The microbial degradation pathways of bicyclic monoterpenes contain unknown enzymes for carbon-carbon cleavages. Such enzymes may also be present in the betaproteobacterium Castellaniella defragrans, a model organism to study the anaerobic monoterpene degradation. In this study, a deletion mutant strain missing the first enzyme of the monocyclic monoterpene pathway transformed cometabolically t...

A Baeyer-Villiger mono-oxygenase (BVMO), catalysing the NADPH- and oxygen-dependent oxidation of the monocyclic monoterpene ketones 1-hydroxy-2-oxolimonene, dihydrocarvone and menthone, was purified to homogeneity from Rhodococcus erythropolis DCL14. Monocyclic monoterpene ketone mono-oxygenase (MMKMO) is a monomeric enzyme of molecular mass 60 kDa. It contains 1 mol of FAD/monomer as the prost...

Orange peel oil is used extensively as an approved flavour enhancer in fruit drinks, carbonated beverages and as a scenting agent in soaps and cosmetics. Limonene, which is a monocyclic monoterpene is present in orange peel oil from 90 to 95% (w/w). Monoterpenes have been shown to be very effective chemopreventive agents against several rodent tumors and are currently in clinical trials. Howeve...

PURPOSE Carrying out the chemical composition and antiproliferative effects against cancer cells from different biological parts of Artemisia herba alba. METHODS Essential oils were studied by gas chromatography coupled to mass spectrometry (GC-MS) and their antitumoral activity was tested against P815 mastocytoma and BSR kidney carcinoma cell lines; also, in order to evaluate the effect on n...

The p-menthane monoterpenes of the Mentha species are biosynthesized from geranyl pyrophosphate via the monocyclic olefin 4S-limonene. A monoterpene cyclase was isolated from both Mentha x piperita (peppermint) and Mentha spicata (spearmint) that catalyzes the cyclization of geranyl pyrophosphate to 4S-limonene. This enzyme, 4S-limonene synthase, was purified to apparent homogeneity by dye liga...

As the basis and preliminary work of future experimental study on PAHs formation under high temperature, theoretical computations on the intramolecular rearrangement reactions of sylvestrene (1-methyl-3-vinylcyclohexene) and 1,4-dimethyl-4-vinylcyclohexene are conducted and reveal that they may be transformed to themselves. The conversion between Dipentene and 2,4-dimethyl-4-vinylcyclohexen...

Aromatic amines are an important group of industrial chemicals, which are widely used for manufacturing of dyes, pesticides, drugs, pigments, and other industrial products. These compounds have been considered highly toxic to human beings due to their carcinogenic nature. Three groups of aromatic amines have been recognized: monocyclic, polycyclic, and heterocyclic aromatic amines. Bacterial de...

New cis monocyclic beta-lactams were synthesized by [2+2] Staudinger cycloaddition reactions of the imine (3,4-dimethoxybenzylidene)-(4-methoxyphenyl)-amine and ketenes derived from different acyl chlorides and Et3N. These monocyclic beta-lactams were then cleaved by ceric ammonium nitrate (CAN) to give NH-monocyclic beta-lactams, which in turn were converted to N-sulfonyl monocyclic beta-lacta...