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101.
The time-dependent velocity field in a rotating Couette system has been decomposed. Successive instantaneous velocity profiles were obtained by an ultrasonic Doppler velocity profile method, and the spatiotemporal velocity field had been analyzed by two-dimensional Fourier transform. The Fourier spectrum is depicted by intrinsic peaks, and the velocity field cpan be reconstructed with these peak components only, indicating a successful decomposition of the velocity field. This method shows that the so-called broadband component, which is purely spatiotemporal and attributed to chaos, corresponds to a global motion of the wave propagating from roll to roll. 相似文献
102.
Majekodunmi O Fatope Suad Khamis S Al Burtomani Yoshio Takeda 《Journal of agricultural and food chemistry》2002,50(2):357-360
The seeds of Punica granatum, known as hap roman in the Arabian Peninsula, are commonly eaten as a dessert. As part of an ongoing project to find nonnutritional natural products which have health benefits, or that can be exploited to protect crops, the chloroform-soluble extract of the fermented seeds of P. granatum was found to be rich in 1-O-trans,cis,trans-9,11,13-octadecatrienoyl glycerol (1). The seed oil is not lethal to brine shrimp larvae. 1-O-isopentyl-3-O-octadec-2-enoyl glycerol (2) and the known cis-9-octadecenoic, octadecanoic, and eicosanoic acids were also detected in small amounts in the seed oil by LC and MS. The structure of 1 was determined from NMR and MS spectral data. 相似文献
103.
Antioxidant mechanism of carnosic acid: structural identification of two oxidation products. 总被引:1,自引:0,他引:1
To determine the antioxidant mechanism of food phenolics against the oxidation of food components, the reaction of carnosic acid, an antioxidative constituent of the popular herbs sage and rosemary, was investigated in the presence of ethyl linoleate and the radical oxidation initiator 2,2'-azobis(2,4-dimethylvaleronitrile). During this process, carnosic acid was oxidized to an o-quinone and a hydroxy p-quinone, the chemical structures of which were confirmed by physical and chemical techniques. From a quantitative time course analysis of the production of these quinones, an antioxidant mechanism of carnosic acid is proposed, consisting of the oxidative coupling reaction with the peroxyl radical at the 12- or 14-position of carnosic acid and subsequent degradation reactions. 相似文献
104.
Masuda T Inaba Y Maekawa T Takeda Y Tamura H Yamaguchi H 《Journal of agricultural and food chemistry》2002,50(21):5863-5869
A solution of carnosic acid quinone, which is a radical chain-termination product having no antioxidant activity in the antioxidant reaction of carnosic acid, recovers potent antioxidant activity upon standing. The HPLC analysis of an aged solution of carnosic acid quinone revealed that several antioxidants are produced in the solution. From the time-course and quantitative analyses of the formation of the products and their structural analysis, an antioxidant mechanism from carnosic acid quinone is proposed that includes a redox reaction of carnosic acid quinone in addition to the isomerization to lactone derivatives. In the first stage of antioxidation, carnosic acid, the reduction product from carnosic acid quinone, contributes to the potent antioxidant activity of the solution. This proposed mechanism can explain one of the reasons for the strong antioxidant activity of the extract of the popular herbs sage and rosemary. 相似文献
105.
The volatile fatty acids produced by the representative strains of clostridia isolated from paddy field soil were surveyed. All the strains, except Cl. tertium, utilized only amino acids as the sole source of energy for growth. All of them produced acetic and butyric acids, and some of them produced propionic acid in addition. Iso-valeric and iso-butyric acids were also produced, except by Cl. tertium. These results suggest that all the strains, except Cl. tertium, may carry out the STICKLAND reaction. The cells of each strain harvested from the culture in the VL medium were subjected to examination whether or not they carried out the STICKLAND reaction in the presence of leucine or glycine. All the strains, except Cl. tertium, catalyzed the STICKLAND reaction and some strains also metabolized leucine and glycine even when they were supplied singly. 相似文献
106.
Yoshiyuki Takeda 《茶叶》2013,(4):201-204
Tea breeding in Japan started around 116 years ago,and to date,more than 110 cultivars have been developed and released.Seedling plants were uprooted and rapidly replaced with new clonal cultivars after 1970.At present,more than 95% of the tea gardens in Japan grow improved clonal cultivars.Although the cultivation of the "Yabukita" variety had expanded and contributed to approximately 76% of the tea grown,this excessive plantation resulted in some serious problems in the cultivation and management of the tea industry after 1990.Therefore,after 2000,new programs have been initiated to breed superior varieties through the use of various genetic resources and DNA markers. 相似文献
107.
