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The effect of breed and stage of lactation on the microbiological status of raw milk
37-45Views:700The microbiological quality of the milk is important not only for food safety, but it can also influence the quality of dairy products. The microbiological status of raw cow milk can be influenced by many factors. Our aim was to determine whether there was a difference between the microbiological quality of milk of two different cow breeds (Holstein Friesian and Jersey) kept and milked in the same conditions, and how the microbiological quality of the raw cow milk changed during lactation (beginning, mid, and end). Samples were taken and analysed in July, August and September in 2018 from two dairy farms in Hajdú-Bihar county. During the conducted studies, the total plate count (TPC), the coliform count, the Staphylococcus aureus count and the coagulase-negative Staphylococcus (CNS) count of raw milk samples were determined.
There was no significant difference (P>0.05) between the milk of the Holstein Friesian and Jersey breeds in the case of TPC. However, the mean coliform count of milk samples taken from Holstein Friesian cows was significantly lower (P<0.05) than the mean coliform count of milk samples taken from Jersey cows. S. aureus was detected in one of the twelve milk samples taken from Holstein Friesian cows, and in two of the eleven milk samples taken from Jersey cows. CNS was found in larger amount in milk samples taken from Holstein Friesian cows, and the difference was significant (P<0.05). Both TPC and CNS count were significantly higher (P<0.05) in individual milk samples taken at the end stage of lactation, than in samples taken in the earlier stages of lactation from Farm “A”. However, in the case of Farm “B”, there was no significant difference (P>0.05) in colony counts at different stages of lactation. S. aureus was only present in milk samples that collected from cows, which were at the beginning and middle stages of lactation. Testimg the hemolysin production ability of S. aureus strains isolated from the raw milk samples, only weak hemolysis was observed on blood agar. In case of antibiotic resistance testing, it was found that all strains were susceptible to cefoxitin, chloramphenicol, clindamycin, erythromycin, gentamicin, penicillin G, tetracycline and trimethoprim/sulphamethoxazole.
Based on the results of our studies, staphylococci were detected in a higher amount in the milk of Holstein Friesian cows, and coliform bacteria were detected in a higher number in the milk of Jersey cows. Summing up the results of the milk samples taken from the different stages of lactation in one of the farms, it can be concluded that higher TPC and CNS count could be detected at the end stage of lactation than in the samples taken from the earlier stages of lactation. The fact that at the end of lactation the microorganisms could be detected in a higher colony count may be related to the fact that teats could be damaged during lactation by the milking machine, which increased the chance of imvading the microorganisms into the udder.
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The effect of washing for the shelf-life parameters of spinach (Spinacia oleracea L.)
131-135Views:543Spinach is a very popular green leafy vegetable because of its versatile usage and beneficial for the health. However, spinach may contain several pathogen bacteria: Escherichia coli, Klebsiella spp., Salmonella spp., Enterobacter spp., Citrobacter spp., Shigella spp. and Listeria monocytogenes, which can cause several serious health problems. This study investigates the effects of washing with citric acid for the shelf-life parameters of spinach in comparison to the effect of washing with water and control. Washing of spinach with 0.5% citric acid solution decreased the elasticity of the spinach leaves, as well as the chlorophyll content. On the other hand, the total plate count, as well as the yeast and mold count could be decreased with this treatment, but difference was not detectable at the forth storage day. The fecal indicator E. coli did not change, indicating washing was not effective in this case. Further optimisation of treatment and storage conditions may decrease microbial risk of fresh spinach consumption without decreasing its sensory quality.
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The effect of apoplastic pH on the nutrient uptake
65-71Views:216The pH of soil and rhizosphare –around the roots- determine the mobility and solubility of nutrients. The exudates organic acids of plant able to modify the pH, as well as the microorganisms also take part in mobilization of nutrients. The nutrient solve mostly in mildly acidic and neutral pH. The either assumption of utilization of nutrients is the uptake by roots and of course uptake to the cells to take part in metabolism. The pH of apoplast fluid determines the solubility and uptake of nutrients to the cells.
The aim of this study was to examine the effect of nutrient solution and apoplastic pH together with a bacteria based biofertiliser (Phylazonit MC®) on nutrient uptake and pH of apoplast fluid in case of nutrient solution grown plants in laboratory experiment. According to my results, the bicarbonate increased the pH of nutrient solution in due to influence the solubility and uptake of nutrients. The given bicarbonate to the nutrient solution and infiltrated into the apoplazma also modified the pH of the apoplast fluid of the test plants. The effect of bicarbonate and biofertilizer were different on the pH of the apoplast fluid and nutrient solution in nutrient solution experiment. -
Does the Hooded Crow (Corvus cornix) harbour vancomycin-resistant enterococci in Hungary?
