Vol. 44 No. 1 (221) (2010)

The complex formation between Vitamin D₂ and dimetylsulfoxide (DMSO) and diethylsulfoxide (DESO) in tetrachloromethane has been studied on the basis of FT IR spectroscopic measurements. The results obtained show that complex formation between Vitamin D₂ and sulfoxide occurs through hydrogen bond of the type O–H...O=S. The equilibrium constants of Vitamin D₂–DMSO and Vitamin D₂–DESO complexes were determined at 23 ^oC.

The effect of dialkylsulfoxides (DASO) on the thermal denaturation of DNA was studied by fluoresence spectroscopy. As a fluorescence probe the ethidium bromide was used. It is revealed, that DASO shows expressed denaturing ability. In series of DMSO–DESO–DPSO with increasing of hydrocarbonic chain length of sulfoxides their denaturing ability increases, which is caused by the increase of direct hydrophobic interactions between DNA–DASO.

Using gasometric method at 303 K the action of 2-cyano-3,4,4-trimethyl-2-butene-4-olid unsaturated lacton on the Η₂Ο₂ + ΗΟΟ^- reaction rate has been studied . Taking into consideration the fact that the mentioned lacton is oilsoluble its water-ethanol solutions, as well micellar systems obtained making use two kinds of surfactants: C₁₂H₂₅SO⁻₄Na⁺ and C₁₂H₂₅ N⁺(CH)₃Cl⁻. It has been established that in lacton absence: 

− EtOH decreases the reaction rate (R), but in presence of lacton there is some increase in R value. This phenomenon is discussed in detail.

− In micellar systems the lacton action is similar. There is one difference. After some increase in micelles concentration the reaction rate in lacton presence becomes lower than the R value, determined in lacton absence. This regularity is also discussed in detail, as well as the RNO^• action.

The interaction of chrome(III) with tartaric acid is studied by the methods of ion exchange and spectral photometry. It is determined that the complex formation takes place in discrete steps to  Cr$^{3+}$ : HC₄H₄O$^−_6$ equal to 1:1, 1:2 and 1:3 at temperature 20 ± 2 ^oC. Stepwise and general stability constants for the complexes are defined.

Interaction of phenylthiourea (PTU) with manganese (VII) and chromium (VI) has been studied by means of the potentiometry, spectrophotometry and amperometry methods. It has been established that the molar ration of the reacting components is Mn(VII) : PTU = 3 : 2 and Cr(VI) : PTU = 2 : 1 correspondingly. The conformity to the amperometry main law is observed within 5.0·10^-6 (0.00275 mg/mL)–1.0·10^-2 М (0.55 mg/mL) and 1.0·10^-5 M (0.00112 mg/mL)–7.71·10^-4 M (0.086 mg/mL) concentration ranges for Mn (VII) and Cr (VI) correspondingly. The method of potentiometric titration of chromium by PTU has been applied for its determination in the chromium-containing ore with 0.87% relative error.

New fluorine-containing chiral auxiliary (S)-N-(2-benzoyl-phenyl)-1-(2- fluorobenzyl)pyrolidyne-2-carboxamide ((S)-2-FBPB) and its plane-square Ni(II) complex of Shiff base with serine is synthesized. The synthesis of chiral auxiliary has been carried out in the presence of CH₂Cl₂ at 0 ^oC via condensation of 2-aminobenzophenone with 2-fluorobenzylproline, through intermediate formation of chloranhydride in the presence of PCl₅. The synthesis was carried out in CH₃OH in the presense of strong base (KOH). As expected during the synthesis of the serine complex with new fluorine-containing chiral auxiliary (S)-2-FBPB of diastereoizomeric complexes (S,R)/(S,S) in a ratio 99/1 has been derived.

In this work the mathematical model of kinetics of ligands adsorption on duplexes of DNA with the account of diffusion as well as kinetic stages is constructed. The case when the volume solution directly adjoins to immobilized molecules of DNA is considered. The numerical analysis of nonlinear equations system describing the process of adsorption shows that various variants of adsorption can be realized in a solution depending on a parity between constants of ligands adsorption and desorption rates on DNA, as well as ligands rate diffusion.

In this article is reported about fungal species contaminating spices: red pepper, black pepper, suneli, carry. Data about 29 species of fungi contaminating spices are given. Isolated species belong to Zygomycetes and Deuteromycetes classes. 21 species belong to Moniliaceae family.

With the help of light and scanning electron microscopes the palynomorphological investigation of 39 species of the genus Cuscuta L. has been carried out. The data obtained specify the considerable affinity of the subgenera Grammica and Cuscuta on the morphological type of pollen. At the same time, according to the palynomorphological data, the species of subgenus Monogyna occupy some isolated position in the genus Cuscuta.

At the Institute of Biotechnology RA on the basis of industrial strain Bacillus thuringiensis, which is used in the production of bacterial insecticides, mutant strain was obtained – the producer of water-soluble melanin. The stimulating influence of bacterial melanin preparation was revealed on the growth and development of cucumber both in vitro and in vivo conditions.

The interaction of analginum anion with dye of triphenilmethane brilliant green has been studied. Formed ionic associate could be removed once shot extraction (R=0.96) by dichlorethane–amylacetate (1:2) binary mixture in pH 1 (H₂SO₄) solutions. The extracts of ionic associate are submited with the main law of spectrophotometer in the 0.9–20 mcg/mL range of analginum contents ( ε =2.3 ⋅10⁴ L⋅mol⋅cm). The elaborated method has been applied for determination of analginum in baralgetase, spasmalgonum and benalginum. In the case of tempalgin low results have been received.

Interaction of rodanid anion complex of palladium (II) with triphenyl raw organic basic dye methyl green in sulfuric acid environment has been studied. The optimal conditions for the formation of ionic associate (IA) and its extraction in organic phase, also concentration of dye, the range of palladium (II) content selectivity of extraction are determined. The content of IA is determined.

The inactivation of the rat liver arginase in condition of pH 3.6 during different time periods and different ionic powers of gly–HCl buffer (0.05; 0.1 and 0.2 M) was examined. In fact, the increase of buffer molarity observes the certain increase of enzyme inactivation percent. Inactivation also depends on ionic power of tris–HCl (pH 7.4) buffer. Maximum percent of reactivation was discovered in 0.01 M of buffer tris–HCl (pH 7.4) with Mn²⁺ ions during 12 hours’ incubation.