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Kraków, Poland

Dulinski R.,University Rolniczy akowie
Zywnosc. Nauka. Technologia. Jakosc/Food. Science Technology. Quality | Year: 2010

Vitamins are widely applied to produce food (including dietary supplements), pharmaceuticals, feed-stuffs, and, also, as components of cosmetics. On the industrial scale, the majority of vitamins are produced using methods of chemical synthesis or through the extraction of natural substances, but, in many cases, those processes consume high amounts of energy and generate high waste disposal and waste utilization costs. Those arguments were the spur for searching for options to replace syntheses with biotechno-logical processes beginning from the use of micro-organisms in the selected bio-transformations (vitamin C) to the complete microbiological synthesis with engineered strains, for example in the case of vitamin B12. An alternative is the production of raw materials of plants with an increased content of vitamins by the metabolic design of pathways of their biosynthesis, or using them as bio-reactors, the so called 'phy-topharming' (vitamins A and E). This paper presents some selected aspects relating to the biotechnologi-cal production of vitamins and to the selection of transgenic organisms for their production. Source

Oat starch differs in its properties from other commercially produced starch types. It is characterized by small sizes of granules and a high content of lipid substances impacting its properties to a substantial extent. The objective of the research project undertaken was to determine some selected physical-chemical properties of starches extracted from the Polish varieties of naked oats. The determined parameters were: size of granules (determined using 'VEM', i.e. a video enhanced microscopy and an image analysis), contents of amylase and lipids, water binding capacity (WBC) and solubility, and pasting profile of 5% water based suspensions. The sizes of starch granules ranged from 1.3 to 13.4 μm, and the average diameter was 6.4 μm. The average content of lipids in the starches investigated was 1.23 %, and of amylase: 15.66 %. The starches analyzed were characterized by a low water absorption and solubility, as well as by an atypical profile of pasting. Source

Study was performed in multi-species stand located in the Świȩtokrzyski National Park (central Poland). Silver fir, Norway spruce and Scots pine trees that grew in a uniform habitat conditions were selected. The trees showed the differences and similarities of changes of the size of radial increment, which result from species-specific sensitivity to selected meteorological elements. Source

The study describes allometric relationships between stand density and tree dimensions in birch stands on post-agricultural lands. The research material consisted of measurements carried out on 120 sample plots located in birch stands on post-agricultural lands of Central Poland. The investigated relationship was analyzed using ordinary least squares (OLS), dynamical formulation of allometric function (DFA), stochastic frontier production function (SFF) as well as quantile regression (QR) methods. Similar effects of modeling maximum density were obtained as a result of applying FFP and QR methods with 0.9 quantile. SFF was found to be the most adequate method for modeling maximum density. © 2014, Polish Forest Society. All rights reserved. Source

The aim of the study was to determine the effect of temperature and humidity on colonization of cambio-xylophagous insects on Norway spruce branches in relation to the place and method of slash utilization. Analyzed branches were infested by eight species of cambiophagous and two species of cambioxylophagous, whereas the material utilization method does not substantially influence the entomofauna species composition. The most numerous were: Pityogenes chalcographus, Ips amitinus, Dryocoetes autographus and Pityophthorus pityographus. The branches treatment was a factor contributing significantly to the infestation intensity by P. chalcographus and I. amitinus, reaching a higher density of galleries on the branches spreading disorderly on the forest floor than collected in the piles. Moreover, it was found that the location of branches inside the pile determines their attractiveness to hygrophilous species with a minor economic importance. Significant differences in temperature and relative humidity inside the piles and the surrounding branches scattered disorderly on the surface during the growing season indicate that this may be an important factor influencing logging residues left in the forest infestation intensity by bark beetles. © 2014, Polish Forest Society. All rights reserved. Source

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