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111.
The aim of present study was to determine whether chickens’ (broilers Ross 308, n = 180, sex ratio 1:1) diet modification with different doses of grape or pomegranate seed oil will favourable change fatty acids and cholesterol content in selected giblets (liver and heart) or wastes (adipose tissue). It was also verify whether generated changes would make the giblets and wastes more valuable as dietary components or by-products for food industry. From 22 to 42 day of life, five diets were administered to chickens. Control grower diet (CON) contained 5% of soy oil, whereas in the experimental grower diets part of soy oil (1.5% or 2%) was replaced with specific amount of grape or pomegranate seed oil (GRAP 1.5; GRAP 2.0; POM 1.5; POM 2.0 respectively). Fatty acids and cholesterol content were determined with gas chromatography with flame-ionization detection. Pomegranate seed oil improved fatty acids profile more favourably than grape seed oil, which makes it a valuable additive in chickens’ feeding. Abdominal fat of pomegranate seed oil supplemented chickens appeared to be the richest sources of rumenic acid and n3 polyunsaturated fatty acids, which allows to suggest its use in manufacturing of meat products to obtain foodstuffs rich in those essential nutrients. In principal component analysis (PCA), two principal components: PC1 and PC2, which were enough to explain 29.91% of variance of initial variables, allowed to a good separation of chickens fed with both doses of pomegranate seed oil from animals from control and grape seed oil fed groups. Because poultry addresses all nutritional, institutional and consumer requirements, enrichment of giblets in rumenic acid by pomegranate seed oil incorporation into chickens’ diet may provide a valuable dietary source of bioactive fatty acids for consumers, especially of low-income countries.  相似文献   
112.
A stable isotope dilution assay has been developed for quantification of (E)-1-(2,3,6-trimethylphenyl)buta-1,3-diene (4) in wine using a [(2)H(6)]-analogue. Using this method, 4 was found in 96 out of 97 white wines, but in none of 12 red wines analyzed. 4 was found to be most prevalent in Semillon wines, followed by Chardonnay, with Riesling showing the least amount of 4 among these three varieties. 4, like 1,1,6-trimethyldihydronaphthalene (TDN, 3), appears to be formed during the aging process. 4 was found to be unstable in model wine, and in both white and red wine, with the order of stability being model > white > red. In a PVPP-stripped red wine, the rate of degradation of 4 was substantially lessened, with the final concentrations very close to those observed in model wine. When treated with either grape or wine tannin extracts in model wine, the concentration of 4 was found to decrease to levels very close to those observed with an untreated red wine. When white wine was heated at 45 degrees C, 4 was formed, indicating the presence of precursor forms. The amounts formed were much higher than those found in a commercial white wine. 4 was also observed in red wine heated to 45 degrees C, but the concentration produced was much less than that with white wine.  相似文献   
113.
It was previously found that the bioavailability of Se from Se-rich spirulina (SeSp) was lower than that from selenite or selenomethionine when fed to Se-deficient rats. The present study examined the bioavailability of Se from SeSp subfractions: a pellet (P) issuing from the centrifugation of a suspension of broken SeSp and a retentate (R) resulting from ultrafiltration of the supernatant through a 30 kDa exclusion membrane. Animals were fed a torula yeast based diet with no Se (deficients) or supplemented with 75 microg of Se/kg of diet as sodium selenite (controls) for 42 days. Se-deficient rats were then repleted for 56 days with Se (75 microg/kg of diet) supplied as sodium selenite, SeSp, P, or R. During this period, controls continued to receive sodium selenite. Speciation of Se in subfractions showed that the majority was present in the form of high molecular weight compounds; free selenomethionine was only a minor constituent. Gross absorption of Se from sodium selenite, P, and R was not different and was higher than from SeSp. Only retentate allowed full replenishment of Se concentration in liver and kidney (as did sodium selenite) and glutathione peroxidase (GSHPx) activity in liver, kidney, plasma, and erythrocytes. The bioavailabilities of Se in retentate, as assessed by slope ratio analysis using selenite as a reference Se, were 89 and 112% in the tissue Se content and 106-133% in the GSHPx activities. SeSp and P exhibited a gross bioavailability of <100%. These results indicate that Se in retentate is highly bioavailable and represents an interesting source of Se for food supplementation.  相似文献   
114.
