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It was found that ants significantly affect the physiological activity and functional diversity of soil microbial communities, and redistribution of biophilic elements (C and N) down through the profile occurs in anthills compared to the control soil, as well as their accumulation in the underground part of the ant nests. A high urease activity was revealed in ant nests and ants. Functional dissimilarities of bacterial communities in all studied objects were determined by the miultisubstrate test.

We present results of the analysis of long-term chlorophyll a dynamics in the Naroch lakes. It has been shown that an increase in nutrient load in the 1970s resulted in progressive eutrophication of Naroch lakes. Then, starting in the mid-1980s, the increase in water transparency and decreases in concentrations of phosphorus and nitrogen have been occurring due to the environmental improvement program. In the 1980s, the Naroch lakes experienced a strong factor as an invasion by zebra mussel (Dreissena polymorpha Pallas). Our analysis shows that responses of all three lakes to the intensive nutrient load and further decrease in the nutrient concentration as a result of the environmental protection measures have been correlated. At the same time, different degrees of the influence of the zebra mussel invasion on the lakes are shown to lead to divergence in chlorophyll dynamics. This divergence was observed as a drastic decline in correlations between variations in chlorophyll concentrations in every Naroch lakes.

The effect of southern (Microtus rossiaemeridionalis) and bank (Clethrionomys glareolus) voles on the biological activity of soddy-podzolic soil and culturozem has been studied. To estimate this effect, the activity of nitrogen and carbon transformation in the soil taken from the paths and different chambers of the holes of these rodents, as well as from the control plots where there were no voles, has been determined. The contents of organic carbon and nitrogen in the soil have been found. The parameters of functional diversity of the microbial community of soil have been studied. It has been noted that the effect of voles on the biological activity of the above soils manifested itself in increased intensity of aerobic and anaerobic destruction of organic matter and changes in the parameters of functional diversity of the microbial community of soils.

It was shown that the association of probiotic bacteria of the genuses Bacillus and Cellulomonas form biolayers on the surface of beet marc particles. The positive effect of a fodder additive that contained the biolayer on the basis of a phytomatrix on the growth and development of young rabbits was shown. Feeding of animals with a mixed fodder that contained 0.1% preparation resulted in stimulation of digestion of all components of the food. Among other components of the mixed fodder, cellulose was digested most effectively. An increase in the biomass of symbiotic bacteria and enzymatic activity in the blindgut chymus was also observed. The positive nitrogen balance demonstrated an increase in the nitrogen content in animals and a decrease of its losses with excretion. The mechanism of response of the rabbit's organism to introduction of the complex probiotic preparation into the digestive tract is discussed.

Hydrological and hydrochemical features of the sources of radon- and nitrogen-containing thermal waters of the Altai region are considered. Data on the chemical composition of mineral waters from different sources are presented. Methods for the use of radon- and nitrogen-containing thermal waters from their natural sources of the Altai region for the purpose of sanatorium and spa treatment are described.

The nitrogen-fixing activity, nitrogen (N) and carbon (C) contents, and the number of microorganisms in the forestomach, cecum, and segmented intestine were detected in two gerbil species, granivorous Meriones meridianus and M. tamariscinus, which consume a large amount of green parts of the plants. M. meridianus had higher levels of nitrogen-fixation activity in all investigated parts of the gastro-intestinal tract compared with M. tamariscinus. The highest levels were detected in the colon of M. meridianus. The C/N ratios in the forestomach of M. tamariscinus were higher than in M. meridianus, which is consistent with the greater role of the green parts of plants in its diet. A gradual increase in the nitrogen content from the forestomach to the colon of M. tamariscinus was noted. The amount of microorganisms in the forestomach and intestine of the studied gerbil species was similar.

