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91.
In the present study, the effect of nitrogen, applied as a controlled atmosphere treatment on the microbial and entomological loads, as well as on the organoleptic characteristics of stored dried currants (Corinthian raisins, Vitis vinifera L. var. Apyrena), was investigated. Trials were conducted under “real world” conditions, in the nitrogen chambers of a commercial facility, in which nitrogen was introduced by using an incorporated nitrogen generator. Prior to the initiation of the trial, chambers were filled with pallets carrying dried black currants. Subsequently, currants were artificially infected with all life stages of Tribolium confusum, eggs and larvae of Ephestia elutella and adults of Oryzaephilus surinamensis. Currants were exposed for 3 days in nitrogen (O2 concentration <1 %) at two temperature levels, 25 and 38–43 °C. After treatment, insect mortality was recorded and currant samples were collected and forwarded for microbial analysis and determination of their organoleptic characteristics. When nitrogen was applied at 25 °C, high insect mortality levels were noted; however, in most cases there were a number of insects that survived the nitrogen treatment. In contrast, complete control was achieved at 38–43 °C for all insect species and life stages tested, with the exception of T. confusum larvae. Nitrogen application at 25 °C had no effect on total microbial and yeast and mould counts, while both were reduced at 38–43 °C. Sensory attributes of Corinthian currants remained acceptable after nitrogen fumigation, although taste, odour, aroma and overall acceptance were affected by the treatments. Total phenolic as well as 5-hydroxymethylfurfural content increased after nitrogen application at 38–43 °C, while the lower temperature applied had no effect. The results of the present study suggest that nitrogen-based controlled atmosphere at elevated temperature could be a valuable tool for ensuring clean, pest-free, hygienic standards in dried Corinthian currants.  相似文献   
92.
Resveratrol is a natural polyphenol and possesses many biological functions such as anti-inflammatory activity and protection against atherosclerosis and myocardial infraction. Parkinson's disease is a common progressive neurodegenerative disease. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is the most useful neurotoxin to induce Parkinsonism. The present study was carried out to elucidate the neuroprotective effect and possible mechanism of resveratrol on MPTP-induced striatal neuron loss. Sixty adult Balb/c mice were divided into four groups: sham operation, MPTP treatment (30 mg/kg, i.p.), MPTP combined with resveratrol administration (20 mg/kg, i.v.), and resveratrol treatment alone. Microdialysis and high-performance liquid chromatography were used to analyze dihydroxybenzoic acid (DHBA) that reflected the hydroxyl radical level. In the present study, we found MPTP chronic administration significantly induced motor coordination impairment in mice. After MPTP administration, the hydroxyl radical levels in substantia nigra were also significantly elevated and animals displayed severe neuronal loss. Resveratrol administration significantly protected mice from MPTP-induced motor coordination impairment, hydroxyl radical overloading, and neuronal loss. Our results demonstrated that resveratrol could elicit neuroprotective effects on MPTP-induced Parkinsonism through free radical scavenging.  相似文献   
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1. The aim of this study was to examine the effects of roxarsone (3-nitro-4-hydroxyphenylarsonic acid) inclusion in the diet on the performance, liver function and lipid metabolism in the liver of laying Brown Tsaiya ducks. 2. Sixty 36-week-old laying ducks were selected and allocated at random into 4 dietary treatments with 3 replications for each treatment. Feeding was for 7 weeks with 3 weeks of experimental diets followed by a 4 week withdrawal period. The experimental diets were supplemented with 0, 50, 100 and 300 mg/kg roxarsone, respectively 3. Dietary inclusion of 50 or 100 mg/kg roxarsone did not significantly promote performance. Inclusion of 300 mg/kg significantly depressed (P<0.05) performance, liver weight and content, serum triacylglycerol (TG), serum nonesterified fatty acid (NEFA) and increased (P<0.05) cholesterol, creatine kinase (CK) and aspartate aminotransferase (AST) in the serum at the end of 3 weeks on the experimental diet. 4. Laying characteristics returned to normal 4 weeks after withdrawal of roxarsone. The liver weight, fat and TG in the liver and serum concentrations of TG, NEFA, high density lipoprotein (HDL) and AST increased significantly (P<0.05), while the level of very low density lipoprotein (VLDL) decreased (P<0.05) at the end of the withdrawal period. More prominent vacuolised hepatic fatty cells were observed in laying ducks treated with 300 mg/kg of roxarsone.  相似文献   
96.
The aim of this study was to evaluate the immune responses in hybrid tilapia (Nile tilapia Oreochromis niloticus x Mozambique tilapia O. mossambicus) and Japanese eels Anguilla japonica after treatment with five glycans: barley, krestin, MacroGard, scleroglucan, and zymosan. The effects of the glycans on the innate immune responses of the fish were investigated using the phagocytic index (PI), lysozyme activity, complement opsonization, and activation assay. The results of the lysozyme assay demonstrated that the lysozyme activities increased after treatment with glycans. Moreover, based on the PI, treatment with each of the five glycans resulted in increased phagocytic activities in anterior kidney and peripheral blood phagocytes in both tilapia and Japanese eels. The opsonic effect of complement on phagocytosis in tilapia and Japanese eels were investigated using baker's yeast, which served as the activator in the classical complement pathway (CCP) and in the alternative complement pathway (ACP). Tilapia and Japanese eel sera that were treated with glycans greatly enhanced phagocytosis. The classical pathway--hemolytic complement titer (CH50) of Japanese eels treated with glycans was slightly increased in vitro and in vivo. While glycan treatment enhanced the CCP of both species in vitro and in vivo, the alternative pathway-hemolytic complement titer (ACH50) was only increased in vitro and in vivo in glycan-treated tilapia. Thus, it follows that the ACP must have been activated in tilapia treated with glycans. However, in Japanese eels, the ACH50 of the ACP activation assay was undetected in vitro or in vivo due to possible unknown factors in the Japanese eel serum that caused lysis of the rabbit red blood cells. Our study investigated the effects of glycans used to enhance phagocytosis and activate both of the complement pathways involved in stimulating the innate immune responses of Japanese eels and tilapia.  相似文献   
97.
