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In vitro and in vivo studies of the health and nutritional properties of durian (Durio zibethinus Murr.) were compared with snake fruit (Salacca edulis Reinw.) and mangosteen (Garcinia mangostana). Dietary fibers, minerals, and trace metals were comparable. Total polyphenols (mg of GAE/100 g of FW) and flavonoids (85.1+/-6.1) were significantly higher (p<0.05) than in snake fruit (217.1+/-13.2 (mg of CE/100 g of FW)), durian (309.7+/-19.3 and 61.2+/-4.9), and mangosteen (190.3+/-12.1 and 54.1+/-3.8). Antioxidant activity (microM TE/100 g of FW) of durian measured by DPPH and ABTS assays (228.2+/-13.4 and 2016.3+/-81.1) was significantly higher (p<0.05) than in snake fruit (110.4+/-7.9 and 1507.5+/-70.1) and mangosteen (79.1+/-5.9 and 1268.6+/-62.3). HPLC/DAD analysis of durian (microg/100 g of FW) showed that quercetin (1214.23+/-116.7) was present at levels three times that of caffeic acid, and twice as high as p-coumaric and cinnamic acids. The correlation coefficients between the bioactive compounds of fruits and their antioxidant activities were high (R2=0.99). Male Wistar rats (25) were divided into five dietary groups: the control group was fed the basal diet (BD); in addition to BD, the cholesterol (Chol) group was supplemented with 1% of Chol; the diets of the Chol/Durian, Chol/Snake, and Chol/Mangosteen groups were supplemanted with 5% of these fruits, respectively. It was found that diets supplemented with durian, and to a lesser degree with snake fruit and mangosteen, significantly hindered the rise in plasma lipids and the decrease in antioxidant activity. The nutritional values were comparably high. In conclusion, it could be suggested that inclusion of studied tropical fruits, especially durian, in known disease-preventing diets could be beneficial.  相似文献   
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The effect of four sterol biosynthesis-inhibiting fungicides added to the pitching wort on the evolution of several organoleptic parameters during the primary fermentation of young lager beer was assessed. Pyrimidine (nuarimol and fenarimol) and triazole (myclobutanil and propiconazole) fungicides were individually supplied to the pitching wort to obtain a concentration of 1 mg/L. A marked influence in the fermentation rate was observed for the samples with propiconazole residues. From the fourth day onward, the fermentation prematurely ceased (stuck fermentation), and therefore, statistical significant differences were found in fermented extract, alcohol content, fermentable carbohydrates, pH, color, and total polyphenol and flavonoid contents of beer. Myclobutanil residues are only influenced in the total polyphenol and flavonoid contents, while differences in the analyzed parameters were not noticeable for the samples containing nuarimol and fenarimol residues in comparison with the blank sample.  相似文献   
4.
Journal of Pest Science - Conservation biological control involves manipulation of the environment to enhance the effectiveness of natural enemies in controlling crop pests. In this study, we...  相似文献   
5.
Agroforestry Systems - Short-term production in silvopastoral systems is often limited due to inappropriate soil-fertility management. Sewage sludge fertilisation could enhance productivity of...  相似文献   
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The impact of atmospheric industrial emissions on secondary pollutant formation depends on many factors; one of the most important being the environmental setting in which the industry is located. The environmental setting affects an industry’s impact on ozone levels through both the air mass dispersion (a function of topography and wind patterns) and the emissions of organic volatile compounds (VOC) and nitrogen oxides (NO x ) in the area. This model-based study shows how the sensitivity of surface ozone changes with the choice of source location. For the analysis, seven points distributed along the Tinto–Guadalquivir Basin (in the Southwestern Iberian Peninsula) were selected. This area is characterized by the close proximity of natural environments and crop fields to cities, roads, and industrial areas with high NO x emissions. Natural VOC emissions represent more than 60% of the total non-methane volatile organic compounds emitted in the study area. The results reveal that the largest increases in ozone levels are produced when the industry is located both far away from NO x emission sources and near to biogenic VOC emissions. Furthermore, the highest increases over the hourly and 8-hourly maximums, as well as the highest accumulated daily values, are found in areas characterized by high VOC/NO x emission ratios and NO x sensitivity. The study of the recurrent meteorological patterns along with the distribution of chemical indicators of the O3–NO x –VOC sensitivity allows the determination of the industry’s geographical impact on ozone levels. This information enables air quality managers to decide the future location of an industry minimizing its impact on smog levels.  相似文献   
7.
