European Journal of Molecular Biotechnology

69-75

Authors: Abdelilah Benallou

The optimum geometries and quadratic force constants of HCN, HNC, intermediates (INT1 and INT2) and the transition state connecting them (CHN) have been determined at the DFT (density functional theory) level of theory. Energy differences were evaluated using the DFT method in conjunction with 6-311++g(d,p) basis set. The most reliable structure obtained for the transition state has bond distances of 1.184, 1.193 and 1.391Å for rCN, rCH and rNH, respectively. Including a correction for zero-point vibrational energies, the transition state activation energy is predicted to be 44.6kcal/mol. So the transition state of isomerization pathway is highly energetic and subsequently cannot occur efficiently in the gas phase.

83-95

Authors: H.A. Shindy, M.A. El-Maghraby, M.M. Goma a, N.A. Harb

New polyheterocyclic starting material compound namely 3, 5-dimethyl-7-phenyl-furo [(3,2-d) pyrazole;(3',2'-d) oxazole] was prepared and oriented for the synthesis of novel monomethine cyanine dyes (simple cyanine dyes), bis monomethine cyanine dyes (bis simple cyanine dyes), trimethine cyanine dyes (carbocyanine dyes) and bis trimethine cyanine dyes (bis carbocyanine dyes). The electronic transitions of all the synthesized cyanine dyes were evaluated and determined through investigating their visible absorption spectra in 95 % ethanol solution. The dyes were thought to be better electronic transitions when they absorb light at higher wavelength bands (bathochromic shifted and/or red shifted dyes). Consequently, the electronic transitions of the dyes decreases when they absorb light at lower wavelength bands (hypsochromic shifted and/or blue shifted dyes). The antimicrobial activity evaluation for a number of 10 (ten) selected compounds was tested against 4 (four) various bacterial strains (Bacillus subtilis, Escherichia coli, Pseudomona aeruginosa and Staphylococcus aureus). The antimicrobial activity evaluation can be made through measuring the inhibition zone diameter of the tested compounds against a number of bacterial and/or fungi strains. The compounds were thought to be better antimicrobial active when they give higher inhibition zone diameter against the tested bacterial and/or the fungi strains. Consequently, the antimicrobial activity of the compounds decrease when they give lower inhibition zone diameter against the tested bacterial and/or the fungi strains. Structural characterization and determination was carried out via elemental analysis, visible, mass, IR and 1HNMR spectroscopic data.

3-15

Authors: Abdelilah Benallou, Habib El Alaoui El Abdallaoui, Hocine Garmes

A detailed mechanistic study by molecular electron density of the Hetero-Diels-Alder (HDA) reaction of isoselenazole with unsymmetrical acetylenic dienophile is carried out. The high activation energy involved in the transition state of both Ortho and Meta cycloadduct implies that this reaction may not possible, even in the presence of solvent toluene. Besides, ELF shows that the not formation of the basin at the N2 nitrogen atom of isoselenazole moiety. Therefore, the negligible charge transfer between reagents and the large electron density attracted by the lone pair at the N2 atom, in addition to the C1SeN2 fragment distortion energy cost, they are not allowing the formation of the radicals (basins) necessary at the most significant atoms, these factors are probably responsible for the highest barrier activation.

25-40

Authors: Ignat Ignatov, Yuliana Pesheva

This review article views predominately the structure and function of animal and bacterial photoreceptor pigments (rhodopsin, iodopsin, bacteriorhodopsin) and their aspects of nano- and biotechnological usage. On an example of bacteriorhodopsin is described the method of its isolation from purple membranes of photo-organotrophic halobacterium Halobacterium halobium by cellular autolysis by distilled water, processing of bacterial biomass by ultrasound at 22 KHz, alcohol extraction of low and high-weight molecular impurities, cellular RNA, carotenoids and lipids, the solubilization with 0,5 % (w/v) SDS-Na and subsequent fractionation by methanol and gel filtration chromatography on Sephadex G-200 Column balanced with 0.09 M Tris-borate buffer (pH = 8,35) with 0,1 % (w/v) SDS-Na and 2,5 mM EDTA. Within the framework of the research the mechanism of color perception by the visual analyzer having the ability to analyze certain ranges of the optical spectrum, as colors was studied along with an analysis of the additive mixing of two colors. It was shown that at the mixing of electromagnetic waves with different wavelengths, the visual analyzer perceive them as separate or average wave length corresponding to mix colors (Marinov, Ignatov, 2008).

53-60

Authors: Elena A. Ivantsova, Nikolay V. Onistratenko, Nadezhda V. German, Pavel A. Krylov, Anna A. Tikhonova, Valery V. Novochadov

The article presents the results of the study to analyze the plant and microbial soil associations in the composition of agrocenoses, natural steppe biocenoses and territorially integral areas of grasses on the border or within agrocenoses, mainly anthropogenic origin, named in the article as ‘intrusions’. We show the key relationships between the main participants (47 plant species and 24 species of soil microorganisms, ranked by number in the association) in concurrence for the assimilation of soil trace elements. On the basis of data on the number, main phenological characteristics of plants and microorganisms, as well as the content of manganese, nickel, copper and zinc in the soil, the main consort bonds in this biosystem were identified. The analysis of the general influence of concrete intrusions on the adjacent agrocenosis made it possible to identify trace elements and types of soil microorganisms, which increase helped to limit the negative impact of intrusions. The obtained data can be used to form biotechnologies for optimization of agrocenoses in the conditions of the arid zone.