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71.
Abayomi P. Adebiyi Ayobamitale O. Adebiyi Tomohisa Ogawa & Koji Muramoto 《International Journal of Food Science & Technology》2008,43(1):35-43
Crude rice bran protein (CRBP) was prepared by alkaline extraction and then treated with 0.6 m HCl to remove phytic acid. The phytate‐free rice bran protein (PFRBP) was hydrolysed with proteases M, N, S, P and pepsin under optimal conditions. Hydrolysates obtained from various hydrolysis periods were subjected to analysis for their degree of hydrolysis (DH) and functional properties. The hydrolysates were fractionated by reversed‐phase column chromatography on Kaseigel ODS resin (120–140 μm) using a stepwise gradient of aqueous ethanol, and their activities were measured. The 40% ethanol fraction of protease P 4 h‐hydrolysate was separated by successive reversed‐phase high‐performance liquid chromatography and the amino acid sequences of isolated antioxidative peptides were determined by a protein sequencer and matrix‐assisted laser desorption ionisation‐time of flight mass spectrometry. Crude rice bran protein had higher antioxidative activity than PFRBP, due to the presence of phytic acid. Phytate contents of rice bran, CRBP and PFRBP were 2.5%, 1.42% and 0%, respectively. The activity of PFRBP increased upon protease digestion. Protease M hydrolysates showed the highest DH, but the lowest antioxidative activity. Hydrolysates with DH below 10% had higher antioxidative activity than those above 20%. This result indicates that the antioxidative activity of the hydrolysates is inherent to their characteristics amino acid sequences of peptides depending on the protease specificities. 相似文献
72.
Heat-moisture treatment of high-amylose corn starch increases dietary fiber content and lowers plasma cholesterol in ovariectomized rats 总被引:1,自引:0,他引:1
ABSTRACT: The effect of dietary high-amylose corn starch (HACS) of varying dietary fiber (DF) content on plasma cholesterol was examined in ovariectomized (OVX) rats. Gelatinized normal corn starch (G-CS) was used as a reference. OVX rats were fed a fiber-free purified diet containing G-CS, HACS, gelatinized high-amylose corn starch (G-HACS), or heat-moisture treated HACS (HM-HACS) at 400 g starch/kg diet for 21 d. The DF content of G-CS, HACS, G-HACS, and HM-HACS measured by the AOAC method was 0.1, 19.3, 2.4, and 64.5 g/100 g, respectively. The dry weight of cecal contents, cecal wall weight, the amount of short chain fatty acids in cecal contents, the amount of bile acids in small intestinal contents, and fecal excretion of neutral sterols increased logarithmically with increasing DF, while total plasma cholesterol concentration decreased. On the other hand, hepatic CYP7A1 activity, fecal dry weight, and fecal excretion of bile acids increased linearly with increasing DF, while body weight gain decreased. The hypocholesterolemic effect of HACS in OVX-rats appeared to be more effective by heat-moisture treatment. 相似文献
73.
Regiospecific analysis by ethanolysis of oil with immobilized <Emphasis Type="Italic">Candida antarctica</Emphasis> lipase 总被引:1,自引:1,他引:1
Shimada Y Ogawa J Watanabe Y Nagao T Kawashima A Kobayashi T Shimizu S 《Lipids》2003,38(12):1281-1286
A mixture of oil/ethanol (1∶3, w/w) was shaken at 30°C with 4% immobilized Candida antarctica lipase by weight of the reaction mixture. The reaction regiospecifically converted FA at the 1- and 3-positions to FA ethyl
esters, and the lipase acted on C14−C24 FA to a similar degree. The content of 2-MAG reached a maximum after 4 h; the content was 28–29 mol% based on the total amount
of FA in the reaction mixture at 59–69% ethanolysis. Only 2-MAG were present in the reaction mixture during the first 4 h,
and 1(3)-MAG were detected after 7 h. After removal of ethanol from the 4-h reaction mixture by evaporation, 2-MAG were fractionated
by silica gel column chromatography. The contents of FA in the 2-MAG obtained by ethanolysis of several oils coincided well
with FA compositions at the 2-position, which was analyzed by Grignard degradation. It was shown that ethanolysis of oil with
C. antarctica lipase can be applied to analysis of FA composition at the 2-position in TAG. 相似文献
74.
Explosion sensitivity involves many complex factors. A theory for evaluating and a method for testing have to be established. We have proposed an explosion sensitivity theory for explosive substances and have also tested the evaluating method. The results of our research reveal a satisfactory mutual relation between both theoretical and experimental values. 相似文献
75.
Yasutaka Miyachi Takashi Miyazawa Yoshihiro Ogawa 《International journal of molecular sciences》2022,23(6)
Understanding the genetic factors of diabetes is essential for addressing the global increase in type 2 diabetes. HNF1A mutations cause a monogenic form of diabetes called maturity-onset diabetes of the young (MODY), and HNF1A single-nucleotide polymorphisms are associated with the development of type 2 diabetes. Numerous studies have been conducted, mainly using genetically modified mice, to explore the molecular basis for the development of diabetes caused by HNF1A mutations, and to reveal the roles of HNF1A in multiple organs, including insulin secretion from pancreatic beta cells, lipid metabolism and protein synthesis in the liver, and urinary glucose reabsorption in the kidneys. Recent studies using human stem cells that mimic MODY have provided new insights into beta cell dysfunction. In this article, we discuss the involvement of HNF1A in beta cell dysfunction by reviewing previous studies using genetically modified mice and recent findings in human stem cell-derived beta cells. 相似文献
76.
In this paper, we present a self-consistent and 3D quantum simulator for Si-nanowire transistors based on the Wigner function model and multidimensional Schrodinger-Poisson algorithm. To achieve a sufficient numerical accuracy for calculating subthreshold current, we introduced a third-order differencing scheme for discretizing the drift term in the Wigner transport equation. By comparing with semiclassical Boltzmann and nonequilibrium Green's function approaches, the validity of the present simulator is confirmed. We also demonstrate that the source-drain tunneling is a critical physical phenomenon related to a scaling limit of nanowire devices, and the semiclassical simulation measurably underestimates a minimum gate length. 相似文献
77.
Kiyoharu Nakagawa Hirokazu Oda Akira Yamashita Masahiro Okamoto Yoichi Sato Hidenori Gamo Mikka Nishitani-Gamo Kazuyuki Ogawa Toshihiro Ando 《Journal of Materials Science》2009,44(1):221-226
We developed a novel spherical carbon material. The spherical carbon is composed of a high density of carbon nanotubes or
nanofilaments, and includes an oxidized diamond particle as a core. Syntheses of this carbon in high volume with high selectivity
may be possible. It is expected that this carbon will be useful as a catalyst material for fuel cells, electric double-layer
capacitors, etc. 相似文献
78.
79.
Kazuya Ogawa Naoyuki Makiuchi Yoshiaki Kobuke 《International journal of molecular sciences》2013,14(1):322-331
A conjugated-bisimidazolylporphyrin bridged by bis(ethynylfluorene) was synthesized and organized into linear polymer through self-coordination having mean molecular weights, Mw and Mn, of ~2.1 × 105 Da and ~1.6 × 105 Da, respectively. A large two-photon absorption cross section value of 3.4 × 105 GM (per dimer unit) was observed. This value was comparable to that of the previously reported self-assembled linear polymer consisting of butadiyne-bridged imidazolylporphyrins. The two-photon absorption properties could be controlled by tuning the wavelength and absorption intensity of the one-photon absorption. 相似文献
80.