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Overview of the evolutionary history and the role in citric acid production of alternative oxidase
83-88Views:293All 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.
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Different ideas on the pathogenesis and treatment of swine edema-disease
45-48Views:364Although 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.
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The potential use of Pediococcus spp. probiotic in aquaculture: A review
99-106Views:606Aquaculture production has significantly increased over the previous few decades. However, antibiotics have been implemented regularly and extensively to overcome outbreaks of pathogens in aquaculture to cover the human needs for animal protein, leading to the appearance of resistant strains that may cause serious damages in the environment and also human health. In the last few years, the implementation of probiotics as an alternative technique to antibiotics use in fish production has achieved promising results in aquaculture due to their beneficial impact on fish health and growth performance. Among different types of probiotics, the Pediococcus spp. bacteria stand out as a promising probiotic for their beneficial impact to aquaculture. Thus, the current study has been conducted to give an overview about the interactions between Pediococcus spp. and aquaculture. In addition, this review highlights the role of Pediococcus spp in promoting growth performance, improving feed conversion ratios and the intestinal architecture, enhancing the immune response and inhibiting fish pathogens, thereby preventing or at least reducing the use of antibiotics. Practical use of Pediococcus spp. probiotic in aquaculture as feed additives through selected case studies is also considered.
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Presence, feeding and health status of collared doves (Streptopelia decaocto Friv. 1838) on animal breeding farms
49-54Views:309In the course of our examinations we were determining the gender of collared doves (Streptopelia decaocto) feeding at animal breeding farms by biometric data. We were estimated their nourishment and necropsies were carried out.
We compared the results of the nutrition analysis with similar data of collard doves feeding at agricultural areas.
We analyzed the crop and gizzard content and recorded the body proportions of collard doves that were captured between December of 2004 and August 2005. In the course of the necropsy examinations we did parasitological, bacteriological examinations as well as examinations for the detection of Newcastle disease. In the course of the gender analysis of the collard doves that were collected at animal breeding farms, both the wing length and the length of the third quill-feather has shown a significantly greater value in the case of males (p>0.05).
From the orts found in the crop and gizzard it has been stated that the feed consumed the most was corn (80.77% m%). The collared doves consumed much less other cereal seeds (wheat 0.82%, barley 1.26%).
In the course of the necropsy examinations done in the Veterinary Institute of Debrecen, the birds proved to be free of parasites, and the results of the Salmonella and Newcastle disease analysis were negative as well. E. coli bacteria had been detected in the liver of not more than three birds. -
The effect of lead and copper heavy metal salts on soil microorganisms under laboratory circumstances
55-59Views:358he 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.
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The effect of wet compost extract on the root tubers of green pea
51-54Views:307Nitrogen 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. -
Risk effects of the spread route of mycotoxins
90-95Views:499In Hungary the mycotoxin is a great problem, because there are many natural toxins in wheat and maize. These cereals can be found on
considerable proportion of the country’s sowing area, and they are deterministic food for the population. The direct human and animal
utilization of the contaminated cereals mean a serious risk in the food chain. In Hungary’s climate the soil is contaminated with pathogen
moulds, particularly Fusarium species, which increase by respective temperature and moisture content in cereals. The Fusarium can
decrease the quality of the wheat in different ways: decrease the germination capability and cause visible discoloration and appearance of
mould, reduces the dry material and nutrient content of the grain. From the toxins produced by the Fusarium genus, the trichotecene (T-2,
HT-2, deoxinivalenol, nivalenol, diacetoxyscxirpenol, Fusarenon-X) and the estrogenic zearalenon (F-2) are the most common in Hungary.
The fumonisins (FB1, FB2, FB3) first identified in 1988, relatively newly discovered, are also important. Major proportion of mycotoxins in a
healthy organization is metabolized by the enzyme system of liver and intestinal bacteria. The toxicity is reduced or even leaves off.
However, more toxic and biologically active compounds can be formed. For the reduction of mycotoxin-contamination several possibilities
are available in the case of storage, processing and feeding. -
Evaluation of reaction to plant density of sunflower hybrids by regression and Kang’s stability analysis
101-109Views:340The world production area and the total production of sunflower has significantly been growing. The harvested yield was 23.4 and 21.1 million ha in 2005 and 2001, respectively. The total sunflower seed production has also unexpectedly increased.
Although sunflower is produced on lower quality soils in Hungary, in 2005 the average harvested yield was 2.43 t ha-1, which was the highest in the world.
Sunflower is a typical commercial plant and fits well in the crop structure. Since in terms of acreage the most significant crops are corn and cereals, the partial monoculture cultivation cannot be avoided. Sunflower production is a way to eliminate this problem, therefore it has an important role both in cultivation and ecological points of view.
Accordingly, sunflower has an important role in reducing the monoculture cultivation of some plants, as well as increasing biodiversity. Sunflower well adapts to Hungary’s climatic conditions and its production is easily practicable in our country.
