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21.
The Hass cultivar of avocado is the most widely grown commercial cultivar in Mexico. Unfortunately, this cultivar is poorly adapted to the Mexican low-lands with hot dry climates characteristic of northwestern Mexico. Other well-adapted avocado accessions are available for these regions, but their nutritional traits and genetic diversity have yet to be explored. In this study, we analyze oil content, (α-tocopherol) and genetic variation among five local varieties from northwest Mexico that grow in high temperatures regimes in unfertilized soils and without any agronomic management. We report significant phenotypic variability in oil and α-tocopherol components in different accessions of avocado as determined by HPLC. Interestingly, we find higher α-tocopherol content (45.02–50.66 μg/g of fresh pulp) in some local avocados compared to Hass (32.28 μg/g of fresh pulp). The analyzed accessions represent a moderately polymorphic set of genotypes as measured by microsatellite (10 alleles by locus) and SNP (1 SNP every 164.4 bp) analysis of the VTE3 and VTE4 genes, implied in the biosynthesis of tocopherols. SNP data allowed also identifying differences between the local varieties and controls (Hass and the Mexican race accession). The variation observed at the genetic, morphologic and nutritional levels provide significant new information that may be valuable in selecting and developing avocado genotypes adapted to high-temperature environments.  相似文献   
22.
The aim of this study was to investigate whether etamsylate produces equine platelet activation. In vitro and in vivo studies were designed in which seven and eight adult healthy horses were included, respectively. In the in vitro study, citrated blood was incubated with different concentrations of etamsylate, and P-selectin expression and annexin V binding were determined by flow cytometry. In the in vivo study, blood was collected before and 1 and 2h after IV administration of etamsylate, and P-selectin expression was evaluated. In the in vitro study, a significant increase in P-selectin expression, leukocyte-platelet aggregate formation and annexin V binding were observed. In the in vivo study, a marked increase in P-selectin expression and heterotypic aggregate formation was seen in two and five horses, respectively, although no significant differences were detected when analyzing results from all the animals together. The results of the in vitro study indicate that etamsylate produces a pre-activation state in equine platelets, but this fact could be confirmed by the in vivo study.  相似文献   
23.
Commercial abalone culture is carried out using flow‐through systems with a high water volume exchange in Baja California, Mexico. The objective of this work was to compare the growth rate and survival of red abalone cultured in two systems. Flow through (daily water exchange rate of 800%) and recirculating systems consisted of a 250 L fibreglass tank and constant aeration, but biofiltration in the recirculating system was provided with a 28 L (1 ft3) bubble‐washed bead filter. Water variables were measured either daily (dissolved oxygen, temperature, pH and salinity) or three times a week (total ammonia nitrogen, nitrate‐nitrogen, nitrite‐nitrogen and alkalinity). Shell length was measured every 2 weeks for 18 weeks. Only the alkalinity and pH were significantly different due to the addition of sodium bicarbonate to the recirculating system. Abalone growth rate was 26.1 ± 15.96 μm day?1 in the recirculating systems and 22.21 ± 18.69 μm day–1 in the flow‐through systems. The final survival was 78.74% in the recirculating systems and 71.82% in the flow‐through systems. Significant differences in the final size and survival of the abalones were found between systems (P<0.05). Therefore, recirculating aquaculture systems is a feasible alternative for juvenile red abalone culture.  相似文献   
24.
The characteristic of proteins, starch and pectic substances in cotyledons of two bean cultivars varying in cooking time were determined to investigate their possible contribution to bean cooking quality. Both cultivars showed the same enthalpies of starch gelatinization but different protein denaturation enthalpies. The proportion of hot water soluble pectins was higher in Michigan, the cultivar with the lower cooking time, than in Ojo de Cabra, the cultivar with the higher cooking time. These results were not due to differences in pectin methylation or in the ratio of monovalent to divalent cations in the tissue, suggesting that in fresh beans the β-elimination reaction is not the sole or predominant route of thermal pectin degradation. Overall, this study indicates that varietal differences in bean cooking quality may be reflections of the rate of pectin loss during soaking/heating and that the thermal properties of starch and protein fractions seem to have a minor contribution. Researchers involved in this study propose that in fresh beans, the thermal pectin loss results from a two step mechanism: pectin enzymic breakdown during the bean soaking followed by thermal solubilization rather than β-elimination during the bean heating.  相似文献   
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26.