Nitrogenase activity, the abundance of diazotrophic bacteria, the structure and functional characteristics of the complex of microorganisms, and the content of nitrogen and carbon were determined in the contents of the gastrointestinal tract of the European beaver. A high nitrogen-fixing activity in the large intestine correlated with an increase in nitrogen content in the chyme upon its transfer over the gastrointestinal tract. It is assumed that microbial nitrogen fixation plays a major role in nitrogen nutrition of the European beaver.

The influence of tamarisk (Meriones tamariscinus) and midday (M. meridianus) gerbils on soil biological activity in the Chernye Zemli, Kalmykia, was studied. Nitrogen fixation, denitrification, and CO2 emission were measured in soil samples from different parts of gerbil burrows. Functional biodiversity of the microbial community was evaluated using multisubstrate testing and comparison of bacterial group composition in samples from gerbil burrows. The impact of gerbils on soil biological activity was mediated by the changes in the group composition of microorganisms.

The influence of high concentrations of mineral nitrogen, phosphorus and their mixtures on species structure of microbenthos of a sand intertidal zone of the White Sea was studies in field experiment. The increase in concentration of nutrients (in comparison with natural) reduces the species diversity and organism abundance in grazing chains, but stimulates the development of organisms of detrital food chain. At abnormally high concentration of nutrients the response of community does not strictly depend on chemical composition of fertilizers and N:P atomic ratio. The high concentration of nutrients act as distructive agent on the complex organized system and simultaneously as a specific trigger of self organization processes, which re resulted in formation of highly coherent commynity of r-strategists (bacteria and protists). After termination of the experiment and resetting of environment to the previous state, the new community for a long time (measured by dozens of generations of unicellular organisms) retains its structure.

Quantitative data on the nutritional requirements of microorganisms are necessary to predict the behavior of bacterial populations and to control their cultivation. The requirements of the R, S, and M dissociants of Pseudomonas aeruginosa for carbon, nitrogen, and phosphorus were derived from the results of 88 cultivation experiments. For each of the dissociants, we derived a coefficient that relates the optical density and the number of cells in the dissociant culture, determined the time when the cultures entered the stationary growth phase, studied cultural changes induced by transfer to the stationary phase, and determined what nutrients limit the growth of particular dissociants. The nutritional requirements of the dissociants are discussed in relation to our earlier data.

Using Hayman's model of genetic analysis of the F1 hybrids from crosses between early- and late-ripening forms of cotton Gossypium hirsutum L., we examined inheritance of the duration of vegetative period at various contents of nitrogen in soil. Two variants of hybrid plants were studied. With the natural content of soil nitrogen, incomplete directionally dominance of earliness over late ripening with prevalence of additive gene effect of nonallelic interactions was observed. The genetic formulas of this trait proved to change with varying nitrogen nutrition.

The influence of refrigerator storage on the quality of high-protein raw sea material and its products was studied by using squids as an example. The size of microorganisms in 1 g, the content of nitrogen of volatile bases, that of non-protein nitrogen, and the amount of free amino acids were estimated after cooling and freezing and during storage of frozen squids. In parallel, the relative food value of the cooled and frozen squids and their products were determined by biotesting by means of Tetrachymena pyriformis. Refrigerator storage of squids leads to its muscular tissue degradation whose depth determines the loss of their food value. The results of biotesting of squid meat with the infusoria Tetrachymena pyriformis completely correlate with the data of chemical analysis while assessing the quality.

The analysis of the absorption spectra of the low-molecular-weight nitrogen-containing secondary metabolites--alkaloids--of 4 Penicillium chrysogenum strains and 6 Penicillium expansum strains isolated on board the Mir space station showed that all these strains synthesize metabolites of alkaloid origin (roquefortine, 3,12-dihydroroquefortine, meleagrin, viridicatin, viridicatol, isorugulosuvin, rugulosuvin B, N-acetyl-tryptamine, and a "yellow metabolite" containing the benzoquinone chromophore).

