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1.
The primary objective of this experiment was to determine the effects of heat treatment on the standardized ileal digestibility(SID) of amino acids(AA) in corn distillers dried grains with solubles(DDGS) fed to growing pigs. The second objective was to develop regression equations that may be used to predict the concentration of SID AA in corn DDGS. A source of corn DDGS was divided into 4 batches that were either not autoclaved or autoclaved at130°C for 10, 20, or 30 min. Four diets containing DDGS from each of the 4 batches were formulated with DDGS being the only source of AA and CP in the diets. A N-free diet also was formulated and used to determine the basal endogenous losses of CP and AA. Ten growing pigs(initial BW: 53.5 ± 3.9 kg) were surgically equipped with a T-cannula in the distal ileum and allotted to a replicated 5 × 4 Youden square design with 5 diets and 4 periods in each square. The SID of CP decreased linearly(P 0.05) from 77.9% in non-autoclaved DDGS to 72.1, 66.1, and 68.5% in the DDGS samples that were autoclaved for 10, 20, or 30 min, respectively. The SID of lysine was quadratically reduced(P 0.05) from 66.8% in the non-autoclaved DDGS to 54.9, 55.3, and 51.9% in the DDGS autoclaved for 10, 20, or30 min, respectively. The concentrations of SID Arginine, Histidine, Leucine, Lysine, Methionine, Phenylalanine, or Threonine may be best predicted by equations that include the concentration of acid detergent insoluble N in the model(r2= 0.76, 0.68, 0.67, 0.84, 0.76, 0.73, or 0.54, respectively). The concentrations of SID Isoleucine and Valine were predicted(r2= 0.58 and 0.54, respectively) by the Lysine:CP ratio, whereas the concentration of SID Tryptophan was predicted(r2= 0.70) by the analyzed concentration of Tryptophan in DDGS. In conclusion, the SID of AA is decreased as a result of heat damage and the concentration of SID AA in heat-damaged DDGS may be predicted by regression equations developed in this experiment.  相似文献   
2.
The antioxidant capacity of low molecular weight phenols found in olive fruit and in virgin olive oil has been investigated. The radical scavenging activity of some of the investigated phenols is higher than that of the most used antioxidants, and among them, 3,4- or 2,5-dihydroxyl phenols are also able to chelate copper ions leading to chelates that are only slightly active in the promotion of free radical reactions. The ability of tested phenols to reduce Cu(II) and their activity-structure relationships was also studied, showing that their reducing capacity is connected to the presence of a specific ligand of the reduced ion. The number of reduced ions per mole of phenol is lower than that calculated for some flavonols and isoflavones so exerting a lower prooxidant action. This fact may be important in vivo when free transition metal ions are involved in oxidation processes.  相似文献   
3.
Changes in the concentration of tocopherol, monophenols, o-diphenols, squalene, and polyunsaturated fatty acids in olive oil were evaluated during 1 year at various storage conditions. Samples of two different extra virgin olive oil (EOO), produced in Calabria (Italy), were stored in dark and in colorless bottles, filled up completely or to half, in order to simulate the domestic storage conditions. The extent of oxidation or photooxidation was monitored by periodic measurements of peroxide values and the rate of degradation of alpha-tocopherol, o-diphenols, squalene, and polyunsaturated fatty acids. The quantitative analysis of the constituents has been performed by HPLC-DAD, HPLC-MS, and GC-MS. The main changes in the concentrations of the analyzed compounds were associated with the major oxygen level in the half-empty glass bottles. alpha-Tocopherol was the first molecule to be oxidized (-20% after 2 months, -92% after 12 months). Squalene and o-diphenols were protected in the first months by the presence of alpha-tocopherol, and their content decreased significantly only after 6 and 8 months, respectively, in the half-empty bottles. The concentration of polyunsaturated fatty acids remained almost constant during 8 months for all four different storage conditions; their oxidation started when the level of the antioxidants decreased.  相似文献   
4.
