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101.
Do Carmo Barbosa Mendes De Vasconcelos M Bennett RN Rosa EA Ferreira Cardoso JV 《Journal of agricultural and food chemistry》2007,55(9):3508-3516
Chestnut (Castanea sativa) is an important basic food in rural diets and a major starch crop used in a similar way to potatoes. Chestnuts are a fundamental economic resource in the "chestnut regions" not only for the fruit but also for the chestnut wood. Chestnuts have become increasingly important with respect to human health, for example, as an alternative gluten-free flour source. Chestnuts are also a rich source of other beneficial compounds, but there have been few studies on the composition during processing. In this study, we analyzed the chemical composition of three Portuguese cultivars at different stages of industrial processing. The chestnut cultivars were Longal, Judia, and Martaínha. All three cultivars had high moisture contents but were low in ash, crude fat, and crude protein contents, with high starch and low fiber contents. The free amino acid contents, including various essential amino acids, varied depending on the cultivar. All three cultivars also had a significant content of polyphenolics with gallic acid; ellagic acid was predominant among hydrolyzable and condensed tannins. Many of these compounds are known to exert significant positive effects on human health. The one-way analysis of variance for fresh chestnut shows significant differences among the three cultivars for most of the studied parameters. The same statistical analysis applied to each one of the two cultivars (Judia and Longal) sampled for the four processing steps analyzed indicates a significant effect of this factor in practically all of the constituents. On the other hand, the two-way analysis of variance shows that, besides the residual, the processing step and the interaction cultivar x processing step were the factors that more contributed for the total variation observed in the constituents analyzed, while the contribution of cultivar was much less significant. 相似文献
102.
以辣椒细胞质雄性不育系9704A和8214A为试材,取无菌苗真叶进行培养。研究了不同浓度的IAA,6-BA和GA3对不定芽的诱导和伸长作用,结果表明:MS+6-BA5.0 mg/L +IAA1.0 mg/L有利于不定芽的诱导。MB+IAA1.0 mg/ L +6-BA3.0 mg/L + GA32.0 mg/L +AgNO310.0 mg/L有利于芽的伸长。将2.0 cm以上的芽转入生根培养基诱导不定根发现:1/2Ms+IAA0.3~0.5 mg/L有利于不定根的诱导。 相似文献
103.
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106.
W. De Boer M. P. J. Hundscheid J. M. T. Schotman S. R. Troelstra H. J. Laanbroek 《Biology and Fertility of Soils》1993,15(2):120-126
Summary The effect of liming on in-situ N transformations was studied in two stands of different ages of each of Scots pine (Pinus sylvestris L.), Douglas fir [Pseudotsuga menziesii (Mirb.) Franco], and common oak (Quercus robur L.). The stands were located on acid sandy soils in an area with high atmospheric N input. The organic matter of the upper 10-cm layer of the soil, including the forest floor, had a relatively high N content (C: N ratio <25) in all stands. Using a sequential core technique, N transformations were measured in both control plots and plots that had been limed 3 years previously with 3 t ha-1 of dolomitic lime. Limed plots had a higher net NO
inf3
sup-
production and a higher potential for NO
inf3
sup-
leaching than the controls in all stands except that of the younger oak. Net N mineralization did not differ significantly between limed and control plots in oak stands and younger coniferous stands but was significantly lower in the limed plots of the older coniferous stands. It is concluded that long-term measurements of net N mineralization in limed forest soils are needed to evaluate the effect of liming with respect to the risk of groundwater pollution. 相似文献
107.
Cultrone G. De la Torre M. J. Sebastian E. M. Cazalla O. Rodriguez-Navarro C. 《Water, air, and soil pollution》2000,119(1-4):191-207
The weathering of different brick samples ina range of aggressive environments has been studied.Brick samples were prepared using two clay types (fromGranada, Spain), different additives, and a range offiring temperatures (850–1100 °C). The brickscompositional and textural characteristics wereevaluated using XRD, SEM, hydric tests and mercuryintrusion porosimetry (MIP). The samples weresubjected to accelerate aging, including wet-dry,freeze-thaw and salt crystallization cycles. The decayof the bricks in polluted atmospheres was simulated ina static chamber containing sulfur dioxide (SO2)at 25 °C and 50% relative humidity. Samplesfired at 1000 °C proved to be the most durable,with better hydric behavior (fast drying and slowwater absorption) and fewer micropores. However, theywere not suitable for salt-rich environments (badperformance in the salt decay test). Samples fired at850 °C turned out to be more resistant to saltdecay, but they showed a poor hydric behavior (slowdrying and rapid water absorption) and littleresistance to freeze-thaw and wet-dry cycles. Samplesfired at 1100 °C had good hydric behavior, theyperformed well in the salt decay test, but they didnot perform as well as the samples fired at1000 °C in most accelerated aging tests. Gypsumformed on all the brick samples submitted to SO2atmosphere regardless exposure time (e.g. gypsumappears following just 24 h of exposure),composition, or firing temperature. Samples withdeposited particulate matter collected from vehicleexhausts (diesel, as well as leaded and non-leadedgasoline motor cars) resulted in the fastest gypsumdevelopment and greater abundance. On the other hand,the blank samples, and the samples withpollution-derived dust collected from historicalbuildings showed little gypsum development. Theimplications of these results in historicalbrick-building preservation in a range of aggressiveenvironments, and in polluted atmospheres inparticular, are discussed. 相似文献
108.
109.
Development of an indirect competitive ELISA for flumequine residues in raw milk using chicken egg yolk antibodies 总被引:3,自引:0,他引:3
Van Coillie E De Block J Reybroeck W 《Journal of agricultural and food chemistry》2004,52(16):4975-4978
To detect flumequine in raw milk, an indirect competitive enzyme-linked immunosorbent assay (ELISA) was developed. By carbodiimide conjugation, flumequine was conjugated to cationized bovine serum albumin (cBSA-flumequine) and to cationized ovalbumin (cOVA-flumequine). For the immunization of chickens, cBSA-flumequine was used, which allowed the isolation of specific chicken egg yolk immunoglobulins (IgY) for flumequine. As the coating antigen in the immunoassay, cOVA-flumequine was used. In the indirect competitive assay, standard flumequine was incubated together with the anti-flumequine antibodies. The antibody by which the lowest concentration of free flumequine that gives 50% inhibition of binding (IC50) was found in aqueous dilution was further tested for the applicability to detect flumequine in raw milk. An IC50 level in milk was reached that was about 5 times lower than in aqueous solution. So flumequine can be detected directly in raw milk at maximum residue level (50 microg/kg). No cross-reactivity was noticed with various related quinolones. 相似文献
110.
长期免耕水稻田土壤的生物特征研究 总被引:40,自引:8,他引:40
对经过 10年半旱式免耕定位试验的水稻土主要微生物类群数量和微生物生物量的变化进行对比研究 ,结果表明 :实行半旱式厢作及垄作免耕法能够迅速地提高土壤有机质、全氮、全磷和速效氮、磷的水平 ;微生物数量和微生物生物量变化一般存在季节性规律 :春季高 ,夏季至夏末降低 ;各处理土体上层和下层 (0~ 7.5 cm,7.5~15 cm)的基本肥力特征及微生物特征无明显区别 ;免耕处理土壤 ,其微生物的季节性变幅较小 ,垄上或厢上土壤微生物生物量甚至表现反季节性 ,整个生长季节内稳中有升 ,有利于土壤有机物质的转化和土壤肥力的发挥 相似文献