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Cracow, Poland

The Agricultural University of Kraków , located in Kraków, Poland, became an independent university by decree of the Council of Ministers as of 28 September 1972. Formerly, it was known as the Higher College of Agriculture of the Jagiellonian University, as well as other names, since its establishment in 1890. Wikipedia.

Tarko T.,Agricultural University of Krakow
Roczniki Państwowego Zakładu Higieny | Year: 2013

Phenolic compounds are a group of key plant metabolites found abundantly in fruit and vegetables. Because of their antioxidant properties, they play a significant role in preventing various degenerative illnesses, tumours or cardiovascular disease. In nature, they are present in foods mainly as esters, glycosides and polymers which need to undergo enzymatic hydrolysis in the digestive tract or by the gut microflora before becoming absorbed. The biological properties of these phenolic compounds undergoing this degradation, are thus governed by their absorption as well as metabolism. Many methods are used to assess the rates and the degrees to which these substances are digested and absorbed, both in vivo and in vitro ones, where the former are the most reliable, although they suffer from various limitations. For this reason, many in vitro models have now arisen to simulate the function of human digestion in the attempt to faithfully re-create real-life conditions. Mechanisms of polyphenols absorption have been principally studied by intestinal epithelial cell models, in particular, those using the Caco-2 cell line. Source

The levels of vitamin C, polyphenol constituents and Trolox equivalent antioxidant activity (TEAC) were analyzed in raw kale leaves, blanched leaves and dried leaves obtained using air and freeze-drying methods. 100 g of raw kale leaves contained 683 mg vitamin C and 2236 mg polyphenols (identified using the HPLC method); the level of antioxidative activity was 71 μM Trolox/1 g dry matter. Compared with the raw material, blanching before drying brought about significant decreases of 15% in vitamin C, 32% in polyphenols and13% in TEAC. After 12-month storage, air-dried material retained 30-37% polyphenols; 43-57% vitamin C; and 41-50% of the initial TEAC level; the corresponding values for freeze-dried material were 40-47%; 50-65% and 54-66% depending on the type of sample. Freeze-dried kale leaves contained higher levels of antioxidants than air-dried material: polyphenols, vitamin C and TEAC were respectively 36%, 15%and 33% higher. © 2011 Elsevier Ltd. Source

The paper presents the results of microwave irradiation and conventional heating of honey. These two kinds of thermal treatment result in the formation of 5-hydroxymethyl-2-furfural (HMF), and changes in the antioxidant potential of honeys, which were studied as well. Four types of honey (honeydew, lime, acacia, buckwheat) were analyzed. Honey samples were subjected to conventional heating in a water bath (WB) at 90 °C up to 60 min or to the action of a microwave field (MW) with constant power of 1.26 W/g of the sample up to 6 min. Changes in the antioxidant capacity of honeys were measured as a percentage of free radical (ABTṠ+ and DPPḢ) scavenging ability. Changes in the total polyphenols content (TPC) (equivalents of gallic acid mg/100 g of honey) were also determined. Formation of HMF in honey treated with a microwave field was faster in comparison with the conventional process. Changes in the antioxidant properties of honey subjected to thermal or microwave processing might have been botanical origin dependent. © 2013 Elsevier Ltd. Source

Socha J.,Agricultural University of Krakow
Forest Ecology and Management | Year: 2012

The aim of this study was to estimate the long-term effect of wetland drainage on the productivity of Scots pine stands in Poland. Data were obtained from the forested area of the Niepolomice Forest District, which was drained in 1964-1968. To describe the long-term changes in site productivity, a local site index model was developed. The effect of drainage depended primarily on the age of the stand at the time of drainage. A positive growth response (i.e., an increase in height) was observed in stands that were younger than 45-50years at the time of drainage, with younger stands showing stronger responses. Drainage caused an increase in the site productivity of young stands that can be expressed as a change of 5.4m in site index. For fully stocked stands, the average effect of drainage expressed as the predicted increase in total wood production at age 100years was estimated to be approximately 200m 3ha -1 (25%) in those stands planted after drainage. The predicted increase in the total volume of production at total stand age 100years for stands that were 30years old at the time of drainage was estimated to be approximately 125m 3ha -1 (15%). For stands that were 40years old at the time of drainage, the predicted increase in volume production was approximately 50m 3ha -1 (6%). Stands older than 50years at the time of drainage were assumed to be unaffected. © 2012 Elsevier B.V.. Source

Sechman A.,Agricultural University of Krakow
General and Comparative Endocrinology | Year: 2013

In all vertebrates, including birds, the normal development of the ovary and ovarian follicles is under the regulatory influence of hormones produced by the reproductive axis. In recent years, it has become clear that in birds an adequate level of thyroid hormones (THs), i.e. thyroxine (T4) and triiodothyronine (T3), in blood circulation is of primary importance for normal female reproductive functions. In avian species, characterized by seasonal reproduction, THs are involved in the photoperiodic regulation of reproduction acting at the mediobasal hypothalamus. In domestic fowl, where the seasonality of reproduction has been eliminated, the role of THs in ovarian function is not fully elucidated. Recent studies have revealed that ovarian follicles of the laying hen express mRNAs of TH nuclear receptors (TRα and TRβ0) as well as integrin (αVβ3) plasma membrane receptors, indicating genomic and nongenomic action of THs in the chicken ovary. In vivo experiments carried out on laying hens have showed that the bolus injection of T3 decreases levels of luteinizing hormone (LH) and estradiol (E2) in blood, and a hyperthyroid state evoked by administration of T3 for few days diminishes LH, E2 and progesterone (P4) levels, reduces the weight of the ovary, induces atresia of preovulatory follicles and eventually causes stoppage of egg laying. In vitro studies have demonstrated that T3 decreases E2 secretion from white nonhierarchical follicles and the theca layer of yellow preovulatory follicles, while on the other hand, it elevates P4 production from the granulosa layer of these follicles. These effects have been associated with steroidogenic enzyme expression and cyclic AMP synthesis. This review summarizes the current knowledge concerning the role of THs in regulation of steroidogenesis in chicken ovarian follicles. © 2013 Elsevier Inc. Source

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