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101.
Antimicrobial activity of nutmeg against Escherichia coli O157 总被引:2,自引:0,他引:2
Takikawa A Abe K Yamamoto M Ishimaru S Yasui M Okubo Y Yokoigawa K 《Journal of Bioscience and Bioengineering》2002,94(4):315-320
We examined the difference between Escherichia coli O157 and non-pathogenic E. coli in their tolerance to spices. Various spices (5 g each) were homogenized at 25 degrees C for 10 min with 5 ml of 70% ethyl alcohol, and the supernatant solutions obtained by centrifugation were used as spice extracts. When the E. coli strains were incubated with each spice extract at concentrations of 0.01% and 0.1%, a noteworthy difference was observed between the O157 and non-pathogenic strains in their tolerance to nutmeg. The populations of the non-pathogenic strains could not be reduced, but those of the O157 strains were remarkably reduced. Antibacterial activity by the nutmeg extract was also found against the enteropathogenic E. coli O111, but not against enterotoxigenic (O6 and O148) and enteroinvasive (O29 and O124) E. coli. When we examined the antibacterial effect of volatile oils in nutmeg on the O157 and non-pathogenic E. coli strains, all O157 strains tested were found to be more sensitive to beta-pinene than non-pathogenic E. coli strains. 相似文献
102.
Kami D Takeda S Itakura Y Gojo S Watanabe M Toyoda M 《International journal of molecular sciences》2011,12(6):3705-3722
Nanoparticle technology is being incorporated into many areas of molecular science and biomedicine. Because nanoparticles are small enough to enter almost all areas of the body, including the circulatory system and cells, they have been and continue to be exploited for basic biomedical research as well as clinical diagnostic and therapeutic applications. For example, nanoparticles hold great promise for enabling gene therapy to reach its full potential by facilitating targeted delivery of DNA into tissues and cells. Substantial progress has been made in binding DNA to nanoparticles and controlling the behavior of these complexes. In this article, we review research on binding DNAs to nanoparticles as well as our latest study on non-viral gene delivery using polyethylenimine-coated magnetic nanoparticles. 相似文献
103.
The solvent extraction of picric acid(Hpic) from acid aqueous chloride solutions into cyclohexane with trioctylphosphine oxide(TOPO) and trioctylamine(TOA) was examined and the UV-visible spectrum of the organic phase was studied. In the organic phase, the acid associates with one or two TOPO molecules but it associates with only one TOA molecule. The absorption peak of the 1:1 associate with TOPO appears only in the UV range and thus it is assumed to be a hydrogen-bonded molecular adduct. The 1:2 associate with TOPO and the 1:1 associate with TOA, on the other hand, has a marked absorption peak in the visible range which is quite similar to that of picrate ions and thus the extracts are assumed to be ion pairs in which an electron transfers from the hydrogen atom to the oxygen atom in the OH-group. For this reason, the spectrum of TOPO extract is dependent on the amount of free extractant but that of TOA extract is not. 相似文献
104.
Abstract The Boleo leach solution contains large amounts of manganese (45 g/L), magnesium (25 g/L) and small amounts of cobalt (0.2 g/L) and zinc (1 g/L) in sea water. Due to the high manganese concentration, it is very difficult to separate cobalt and zinc from manganese, magnesium, and calcium using conventional solvent-extraction processes, which has led to the development of a synergistic solvent extraction (SSX) system consisting of Versatic 10 and LIX®63. By adding 0.4 M LIX 63 to 0.5 M Versatic 10, large synergistic shifts were obtained for cobalt (max. ΔpH50 4.24) and zinc (max. ΔpH50 1.62). After a single contact at pH 4.5, the extraction of cobalt was almost complete and that of zinc 80%. The extraction of manganese was 1.55%, and almost no magnesium and calcium were extracted, indicating excellent separation of cobalt and good separation of zinc from manganese, magnesium, and calcium. The SSX system was further optimized to reduce the co-extraction of manganese with the synthetic Boleo demonstration plant solution. It was found that with 0.33 M Versatic 10 and 0.30 M LIX 63, the SSX system composition approached optimum. After a single contact at pH 5.5, the extractions of cobalt and zinc were 93% and 70%, respectively, while the manganese concentration in the loaded organic solution was only 0.28 g/L. The extraction and stripping kinetics of cobalt and zinc were rapid. The SSX system was tested in two integrated pilot-plant trials with excellent results. Baja Mining has planned to implement the SSX circuit in their future Boleo plant. 相似文献
105.