The reaction of sunflower hybrids on crop density change is different. Some hybrids are more some are less sensitive to this parameter. In different crop years, the crop density optimums of the different genotypes are also different. In Hungary, the yield and quality is primarily determined by fungal infections, while viruses and bacteria are less important.
The research was conducted at the Látókép farm and Regional Research Institute of the University of Debrecen, Centre of Agricultural Sciences. The research institute is situated by Road 33,15 km from Debrecen in the Hajdúság. The duration of the experiment was seven years, 10 hybrids were examined in each year.
Two hybrids used every year, Aréna/PR and Alexandra/PR hybrids were tested by Kang’s stability analysis. We found that Alexandra/PR was most balanced at every levels of crop density. Both hybrids performed most stable yield at 65000 ha-1 crop density level and less balanced at 35000 ha-1 crop density level. As a result of improved environmental conditions, the yield increase of Aréna/PR was higher than that of Alexandra/PR.
Our regression analysis found that the maximum yield of Lympil, Louidor, Hysun 321, PR63A82 and PR64A63 hybrids were harvested at 47000-60000 plant ha-1 crop density level. The statistical analysis showed that the highest yield was harvested from Lympil and Hysun 321. As regards the crop yield, the most stable hybrids were Louidor and Lympil. The optimum crop density interval of Rigasol/PR and Larisol (58000 plant ha-1) was wider than that of Diabolo (46000 plant ha-1). The maximum yield of Larisol was higher at the optimal crop density level. As regards yield, Diabol was the most stable hybrid.
The statistical analysis on the stability of the yield of Alexandra/PR and Aréna/PR showed that Aréna/PR is more stable, and its optimal crop density level is lower than that of Alexandra/PR. -
The examination of presumed Escherichia coli count of raw milk samples on several milk production farms
31-37Views:531For dairy farms, it is of great importance to insure the appropriate hygienic status of milk and to examine it regularly. Escherichia coli, belonging to the coliform bacteria type of, is a good indicator of contamination, and therefore suitable for characterising the hygienic condition of milk production.
The aim of our research was to examine the connection between the Escherichi coli count in bulk tank milk and housing and milking technologies of different-sizes farms. We examined the relation using various statistical methods.
Analysing the connection between the E. coli count and the farm size we found no significant difference between the farms. On the basis of the mean values of the E. coli count, we can say that the hygienic conditions are appropriate for mid-sized farms, and tolerable for large farms. We found differences in the hygienic status among the small farms. Half of the eight small farms, had no adequate hygiene. The results of the analysis of the quality categories show that the probability of inadequate quality milk was the largest on small farms (37.5%).
Comparing the various housing and milking methods with each other, there were numerical differences in the E. coli count, but these differences were not significant. We got higher E. coli count values on those farms using tied stall barn and bucket milking installation. The reason for this could be that in cases of farms using bucket milking installation, it is harder to meet the requirements.
After forming groups by farm size, housing and milking methods, we found that the E. coli counts are adequate on mid-size farms using various housing and milking methods; and tolerable on those large farms using loose housing stable and a milking parlour. At the same time, we found inadequate E. coli counts on the smaller farms using tied stall barns and bucket milking installation.
The results show that if there is suitable attention, independent of farm size, housing and milking procedure, it is possible to produce milk with low E. coli counts, and to insure appropriate hygienic conditions.
Further detailed examinations are needed to decide which factors of housing and milking technologies influence the E. coli count of bulk tank milk. -
Definition antioxidant activity of selenium-enriched food sprout, as well as their microbiological analysis
25-30Views:606In this present study, we prepared selenium-enriched food sprouts, where the antioxidant capacity was analysed, we also determined their microbiological status. We took into account the fact, we choose micronutrients to our treatment, that selenium can be delivered to the body by a small amount with the most widely consumed food.
We focused during our research to determine that the increasing concentrations of selenium treatment, in which we used sprouts, knowing fully well that it has an impact on aboriginal antioxidant capacity of sprouts, which is mainly due to high vitamin content of sprouts.
Furthermore, we think it is important to make microbiological analysis, because germination conditions, for example temperature, pH, all this will create an ideal environment for the growth of microorganisms. So we had goal to determine, how the used selenium concentration affect the total plate count, coliform bacteria count and Staphylococcus aureus count of sprouts.
We determined the aboriginal water-soluble and lipid-soluble antioxidant capacity of sprout with the PHOTOCHEM chemiluminometer and we applied pour plate technique for the mapping of the mycrobiological state of sprouts.
Experimental results are evaluated, we state that increasing concentrations of selenite or selenate treatment, is primarily water-soluble antioxidant capacity of sprouts was affected. The water-soluble antioxidant capacity of wheat sprout was much higher than the measured values in pea sprout, this may be linked to what we measured. That is much higher ascorbic acid content in case of wheat sprout, which is well known as one of the most important antioxidant properties compounds of wheat sprout.
We conclude from the results of the microbiological, that the highest concentrations of selenite or selenate treatment has a relative significant anti-microbial effect in case of wheat sprouts. Coliform and total plate count showed no clear decreasing tendency, although the values of treatments in both cases obtained were below the control values.