Vol. 43 No. 2 (219) (2009)

A brief review of in vitro and in vivo mutagenicity testing strategy and analysis of genotoxicity of new potential anticancer preparations (porphyrins derivatives) and anticancer preparation cisplatin with the comet assay, Comet-FISH and micronuclei test is presented. The directions presented are highly important for development of genetic toxicology in Armenia.

A maximum bubble pressure method has been used to study dynamic surface tension, $\gamma(t)$ of dibutylsulfoxide aqueous solutions at 0.0004-0.24 M concentration range. The $\gamma(t)$ decays were measured in the range of 30 ms to 60 s and analyzed in term of asymptotic solutions to the Ward and Tordai equation. The adsorption model provided by diffusion was applied to describe the surface mass transfer process and to predict the dynamic surface tension.

The influence of polyethylenglicole of various molecular mass on structural transformations of aqua soluble surface-active substance, sodium pentadecylsulfonate, has been investigated by methods of viscosimetry and light scattering in dependence of quantity of polymer in the system. It was established, that polyethylenglicole with molecular mass 2 000 and 40 000 has not influence on the structure of the system. Polyethylenglicole with molecular mass 4 000, 6 000 and 20 000 exhibits well-defined behavior of dependence of intrinsic viscosity on quantity of polymer. It was assumed, that changing the polyethylenglicole concentration in the system the compactization of micelle takes place due to changing the balance of hydrophobic-hydrophilic interactions. The change of appeared micelle mass and asymmetry coefficients which are established by the method of light scattering, has a simbate change with the dependence of intrinsic viscosity on the composition of mixture.

The level of the sorption of model mixture components composed of phenol, aniline, benzene, toluene and brombenzene by activated charcoal obtained from the Circassian walnut shell has been assessed by means of reversed-phase high performance liquid chromatography (RP-HPLC) method. The acetonitrile–water mixture (50:50 by volume) has been applied as mobile phase. The samples of activated charcoal have been prepared by means of dry distillation. Caustic soda, sodium carbonate, and orthophosphoric acid have been used as activators. The introduction of activators has been carried out by means of exposing the shell samples in the solutions of indicated reagents. The influence of the additional treatment of the obtained samples of activated charcoals by nitric acids on their sorption properties has been studied as well.

An interaction between biuret and formaldehyde has been developed, in consequence of which bis-methylol biuret has been obtained. On the base of that methylol derivative the unsaturated derivatives of biuret with carboxyl end-groups have been synthesised. The interaction of biuret with acetates of cadmium has been realized in the mass, in consequence of which cadmium’s complex compound of chelate type has been obtained. This compound has an ability to polymerize under the impact of enhanced temperatures and to generate the polymer of spatial structure. The obtained compounds have been studied by IR-spectroscopy and elemental analysis methods

Asymmetric addition of izopropylamine to C=C bond of Ni^II-complex Schiff`s base of dehydroalanine with modified chiral auxiliary (S)-N-(2-benzoilphenyl)-1-(2-chlorbenzyl)pyrrolidine-2-carboxamide was investigated and high selective method of asymmetric synthesis of non-protein amino acid (S)-β-N-izopropylaminoalanine (ee >97%) was developed.

An efficient method of asymmetric synthesis of (S)-N-(2-benzoylphenyl)-1-(2-chlorbenzyl)pyrrolidine-2-carboxamide via asymmetric C-alkylation of Ni(II)- complex of Schiff’s base with glycine and chiral auxiliary reagent (S)-N-(2-benzoylphenyl)-1-(2-chlorbenzyl)pyrrolidine-2-carboxamide by 3,4-dimethylbenzylchloride with following decomposition of the diastereomer complexes and isolation of the target optically active amino acid has been developed. The stereoselectivity of the C-alkylation reaction exceeds 91% and the optically purity of the isolated target α-amino acid – (S)-3,4-dimethylphenylalanine – 99%.

In the oxygen deficiency conditions we studied the influence of irritation of fornix stimulation on the impulse activity of the reticulary neurons and on the respiration. Phases of hypoxia were the model of experiment. At the initial stage of hypoxia (4000–5000 m higher) the frequency of reticulary neurons was growing. Against this background the facilitating influence of stimulation of fornix was less prominent, though it prevailed over its inhibiting action. At the maximal altitude (7500–8000 m higher) however, the frequency of stimuls was falling, and mainly the facilitating effect of stimulation of fornix was continuing. The rats after being brought back to the normal atmospheric pressure displayed gradual recovery of initial exponents with respect to both the ccof neurons and the reactions to stimulation. Those different reactions of irritation fornix have regulation sense on respiratory neurons

Dynamic changes of the anterior cortical activity under experimental modeling of conflict-inducing environment at teenagers with various level of an initial conflictness are investigated. Dependence of anterior cortical activity changes on gender and an initial level of the conflictness of examinees under the influence of conflict-inducing factor is found out. Obtained data have proved to be true also the revealed shifts in psychoemotional sphere.

A total of 111 strains of fluorescent pseudomonadеs were isolated from rice rhizosphere of different locals in the three provinces of North Iran and identified by standard methods. These isolates were tested for the production of indolylacetic acid (IAA). IAA production by studied strains in the presence of tryptophan (2 mg/mL) was recorded within the bounds of 17.69–95.89 mcg/mL. The level of IAA produced was estimated by a standard curve. Species with the largest quantities of IAA production (with rates more than average – 56.79 mcg/mL) were selected. Maximum rates of IAA production on average were 62.18 mcg/mL for Pseudomonas aeruginosa, 86.63 mcg/mL for P. putida and 68.42 mcg/mL for P. fluorescens.

The interaction of bichromate ions with tetramethylthionin by means of amperometric titration method has been studied. The titration may be carried in the following acidity range: 0.1–5.0 M by sulfuric acid and 0.1–1.0 M by hydrochloric acid. The molar ration between the acting components equals [Cr₂O₇ ^2-]:[TMT⁺ ]=1:2. The obeying to the main law of amperometry continued during the titration of 6.0⋅10^-5–1.3⋅10^-3 M (0.00624–0.14 mg/mL) bichromate solutions. The technique worked out has been tested analyzing chromium-containing ore with acceptable determination error values (2.44% rel.)