title: Biotransformations of tocopherols by Streptomyces catenulae.
abstract: Streptomyces catenulae catalyzed the oxidation of alpha-tocopherol to alpha-tocopherolquinone. Nitrotocopherols isolated from S. catenulae grown in defined culture medium containing delta- and gamma-tocopherols are formed by a combination of enzymatic nitrate reduction to nitrite, and subsequent nonenzymatic acid-catalyzed nitration. The incorporation of 15N18O3-into nitrated tocopherols confirmed the origin of the nitrating species. Structures of chromatographically purified products obtained from S. catenulae transformations of tocopherols were deduced by spectral (mass spectrometry, 1H-, and 13C-nuclear magnetic resonance) analyses.
authors.affiliation: Division of Medicinal & Natural Products Chemistry, College of Pharmacy, University of Iowa, Iowa City 52242, USA.
authors.forename: B
authors.initials: B
authors.lastname: Rousseau
authors.forename: L
authors.initials: L
authors.lastname: Dostal
authors.forename: J P
authors.initials: JP
authors.lastname: Rosazza
mesh_terms: D001711:Biotransformation; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D015394:Molecular Structure; D009566:Nitrates / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D009574:Nitro Compounds / Q000378:metabolism; D013302:Streptomyces / Q000378:metabolism*; D014810:Vitamin E / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D009566:Nitrates; D009573:Nitrites; D009574:Nitro Compounds; D014810:Vitamin E