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  • Overview of the evolutionary history and the role in citric acid production of alternative oxidase
    83-88
    Views:
    144

    All organisms are exposed to countless environmental effects, which influence in a disadvantageous way their life processes. They continuously adapt to the changing conditions and respond to the stress impacts by defence mechanisms. Through different signal transduction pathways they are able to increase or decrease the expression of their genes and consequently modify their metabolic processes. My interest focuses on alternative oxidase (AOX) enzyme whose expression is often increased under biotic and abiotic stress. The so far proven and putative functions of the AOX play a role in the ability of organisms to adapt to different conditions, such as heavy metals accumulation, pathogenic infection, oxidative stress and lack of oxygen or nutrients.

    AOX is a member of the di-iron carboxylate protein family. Members of the di-iron carboxylate protein family are present in all kingdoms of life. They are considered to have ancient origin. It is believed that their sulfide-resistant and oxygen-reducing ability played a role in the survival of organisms during the transition between the anaerobic and the aerobic world. It is assumed that the AOX arose in eukaryotes through a primary endosymbiotic event, and this event made possible the development of mitochondria. Afterwords, vertical inheritance, and secondary and tertiary endosimbiotic events led to its spread among eukaryotes. It is assumed that bacteria obtained AOX by horizontal gene transfer from plants.

    AOX-catalyzed alternative respiration plays an important role in the operation of energy-producing and biosynthesizing system of microorganisms. In these cases, the regeneration of reduced cofactors is an essential condition, and therefore may be rate-limiting for biotechnological processes, including the citric acid production.

  • Effect of bacteria containing bio-fertilizer on Cd-tolerance of corn and sunflower seedlings in nutrient solution
    15-21
    Views:
    82

    Bio-fertilizers promote the nutrition uptake, firstly enhance the baring and mobility of nutrients, on the other hand biofertilizers elevate nutrient uptake in direct way. Although there are a lot of questions about their application in polluted soils. The  cadmium ion is easily collectable and also transportable inside plants. Thus the Cd can get into the food-chain causing public health problems. The cadmium treatment decreases the dry matter accumulation, and the intensity of photosynthesis at the experimental plants, while the treatments with bio-fertilizer increased these parameters. The cadmium accumulated in the roots, the transport to the shoots was low. We came to the conclusion, that –because of the different nutrient-uptake systemthe sunflower took up more cadmium. Using bacterium containing bio-fertilizer the toxic effect of cadmium was moderated. By our experimental results the use of Phylazonit is offered under contaminated conditions.

  • Dietary fibre prevalence and its role in human nutrition
    9-13
    Views:
    249

    The role of dietary fibre and its impact on health is increasing. It is worth noting that their beneficial effects on the body are becoming more widely known, but their consumption is still below the recommended daily intake from food. Dietary fibre, as a class of compounds, includes a mixture of plant carbohydrate polymers, both oligosaccharides and polysaccharides. Dietary fibre has been linked to a number of diseases, as its consumption can reduce the risk of cardiovascular disease and type 2 diabetes. They influence the composition of the bacteria present in the human gut. Consuming the right quantity and quality of dietary fibre can play a role in the prevention of certain types of cancer. Nowadays, it is common to produce various fibre-enriched foods, called functional foods, because of the beneficial effects they have previously had on the body. In the present work we want to give a general description of dietary fibre and its role in the body.

