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101.
Ruvini Liyanage Kyu‐Ho Han Ken‐ichiro Shimada Mitsuo Sekikawa Yoshihiko Tokuji Kiyoshi Ohba Keiko Sasaki Barana Chaminda Jayawardana Takashi Shimizu Michihiro Fukushima 《European Journal of Lipid Science and Technology》2009,111(9):884-892
We examined the effect of potato peptides (PPC) in rats fed a cholesterol‐enriched diet, in comparison with two cholesterol‐enriched diets containing soy peptides (SPC) or casein (CNC), and a cholesterol‐free diet containing casein (CN) for 4 weeks. The serum non‐high‐density lipoprotein (HDL) cholesterol level was lower in the PPC‐ (–18.39%) and SPC‐fed (–32.76%) groups (p <0.05) than in the CNC‐fed group at the end of the feeding period. The low‐density lipoprotein receptor mRNA level in the PPC‐fed group, and cholesterol 7α‐hydroxylase and scavenger receptor class B type 1 mRNA levels in the SPC‐fed group, were higher (p <0.05) than in the CN‐ and CNC‐fed groups. Faecal neutral sterol and caecal short‐chain fatty acid concentrations in the PPC‐ and SPC‐fed groups were higher (p <0.05) than in the CN‐ and CNC‐fed groups. The faecal total acidic sterol concentration was higher in the SPC‐fed group than in the CN‐ and PPC‐fed groups. Caecal anaerobe and Bifidobacterium populations were higher (p <0.05) in the PPC‐ and SPC‐fed groups than in the CN‐fed group. This study suggests that potato peptides, as soy peptides, alter caecal fermentation and steroid absorption and reduce the serum non‐HDL cholesterol level in rats fed cholesterol. 相似文献
102.
Shimizu Sakayu Akimoto Kengo Kawashima Hiroshi Shinmen Yoshifumi Yamada Hideaki 《Journal of the American Oil Chemists' Society》1989,66(2):237-241
The mycelial dihomo-γ-linolenic acid content of an arachidonic acid-producing fungus,Mortierella alpina 1S-4, was found to increase, with an accompanying marked decrease in its arachidonic acid content, on cultivation with sesame
oil. The resultant mycelia were found to be a rich source of dihomo-γ-linolenic acid. This unique phenomenon was suggested
to be due to specific repression of the conversion of dihomo-γ-linolenic acid to arachidonic acid by the oil. After fractionation
of the oil with acetone into oil and non-oil fractions, it was found that the effective factor(s) was present in the non-oil
fraction. In a study on optimization of the culture conditions for the production of dihomo-γ-linolenic acid byM. alpina 1S-4, a medium containing glucose, yeast extract and the non-oil fraction was found to be suitable for the production. Under
the optimal conditions in a 50-1 fermentor, the fungus produced 107 mg of dihomo-γ-linolenic acid/g dry mycelia (2.17 g/l
of culture broth). This value accounted for 23.1% of the total fatty acids in the lipids extracted from the mycelia. The mycelia
were also rich in arachidonic acid (53.5 mg/g dry mycelia, 11.2%). Other major fatty acids in the lipids were palmitic acid
(24.1%), stearic acid (7.0), oleic acid (20.1), linoleic acid (6.6) and γ-linolenic acid (4.1).
On leave from Suntory Ltd. 相似文献
103.
Incorporation of silicon species from an alloy substrate into anodic titania is shown to stabilise the structure of the film, facilitating investigation of the ionic transport processes in amorphous titania grown at high efficiency. Thus, an amorphous anodic film developed on a sputtering-deposited Ti-6 at.%Si alloy formed to 100 V in phosphoric acid electrolyte in contrast to a partially crystalline film developed on relatively pure titanium at <20 V. Silicon species, which are immobile and act as marker species in the growing film, are present in the inner 58% of the film thickness. Evidently, the film material forms simultaneously at the film/electrolyte and alloy/film interfaces by co-operative transport of cations and anions, as is usual in amorphous anodic oxides. The phosphate anions incorporated from the electrolyte migrate inward at 0.34 times the rate of O2− ions and hence are present in the outer 62% of the film thickness. 相似文献
104.
The micro-nanoformability of Pt-based metallic glass and the nanoforming of three-dimensional structures 总被引:1,自引:0,他引:1
Yasunori Saotome Kenichi Imai Shigeo Shioda Susumu Shimizu Tao Zhang Akihisa Inoue 《Intermetallics》2002,10(11-12)
Pt48.75Pd9.75Cu19.5P22 amorphous alloy exhibits obvious glass transition behavior at a temperature of Tg=502 K, which is below the crystallization temperature Tx=588 K, and develops a supercooled liquid state in a wide temperature range of ΔTx (=Tx−Tg)=86 K. The present paper investigates the macroscopic and microscopic deformation behavior of the material and the possibility of micro-nano forming as a fabrication method and material for nano-devices. On a macroscopic scale, the material exhibits a Newtonian viscous flow in a supercooled liquid state. An index of the microformability is also evaluated by the geometrical transferability of a die shape to the material. For this study, we fabricated V-grooved micro dies of (100) Si by a silicon process. The V-groove dies are from 100 nm to 1 μm wide. The material exhibits superior formability on micrometer and nanometer scales and may possibly be applied to micro-nanomaterials for micro-nano devices. 相似文献
105.
