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61.
Tetsuya Yamada Keizi Suzuki Hirotaka Katuzaki Makoto Hisamatsu Takashi Komiya 《Starch - St?rke》1990,42(6):217-223
Native potato starch (moisture content 15%) was treated by twin screw extruder under four operating conditions with varying barrel temperatures (110°C–230°C). These modified starch samples were compared to native and drum-dried starch. Starch sample solution for gel chromatography was prepared by the three methods (acidic, alkaline, and neutral methods). They were subjected to gel chromatography on Toyopearl HW-75, and some difference was found among the three gel chromatographic patterns obtained from the same starch solution. This discrepancy among GPC patterns suggests formation of some types of anhydro-bonds between chains of amylopectin and or amylose in the extrusion process. Elevating barrel temperature increases degree of depolymerization. The size of fragments formed with the treatment is bigger than that of oligosaccharides but smaller than that of amylose. 相似文献
62.
The present study was aimed to investigate the cognitive enhancing and anti-oxidant activities of Inonotus obliquus (Chaga) against scopolamine-induced experimental amnesia. Methanolic extract of Chaga (MEC) at 50 and 100 mg kg (-1)doses were administered orally for 7 days to amnesic mice. Learning and memory was assessed by passive avoidance task (PAT) and Morris water maze (MWM) test. Tacrine (THA, 10 mg kg (-1), orally (p.o)) used as a reference drug. To elucidate the mechanism of the cognitive enhancing activity of MEC, the activities of acetylcholinesterase (AChE), anti-oxidant enzymes, the levels of acetylcholine (ACh) and nitrite of mice brain homogenates were evaluated. MEC treatment for 7 days significantly improved the learning and memory as measured by PAT and MWM paradigms. Further, MEC significantly reduced the oxidative-nitritive stress, as evidenced by a decrease in malondialdehyde and nitrite levels and restored the glutathione and superoxide dismutase levels in a dose dependent manner. In addition, MEC treatment significantly decreased the AChE activity in both the salt and detergent-soluble fraction of brain homogenates. Further, treatment with MEC restored the levels of ACh as did THA. Thus, the significant cognitive enhancement observed in mice after MEC administration is closely related to higher brain anti-oxidant properties and inhibition of AChE activity. These findings stress the critical impact of Chaga, a medicinal mushroom, on the higher brain functions like learning and memory. 相似文献
63.
The purpose of the present investigation was to test whether permanent skeletal muscle cells (rat L6 cells) could serve as
an in vitro model for α-tocopherol (αTocH) biodiscrimination studies. L6 cells were incubated in the presence of high density lipoprotein
(HDL), low density lipoprotein (LDL), and very low density lipoprotein (VLDL) labeled in the lipid moiety with either all-rac-or RRR-[14C]αTocH. These incubations were performed either in the absence or in the presence of exogenously added bovine lipoprotein
lipase (LPL) since skeletal muscle is one of the major expression sites of LPL in vivo. Time-dependent uptake studies (up to 24 h) in the absence of LPL have shown that equipotent doses of all-rac- and RRR-[14C]αTocH (1.36∶1) led to almost identical accumulation of the tracer, independent of the lipoprotein class used as αTocH carrier.
With regard to αTocH donor capacity, it appeared that HDL is the most potent αTocH donor, followed by LDL and VLDL. In the
presence of LPL, all-rac- and RRR-[14C]αTocH uptake was significantly enhanced (between two- and tenfold). Biodiscrimination studies using chiral high-performance
liquid chromatographic analysis with radiometric detection of the corresponding methyl ether derivatives on a Chiralcel OD
column have demonstrated that the 2S-and 2R-isomers of αTocH were taken up in a 1∶1 ratio by L6 cells independent of the absence or presence of LPL. In addition, we
have not observed biodiscrimination between the four 2R-isomers, i.e., there was no preferential accumulation of the RRR-isomer. These data suggest that L6 cells do not discriminate between different αTocH isomers and that the addition of endogenous
LPL significantly enhances the uptake of RRR- and all-rac-αTocH. 相似文献
64.
