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31.
We profiled and quantified glucosinolates, anthocyanins, carotenoids, and other secondary metabolites in the skin and flesh of pale green and purple kohlrabis. Analysis of these distinct kohlrabis revealed the presence of 8 glucosinolates, 12 anthocyanins, 2 carotenoids, and 7 phenylpropanoids. Glucosinolate contents varied among the different parts and types of kohlrabi. Glucoerucin contents were 4-fold higher in the flesh of purple kohlrabi than those in the skin. Among the 12 anthocyanins, cyanidin 3-(feruloyl)(sinapoyl) diglucoside-5-glucoside levels were the highest. Carotenoid levels were much higher in the skins than the flesh of both types of kohlrabi. The levels of most phenylpropanoids were higher in purple kohlrabi than in pale green ones. trans-Cinnamic acid content was 12.7-fold higher in the flesh of purple kohlrabi than that in the pale green ones. Thus, the amounts of glucosinolates, anthocyanins, carotenoids, and phenylpropanoids varied widely, and the variations in these compounds between the two types of kohlrabi were significant.  相似文献   
32.
Carbohydrate digestion by α-glucosidase and subsequent glucose uptake at the brush border are critical for postprandial blood glucose control. Any specific inhibitors are useful as hyperglycemia modulating agents. In this study, it was postulated that an array of active components in mulberry leaf extract (MLE) may provide higher potency in inhibiting intestinal glucose absorption compared to the single component 1-deoxynojirimycin (DNJ), which is recognized as a promising inhibitor of intestinal glucose absorption. Both MLE and DNJ were active in inhibiting α-glucosidase. However, in Caco-2 cells, only MLE showed significant inhibition of 2-deoxyglucose uptake, whereas DNJ was ineffective. For glucose loading, co-administration of MLE resulted in potent inhibitions of glucose responses compared to those by DNJ in Sprague Dawley (SD) rats, but this was not found for maltose loading. These novel findings add evidence that the unabsorbed phytochemicals in MLE compete with glucose for intestinal glucose transporters, but DNJ itself does not. We also evaluated the timing of MLE consumption. By administering MLE for 30 min before glucose loading, the incremental area under the curve (IAUC) was significantly lowered in the rats, as compared to a simultaneously administered group. Similarly, cellular glucose uptake was significantly reduced in Caco-2 cells following pretreatment.  相似文献   
33.
大豆蛋白-多糖复合物结构与性能及其稳定性研究   总被引:1,自引:0,他引:1  
以大豆分离蛋白(SPI)、阿拉伯树胶(GA)及卡拉胶(CA)为原料,经物理混合成功制备不同多糖与SPI复合物,考察不同添加量(SPI与GA/CA质量比为20、15、10、5)对蛋白-多糖复合物结构、性能变化趋势及其乳液稳定性的影响规律,最终探明蛋白与不同多糖复合物的相互作用机制;运用红外光谱、荧光光谱及电子显微镜解析不同复合物的结构特征,采用乳化特性、粒径、Zeta-电位、表面疏水性等指标明确不同复合物的理化特性,并通过探讨不同复合物乳液的乳化活性、乳化稳定性、表观粘度及乳析指数明晰其稳定特性。结果表明,两种多糖在酸性条件下可与SPI生成复合物,并且当SPI与CA质量比为20时,复合物的Zeta-电位最高,为(20.47±0.82) mV,平均粒径最小,为(1.37±0.01)μm,分布均匀,乳化活性指数最高,为(106.46±4.75) m2/g,乳化稳定性指数为(145.33±8.53) min,此时复合乳液的稳定性较好,CA的加入显著降低SPI内源荧光强度并改变SPI的二级结构,SPI与CA结合形成了稳定的复合物。  相似文献   
34.
To understand wood colonization by sapstain fungi and their potential biocontrol agents, it is necessary to differentiate these organisms directly on their natural substrates. In the present study the feasibility of transforming with the green fluorescent protein (GFP), the sapstain fungus Ophiostoma piceae and a potential biocontrol agent Cartapip®, an Ophiostoma piliferum albino strain was assessed. Transformants of the two fungal species were screened by polymerase chain reaction and Southern blot analyses. The GFP was expressed in spores, synnemata and mycelia of the transformants grown in artificial media or wood. The growth, pigmentation and wood colonization of the transformants were similar to that of the non‐transformants, suggesting that the presence of the gfp gene had no negative effect on the biology of the transformants. Using fluorescence and confocal microscopy, the GFP‐expressing fungi were easily differentiated from the wild‐type strains and other fungal species in wood, even 4 months after inoculation. The results show that the use of the GFP system is feasible to monitor Ophiostoma fungi in wood.  相似文献   
35.