The two enzymes involved in enzymatic browning reactions, polyphenol oxidase (PPO) and peroxidase (PO), have been partially purified and extracted from different fractions of beet root. PPO is mainly located in the membrane fraction, and it was also found in the soluble fraction. In both cases PPO was in its latent state. However, PO activity was higher in the soluble fraction than in the membrane fraction. Nevertheless, the highest values of specific activity for PO were obtained from the solubilized enzyme from acetone powders. Under native isoelectric focusing (IEF), several PPO isoenzymes were present in the pH range of 4.8-5.8. All of these isoenzymes shared a single band with a similar apparent mass under sodium dodecyl sulfate-polyacrylamide gel electrophoresis. PO was also analyzed by IEF, showing a complex isoenzyme pattern in all fractions. The characteristic basic PO isoenzyme of high pI found in both the soluble fraction and the solubilized enzyme from acetone powders was not detected in the membrane fraction. The kinetic characterization of PPO and PO from all fractions was carried out.  相似文献   
8.
The effect of different conditions of pea germination on dietary fiber (DF) composition was studied. Insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) were subjected to acid hydrolysis, and the resultant neutral sugars, uronic acids, and Klason lignin were quantified. Germinated peas exhibited significantly higher contents of total dietary fiber (TDF) than the raw sample, due to the increases of both DF fractions. Under darkness conditions, germination exhibited the highest contents of IDF and SDF. Decreasing IDF/SDF ratios showed that the carbohydrate changes did not take place to the same extent during germination, the SDF fraction being the most affected. The detailed chemical composition of fiber fractions reveals increases of cellulose in the IDF of germinated samples, whereas SDF exhibits a decrease of pectic polysaccharides and also increases of polysaccharides rich in glucose and mannose. The DF results were corroborated by a comparative examination of the cell wall carbohydrate composition.  相似文献   
9.
The persistence of two herbicides, simazine and terbuthylazine, and appearance of their principal dealkylated chloro-s-triazine metabolites have been studied in agricultural soil after the addition of urban sewage sludge as organic amendment. Both herbicides and metabolites were monitored during long-term laboratory incubation (140 days) and analyzed by gas chromatography with a nitrogen-phosphorus detector (GC-NPD). Residues were confirmed by gas chromatography with a mass selective detector (GC-MSD). A sonication microextraction method was used to extract the compounds. The organic amendments used were urban sewage sludge and the humic fraction of this sludge, to increase the organic matter content of the soil from 1% to 2%. For both compounds, simazine and terbuthylazine, the degradation began earlier in the amended soils. Simazine showed a higher dissipation rate than terbuthylazine, the percentage of the former at the end of the experiment being lower than 2% in all cases, while for terbuthylazine the corresponding percentage ranged from 5% to 46%. Organic amendment, mainly its humic fraction, caused a certain stabilization of terbuthylazine in the soil, but did not greatly influence the residual amount of simazine at the end of the experiment. The periodic aeration of the soil caused a greater degradation in the case of terbuthylazine. Only mono-deethylsimazine and deethylterbuthylazine were isolated from the soil during the time the experiment lasted, while the di-deethylated metabolite of simazine was not found.  相似文献   
10.
A case of a dwarf hamster with two progressively growing nodules on the right fore limb is described. These were excised following ineffective medical treatment and were submitted for histopathological examination, which revealed bacterial pseudomycetoma in both nodules. To the authors' knowledge this is the first reported case of bacterial pseudomycetoma in a dwarf hamster.  相似文献   
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