The biochemical method for determination of cetyltrimethyl ammonium or cetylpyridinium, both being nitrogenated cationic surfactants, has been devised by using horse blood serum butyrylcholinesterase as analytical reagent. The method streams from the fact that surfactants tested are inhibitors of butyrylcholinesterase hydrolysis of butyrylcholin, a cationic substrate, but in this case they activate enzymatic hydrolysis of 1-naphthylacetate, a neutral substrate. Presence two opposite effects enlarges reliability to identifications. Use the sensitive fluorimetric method to registrations of activation of hydrolysis a substrate 1-naphtylacetate vastly to reduce the threshold of determination of surfactants above.

In case of acute hypoxic hypoxia argon in the gas environment is favorable to survivability of laboratory animals (rats). Our purpose was to evaluate effects of an argon-containing hypoxic gas environment on embryogenesis of the Japanese quail (Cortunix cortunix japonica). Eggs of the Japanese quail were incubated in a pressurized chamber with a hypoxic gas environment differing in concentration of nitrogen and argon. In hypoxic (10% O2) oxygen-nitrogen and oxygen-nitrogen-argon atmospheres total mortality of embryos was observed no later than on day 7 of development. These gas mixtures also had a teratogenic effect. However, about 55% of argon in atmosphere prevented completely microcephalia and reduced in half incidence of other pathologies.

The procedures of definition amino nitrogen (sum amino acids) and imidazole compounds in human oral fluid are described. Amino nitrogen were determined by the ninhydrin method modified by the authors, imidazole compounds by the Pauli test. A total of over 20 patients with the relatively good dental status were surveyed. The level of amino nitrogen showed noticeable fluctuations (2.01 +/- 1.24 mmol per ml of oral fluid), whereas the content of imidazole derivatives was more stable (0.71 +/- 0.19 mmol/ml). Oral fluid samples displayed an in vitro high proteolytic activity, which explains contradictory results in the determination of the levels of amino nitrogen.

The influence of common vole Microtus arvalis on processes of nitrogen fixation and denitrification in the soddy-podsolic soil was studied. In the common vole colonies, the level of nitrogen fixation was reliably lower and that of denitrification higher, than in the control soil outside these colonies. Nitrogen-containing excretory products of voles accumulating in the soil are among the main factors that determine the activity of these processes.

Qualitative and quantitative composition and time course of formation of toxic substances during burning of polymers have been studied for two polymers, P-53-P and STBO. The most toxic gaseous products of nitrogen combustion are listed: hydrogen cyanide, nitrites, acid nitriles, aldehydes, aromatic carbohydrates, alkanes, and carbon oxide. Two expert conclusions are presented, including analysis of blood and viscera from subjects who died during fire. The following toxic substances were detected: carbon oxide, hydrogen cyanide, nitrites, acrylonitrile, acetonitrile, benzene, and methane in one case and the same products except carbon oxide in the other. The author considers that the list of tested toxic substances should be extended, particularly in cases with negative results of blood testing for carbon oxide and carboxyhemoglobin.

The effect of the ammonium nitrate (concentrations 2000, 4000, 6000 mg/l) on the content of urea, urea nitrogen and residual nitrogen in the haemolymph of normal Planorbarius purpura and in trematode-infected individuals. It is shown, that stimulation of metabolic processes is more expressed in uninfected specimens, while the trematode-infected ones, the protective process is strained. When the toxin concentration reaches 6000 mg/l, the trematode infected specimens enter the phase of depression with 3.73% hyponitrogen level.

Metabolism of sLt during Russian-US experiment GREENHOUSE-2 (July 9, 1996-January 17, 1997) within the MIR/NASA space research program and in laboratory Svet experiments in 1995-1996 was studied. Chemical, biochemical and pigment analyses of the flight and laboratory plants were made after the first (dry biomass) and second vegetation (photosynthetically active 41-d old plants). Data on the composition of leaves and stems of ground and flight wheat do not attest any biologically significant shifts in plant metabolism. There were slight changes in accumulation and migration of several macro- and microelements, protein nitrogen and phosphororganic compounds in microgravity. Lowered content of lignin, a critical supportive element for cellular walls was observed only during early stages of vegetation. In the Mir experiment, concentrations of photosynthetically active pigments also decreased a little but the chlorophyills-carotenoids balance was not upset.

