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The aim of this study was to assess the possibility of using biological and biochemical parameters in the evaluation of forest soil quality and changes caused by land use. The study attempted to determine a relationship between the enzymatic activity of soil, the number of earthworms and soil physico-chemical properties. The study was carried out in central Poland in adjoining Forest Districts (Przedbórz and Smardzewice). In soil samples taken from 12 research plots, basic physico-chemical properties, enzyme activity (dehydrogenase, urease) and density and biomass of earthworms were examined. Enzyme activity showed a large diversity within the forest site types studied. The correlations between the activity of the enzymes studied and C/N ratio indicated considerable importance of these enzymes in metabolism of essential elements of organic matter of forest soils. Urease and dehydrogenase activity and earthworm number showed susceptibility to soil pH, which confirmed relationships between enzyme activity and abundance of earthworms and soil pH in H2O and KCl.
The API 20E test and standard methods were applied to examine biochemical features of P. multocida strains. All tested isolates decomposed glucose, mannitol and saccharose. Sorbitol and arabinose were fermented by 82% and 43% of the strains, respectively. Xylose, trehalose, and dulcitol were fermented by 30%, 13% and 4% of isolates, respectively. All the tested strains produced catalase, ornithine decarboxylase, cytochrome-oxidase, indole, and reduced nitrates to nitrites. Moreover, the strains did not reveal motility and did not grow on MacConkey agar and failed to ferment maltose. Our findings enabled the recognition of ten distinct biochemical types, termed biovars I to X, and permitted the assignation of the strains into 3 subspecies. Of the isolates tested, 78% were identified as P. multocida subsp. multocida, 8.1 % as P. multocida subsp. septica, and 4% as P. multocida subsp. gallicida according to Mutters et al. ( 12). On the other hand, 9.7% of the strains were not classified as one of the three subspecies.
The influence of iodine-iodide solution on (he biochemical and immunological properties of human thyroglobulin (hTg) were studied. Human Tg preincubated with the iodine-iodide solution is split to small molecular mass fragments after disulphide bridge reduction with dithiothreitol. The peptide bond cleavage by iodine pretreatment and reduction is possibly linked with the coupling reaction of diiodotyrosyl residues. Pretreatment of hTg with iodine-iodide solution at 1 -10 |iM decreased the binding of autoantibodies to hTg. The iodine-iodide induced inactivation of hTg autoepitopes is pH dependent and is possibly caused by iodination of tyrosyl residues present in the epitope structure.
In this experiment the effects of lead and lead-free petrol applied at the following doses of: 0, 2, 4 and 6 cm(3) . kg(-1) of soil on growth and development of triticale and biochemical properties of the soil were studied. For detoxication of petrol organic amendment with barley straw was applied. The experiment was performed in two experimental series with and without triticale cover. It was found that soil contamination by petrol adversely affected growth and development of tested crops. Barley straw appeared to be ineffective in detoxication of the contaminated soil. Lead and lead-free petrol (irrespective of plant cover and application of straw) adversely affected activity of soil dehydrogenases and urease. Straw application and growing of triticale positively affected biochemical properties of the soil. These positive effects were diminished by petrol, irrespective of the lead addition. Biochemical index of soil fertility calculated on the basis of enzymatic activity and carbon content was negatively correlated with the level of soil contamination by petrol and positively with triticale yield.
This study was conducted to determine the phy- sical and biochemical properties of guava, sapota, and papaya. The physical properties studied were: dimensions, shell ratio, surface area, bulk and true density, porosity, sphericity, packing coeffi- cient, aspect ratio, and roundness index. The specific heat at various mass fractions, biochemical properties like pH, titratable acidity, total soluble solids, and colour analysis were studied for fruit pulps. The viscosity of fruits was studied at various mass fractions. The high sphericity of guava and sapota indicated that those fruits had high rolling capability, which is an important factor for designing hoppers. Bioch emical analysis showed that sapota was the sweetest fruit amongst the three studied.
Starter consisting of L. reuteri, L. casei and L. gasseri was used either separate or mixed with L. bulgaricus and S. thermophilus to produce probiotic Ras cheese. In the control cheese use was made of a starter consisting of L. bulgaricus and S. thermophilus. The first starter produced cheese containing more soluble nitrogen, essential and non-essential amino acids and a and b-galactosidase, amino peptidase and dipeptidase enzymes than the cheese of the mixed starter. The control cheese contained less of both starters than the cheeses. This was manifested in more protein breakdown appearing in more intense bands on electrophoresis electrophoregram. Both starters inhibited the growth of coliform, staphylococcus bacteria, yeast and molds on their cheeses. Moreover, both starters could help in lactose intolerance.