In 2 experiments, 48 weanling (initial BW: 13.5 ± 2.4 kg, Exp. 1) and 24 growing pigs (initial BW: 36.2 ± 4.0 kg, Exp. 2) were used to determine effects of a novel bacterial 6-phytase expressed in Aspergillus oryzae on the apparent total tract digestibility (ATTD) of phosphorus and calcium in corn-soybean meal diets fed to weanling and growing pigs. In Exp. 1 and 2, pigs were randomly allotted to 6 dietary treatments using a randomized complete block design and a balanced 2 period changeover design, respectively. In both experiments, 6 diets were formulated. The positive control diet was a corn-soybean meal diet with added inorganic phosphorus (Exp. 1: 0.42 and 0.86% standardized total tract digestible phosphorus and total calcium, respectively; Exp. 2: 0.32 and 0.79% standardized total tract digestible phosphorus and total calcium, respectively). A negative control diet and 4 diets with the novel phytase (Ronozyme HiPhos, DSM Nutritional Products Inc., Parsippany, NJ) added to the negative control diet at levels of 500, 1,000, 2,000, and 4,000 phytase units (FYT)/kg were also formulated. In Exp. 1, the ATTD of phosphorus was greater (P < 0.01) for the positive control diet (60.5%) than for the negative control diet (40.5%), but increased (linear and quadratic, P < 0.01) as phytase was added to the negative control diet (40.5% vs. 61.6%, 65.1%, 68.7%, and 68.0%). The breakpoint for the ATTD of phosphorus (68.4%) was reached at a phytase inclusion level of 1,016 FYT/kg. In Exp. 2, the ATTD of phosphorus was greater (P < 0.01) for the positive control diet (59.4%) than for the negative control diet (39.8%) and increased (linear and quadratic, P < 0.01) as phytase was added to the negative control diet (39.8% vs. 58.1%, 65.4%, 69.1%, and 72.8%). The breakpoint for the ATTD of phosphorus (69.1%) was reached at a phytase inclusion level of 801 FYT/kg. In conclusion, the novel bacterial 6-phytase improved the ATTD of phosphorus and calcium in both weanling and growing pigs. The optimum level of inclusion for this phytase is 800 to 1,000 FYT/kg of complete feed to maximize ATTD of phosphorus and calcium in weanling and growing pigs.  相似文献   
5.
Contrast-enhanced ultrasound was used to study focal and multifocal lesions of the spleen in 26 dogs and two cats affected by 11 benign and 18 malignant splenic diseases. A second-generation microbubble contrast medium (Sonovue) was injected into the cephalic vein and enhancement patterns were subjectively described and time intensity curves calculated. Final diagnosis was obtained by histopathologic examination after splenectomy (n=19) or by needle aspiration and sonographic follow-up after 4 and 8 weeks (n=9). Contrast-enhanced ultrasound parameters, improving the characterization between benign and malignant lesions, were established. The most useful criterion was the hypoechogenicity of the lesion in the wash-out phase combined with the presence of tortuous feeding vessels, which was observed in association with malignancy. All malignant lesions were hypoechoic to the surrounding spleen 30s after starting the contrast medium injection. Lymphosarcoma and hemangiosarcoma had characteristic perfusion patterns. Lymphosarcoma had rapid time to peak and early wash-out phase with a honeycomb pattern during the wash-out. Hemangiosarcomas were large nonperfused masses in all phases surrounded by hypervascular splenic parenchyma. Benign lesions except one hematoma and a benign histiocytoma had the same perfusion pattern as the surrounding spleen. Ultrasonographic and contrast-enhanced ultrasound findings of an accessory spleen are reported. Contrast-enhanced ultrasound can improve the characterization of focal or multifocal lesions of the spleen.  相似文献   
6.
