Model Reaction Of Cumene Oxidation Research Articles

ANTIOXIDANT ACTIVITY OF THE ETHYL ACETATE EXTRACT OF DIFFERENT TYPES OF THE THOUSAND (ACHILLEA L.)

For the treatment of various diseases in the traditional medicine for a long time different types of yarrow are used. Medicines from yarrow have medicinal properties and render styptic, spazmolitic, wound healing, bile-expelling action. They also show antioxidant, antibacterial and antifungal activity. Medicinal properties of these medicines are caused by existence in them of phenolic compounds (flavonoids, tannins, vitamin C). The purpose of this work is a research of antioxidant properties of ethylacetate extracts preparing from different types of yarrows growing in a South-East part of the Republic of Armenia. Experimental data of antioxidant activities (AOA) and effective content of antioxidants (AO) in the ethylacetate extracts of three tipes of yarrows are given in this study on the example of model reaction of cumene oxidation. It is shown that the studied yarrows are distributed in a row by the effective content of antioxidants: Achilleaaurea>Achillea nobilis>Achillea millefolium, and by the antioxidant activitiy: Achillea millefolium>Achillea nobilis>Achillea aurea.On the examples of extracts mixtures from the leaves and flowers of Achillea millefolium and also from the leaves and flowers of Achillea nobilis the synergism effect of cumene’s oxidation inhibition is found, respectively, 30 and 21%.

Antioxidant activity of vegetable oils with different omega-6/omega-3 fatty acids ratio

The antioxidant activity and the oxidative stability of flax, sesame, silybum oils and seed blend oils with different ω-6/ω-3 fatty acid ratios have been investigated. The antioxidant content (AO) in crude oils and their reactivity towards peroxyl radicals were studied using the kinetic method based on oil addition to the model reaction of cumene oxidation. There were correlations between the ratio polyunsaturated fatty acids (PUFA)/ω-9 and thermal stability (50°C); between the effect of γ-tocopherol content and oil resistance to oxidative changes during long-term storage at (10 ± 2)°C.

Tribochemical Component of Oxidizing Stress Development at Joint Replacement. Part I. Determination of Radical-Forming Ability of Wear Particles from Various Orthopaedic Materials

Using the model reaction of cumene oxidation the radical-forming ability of wear particles of some orthopaedic alloys and corundum ceramics were studied. It was revealed that wear particles from different alloys catalyzed cumene oxidation whereas particles of corundum ceramics were inert. Cobalt alloy wear particles were much more active as compared with the titanium alloy and stainless steel particles. Production of cobalt alloy by laser sintering reduced the radical-forming ability of its wear particles. Activity of cobalt wear particles was preserved for a long time after their formation and could considerably strengthen the development of oxidizing stress at joint arthroplasty. Detection of catalytic activity of orthopaedic alloys' wear particles requires studying of the influence of free radicals generated by tribochemical reaction upon implant components and biological tissues.

Antioxidant properties of sulfides derived from 2-propylphenol and of their aminomethyl derivatives

Antioxidant properties of sulfides derived from 2-propylphenol and of their aminomethyl derivatives were studied in a model reaction of cumene oxidation. The kinetic parameters of the reactions of these compounds with cumylperoxy radicals and cumyl hydroperoxide were determined.