Takashi Ide Ayana Azechi Natsuko Suzuki Yoko Kunimatsu Chihiro Nakajima Sayaka Kitade 《Journal of Functional Foods》2013,5(1):71-79
Effects of dietary α-lipoic acid enantiomers on hepatic and serum lipid concentrations and the activity and mRNA levels of enzymes involved in hepatic fatty acid metabolism were examined in rats. Rats were fed experimental diets containing 0 or 2.5 g/kg of α-lipoic acid enantiomers (a racemic mixture of R/S-, S- or R-α-lipoic acid) for 21 days. Various α-lipoic acid preparations decreased serum and liver concentrations of triacylglycerol, and also lowered serum concentrations of cholesterol and phospholipid and the concentration of cholesterol in the liver. α-Lipoic acid decreased the activity and mRNA levels of various hepatic lipogenic enzymes and also decreased the activities of carnitine acyltransferase and 3-ketoacyl-CoA thiolase and mRNA levels of carnitine palmitoyltransferase 1a involved in fatty acid oxidation in the liver; however, R- and S-enantiomers of α-lipoic acid as well as well as a racemic mixture of R/S-α-lipoic acid were indistinguishable in altering these indices for lipid metabolism. 相似文献
106.
Fengjuan Li Mayumi Ohnishi-Kameyama Yoko Takahashi Kohji Yamaki 《Journal of Functional Foods》2013,5(4):1991-1995
Angiotensin I-converting enzyme (ACE) inhibitory activities of aqueous extracts of Chinese commercial soypaste were investigated in this work. Six samples from northern China showed potent ACE inhibitory activities with IC50 values less than 40.0 μg/mL. ACE inhibitors in the sample with the strongest activity were purified by ultrafiltration, solid-phase extraction and gradient RP-HPLC. According to spectroscopic methods, a compound (M328.1) was separated as C15H21NO7. It was supposed to be a conjugate of phenylalanine and glucose generated by Maillard reaction during soypaste production, providing support on the contribution of Maillard reaction products to the ACE inhibitory activity of the sample. Results further indicated that the total ACE inhibition by the sample occurred from the combined function of various bioactive substances, suggesting that Chinese soypaste could be a good source of ACE inhibitors for exploring functional foods or ingredients with antihypertensive effect. 相似文献
107.
Shinichi Sakida Satoshi Hayakawa Toshinobu Yoko 《Journal of the American Ceramic Society》2001,84(4):836-842
The structures of M2 O3 –TeO2 (M = Al and Ga) glasses have been investigated by means of 125 Te, 27 Al, and 71 Ga NMR spectroscopies. The structural units of respective cations in M2 O3 –TeO2 glasses were quantitatively analyzed. The fractions of TeO4 trigonal bipyramid, AlO6 and GaO6 octahedra decreased and those of TeO3 trigonal pyramid, AlO4 , AlO5 , and GaO4 polyhedra increased with increasing M2 O3 content. Based on the local structures around Te, Al, and Ga atoms, the structure models of M2 O3 –TeO2 glasses were proposed. 相似文献
108.
In the weak magnetic field perpendicular to the discharge electric field, both the electrons and positive ions are transported in the direction of E×B drift by the space charge electric field produced by the preceded electrons. As a result, radicals are generated uniformly outside of discharge space between the electrodes in the direction of E×B drift. On the other hand, negatively charged heavy particles such as dust particles can be removed from discharge space in the direction opposite to E×B drift of plasmas. The authors have studied the transport mechanisms of magnetized dusty plasmas and its applications for the large-area uniform a-Si:H thin film deposition in plasma CVD methods. This paper reviews the transport phenomena and the transport mechanisms of dust particles and the results of film preparation under particle-free process conditions. 相似文献
109.
Tomoko Okuyama Jun Shirakawa Kazuki Tajima Yoko Ino Heidrun Vethe Yu Togashi Mayu Kyohara Ryota Inoue Daisuke Miyashita Jinghe Li Nozomi Goto Taiga Ichikawa Shingo Yamasaki Haruka Ohnuma Rie Takayanagi Yayoi Kimura Hisashi Hirano Yasuo Terauchi 《International journal of molecular sciences》2020,21(21)
110.