In previous publications from this laboratory we have described a soluble, partially purified cytochrome P-450-dependent monooxygenase complex that, in the presence of NADPH and O2, catalyzes the monohydroxylation of long chain fatty acids, alcohols, and amides at the omega -1, omega -2, and omega -3 positions. We have now found that this preparation catalyzes the epoxidation as well as the hyd...

Calixarene-Ti complexes were grafted onto SiO2 (0.18-0.24 Ti nm-2) to form isolated and accessible Ti centers persistently coordinated to multidentate calixarene ligands. Grafted Ti-tert-butylcalix[4]arenes gave Ti K-edge absorption spectra with pre-edge features at 4968.6-4968.9 eV, independently of Ti surface density and of their use in epoxidation catalysis. The structure and reactivity of g...

The metabolism of the carcinogenic mycotoxin aflatoxin B1 (AFB1) was examined in microsomes derived from human lymphoblastoid cell lines expressing transfected CYP1A2 or CYP3A4 complementary DNAs and in microsomes prepared from human liver donors (n = 4). Lymphoblast microsomes expressing only CYP1A2 activated AFB1 to AFB1-8,9-epoxide (AFB1-8,9-epoxide trapped as the glutathione, conjugate) at ...

Linseed oil is characterized by an elevated concentration of highly unsaturated fatty acids such as linolenic and linoleic acids. This work has the objective to evaluate effect high unsaturation linseed on reactivity selectivity epoxidation reaction. For this purpose, different kinetic experiments with performic acid, produced in situ, phosphoric acid catalyst, have been performed interpreted a...

Fluorinated Fe-porphyrins, especially [tetrakis(pentafluorophenyl)porphyrinato]iron(III) chloride (tetrakis(pentafluorophenyl)porphyrinato = TPFPP) (TPFPP)FeCl (Fepor-2a), were found to be highly efficient for catalyzing the double epoxidation of divinylbenzene (DVB) to divinylbenzene dioxide (DVBDO), a novel component of epoxy resin formulation. The electronic properties of the catalysts are h...

Herein we describe the development of a reactor for continuous flow generation and use dimethyldioxirane (DMDO) its application to low-level epoxidation unsaturated polymers.

Hematin catalyzes the epoxidation of 7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (BP-7,8-diol) by 13-hydroperoxy-9-cis,11-trans-octadecadienoic acid and other fatty acid hydroperoxides in the presence of detergent. The major oxidation product is the anti-dihydrodiolepoxide and the minor product is the syn-dihydrodiolepoxide. (+)-BP-7,8-diol is oxidized to (-)-anti-diolepoxide and (+)-syn-diolepoxid...

Two xanthophyll cycles have been described in higher plants: the violaxanthin xanthophyll (V or VAZ) cycle, which is present in all species, and the taxonomically restricted lutein epoxide xanthophyll (Lx) cycle, which involves the light-induced de-epoxidation of Lx to lutein (L) and its epoxidation back to Lx in low light. Laboratory experiments indicate that the first reaction occurs quickly,...

The light irradiation parameters, including the wavelength spectrum and intensity of light source, can significantly influence a photocatalytic reaction. This study examines the propylene photo-epoxidation over V-Ti/MCM-41 photocatalyst by using artificial sunlight (Xe lamp with/without an Air Mass 1.5 Global Filter at 1.6/18.5 mW·cm(-2)) and ultraviolet light (Mercury Arc lamp with different f...

Detergent-solubilized and partially purified soybean peroxygenase was shown to actively catalyze, in the presence of alkylhydroperoxides as co-substrates, the epoxidation of mono- and polyunsaturated fatty acids such as oleic and linoleic acids. Octadecenoic acids were found to be better substrates than shorter mono-unsaturated fatty acids (C16:1 or C14:1), but the position of their double bond...