Tyrosinase Inhibitory Constituents from the Roots of Morus nigra: A Structure-Activity Relationship Study
Tyrosinase Inhibitory Constituents from the Roots of Morus nigra: A Structure-Activity Relationship Study
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DOI：
10.1021/jf1003607
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发表时间：
2010-05-12
影响因子：
6.1
通讯作者：
Wang, Mingfu
中科院分区：
文献类型：
--
作者：
Zheng, Zong-Ping;Cheng, Ka-Wing;Wang, Mingfu
采用高效液相色谱法对黑桑根和枝条的植物化学成分与已知含有氧化白藜芦醇和桑苷A的桑树老枝和幼枝的植物化学成分进行比较。发现M.黑根提取物含有一些未知的天然产物，具有潜在的酪氨酸酶抑制活性。采用95%乙醇提取法提取木霉根的乙醇提取物。在本研究中进一步研究了nigra。分离得到一个新化合物5 ′-香叶基1 - 5，7，2 ′，4 ′-四羟基黄酮和28个已知酚类化合物。通过质谱和核磁共振谱鉴定了它们的结构。9个化合物，5 '-香叶基-5，7，2'，4 '-四羟基黄酮，steppogenin-7-O-β-D-葡萄糖苷，2，4，2'，4 '-四羟基查耳酮，moracin N，kuwanon H，桑椹呋喃G，morachalcone A，氧化白藜芦醇-3'-O-β-D-葡萄糖苷和氧化白藜芦醇-2-O-β-D-葡萄糖苷表现出比曲酸更好的酪氨酸酶抑制活性。值得注意的是，2，4，2 '，4'-四羟基查耳酮和降查耳酮A的1050值分别是曲酸的757倍和328倍，表明它们具有开发为有效的天然酪氨酸酶抑制剂的巨大潜力。
The phytochemical profiles of Morus nigra roots and twigs were compared by HPLC with those of the old and young twigs of Morus alba which are known to contain oxyresveratrol and mulberroside A as major components. It was found that M. nigra root extract contains some unknown natural products with potential tyrosinase inhibitory activity. The extract (95% ethanol) of the roots of M. nigra was further investigated in this study. One new compound, 5'-gerany1-5,7,2',4'-tetrahydroxyflavone, and twenty-eight known phenolic compounds were isolated. Their structures were identified by mass spectrometry and NMR spectroscopy. Nine compounds, 5'-gerany1-5,7,2',4'-tetrahydroxyflavone, steppogenin-7-O-beta-D-glucoside, 2,4,2',4'-tetrahydroxychalcone, moracin N, kuwanon H, mulberrofuran G, morachalcone A, oxyresveratrol-3'-O-beta-D-glucopyranoside and oxyresveratrol-2-O-beta-D-glucopyranoside, showed better tyrosinase inhibitory activities than kojic acid. It was noteworthy that the 1050 values of 2,4,2',4'-tetrahydroxychalcone and rnorachalcone A were 757-fold and 328-fold lower than that of kojic acid, respectively, suggesting a great potential for their development as effective natural tyrosinase inhibitors.