The objectives of this investigation in the HolyCross Mountain region of Poland were (1) to determineconcentration ranges and (2) mobility of elements within fivedetailed soil profiles and their apparent impact on thechemistry of some plant bioindicators, i.e. lichen thalli ofthe species Hypogymnia physodes (L.) Nyl. and Scotspine (Pinus sylvestris L.) bark. The results ofelemental determinations performed on soils and vegetationfrom the Holy Cross Mts show that some concentrations ofelements are elevated primarily due to air pollution.However, since 1994 a steady decrease in the content of S andsome heavy metals has been recorded in all the mediaexamined. Concentrations of many elements in H.physodes thalli and P. sylvestris needles of the Holy Cross Mountains are generally similarto those in other areas of Europe.  相似文献   
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Transforming growth factor (TGF) β and its receptors are expressed at the conceptus-maternal interface during early pregnancy in the pig. The present studies were conducted to examine: (1) the effect of conceptus products on TGFβ1 mRNA expression and protein concentration in the porcine endometrium using in vivo and in vitro models, and (2) the effect of TGFβ1 on proliferation of porcine trophoblast cells in vitro. During in vivo experiments, gilts with one surgically detached uterine horn were slaughtered on days 11 or 14 of the estrous cycle and pregnancy. For in vitro studies, endometrial explants and luminal epithelial (LE) cells co-cultured with stromal (ST) cells were treated with conceptus-exposed medium (CEM). Moreover, porcine trophoblast cells were treated with TGFβ1, and the number of viable cells was measured. On day 11, the presence of conceptuses had no effect on TGFβ1 mRNA expression, but decreased the TGFβ1 protein concentration in the connected uterine horn compared with the detached uterine horn. In contrast to day 11, on day 14 after estrus, TGFβ1 mRNA expression and protein content in the endometrium collected from the gravid uterine horn were greater when compared with the contralateral uterine horn. The treatment of endometrial slices with CEM resulted in greater TGFβ1 mRNA expression and protein secretion. LE cells responded to CEM with an increased TGFβ1 mRNA level. Moreover, TGFβ1 stimulated the proliferation of day 14 trophoblast cells. In summary, porcine conceptuses may regulate TGFβ1 synthesis in the endometrium at the time of implantation. TGFβ1, in turn, may promote conceptus development by increasing the proliferation of trophoblast cells.  相似文献   
118.
The study aimed at defining reference values for electrocardiographic (ECG) and echocardiographic parameters as well as macroscopic dimensions of the heart and microscopic dimensions of cardiomyocytes in the European brown hare. The studies were conducted on 30 adult, clinically healthy hares of either sex caught in Poland. ECG and echocardiography were performed supravitally on anaesthetized hares. After euthanasia, gross and microscopic myocardial and cardiomyocyte dimensions were determined. Heart rate amounted to 140 ± 37.5 beats/min, the leading rhythm involved the sinus rhythm. P wave time was 26 ± 5 ms, PQ time was 80 ms, QRS time was 29 ± 3.5 ms, and ST was 97.5 ± 7 ms. Echocardiography determined a left ventricular wall end-diastolic diameter of 8.6 ± 2.0 mm and an intraventricular septum end-diastolic diameter of 5.75 ± 1.0 mm. The thickness of the interventricular septum corresponded to that of the free wall of the left ventricle, a finding consistent with physiological hypertrophy. Preliminary reference values were established for echocardiography. The findings were similar to those obtained at necropsy. The ECG and echocardiographic studies represent the first supravital examination of cardiac function in the hare. The obtained results illustrate adaptation of hare''s myocardium to its mode of life. The cardiac findings resemble the athlete''s heart syndrome described in humans. The findings may prove useful in further studies on the physiology of the cardio-vascular system in the hare.  相似文献   
119.
This study was designed to determine the effect of feeding female rats with low-calcium diet containing one of three fructan sources (Jerusalem artichoke, yacon, Beneo Orafti Synergy1), on selected bone parameters. Growing Wistar rats were fed modified AIN-93 G diet enriched in fructan sources (8%), added alone or as a strawberry sorbet ingredient. Two of eight groups were a validation model, where the positive control group was fed with recommended calcium dose in the diet (RCD), and negative one – with low calcium diet (LCD). After 12 weeks, femoral Ca content, bone densitometry, architecture and hardness were examined. The positive effects on femoral Ca content and cortical thickness, area and content in distal part of bone was observed after feeding animals diet enriched in Jerusalem artichoke sorbet. Beneficial action on other bone tomographic parameters (particularly trabecular volumetric bone mineral density) in this part of femur were associated mainly with the consumption of the diet with sorbet containing yacon. Our results showed an important role of diet containing frozen strawberry desserts enriched in fructan sources in the maintenance of healthy bones of growing organism. It may suggest possible synergisms between fructans and bioactive substances of strawberry.  相似文献   
120.
Methyl orange (MO), methylene blue (MB), phenol (F), salicylic acid (SA), and rhodamine B (ROD) were used as substrates during the photodegradation experiments in the absence and in the presence of nanostructured Ag/titania-silica. The catalyst was characterized by scanning electron microscopy (SEM), scanning transmission electron microscope high-angle annular dark field (STEM-HAADF), stereological analysis, nitrogen adsorption-desorption, and X-ray photoelectron spectroscopy (XPS) measurements. The results were fitted on pseudo-first and pseudo-second kinetic order models. The film diffusion was also determined. The photolysis degrades MO and F to a greater extent than the photocatalysis. The degradation of SA occurred at the same rate either by photolysis or by photocatalysis. MB was best removed by photocatalysis. With regard to the photocatalysis, the highest rates of film diffusion were obtained for MB, F, and ROD, meaning that these molecules crossed the film to arrive at the catalyst surface more rapidly than the others. For MO and MB, the results followed the pseudo-first-order kinetic model while for SA, F, and ROD, the pseudo-second-order kinetic model was more appropriate.  相似文献   
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