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961.
Moriyama T Shindoh K Taguchi Y Watanabe H Yasui A Joh T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(3):145-149
Milled rice and bran were prepared from brown rice (Oryza sativa japonica) using a commercial scale rice-mill to investigate the changes in cadmium (Cd) content caused by the milling process. Rice sample solution was prepared by microwave digestion using HNO3 and HF, then analyzed by ICP-MS. Cd was measured at m/z 114 in interference correction with MoO and Sn. The digestion method was validated with 4 kinds of certified reference material of "rice flour". We found that the Cd content was reduced only slightly by the milling process. When the Cd concentration of brown rice was regarded as 100, the relative content of the milled rice was 97 (average of 6 samples). In addition, the reduction of the Cd content was only slight when milled rice was processed to "wash-free" rice. The relative Cd content of the bran was 139 when that of brown rice was regarded as 100. These results support the hypothesis that the Cd content is not greatly decreased by the milling process. 相似文献
962.
Hydrogen and ethanol production from glycerol-containing wastes discharged after biodiesel manufacturing process 总被引:5,自引:0,他引:5
Ito T Nakashimada Y Senba K Matsui T Nishio N 《Journal of Bioscience and Bioengineering》2005,100(3):260-265
H2 and ethanol production from glycerol-containing wastes discharged after a manufacturing process for biodiesel fuel (biodiesel wastes) using Enterobacter aerogenes HU-101 was evaluated. The biodiesel wastes should be diluted with a synthetic medium to increase the rate of glycerol utilization and the addition of yeast extract and tryptone to the synthetic medium accelerated the production of H2 and ethanol. The yields of H2 and ethanol decreased with an increase in the concentrations of biodiesel wastes and commercially available glycerol (pure glycerol). Furthermore, the rates of H2 and ethanol production from biodiesel wastes were much lower than those at the same concentration of pure glycerol, partially due to a high salt content in the wastes. In continuous culture with a packed-bed reactor using self-immobilized cells, the maximum rate of H2 production from pure glycerol was 80 mmol/l/h yielding ethanol at 0.8 mol/mol-glycerol, while that from biodiesel wastes was only 30 mmol/l/h. However, using porous ceramics as a support material to fix cells in the reactor, the maximum H2 production rate from biodiesel wastes reached 63 mmol/l/h obtaining an ethanol yield of 0.85 mol/mol-glycerol. 相似文献
963.
Miyoshi K Matsuura H Kumon T Matsuda K Yoshikawa T Bamba T Harada K Hirata K 《Journal of Bioscience and Bioengineering》2011,112(1):75-78
We isolated a Chlamydomonas gene encoding putative γ-glutamyl kinase (GK), an enzyme that catalyzes the first step of proline biosynthesis. Using an Escherichia coli auxotroph and a purified recombinant protein, we show that Chlamydomonas GK is a functional GK. The sensitivity of this kinase to feedback inhibition by proline was lower than in that of microbial GKs previously reported. 相似文献
964.
Pham Van Hung Tomoko Maeda Masaya Fujita Naofumi Morita 《Journal of the science of food and agriculture》2007,87(13):2538-2543
BACKGROUND: Waxy wheat, a new kind of genetically back‐crossed wheat, was applied to make whole bread in this study. Dough properties and bread quality of the whole waxy wheat flour, which was milled from 100% whole grains containing bran and germ, were determined. RESULTS: Whole waxy wheat had lower protein and lipid contents but higher dietary fiber content than whole regular wheat flour. Pasting temperature and viscosity of the whole waxy wheat flour were significantly lower than those of the whole regular wheat. However, the white wheat flour milled from wheat grains with 48% recovery had significantly higher peak viscosity than the whole waxy wheat. Bread made from the whole waxy wheat flour was significantly softer than that from the whole regular wheat flour during storage. However, bread made from whole waxy wheat had significantly lower specific volume than that from the white waxy flour because of the high amount of dietary fiber. Addition of cellulase increased paste viscosity, lowered dough mixing properties and reduced the firmness of the bread. The addition of pentosanase also increased paste viscosity, lowered dough mixing properties, improved loaf volume of bread but increased the firmness of breadcrumbs, while the addition of α‐amylase only increased final viscosity of flour and did not affect dough properties and bread qualities of whole waxy wheat flour. CONCLUSION: As a result, waxy wheat shows superior properties for making whole breads. Additional enzymes are also necessary to improve bread quality and nutritive values of whole waxy bread. Copyright © 2007 Society of Chemical Industry 相似文献
965.
Amakura Y Tsutsumi T Sasaki K Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(6):316-320
We determined the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (Co-PCBs) in three types of fast foods [(1) seventeen hamburgers and two hot dogs, (2) six portions of fried potatoes and (3) three chicken products] obtained from fast food shops or convenience stores in Japan. All samples tested showed low toxic equivalent quantity (TEQ) levels of dioxins in the range of 0.001-0.083 pg-TEQ/g wet weight (0.006-0.053 pg-TEQ/g for hamburgers and hot dogs, 0.001-0.083 pg-TEQ/g for fried potatoes and 0.053-0.065 pg-TEQ/g for chicken products). The congener profile in hamburgers and hot dogs suggested that the total TEQ was mainly determined by Co-PCBs, especially by 3,3',4,4',5-PeCB (#126), which accounted for 44% of the total TEQ value. Findings for animal foods such as beef and cheese were consistent with this result. For fried potatoes, PCDD/Fs accounted for 94% of the total TEQ value, and 2,3,4,7,8-PeCDF accounted for 32% of PCDD/Fs. Dioxins in the chicken products consisted of 3,3',4,4',5-PeCB (#126) and 1,2,3,7,8-PeCDD, which accounted for 23% and 21% of the total TEQ, respectively. If an adult (50 kg weight) eats 150 g of hamburger, 100 g of potatoes and 150 g of chicken, the daily intake is estimated to be 0.299 pg-TEQ/kg b.w./day using the average values (0.022, 0.028 and 0.059 pg-TEQ/g, respectively) obtained in this study. This value corresponds to 7.5% of the tolerable daily intake (TDI) for PCDD/Fs and Co-PCBs in Japan. 相似文献
966.