  • Examination of feral pigeon populations at animal breeding farms
    52-56
    Views:
    94

    In the course of our examination, we assessed biometric data that determine gender, we evaluated sexual activity, measured the nourishment and necropsies of two feral pigeon populations feeding and nesting at animal breeding farms. The changes in the body weight of the different genders were significant on both farms (p<0.05).
    The body weight and the crop volume of the birds were not significantly different at the examined farms.
    On both farms, the elemental food source of the birds was the fodder and corn kernels given to cattle, and was supplemented by that of the pigeons living at the Debrecen farm with food from surrounding farms and with other seeds (pea, millet, rye).
    By the examination of the genitals, the birds collected from the Nyírbátor farm showed sexual activity from the beginning of spring, and in the summertime decreasing activity is characteristic, while the pigeons from the Debrecen farm are only active from the summer months. In the course of the examinations in the Veterinary Institute of Debrecen, the birds proved to be free of parasites and the results of the Newcastle disease analysis were negative as well. The bacteriologic analyses showed a different proportion of E.coli, Pasteurella multicoda, haemolysing Staphylococcus bacteria at the two cattle farms. During the examinations for the statement of Salmonellas, this causative agent was stated only in case of birds that spend nights and nested in the town, which allude to human origin. We demonstrated Eimeria oocysts during the parasitological examination of the fecal samples in 5 cases at the Debrecen, and in 1 case at the Nyírbátor farm.

  • The effect of lead and copper heavy metal salts on soil microorganisms under laboratory circumstances
    55-59
    Views:
    163

    he population dynamics of calcareous chernozem soils polluted with different concentrations of lead and copper heavy metal saline solutions was examined.

    The experiment was carried out in the soil biological laboratory of the Institute of Agricultiral Chemistry and Soil Science at DE AGTC MÉK in 2012. For the determination of the concentration of the undiluted stock solutions we multiplied the smallest toxic concentration values of the MSZ 08-1721/1-86 Hungarian standard by forty. The intermediary concentrations of the treatments were produced with adequate dilution of the stock solutions until a dilution level equal to the values of the standard. The statistical evaluation of the data was performed with ANOVA (Analysis of Variance) including the determination of the standard deviation and significant difference. Investigating the effects of the different treatments on the soil microbes we established that both heavy metal saline solutions had a negative effect on the population dynamics of bacteria and microscopic fungi living in the soils. The negative effect of copper – as a potential toxic micro nutrient – turned out to be less strong than the negative effect of the toxic lead. According to our results the correction of the treatment levels is recommended in order to further tolerance examinations and the determination of the tolerance levels.

  • The effect of wet compost extract on the root tubers of green pea
    51-54
    Views:
    155

    Nitrogen plays significant role in the life of plants, it could be the main limiting factor of plant growth. Sustainable plant nutrition pays attention to satisfy the plants’ nutrient demand without chemical fertilizers, e.g. by bounding the atmospheric nitrogen. The nitrogen fixing organizations play important role in supplying plants with nitrogenbecause the N2-fixingbacteria can fix high amounts of nitrogen.
    Many effects of the sewage sludge compost extracts is known in the literature. We studied the effect of sewage sludge compost water extract in laboratory conditions on the growth of Rhizobium spp. isolated from green pea, while in a small plot experiment thepea-Rhizobium symbiosis were studied on sandy soil in the Nyírség region. The extract was produced under aerobic conditions. The compost extract was applied before and/or after sowing. In the laboratory experiments we used the sterile version of extract, in different doses.
    In our work we present the effect of compost water extract on the number of green pea roots nodules, dry weight of the plant and reproduction of the Rhizobium bacteria.

  • Different ideas on the pathogenesis and treatment of swine edema-disease
    45-48
    Views:
    207

    Although literature data associate the reason of swine edema-disease with certain serotypes of Escherichia coli bacteria, the authors assume that the primary cause of edema is more different. Susceptible agents and factors, mostly of feed compound are involved. During the digestion of some feed-origin protein opiate-like metabolites, exorphins arise, simultaneously arrest the release of acetylcholine. Consequences of acetylcholine shortage are spasm of sphincters (mostly pylorus), intestine-dilatation, contraction of bladder-sphincter, and urine retention. The endorphins and exorphins intensify the insulin release from the pancreas, hypoglycemia evolves, which is associated with loss of balance. According to the authors in edema-disease piglet dies because of hypoglycemia.