5-8Views:433Vancomycin resistant enterococci (VRE) are high priority nosocomial bacteria with a potential for zoonotic transmission. Thus, its emergence outside health establishments is a major concern. In order to study the prevalence of VRE in wildlife, we collected 221 faecal samples from free-ranging Hooded Crow (Corvus cornix) from urban and rural habitats in Hungary, from March to August 2020. The screening for resistant enterococci was done using bile esculin azide (BEA) agar supplemented with Vancomycin, specific to the screening of VRE. None of the samples from either habitat types yielded VRE. It seems that Hooded Crows from Hungary do not necessarily constitute a reservoir of VREs at present. Nonetheless, a continuous surveillance of VRE in wildlife would be judicious.
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Production of novel fermented milks
303-305Views:287The objective of this research was to test the influence of various natural substances on acid production, growth, and viability of characteristic microorganisms in yogurt and probiotic fermented dairy foods. Oligofructose, inulin, honey, and the dried biomass of Spirulina (Arthrospira) platensis were found to stimulate the growth rate and acid production activity of the major thermophilic diary cultures tested and, in addition to this, the presence of the aforementioned substrates also improved the survival of starter bacteria in fermented milk products during storage. The reduced production time of cultured milks resulted in increased production efficiency. The stimulatory and/or protective effect of oligofructose,
inulin, honey, and Spirulina on Bifidobacterium spp. is probably the most important finding of this study because bifidobacteria do not grow well in milk and they have low survival rates in conventional fermented milks. Some of the bioactive substances tested were also capable of exerting an antifungal effect on spoilage yeasts and molds, and improving the nutritional and sensory properties of the final product, thus providing a new opportunity for manufacture of functional fermented dairy foods. -
Pre-treatment of wastes containing keratin in industrial conditions
59-64Views:552The aim of the research was a development of a featherdegradation technology in industrial circumstances. During the experiments we determined the parameters of the critical environmental and technological limitation factors. Because of the high keratin-content the degradation (and composting) of the feather is difficult. With the developed technology huge mass of feather can be used fast and easily in biogas production and in the adjustment of the optimal element ratio of biomass. The industrial experiments were implemented in a 6m3 heatable double-walled
tank with stirring-shovels and aeration-system. The degradation process was followed with extinction measurements.
According to the experiments that were done the best results were given at the case which was heat-treated at 70°C, was injected with 1% bacteria concentration, and where 1:3 feather:water ratio was set if we consider the effectiveness of degradation and the hydraulical retention time. -
Utilization and examination of red, elemental selenium nano spheres, produced by fermentation technology, in animal tests
245-247Views:349In our experiments we tested the toxicity of Nano-Se and LactoMicroSel® compared with other organic and inorganic selenium forms, in case of a subakut animal test. We produced the Nano-Se and LactoMicroSel® by probiotic lactic acid bacteria in our laboratory. (Prokisch et al., 2010; Eszenyi et al., 2011). We mixed the inorganic selenium forms, selenite and selenate, the organic form, Sel-Plex® and our products, Nano-Se and LactoMicroSel® into the standard food of laboratory mice and we fed them for two consecutive weeks. After the extermination we observed mortality, the change of body mass,and measured the blood antioxidant capacity with FRAP method.
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The Effect of the Mineral Content of the Leg-Horn and the Age of Sheep on the Mechanical Parameters of the Horn
42-45Views:184Species and individual animals with hard leg-horn have higher resistance against foot diseases. The reason for this is the fact, that bacteria can penetrate the hard leg-horn with more difficulty than the soft leg-horn, and in this way it is also more difficult for them to cause an illness. From among the mechanical parameters of the leg-horn the P = 0.1% negative linear correlation between the hardness and the water contents of the horn is significant. There is a positive linear correlation between the shock resistance and the water contents of the leg-horn. In the case of air-dry horn (with less than 8% water contents) there is a positive linear correlation between the Ca- and Zn contents as well as the Ca:P ratio and the hardness of the horn. The results suggest that the wider the Ca:P ratio of the horn, the harder the horn is, while the water content is the same. The leg-horn of the Hungarian Merino ewes have larger Ca contents and wider Ca:P ratio than juvenile animals have. This is why the juvenile animals with a softer leg-horn can be more susceptive to foot diseases than the older animals.
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Effect of bacteria containing bio-fertilizer on Cd-tolerance of corn and sunflower seedlings in nutrient solution
15-21Views:205Bio-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.
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Dietary fibre prevalence and its role in human nutrition
9-13Views:455The 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.