Wheat starch samples containing Cloisite Na+ and 30B nanoclays were extruded from a twin‐screw extruder. Moisture content, temperature, and screw speed were varied to determine their effect on nanoclay dispersion. X‐ray diffraction and transmission electron microscopy (TEM) were used to examine nanoclay intercalation and exfoliation. Moisture content had the largest effect on Cloisite Na+ dispersion, with the highest moisture sample containing exfoliated nanoclays. Meanwhile, temperature and screw speed had little effect on Cloisite Na+ dispersion. For Cloisite 30B samples, only an increase in temperature produced slight intercalation of nanoclays. This was due to the incompatibility of starch with the more hydrophobic Cloisite 30B. Also, Cloisite Na+ and 30B intercalation did not depend on specific mechanical energy. In addition, water absorbance tests indicated the Cloisite Na+ sample containing the most well‐dispersed nanoclays had the lowest water uptake.  相似文献   
98.
Spring (February to June) and fall (August to December) crops of soybean grown yearly in Taiwan with reverse temperature patterns provide a novel model to assess the effect of the crop season. In this study, three soybean cultivars, namely CH 1, VS-KS 2, and HBS, were grown for 2001 fall, 2002 spring, 2003 fall, 2004 spring, 2004 fall, and 2005 spring crops. The harvested and sun-dried soybeans were lyophilized, pulverized, and stored at -25 degrees C until HPLC analyses of isoflavone compositions were performed. As affected by extraction solvent and HPLC mobile phase, the amount of isoflavones extracted by methanol-H(2)O was higher than those extracted by acetic acid-acetonitrile. In addition, when both extracts were subjected to HPLC analysis with reversed C18 column run respectively with methanol-H(2)O and acetic acid-acetonitrile mobile phases, malonyldaidzin, malonylglycitin, and malonylgenistin were not detected in the former phase. Accordingly, all harvested soybeans were subjected to methanol-H(2)O extraction and HPLC analysis with the acetic acid-acetonitrile mobile phase. Among the detected soybeans, daidzin, genistin, malonyldaidzin, and malonylgenistin were the majors and glycitin, malonylglycitin, daidzein, and genistein were the minors of isoflavones. As affected by crop season for each cultivar grown for 3 years, daidzin, genistin, malonyldaidzin, and malonylgenistin contents of soybeans of the fall crops were significantly higher than those of their spring crops ( p < 0.05).  相似文献   
99.
The objective of this study was to express major epitopes of heterogeneous nuclear ribonucleoprotein G (hnRNP G) for detecting anti-hnRNP G antibodies in dogs with systemic lupus erythematosus (SLE). HnRNP G cDNA clone was isolated from HEp-2 cells, and a DNA fragment encoding immunodominant region (residues 189-272) of hnRNP G (hnRNP Gi) was subcloned into pET32 vector to construct a prokaryotic expression plasmid named pEThnRNPGi. After induction, Escherichia coli carrying pEThnRNPGi expressed a recombinant protein of 28 kDa, comprising recombinant hnRNP Gi and fusion tag. Purified recombinant hnRNP Gi protein was further analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and its identity was confirmed. Western blot analysis showed that recombinant hnRNP Gi was specifically recognized by anti-hnRNP G positive sera of SLE dogs, and not by negative control sera. In conclusion, recombinant hnRNP Gi protein expressed in this study may serve as a useful reagent to assist in the immunological diagnosis of canine SLE.  相似文献   
100.
Squalene was identified by gas chromatography-mass spectrometry and high-performance liquid chromatography (HPLC) spiking analyses in the supercritical CO(2) extracts of freeze-dried abscisic leaves of Terminalia catappa L. When the freeze-dried abscisic, senescent, mature, and immature leaves and seeds were subjected to supercritical CO(2) extraction at 40 degrees C and 3000 psi and HPLC quantitation, squalene contents were 12.29, 2.42, 1.75, 0.9, and 0% in the extracts and corresponding to 1499, 451, 210, 65, and 0 microg/g in the freeze-dried sample, respectively. When the extracts were applied for antioxidative characterization by supplementation in an iron/ascorbate system with linoleic acid and in a pork fat storage system for inhibition of conjugated diene hydroperoxide (CDHP) formation or in a free radical scavenging system with 1,1-diphenyl-2-picryl-hydrazyl (DPPH), the extracts of leaves exhibited potent antioxidative and DPPH scavenging activities and increased with an increase of leaf maturity. However, the seed extracts only exhibited potent inhibition of CDHP formation and very low DPPH scavenging activity.  相似文献   
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