Aspergillus niger metabolism of citrus furanocoumarin inhibitors of human cytochrome P450 3A4

作者：Myung Kyung^*; Manthey John A; Narciso Jan A

来源：Applied Microbiology and Biotechnology, 2008, 78(2): 343-349.

DOI：10.1007/s00253-007-1314-0

• Aspergillus niger
• furanocoumarins
• 6', 7'-epoxybergamottin
• 6', 7'-dihydroxybergamottin
• bergamottin
• bergaptol
• xanthotoxol
• bergaptol-5-sulfate
• xanthotoxol-8-sulfate

Fungi metabolize polycyclic aromatic hydrocarbons by a number of detoxification processes, including the formation of sulfated and glycosidated conjugates. A class of aromatic compounds in grapefruit is the furanocoumarins (FCs), and their metabolism in humans is centrally involved in the "grapefruit/drug interactions." Thus far, the metabolism by fungi of the major FCs in grapefruit, including 6', 7'-epoxybergamottin (EB), 6', 7'-dihydroxybergamottin (DHB), and bergamottin (BM), has received little attention. In this study, Aspergillus niger was observed to convert EB into DHB and a novel water-soluble metabolite (WSM). Bergaptol (BT) and BM were also metabolized by A. niger to the WSM, which was identified as BT-5-sulfate using mass spectrometry, UV spectroscopy, chemical hydrolysis, and H-1 and C-13 nuclear magnetic resonance spectroscopy. Similarly, the fungus had a capability of metabolizing xanthotoxol (XT), a structural isomer of BT, to a sulfated analog of BT-5-sulfate, presumably XT-8-sulfate. A possible enzyme-catalyzed pathway for the grapefruit FC metabolism involving the cleavage of the geranyl group and the addition of a sulfate group is proposed.

• 出版日期2008-2