Keiji Okada Itaru Sato Yoshitaka Deguchi Shigeru Morita Takeshi Yasue Masato Yayota Ken‐ichi Takeda Shusuke Sato 《Animal Science Journal》2013,84(12):798-801
After the disastrous incident of the Fukushima Daiichi Nuclear Power Station, various agricultural, livestock and fishery products have been inspected for radioactive contamination with cesium in Japan. In this study, radioactive cesium was measured in various edible parts of cattle to verify the current inspection method for cattle, in which the neck tissues are generally used as samples. Radioactive cesium concentration in the short plate, diaphragm, liver, lung, omasum, abomasum and small intestine were lower and sirloin, tenderloin, top round meat and tongue were higher than that in the neck. There was no significant difference between the other organs (heart, kidney, lumen and reticulum) and the neck. Ninety‐five percent upper tolerance limits of the relative concentration to the neck were 1.88 for sirloin, 1.74 for tenderloin, 1.87 for top round and 1.45 for tongue. These results suggest that a safety factor of 2 is recommended for the radioactivity inspection of cattle to prevent a marketing of meat with higher cesium than the legal limit. Re‐inspection should be conducted using another part of muscle, for example, top round, when suspicious levels of 50–100 Bq/kg are detected in the neck. 相似文献
108.
Francis Wachira Junichi Tanaka Yoshiyuki Takeda 《The Journal of Horticultural Science and Biotechnology》2013,88(5):557-563
SummaryGenetic variation and resulting variable groupings in tea (Camellia sinensis) and its wild Camelia relatives were assessed using Random Amplified Polymorphic DNA (RAPD) and Amplified Fragment Length Polymorphic (AFLP) markers. Numerous polymorphic bands were generated, of which 266 unambiguous ones were scored. The highest level of polymorphism as determined by the expected heterozygosity (Hav) was detected with AFLPs. Three major groups were recognized in the germplasm based on the parsimony method of cluster analysis. Two of the groups corresponded to varieties assamica and sinensis while the third group consisted of a heterogeneous mix of tea cultivars and related wild species. The Taiwan yamacha, unique tea cultivars grown predominantly in the highlands of Taiwan for the production of pan fired semi-fermented (Oolong and Pouchong) tea clustered in this group. Analysis of phenotypic diversity based on the generated RAPD and AFLP profiles revealed that population diversity (H), decreased in the order; Wild Camellia >India > China > Kenya > Sri-lanka > Vietnam > Japan > Taiwan. Analysis of molecular variance (AMOVA) revealed that most variation resided among individuals within populations (72%). Calculation of genetic distances and nested AMOVA further revealed a significant degree of structuring among the populations based on the country of origin. 相似文献
109.
Isolation and characterization of a phenolic antioxidant from the Pacific oyster (Crassostrea gigas)
Watanabe M Fuda H Jin S Sakurai T Ohkawa F Hui SP Takeda S Watanabe T Koike T Chiba H 《Journal of agricultural and food chemistry》2012,60(3):830-835
Using an oxygen radical absorbance capacity (ORAC) assay, antioxidant activity was detected in the ethanol extract of the Pacific oyster, which was purified by sequential extraction with organic solvents. The ethyl acetate fraction showed the strongest antioxidant activity and was further purified, yielding a single compound [as assessed by thin-layer chromatography (TLC) and reverse-phase high-performance liquid chromatography (HPLC)]. This compound was identified as 3,5-dihydroxy-4-methoxybenzyl alcohol on the basis of (1)H and (13)C nuclear magnetic resonance (NMR), heteronuclear multiple-bond correlation (HMBC), and electrospray ionization-mass spectrometry (ESI-MS) spectral analyses, a conclusion that was confirmed by chemical synthesis. The concentration of the compound was 6.7 mg/100 g of whole oyster meat wet weight. This amphiphilic antioxidant retarded the copper-mediated oxidation of low-density lipoproteins (LDLs) and the generation of thiobarbituric acid reactive substances. Furthermore, the compound showed substantial antioxidant activity using the ORAC and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays compared to natural antioxidants. Although the same compound was previously found in brown algae, its presence in other organisms and antioxidant activity are reported here for the first time. 相似文献
110.
Naoya Urasaki Shinji Kawano Hiroyuki Mukai Takashi Uemori Osamu Takeda Teruo Sano 《Journal of General Plant Pathology》2008,74(2):151-155
We developed a detection method for “Candidatus Liberibacter asiaticus”, causal agent of citrus huanglongbing, using isothermal and chimeric primer-initiated amplification
of nucleic acids combined with cycling probe technology (Cycleave ICAN). With Cycleave ICAN, the reaction was done in one
tube in 1 h without the need for electrophoresis, and false positives were not generated. In addition, Cycleave ICAN method
was more sensitive than the conventional PCR method. Cycleave ICAN helps shorten the time for the large-scale detection needed
to manage huanglongbing. 相似文献