中韩古典园林是传统文化的结晶,并且是东方园林的两枝奇葩。中国园林与韩国园林属于本源和分支的关系,韩国园林很多方面传承了中国园林的造园手法及艺术特征;然而不同的自然人文环境也使两种园林风格迥异,在园林中起着十分重要构景作用的置石也不例外。本文试从置石的形态与应用手法对中韩园林的不同作一些分析。  相似文献   
36.
37.
In trace metal (TM)-contaminated agricultural soils, management of TM availability is important for safe crop production. In addition, maintenance or improvement of soil quality is vital for sustainable crop cultivation. Decreased TM phytoavailability and increased soil quality can be achieved by the application of various immobilizing agents to soil, which can supply both macronutrients and organic matter. This study investigated the long-term influences of four common immobilizing agents on so...  相似文献   
38.
Activated carbon-coated electrode was developed and applied in electrostatic precipitator to remove volatile organic compound gases simultaneously with dust particles from a contaminated air. The activated carbon coating mixture was made up of powdered activated carbon (AC), carbon black (CB), and polyvinyl acetate (PVA), and methanol was added as a solvent to control the thickness of the mixture for best coating performance. During the coating process, the Brunauer-Emmett-Teller (BET) surface decreased to 86% of the original AC while pore volume percentages of macro pore increased, compared to micro- and meso-sized pores. The adsorption isotherm of benzene, toluene, ethyl benzene, and xylene (BTEX) gases onto the original AC and AC coating mixture (AC thoroughly mixed with PVA and methanol for coating and powdered again after dry) were tested and compared to each other, and it was found that both isotherm were best fitted to Freundlich and Langmuir isotherm with the order of adsorption capacities; ethyl benzene?>?m-xylene?>?toluene?>?benzene. The difference between adsorption capacities was clearer with the absorbent AC but became little with the AC coating mixture. In removing BTEX at increasing linear velocities up to 6.7 cm/s, it appeared that the surface area of AC electrode was directly proportional to its removal rate of BTEX. The thermal desorption was applied to regenerate the AC electrode, and 200 °C was found to be most efficient for benzene desorption, but higher temperature would be required for entire BTEX gases desorption.  相似文献   
39.
Ballast seawater is considered globally as a major vector for invasions of non-indigenous organisms. Several technologies have been tested for their ability to remove organisms from ballast water. In the present study, we constructed a novel pulsed high-voltage discharge (PHVD) system that could operate in either high current mode with several hundred amperes or shockwave generating mode with relatively lower current in seawater. In laboratory-scale experiments, the PHVD system with shockwave-generating mode was found to be more effective in killing zooplankton (1.9- to 4.0-fold) and phytoplankton (3.3-fold) than high current mode at discharge with 300–500 pulses at 7.1 kV. Further experiments were carried out at different voltages and pulse-numbers to examine effects of the shockwave-generating PHVD system on viabilities of one zooplankton larva, two phytoplankton species, and an indicator bacterium suspended in seawater in a static chamber. For zooplankton, live cells were not detected at discharge with 400 pulses at 13 kV. For phytoplankton, the initial live cells of a dinoflagellate was decreased by 77?±?0.5%, and the initial chl a concentration of a diatom was decreased by 76?±?6% at discharge with 700 pulses at 13 kV. For an indicator bacterium Escherichia coli, live cells were not detected at discharges with 200 or 700 pulses at 13 kV. Measurements of ATP content of organisms showed congruent results with those obtained by the above methods, suggesting it may be a rapid method for evaluating treatment efficiency. Though further scale-up studies are necessary, these results suggest that the PHVD system have a high potential for applying to ballast seawater treatment.  相似文献   
40.
6[8'(Z)-pentadecenyl]salicylic acid, otherwise known as anacardic acid (C15:1), inhibited the linoleic acid peroxidation catalyzed by soybean lipoxygenase-1 (EC 1.13.11.12, type 1) with an IC50 of 6.8 microM. The inhibition of the enzyme by anacardic acid (C15:1) is a slow and reversible reaction without residual activity. The inhibition kinetics analyzed by Dixon plots indicates that anacardic acid (C15:1) is a competitive inhibitor and the inhibition constant, KI, was obtained as 2.8 microM. Although anacardic acid (C15:1) inhibited the linoleic acid peroxidation without being oxidized, 6[8'(Z),11'(Z)-pentadecadienyl]salicylic acid, otherwise known as anacardic acid (C15:2), was dioxygenated at low concentrations as a substrate. In addition, anacardic acid (C15:2) was also found to exhibit time-dependent inhibition of lipoxygenase-1. The alk(en)yl side chain of anacardic acids is essential to elicit the inhibitory activity. However, the hydrophobic interaction alone is not enough because cardanol (C15:1), which possesses the same side chain as anacardic acid (C15:1), acted neither as a substrate nor as an inhibitor.  相似文献   
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