词: 7;    4′-dihydroxy-8-methoxy-isoflavone;    8;    4′-dihydroxy-7-methoxy-isoflavone;    8-hydroxydaidzein;    melanogenesis;    inhibition;    O-methyltransferase;    SpOMT2884;   

DOI  :  10.3390/ijms161126070

来源: mdpi

【 摘 要 】

Biotransformation of 8-hydroxydaidzein by recombinant Escherichia coli expressing O-methyltransferase (OMT) SpOMT2884 from Streptomyces peucetius was investigated. Two metabolites were isolated and identified as 7,4′-dihydroxy-8-methoxy-isoflavone (1) and 8,4′-dihydroxy-7-methoxy-isoflavone (2), based on mass, 1H-nuclear magnetic resonance (NMR) and 13C-NMR spectrophotometric analysis. The maximum production yields of compound (1) and (2) in a 5-L fermenter were 9.3 mg/L and 6.0 mg/L, respectively. The two methoxy-isoflavones showed dose-dependent inhibitory effects on melanogenesis in cultured B16 melanoma cells under non-toxic conditions. Among the effects, compound (1) decreased melanogenesis to 63.5% of the control at 25 μM. This is the first report on the 8-O-methylation activity of OMT toward isoflavones. In addition, the present study also first identified compound (1) with potent melanogenesis inhibitory activity.

【 授权许可】

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