Muscle fluid was investigated as an alternative to serum for detecting anti-hepatitis E virus (HEV) antibodies in slaughter pigs. Samples of serum and diaphragmatic muscle juice from 67 pigs were analysed by anti-HEV IgG ELISA. Compared to the serum ELISA, the ELISA on diaphragmatic muscle fluid had a sensitivity of 93%, a specificity of 91.7%, a κ value of 0.84 and a determination coefficient (R(2)) of 0.77; both tests had global agreement of results. Muscle fluid can be used as an alternative to serum for serological detection of HEV antibodies in slaughter pigs.  相似文献   
27.
Plant Foods for Human Nutrition - Technologies such as UV-A radiation applied to sprouted sorghum can stimulate the synthesis or release of phenolic compounds. Since the optimal conditions for...  相似文献   
28.
The purpose of the present study was to explore the most likely natural route of infection of swine hepatitis E virus (HEV) by oral inoculation of pigs and to investigate the potential infection by direct contact exposure. A preliminary experiment was performed to assess the infectiousness of the bile used as source of virus. Once confirmed, 16 pigs were inoculated via oral drop with an HEV positive bile suspension containing 2 × 105 genome equivalents per pig. Nine animals were kept as contact sentinels and 12 more pigs were used as negative controls. A number of pigs from the three groups were euthanized at 16, 32 and 64 days post-inoculation. From the HEV inoculated group, three pigs shed virus in faeces, two had virus RNA in bile at necropsy and two seroconverted. In the contact group, two animals showed presence of HEV RNA in bile. This study demonstrates that pigs orally inoculated with a single HEV dose got infection, although few animals had evidence of infection. Moreover, the virus was successfully transmitted to direct contact exposed pigs.  相似文献   
29.
Chiltepin, a wild chili mostly used in different traditional foods and traditional medicine in Northwest Mexico, represents a source of polyphenols. However, studies about the bioaccessibility of polyphenols as a parameter to measure the nutritional quality and bioefficacy of them in the fruit after consumption are scarce. Chiltepin showed phenolic acids and flavonoids contents between 387 and 65 μg/g, respectively. Nevertheless, these values decreased after the digestion process. Before digestion, gallic acid, 4-hydroxibenzoinc acid, chlorogenic acid, caffeic acid, p-coumaric acid, quercetin and luteolin were the main polyphenols found in chiltepin by HPLC-DAD and confirmed by FIA-ESI-IT-MS/MS. Gallic and chlorogenic acids were non-detected in the gastric phase, while only p-coumaric acid (5.35?±?3.89 μg/g), quercetin (5.91?±?0.92 μg/g) and luteolin (2.86?±?0.62 μg/g) were found in the intestinal phase. The bioaccessibility of phenolic acids, flavonoids, and total polyphenols after the intestinal phase was around 24, 17 and 23%, respectively. Overall, results indicated that release of polyphenols from chiltepin fruit might be affected by the food matrix and gastrointestinal conditions due to the low bioaccessibility values observed.  相似文献   
30.
An organic extract from fresh shrimp (Litopenaeus vannamei) was studied for antimutagenic and antiproliferative properties using Salmonella typhimurium tester strains TA98 and TA100 with metabolic activation (S9) and a cancer cell line (B-cell lymphoma), respectively. Shrimp extract was sequentially fractionated by thin layer chromatography (TLC) and each fraction was tested for antimutagenic and antiproliferative activities. Crude organic extracts obtained from shrimp reduced the number of revertants caused by aflatoxina B(1), showing a dose-response type of relationship. Sequential TLC fractionation of the active extracts produced several antimutagenic and/or antiproliferative fractions. These results suggested that the lipid fraction of the tested species contained compounds with chemoprotective properties that reduce the mutagenicity of AFB(1) and proliferation of a cancer cell line.  相似文献   
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