Brassica oleracea L. is an important species that originated in the eastern Mediterranean area. From there, B. oleracea L. subsp. capitata (L.) DC. convar. botrytis (L.) Alef. var. italica Plenck (broccoli) was introduced into Italy where considerable diversification took place. Several landraces of broccoli, which are highly appreciated by local people for their organoleptic traits, are presently cultivated in both large fields and home gardens. In this study, 10 landraces, 4 synthetics derived from landraces and 4 of the most used F1 hybrids were characterised for morpho-physiological and molecular traits with the principal aim of feeding information into the landrace protection schemes being developed in Italy and into breeding programs. The landraces and derived synthetics are well differentiated from each other and from the F1 hybrids for important agronomic and genetic traits. The principal component analysis based on analysis of morpho-physiological traits showed that overall the 2 main components accounted for 67.74 % of the total variation. The neighbour joining tree, based on 23 microsatellite markers, grouped accessions into 2 main clusters. One includes one synthetic variety and 2 F1 hybrids, while the other cluster includes all the other accessions. There were also several sub clusters. Most of the materials examined showed within-accession diversity. The information gathered in this study can be used to protect landraces through the schemes presently being developed in Italy and to register them in the European common catalogue of “conservation varieties”. In situ (on-farm) conservation of landrace diversity is discussed with reference to landrace use.  相似文献   
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9.
The luminal surface of the gastrointestinal tract is covered by a mucus gel layer that acts to protect gut epithelial cells from the harsh luminal environment. This study investigated the use of two human colonic adenocarcinoma cell lines, HT29-MTX-E12 and HT29, as a model to mimic gut epithelium with and without a mucus gel layer. The effect of adding the tea polyphenols epigallocatechin gallate (EGCG) and epicatechin (EC) to the cells with subsequent examination of cell morphology and viability was assessed. EGCG, at the concentrations tested, was very toxic to the HT29 cells, but less toxic to the HT29-MTX-E12 cells, suggesting that the mucus gel layer on the HT29-MTX-E12 cells can protect the cells against EGCG toxicity. In contrast, EC had no effect on the viability of either the HT29 or HT29-MTX-E12 cells, suggesting that proteins within the mucus gel layer on the apical surface of gut epithelial cells may bind to the galloyl ring of EGCG. The effect of adding food-related ingredients with the ability to complex with EGCG, β-casein and maltodextrin, on cell viability was also examined. The presence of β-casein was very effective in protecting the cells against the toxicity effect of EGCG, but maltodextrin, at the concentration tested, was less effective in protecting against this toxicity. In conclusion, the results demonstrate that the mucus gel layer on HT29 human colonic adenocarcinoma cells may protect these cells against EGCG toxicity. In addition, the data showing reduced toxicity of EC compared to that of EGCG suggest that the cytotoxic effects of high polyphenol levels may be associated with the ability of polyphenols to interact with cellular proteins and mucins.  相似文献   
10.
The enzymatic activity of the soil and potential plant growth can both be affected by the addition of different substances, such as biostimulants. The final objective of this work was to evaluate the effect of Chlorella vulgaris, Scenedesmus quadricauda or their extracts applied directly into the soil, by monitoring the complex soil-microorganism-plant system. Experiments were conducted in pots using agricultural soil and tomato plants in a growth chamber at 25 ± 2 °C illuminated by artificial light with a 16-h photoperiod. The soil biological activity was analyzed by monitoring fluorescein diacetate hydrolysis, dehydrogenases, acid and alkaline phosphomonoesterase and urease activities. Dry weight and chlorophyll index values of tomato plants were also investigated. Results showed that both the microalgae and their extracts positively affected soil biological activity by increasing values of the biochemical index of potential soil fertility (Mw) both in cultivated and uncultivated soils. The highest Mw value was reached in cultivated soil treated for 11 days with the lower concentration of S. quadricauda extract (Mw 9.47). All treatments significantly increased the growth of tomato plants with respect to untreated soil. These results are very promising with a view to improving soil biological activity as well as increasing plant growth.  相似文献   
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