Masayuki Akiyama Masashi Tatsuzaki Tomomi Michishita Toshikazu Ichiki Masahiro Sumi Michio Ikeda Tetsuya Araki Yasuyuki Sagara 《Food and Bioprocess Technology》2012,5(5):1924-1938
To design a consumer-oriented package that complements the taste and aroma of ready-to-drink chilled-cup coffee beverages by using the food kansei model, the effects of the diameter and the color of drinking straws as well as the cognition terms of coffee on consumer sensory characteristics and preferences were investigated. Variance and factor analyses of the sensory scores for chilled-cup coffee with milk and sugar using straws of different diameters, as rated by consumer panelists, extracted two perceived factors (F1, contribution ratio 36.5%, and F2, 28.6%). A two-dimensional plot of the average F1 and F2 scores of 123 panelists showed that the perceived characteristics of the same taste and aroma varied according to the straw diameter. An image investigation of different straw colors and another sensory evaluation using “black,” “brown,” and “green” straws were also performed. A principal component analysis of the image data revealed that the sensory characteristics of coffee with milk and sugar were imaged from the straw color. The second evaluation suggested that the images of straw colors affected the sensory characteristics. In addition, cluster and multiple-comparison analyses of Internet research data from consumers regarding the cognition terms for coffee exhibited three clusters representing the cognitive characteristics of terms by consumers and by developers and the differences of attractiveness degree on the cognition terms due to the consumers’ personal attributes. These studies provide useful information for the development of packages of chilled-cup coffee beverages. 相似文献
65.
Tetsuya Nanba Asima Sultana Shouichi Masukawa Masaaki Haneda Junko Uchisawa Akira Obuchi Hideaki Hamada 《Topics in Catalysis》2009,52(13-20):1766-1770
Selective catalytic reduction of NO x by NH3 over Cu–FER and Cu–ZSM-5 in the presence of n-decane and SO2 was investigated. NO x conversion over Cu–ZSM-5 decreased in the presence of n-decane, owing to inhibition of the active sites by coke formation. In contrast, coke formation was negligible over Cu–FER, which maintained its NO x conversion activity even in the presence of decane. Coke formation was negligible over H–ZSM-5 and H–FER supports, which suggests that Cu species were involved in coke formation. Temperature-programmed reduction by H2 and electron spin resonance spectroscopy indicated that [Cu–O–Cu]2+ was probably the Cu species involved in coke formation over Cu–ZSM-5. 相似文献
66.
Grain growth in a high-purity ZnO and for the same ZnO with Bi2 O3 additions from 0.5 to 4 wt% was studied for sintering from 900° to 1400°C in air. The results are discussed and compared with previous studies in terms of the phenomenological kinetic grain growth expression: G n — G n 0 = K 0 t exp(— Q/RT ). For the pure ZnO, the grain growth exponent or n value was observed to be 3 while the apparent activation energy was 224 ± 16 kJ/mol. These parameters substantiate the Gupta and Coble conclusion of a Zn2+ lattice diffusion mechanism. Additions of Bi2 O3 to promote liquidphase sintering increased the ZnO grain size and the grain growth exponent to about 5, but reduced the apparent activation energy to about 150 kJ/mol, independent of Bi2 O3 content. The preexponential term K 0 was also independent of Bi2 O3 content. It is concluded that the grain growth of ZnO in liquid-phase-sintered ZnO-Bi2 O3 ceramics is controlled by the phase boundary reaction of the solid ZnO grains and the Bi2 O3 -rich liquid phase. 相似文献
67.
Masaki Honda Hakuto Kageyama Takashi Hibino Rungaroon Waditee‐Sirisattha Tetsuya Fukaya Yoshiaki Hayashi Motonobu Goto 《European Journal of Lipid Science and Technology》2020,122(3)
Z‐isomers of lycopene exhibit higher bioavailability and antioxidant capacity than those of the all‐E‐isomer. Therefore, it is important to develop an efficient and environmentally friendly procedure for Z‐isomerization. The current methods for Z‐isomerization of (all‐E)‐lycopene use toxic chemicals such as organic solvents and catalysts. This study is aimed to develop a chemical‐free method for Z‐isomerization of (all‐E)‐lycopene in tomato powder by hot air and superheated steam heating. The Z‐isomerization reaction is promoted by heating above the melting point of lycopene. When heated with superheated steam, the thermal decomposition of lycopene is suppressed compared to that when heated with hot air. When tomato powder is heated at 240 °C for 5 min by superheated steam, the total Z‐isomer content and remaining lycopene are 69.0% and 90.7%, respectively, while with hot air heating, the total Z‐isomer content and remaining lycopene are 69.9% and 68.0%, respectively. These results indicate that the thermal Z‐isomerization of lycopene occurs in the molten state and heating in a low oxygen atmosphere suppresses the thermal decomposition of lycopene. Practical Applications: Tomato powder rich in lycopene Z‐isomers is an important ingredient for the food and animal feed industries. Since Z‐isomers of lycopene are more soluble in solvents including ethanol which is a low‐toxicity and environmentally friendly solvent, the efficiency of lycopene extraction with ethanol can be improved by using the Z‐isomer‐rich tomato powder as a raw material. The obtained Z‐isomer‐rich extract has a high added value because the Z‐isomers have higher bioavailability and antioxidant capacity than those of the all‐E‐isomer. In addition, since lycopene Z‐isomers exhibit higher accumulation efficiency and better color improvement in hen egg yolks than those of the all‐E‐isomer, Z‐isomer‐rich tomato powder is an effective animal feed. 相似文献
68.