The review summarizes the literature data on distribution of nitrogen-containing mycotoxins (alkaloids) among Penicillium and Aspergillus fungi infesting grain and products of grain processing. Particular attention in given to clavins (ergotalkaloids) and tremorgens (roquefortine, verruculogen, penitrems).

The influence of various nitrogen functional groups used for extraction cleanup and determination of N-containing mycotoxins (NM) in feeds and foodstuffs have been considered. TLC and LC are the most common techniques for detection and determination of nitrogen-containing mycotoxins. Gas chromatography has been used for determination (with or without derivatization) of several nitrogen-containing mycotoxins and/or their degradation products. Immunochemical techniques, in particular ELISA are available for only a very limited number of NM (e.g. ochratoxin A). Numerous methods for determination of ochratoxin A in feeds, grains, animal products and other foodstuffs have been developed. Methods for which recoveries have been carried out on spiked samples are also available for several other NM.

Nitrogen-containing derivatives of 1,4-naphthoquinone synthesized in the form of donor-acceptor autocomplexes, may serve as highly effective antioxidative agents exhibiting their properties both in microheterogeneous medium (water-micellar Tween 80 solution) and in enzymatic and nonenzymatic oxidation of lipids in mitochondria. Some of these complexes studied, where intramolecular transfer of a charge occurred during nonenzymatic oxidation in mitochondria, were only slightly less effective in the antioxidant activity as compared with the standard antioxidant ionol. Distinct increase in the antioxidant activity of the most substances studied was detected in presence of reductases participating in mitochondrial chains of electron transfer and two of these drugs proved to be more effective as compared with menadione and ionol. The data obtained are of importance for pharmacological prognosis of these new biologically active substances efficiency.

Optimization of the Kjeldahl method for determination of total nitrogen in the objects of microbial synthesis was performed in regard to biomass of the benzylpenicillin-producing culture, activated sludge and certain organic compounds. Mathematical processing of the data was carried out, which showed that the difference in the mean values for the five tested conditions of mineralization was insignificant. The method is useful in assaying the final and intermediate products as well as the waste in biotechnological production.

It has been shown that gaseous oxygen produced in a system containing a solid polymer electrolyte from distilled water and two water samples containing different concentrations of chemicals meets on the whole USSR Standard 5583-78 and iso standard 2046. This oxygen underwent toxic evaluations on 60 white noninbred male rats. When mixed with gaseous nitrogen (1:4), electrolytically produced oxygen exerted no unfavorable effects on the animals.

The rate of molecular nitrogen fixation was determined in bottom grounds of three Estonian lakes and the Rybinsk water reservoir in the summer of 1977--1978. Certain species of nitrogen fixing bacteria were found to be confined to lakes of certain trophic type. Ecological niches with the mass growth of Clostridium pasteurianum, Azomonas agilis and Clostridium butyricum were detected in the sediments of eutrophic lakes. Ecological niches of Az. insignis and Cl. acetobutylicum occur in polyhumic lakes. Ecological niches for the nitrogen fixing microaerophilic organisms Methylosinus trichosporium, M. sporium and Mycobacterium flavum can be found in the sediments of water reservoirs of any trophic type. The important ecological factors which favour the growth of microflora with a high rate of molecular nitrogen fixation in bottom grounds are as follows: a sufficiently high temperature, a weakly alkaline reaction, the presence of oxygen in the water near the bottom, and the ratio of organic carbon to total nitrogen about 10--11. The destruction of organic substances in such sediments involves both aerobic and anaerobic microflora, and Cl. butyricum is abundant among nitrogen fixing microorganisms.

