BIOTRANSFORMATIONS OF TOCOPHEROLS BY STREPTOMYCES-CATENULAE

Streptomyces catenulae catalyzed the oxidation of alpha-tocopherol to alpha-tocopherolquinone. Nitrotocopherols isolated from S. catenulae g rown 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 incorporat ion of (NO3-)-N-15-O-18 into nitrated tocopherols confirmed the origin of the nitrating species. Structures of chromatographically purified products obtained from S. catenulae transformations of tocopherols wer e deduced by spectral (mass spectrometry, H-1-, and C-13-nuclear magne tic resonance) analyses.