An efficient and compact catalytic membrane reactor for reforming of CH4 was developed by integrating a hydrogen perm-selective silica membrane with an Rh/-Al2O3 catalyst layer. The catalytic layer was sandwiched between the outer surface of the -Al2O3 support tube and the silica membrane with an aim of improving the heat and mass transfer rates through the system and to simplify the reactor geometry. The system showed improved efficiency for reforming of CH4 at comparatively lower operating temperatures and steam to C molar ratios than the conventional fixed-bed steam reforming systems. Under optimized conditions, a nearly 25-30% improvement from the equilibrium conversion level was achieved as a result of abstraction of hydrogen from the product stream by the silica membrane integrated with the catalyst layer. The performance of the system was evaluated as a function of various process parameters. Because of the compactness and efficiency, the present system emerges as a promising alternative to the conventional membrane reactors, which possess separate catalytic and membrane units. 相似文献
69.
A GIS-based DRASTIC model for assessing aquifer vulnerability in Kakamigahara Heights, Gifu Prefecture, central Japan 总被引:14,自引:0,他引:14
Vulnerability assessment to delineate areas that are more susceptible to contamination from anthropogenic sources has become an important element for sensible resource management and land use planning. This contribution aims at estimating aquifer vulnerability by applying the DRASTIC model as well as utilizing sensitivity analyses to evaluate the relative importance of the model parameters for aquifer vulnerability in Kakamigahara Heights, Gifu Prefecture central Japan. An additional objective is to demonstrate the combined use of the DRASTIC and geographical information system (GIS) as an effective method for groundwater pollution risk assessment. The DRASTIC model uses seven environmental parameters (Depth to water, net Recharge, Aquifer media, Soil media, Topography, Impact of vadose zone, and hydraulic Conductivity) to characterize the hydrogeological setting and evaluate aquifer vulnerability. The western part of the Kakamigahara aquifer was dominated by "High" vulnerability classes while the eastern part was characterized by "Moderate" vulnerability classes. The elevated north-eastern part of the study area displayed "Low" aquifer vulnerability. The integrated vulnerability map shows the high risk imposed on the eastern part of the Kakamigahara aquifer due to the high pollution potential of intensive vegetable cultivation. The more vulnerable western part of the aquifer is, however, under a lower contamination risk. In Kakamigahara Heights, land use seems to be a better predictor of groundwater contamination by nitrate. Net recharge parameter inflicted the largest impact on the intrinsic vulnerability of the aquifer followed by soil media, topography, vadose zone media, and hydraulic conductivity. Sensitivity analyses indicated that the removal of net recharge, soil media and topography causes large variation in vulnerability index. Moreover, net recharge and hydraulic conductivity were found to be more effective in assessing aquifer vulnerability than assumed by the DRASTIC model. The GIS technique has provided efficient environment for analyses and high capabilities of handling large spatial data. 相似文献
70.
Yusuke Furuta Hiroyuki Nishikawa Takahiro Satoh Yasuyuki Ishii Tomihiro Kamiya Ryota Nakao Satoshi Uchida 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(12-13):2285-2288
Fabrication of high-aspect-ratio microstructures was performed by proton beam writing (PBW) using a microbeam line at Takasaki Ion Accelerators for Advanced Radiation Application (TIARA), JAEA Takasaki, JAPAN. As one of the applications of the high-aspect-ratio structures micro-machined by PBW, we utilized the high-aspect pillars for electric-micro filters of microbes such as Escherichia coli and Yeast based on the dielectrophoretic force. The filter is equipped with high-aspect pillars with a height of ~20 μm and a diameter of ~1 μm on a glass plate. Evaluation of the dielectrophoresis (DEP) device for capturing E. coli and Yeast was made using either observation by optical microscope or photoluminescence (PL) measurements. 相似文献