Takao Watanabe Yoshiyuki Izaki Yoshihiro Mugikura Hiroshi Morita Masahiro Yoshikawa Makoto Kawase Fumihiko Yoshiba Koichi Asano 《Journal of power sources》2006,160(2):868-871
MCFCs can utilize CO rich and H2 lean fuel, such as gasified biomass or gasified waste as a Pt catalyst is not used and Pt poisoning by CO does not occur. This feature has become very important due to the worldwide CO2 depression requirements. CRIEPI has developed MCFC technologies in line with a governmental program, which mainly focused on natural gas fuel. However, CRIEPI has recently been focussing on technologies for various fuel applications. Single cells and stacks were tested with various gas compositions and showed stable performance even with high CO and high fuel utilization conditions. Gasified biomass or waste can contain many kinds of impurities such as H2S, HCl, HF, NH3, etc. The effects of these impurities were taken into account for single cells, and the permissible limits were estimated. 相似文献
967.
We have developed a ray-tracing simulation procedure for optically isotropic gradient refractive-index media. The procedure can take discrete points of arbitrary distribution for the definition of refractive-index distributions and lens surfaces. It is useful for simulating ray trajectories in real lens systems. The procedure is applied to a ray-tracing simulation of the Luneburg lens and a radial gradient optical fiber. The simulation results are compared with the analytical solutions, and it is shown that they are in precise agreement. 相似文献
968.
Youngjo Kang Bahman Sahebkar Piotr R. Scheller Kazuki Morita Du Sichen 《Metallurgical and Materials Transactions B》2011,42(3):522-534
The behaviors of several types of inclusions at a high temperature were examined using a confocal scanning laser microscope
(CSLM, 1LM21H/SVF17SP). Although alumina inclusions tended to impact on each other, agglomerate, and grow quickly, no other
inclusion type, such as spinel as well as solid and liquid calcium aluminate, was observed to attract each other. The results
of confocal microscope study were compared with the industrial investigation. For this purpose, many steel samples were taken
at different stages of ladle treatment. The samples were analyzed by scanning and light optical microscopes. Approximately
50,000 inclusions of several types were examined. Only alumina inclusions were attracted to each other and agglomerate. No
agglomeration by attractive behavior was observed in the other types of inclusions, including liquid inclusions. Both the
industrial data and the in situ observation by CSLM indicate that, although the attraction force and the agglomeration play a significant role in the growth
of alumina inclusions, the agglomeration of spinel and calcium aluminate inclusions does not need special consideration in
ladle treatment. The agglomeration of liquid calcium aluminate inclusions took place only when they occasionally met as a
result of external force, which led to low collision probability. However, the agglomeration of the liquid calcium aluminate
inclusions along with alumina particles could be detrimental in the casting process. 相似文献
969.
Song Chen Xuetao Shi Hiromi Morita Jie Li Nobuhiro Ogawa Toshiyuki Ikoma Satoshi Hayakawa Yuki Shirosaki Akiyoshi Osaka Nobutaka Hanagata 《Science and Technology of Advanced Materials》2011,12(6)
Silica nanotube fibrous meshes were fabricated as multiple functional matrices for both delivering bone morphological protein-2 (BMP-2) and supporting osteoblast attachment and proliferation. The meshes were fabricated via a collagen-templated sol–gel route and consisted of tubular silica with open ends. BMP-2 was loaded to the meshes by soaking in BMP-2 solution. The meshes effectively enabled the attachment and proliferation of osteoblast MC3T3-E1 cells and delivered bioactive BMP-2 to stimulate cell differentiation. These results demonstrate the potential use of the meshes in bone generation applications. 相似文献
970.
Sasaki K Morita M Sasaki D Nagaoka J Matsumoto N Ohmura N Shinozaki H 《Journal of Bioscience and Bioengineering》2011,112(5):469-472
Protein is a major component of organic solid wastes, and therefore, it is necessary to further elucidate thermophilic protein degradation process. The effects of hydrogenotrophic methanogens on protein degradation were investigated using the proteolytic bacterial strain CT-1 that was isolated from a methanogenic thermophilic (55°C) packed-bed reactor degrading artificial garbage slurry. Strain CT-1 was closely related to Coprothermobacter proteolyticus, which is frequently found in methanogenic reactors degrading organic solid wastes. Strain CT-1 was cultivated in the absence or presence of Methanothermobacter thermautotrophicus by using 3 kinds of proteinaceous substrates. Degradation rates of casein, gelatin, and bovine serum albumin were higher in co-cultures than in monocultures. Strain CT-1 showed faster growth in co-cultures than in monocultures. M. thermautotrophicus comprised 5.5-6.0% of the total cells in co-culture. Increased production of ammonia and acetate was observed in co-cultures than in monocultures, suggesting that addition of M. thermautotrophicus increases the products of protein degradation. Hydrogen produced in the monocultures was converted to methane in co-cultures. These results suggest that thermophilic proteolytic bacteria find it favorable to syntrophically degrade protein in a methanogenic environment, and that it is important to retain hydrogen-scavenging methanogens within the reactor. 相似文献