Biochemical properties, serotype classification and drug resistance were evaluated in 41 Pasteurella multocida strains isolated from cattle suffering from haemorrhagic septicaemia (HS). The API 20E test and standard methods were used to examine selected biochemical features of the strains. The results permitted classifying the isolates as P. multocida subspecies multocida strains. All the isolates revealed both capsular antigen B (by Carter) and the somatic antigen specific to the serotype 2 (by Heddleston). A weak positive reaction with the specific serum to serotype 5 was noticed. Haemorrhagic septicaemia was serologically confirmed for the first time in Poland. The isolates examined were highly sensitive to antibiotics and chemiotherapeutics. A distinct resistance was found in the case of streptomycin; several strains were also resistant to neomycin, gentamycin, erythromycin or sulphonamides.
The effect of soil contamination with copper on soil biochemical properties and oat yields was assessed in a pot experiment. Copper was applied alone or in combination with other heavy metals. The study was conducted on samples of brown soil consisting of heavy loamy sand and brown soil developed from light silty clay. On days 28 and 56 of the experiment the following were determined: activity of dehydrogenases, urease, acid phosphatase and alkaline phosphatase in soil as well as oat yields. Contamination of soil with copper, zinc, nickel, lead, cadmium and chromium in concentrations of 50 mg kg-1 was found to have a negative influence on the activity of dehydrogenases, urease, acid phospha- tase, alkaline phosphatase and yield of oats. The soil enzymes can be arranged in terms of their sensitivity to heavy metals as follows: dehydrogenases > urease > alkaline phosphatase > acid phosphatase. Higher activity of dehydrogenases was determined in brown soil developed from heavy loamy sand, while urease, acid phosphatase and alkaline phosphatase were more active in brown soil formed from light silty clay. The contamination of copper with other heavy metals was inhibited in heavy loamy sand more than in light silty clay.
A field experiment has been undertaken to assay the effect of Triflurotox 250 EC applied in the rates of 0, 1.5, 3.0, 4.5, 6.9, 9.0 and 12.0 mm3 kg-1 soil on the growth and development of spring rape and white mustard and on the biochemical characteristics of the soil. The trials were conducted on leached brown soil formed from light clay silty sand of pH equal to 5.8 in 1 M KCl. The biochemical analyses were made 7 days after the experiment was established and in the flowering phase of the plants. The results proved that Triflurotox 250 EC applied in the rates varying from 1.5 to 12 mm3 kg-1 soil had an adverse effect on the activity of dehydrogenases, acid phosphatase and alkaline phosphatase. Spring rape and white mustard were vulnerable to high concentrations of Triflurotox. The yields were negatively correlated with the herbicide rate. Potential biochemical soil activity index computed from the activities of dehydrogenases, urease, acid phosphatase and alakline phosphatase as well as the organic carbon content in the soil was negatively correlated with the Triflurotox 250 EC concentration in the soil and positively correlated with the spring rape and white mustard yields. Base saturation of soils was positively correlated with the Triflurotox concentration, in contrast to hydrolytic acidity and total exchange capacity, which were negatively correlated with the herbicide rates.
The aim of the study was to determine how adenine affected biological proprieties of soil. The performance of this precursor cytokinine was tested in a pot trial. The question posed was whether it was possible to improve efficacy of adenine by enlarging populations of bacteria from Azotobacter species in soil. The experiment was carried out on proper brown soil, formed from dust clay sand with pHKCl 6,9. Pots were filled with 3.2 kg of soil. The investigations were performed in two series: with and without addition Azotobacterin to soil. Tow rates of nitrogen fertilisation: 0 and 50 mg N·kg-1 of soil were applied in test. Adenine was applied in the following quantities: 0; 5; 10 and 15 mg·kg-1 of soil. Radish, 6 plants per pot, was the test plant. It was confirmed that the adenine had a significant effect on growth and development of radish. It positively affected microbiological and the biochemical proprieties of soil. The counts of total oligotrophic bacteria, oligotrophic sporulation bacteria, total copiotrophic bacteria, copiotrophic sporulation bacteria, ammonifying bacteria, immobilizing bacteria, celulolytic bacteria, Azotobacter sp., Artrobacter sp. and Pseudomonas sp. were increased, and the number of fungi diminished. Adenine also stimulated activities of dehydrogenase, urease and alkaline phosphatase, although it depressed the activity of acid phosphatase. The inoculation with bacteria from Azotobacter species applied to soil failed to improve efficacy of adenine. Nevertheless, it increased counts of these bacteria, which had a beneficial influence on the development of oligotrophic bacteria, immobilizing bacteria, celulolytic bacteria and actinomyces, while negatively affecting fungi, ammonifying bacteria and Arthrobacter.
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