The authors report data about the contents of non-protein nitrogen, bound and soluble nitrogen, free amino acids, monocarbonyl compounds and volatile fatty acids as well as about the sum of dinitrophenylhydrazine derivatives of carbonyl compounds and about the microflora. The greatest differences between experimental and control cheeses (produced with rennin) in the contents of the above-mentioned constituents were observed within the first 30 days. On day 60 of experimentation, these differences had smoothed down. It is concluded that a I:I mixture of porcine pepsin and rennin may be used for the production of small medium hard cheeses without impairing their quality of nutritive value.

The nitrogen metabolism in rats with toxic affection of the liver caused by administration of CCl4 was studied as affected by the amino acid mixture moriamine S-2. It is established that with toxic hepatitis the nitrogen metabolism is sharply disturbed, especially during protein deficiency. The following evidences for this fact: a rise in the depth of the nitrogen negative balance, an increase in the intensity of amine nitrogen and ammonia excretion with urea as well as an increase in the amount of amine nitrogen in blood and tissues with a simultaneous decrease in the content of protein. The parenteral administration of the amino acid mixture for eight days to the animals with a toxic affection of the liver is more effective when nitrogen preparation is combined with the group B vitamin, vitamin C, insulin, nerobolyl and sirepar.

In patients with periodontal disease a distinct increase in secretion of salivary acidic and alkaline RNAases was found. The RNAases activity in mixed saliva correlated with the intensity of degradation of periodontal tissues during loss of alveolar layer in aged Wistar rats and the spontaneous periodontal disease in cats. In experiments with golden hamsters salivary RNAase was found to penetrate through mucosa in active form. The purified salivary RNAase inhibited the protein biosynthesis in rabbit gingiva. Intensive atrophic alterations were produced in periodontal tissues of Wistar rats by means of purified salivary RNAase.

A method of instrumental photonuclear activational analysis is developed for estimation of nitrogen, fluorine and phosphorus in bone tissue samples. The irradiation with maximal energy 15.6 MeV, obtained on linear accelerator of electrons LUE-25 RIMR AMN USSR, was used for activation. Estimations were carried out by the relative method with recording the intensity of positron radiation of 13N, 18F and 30P in samples and standards by means of device for gamma-gamma-coincidence. In chosen regimens of the analysis the statistical errors of nitrogen and phosphorus estimation did not esceed 1.5%, of fluorine-5%; the sensitivity of the method for nitrogen was found to be 0.06% for fluorine-0.006%, for phosphorus-0.12%; on analysis of recovery the relative standard deviation in results accounted for nitrogen-5.4%, for fluorine-6.7% for phosphorus 6.2%. Correctness in concentrations of the elements, estimated by the method described, correlated with the data, obtained in activation with reactor neutrons and with 14MeV generator neutrons.

The nitrous composition of meat in 19 species of oceanic sharks and 2 species of rays were analyzed. The meat of these fish species was found to be characterized by a comparatively low protein content, whose amino acids composition proved relatively poor of essential amino acids. The meat of sharks and rays is distinguished by a high level of extractives, whose bulk includes urea and trimethylaminoxide.

A culture medium for the isolation and cultivation of pneumococci, produced in a solid or liquid form and based on raw material unsuitable for use as foodstuff (human placenta), has been developed. The amino acid composition of the medium has been studied. The medium has been found to contain 19 amino acids, to be free from ballast serum proteins and blood, and to ensure the good growth of pneumococci isolated from pathological material, the formation of the normal capsule, as well as active biological properties. The medium has proved to create elective and selective conditions enhancing the effectiveness of investigations and simplifying the isolation of pneumococci in the microbiological examination of patients.

Nitrous metabolism was studied in children of two age groups (from 1 to 6 months and from 7 to 12 months) living in Frunze. Metabolism studies were carried out for 2 days. Subject to study was balance, retention assimilation of nitrogen and the content of urine nitrous fractions; urea, ammonia, creatine and creatinine. Nitrous metabolism in children under one year was characterized by intensive protein turnover under the climatogeographic conditions of the city of Frunze.