Masao Shimizu Naoto Kudo Yoshinobu Nakajima Noboru Matsuo Yoshihisa Katsuragi Ichiro Tokimitsu Francisca Barceló 《Journal of the American Oil Chemists' Society》2008,85(7):629-633
Olive oils have a higher relative diacylglycerol (DAG) content than other plant oils. The lipase in olive fruits is involved
in DAG production and is directly related to the acidity of the olive oil. However, the lipase activity and positional selectivity
have not been clarified. To investigate the properties of olive fruit lipase, olive fruits of the Mission variety harvested
during mid-December of 2005 on Shodoshima Island (Japan) were stored at 20, 30 or 40 °C for 4 weeks. Changes in the acidity
and acylglycerol content of the oils extracted from the stored fruits were analyzed. The acidity and DAG content of the olive
oils increased due to triacylglycerol (TAG) hydrolysis during storage. sn-1,2-DAGs preferentially increased during the early stages of storage, indicating that the olive fruit lipase is enantioselective
for the sn-3 position, while non-enzymatic isomerization of sn-1,2-DAGs was observed throughout the entire duration of storage. Kinetic analysis revealed that the enantioselectivity of
olive fruit lipase for the sn-3 position was approximately four times greater than for the sn-1 position. The lipase was gradually inactivated at temperatures of 30 °C or higher, and the ratios of the rate constant
for inactivation to TAG hydrolysis at the sn-3 position was 0.2, 13, and 23 at 20, 30, and 40 °C, respectively. 相似文献
106.
The adsorption of metal ions (Mo6+, Cu2+, Fe2+, and Fe3+) was examined on chemically modified chitosans with a higher fatty acid glycidyl (CGCs), and the adsorption of Cu2+ was examined on ethylenediamine tetraacetic acid dianhydride modified CGCs (EDTA‐CGCs) synthesized by the reaction of the CGCs with ethylenediamine tetraacetic acid dianhydride. The adsorption of phosphate ions onto the resulting substrate/metal‐ion complex was measured. Mo6+ depicted remarkable adsorption toward the CGCs, although all the Mo6+ was desorbed under the adsorption conditions of the phosphate ions. The other metal ions were adsorbed to some extent on CGCs by chelating to the amino group in the substrate, except for CGC‐1, which had the highest degree of substitution (83.9%). Considerable amounts of Fe2+ were adsorbed onto CGCs; however, only a limited number of phosphate ions was adsorbed onto the substrate/metal‐ion complex. As a result, the following adsorbent/metal‐ion complexes gave higher adsorption ability toward phosphate ions: CGC‐4/Cu2+, CGC‐4/Fe3+, and EDTA‐CGC‐3/Fe3+. Where, CGC‐3 is a chemically modified chitosan with the degree of substitution of 26.5 percentage, and CGC‐4 is one with the degree of substitution of 16.0 percentage. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
107.
Kiyoyuki Shimizu Tomohito Sunagawa Keijiro Arimura Hideshi Hattori 《Catalysis Letters》1999,63(3-4):185-188
Cyclohexane isomerization to methylcyclopentane over sulfated zirconia is markedly enhanced in the presence of isopentane which acts as a hydride transfer agent to facilitate the slow step of hydride transfer from cyclohexane to isopropyl cation. This was revealed by deuterium tracer studies. This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
108.
Naoki Dohi Yukimasa Matsuda Norihiro Itano Kazuhiro Shimizu Kimio Mineka Wa Yoshinorika Wase 《加拿大化工杂志》1999,77(5):786-792
Mixing in a boil-off mechanically stirred tank reactor with multiple impellers was examined. Power consumption and gas hold-up were measured in boiling water in a 0.2 m i.d. stirred tank reactor with three four-pitched blade downflow disk turbines. Vapour was generated from both the immersed ring heater and the impellers. At low vapour generation rates, vapour was mainly generated from the impellers rather than from the heater, whereas nucleation occurred at the heater instead of the impeller at higher vapour generation rates. The mechanical power consumption decreased due to vapour generation. The change in boiling-to-non-boiling mechanical power ratio with varying impeller rotational speed and boiling rate was complicated and not monotonous except at higher impeller speeds and boiling rates. The gas hold-ups increased with increasing vapour generation rate but were rather small as compared to those in cold gas dispersing systems. Empirical correlations for power consumption and gas hold-up in boiling liquids were developed using the present experimental data. 相似文献
109.
Takeshi Watanabe Tomoko K. Shimizu Yoshitaka Tateyama Yousoo Kim Maki Kawai Yasuaki Einaga 《Diamond and Related Materials》2010,19(7-9):772-777
The physical and electrochemical properties of boron-doped polycrystalline diamond electrodes, prepared with various B/C ratio, i.e., 0.1%, 0.5% (BDD-A), 1% (BDD-B), and 5% (BDD-C), were investigated. Electrochemical measurements of the heavily boron-doped films (BDD-C) showed giant electric double-layer capacitance and activity which is significantly larger than BDD-A and BDD-B as well as glassy carbon electrodes. However, interestingly, actual boron concentration of BDD-C was observed to be almost the same as that of BDD-B by secondary ion mass spectroscopy (SIMS) and glow discharge optical emission spectroscopy (GDOES) analysis. It is suggested that the large capacitance is due to a few sp2-bonded carbon impurities, which was observed only in BDD-C, although the amount of the sp2-bonded nondiamond species are very small. In the present work, the reason for the interesting electrochemical properties of heavily boron-doped diamond electrodes is discussed. Furthermore, dimensional stability of the electrodes was also confirmed by conducting harsh anodic treatment. 相似文献
110.
Electron beam surfacing in an electron accelerator using powder mixtures of chromium carbides with boron carbide in different weight ratios and with different radiation parameters was used to produce wear- and corrosion-resisting coatings. It is shown that there are compositions of the surfacing mixtures and conditions of electron beam effect ensuring maximum values of wear and corrosion resistance. 相似文献