N-Acetylcysteine is an effective analog of glutathione in reactions with reactive oxygen species.

The kinetic characteristics of the interaction of N-acetylcysteine (ASH) with reactive oxygen species (ROS), peroxyl radicals and hydrogen peroxide were determined. It was found that in terms of activity ASH in these reactions is similar to glutathione GSH, the main endogenous bioantioxidant. The kinetics of heat release in the interaction of GSH and ASH with H2O2 was studied for the first time by isothermal calorimetry. It is shown that the kinetic curves of heat release and changes in specific heat release rates practically coincide for both thiols taken in the stoichiometric ratio in the known reaction 2 TSH + H2O2 → TSST + 2 H2O. This indicates the relative autonomy of the S-H and S-S bonds in thiols and disulfides, which are not affected by other groups in the molecule. At pH<7, ASH, like GSH, interacts with H2O2 to form thiyl radicals, which initiate thiol-ene reactions with unsaturated phenol resveratrol. Under the same conditions, ASH ensures nearly the same radical initiation rates as GSH, and thiyl radicals from ASH are close in activity to GS• in chain propagation reactions.

[The antiradical activity of plant extracts and healthful preventive combinations of these exrtacts with the phospholipid complex].

Using the chemiluminescence method, the effective concentration of antioxidants (AO) and its reactivity toward peroxyl radicals (ARA, the k7 constant) have been measured for 13 plant extracts. In fact all extracts demonstrated ARA higher than ionol. Larix dahurica, Hypericum perforatum, Potentilla fruticosa, Aronia melanocarpa and Rhaponticum carthamoides extracts showed the highest values of ARA. The combinations Aronia + Raponticum extracts; Larix + Hibiscus extracts; Schizandra +Aronia extracts were synergistic (the synergism effect beta of 38%, 33% and 22%). Apparently this phenomenon is the result of the synergistic interaction between compounds present in plant extracts. The Phospholipid complex--Lipoid S40, lacting any antioxidant effect alone, showed a potent synergistic effect with Aronia extract (beta3 = 60%), Silybum extract (beta3 = 41%). Clinical trials demonstrated, that combinations "Lipoid + Aronia extract", "Lipoid + Larix extract + Hibiscus extract", "Lipoid + Silybum extract", "Lipoid + Q10 + Rosa majalis extract" may be used as an additional component in the medicinal treatment, or as an individual prophylactic agent.

[Antioxidant activity of vegetable oils with various omega-6/omega-3 fatty acids ratio].

Antioxidant activity and the oxidative stability were investigated in flax, sesame, silybum oils and oils with different omega-6/omega-3 fatty acid ratio. The content of antioxidants (AO) in crude oils and their reactivity towards peroxyl radicals were studied using kinetic method for addition of oil in a model reaction of cumol oxidation. There were correlations between PUFA/omega-9 and thermal stability (50 degrees C); between gamma-tocopherol content and resistantance to oxidative changes after storage at (10 +/- 2) degrees C for 6 months.

[Antiradical activity and resistance of flaxseed oil enriched with the antioxidants to oxidative changes].

Using the chemiluminescence technique, the effective concentration of antioxidants (AO) and its reactivity towards peroxyl radicals (constant k7) have been measured for the oil "Ubicato-flax" (biological active supplement) and flaxseed oil, enriched with Aronia melanocarpa extract. Ubicato-flax exhibited the highest antiradical activity but it was less resistant to oxidative changes as compared with flaxseed oil + extract. Ubicato oil produced on basis of natural AO exhibited higher antiradical activity in comparison with Ubicato oil produced on basis of the chemical synthetic AO. Aronia extract added to flaxseed oil caused marked inhibition of the increase in the peroxide value. Ubicato-flax may serve as a source of AO for not more than 6 months.

[Pharmacological properties of phosphorylacetohydrazides in experimental myocardial ischemia].

It is shown that 2-chloroethoxy-para-N-dimethylphosphorylacetohydrazide and N-acethylhydrazide-para-dimethylaminophenyl-2-chloroethoxyphosphorylacetic acid reliably reduce ischemia-induced depression of inotropic functions of the left ventricle in cats with experimental myocardial infarction model. The effect of both compounds can be explained by the maintenance of viability of the injured myocardium via a delay of the development of acidosis and the support of oxygen recycling in the ischemized zone. Both compounds show pronounced antiradical properties with a non-standard mechanism of action.

[Antioxidant properties of a leaf extract from Aronia (Aronia melanocarba) containing proanthocyanidins]. / Antioksidantnye svoistva ékstrakta list'ev aronii (Aronia melanocarpa), soderzhashchego proantotsianidininy.

Antioxidant capacity of a procyanidin-containing extract from Aronia melanocarpa leaves has been studied in vitro and in vivo. Using the chemiluminescence technique, the effective content of antioxidants and its reactivity towards peroxyl radicals have been measured in a model reaction of initiated oxidation of hydrocarbon for the whole extract and two of its chromatographic fractions separated by HPLC. The results indicate that the extract contains a combination of antioxidants with different radical scavenging activities. The value of the rate constant of the reaction with peroxyl radicals (constant k7) for the extract strong inhibitors is of the same order of that for alpha-tocopherol and its synthetic analog chroman C. A decrease in antiradical activity directly related to the high concentrations of this extract in reactive mixture has been observed. This extract significantly reduced in dose-dependent fashion the CCl4-induced hepatic lipid peroxidation. The extract also inhibited flaxseed oil peroxidation. The present study indicates significant antioxidant capacity of the extract from Aronia melanocarpa leaves.

[Antioxidant activity of flaxseed oil]. / Antioksidantnaia aktivnost' l'nianogo masla.

Effective concentration of antioxidants and its reactivity toward peroxil radicals (constant k7) have been measured by the chemiluminescence technique for flaxseed oil. Effective concentration of antioxidants is shown to depend on the technology of producing flaxseed oil; period of seed storage before use; and storing duration of flaxseed oil also. Minor component content of flaxseed oil, which may be the members of antioxidant pool, has been quantitatively estimated.