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31.
Kaori Bonkohara Maiko Fuji Akito Nakao Noriyuki Igura 《Bioscience, biotechnology, and biochemistry》2016,80(3):533-539
To prepare an aroma mixture of Japanese soy sauce by fewest components, the aroma concentrate of good sensory attributes was prepared by polyethylene membrane extraction, which could extract only the volatiles with diethyl ether. GC-MS-Olfactometry was done with the aroma concentrate, and 28 odor-active compounds were detected. Application of aroma extract dilution analysis to the separated fraction revealed high flavor dilution factors with respect to acetic acid, 4-hydroxy-2(or5)-ethyl-5(or2)-methyl-3(2H)-furanone (HEMF), 3-methyl-1-butanol (isoamyl alcohol), and 3-(methylsulfanyl)propanal (methional). A model aroma mixture containing above four odorants showed a good similarity with the aroma of the soy sauce itself. Consequently, the reminiscent aroma mixture of soy sauce was prepared in water. The ratio of acetic acid, HEMF, isoamyl alcohol, and methional was 2500:300:100:1. 相似文献
32.
Yamauchi J Miyamoto Y Murabe M Fujiwara Y Sanbe A Fujita Y Murase S Tanoue A 《Experimental cell research》2007,313(9):1886-1896
Valproic acid (VPA), a mood stabilizer and anticonvulsant, has a variety of neurotrophic functions; however, less is known about how VPA regulates neurite outgrowth. Here, using N1E-115 neuroblastoma cells as the model, we show that VPA upregulates Gadd45a to trigger activation of the downstream JNK cascade controlling neurite outgrowth. VPA induces the phosphorylation of c-Jun N-terminal kinase (JNK) and the substrate paxillin, while VPA induction of neurite outgrowth is inhibited by JNK inhibitors (SP600125 and the small JNK-binding peptide) or a paxillin construct harboring a Ser 178-to-Ala mutation at the JNK phosphorylation. Transfection of Gadd45a, acting through the effector MEKK4, leads to the phosphorylation of the JNK cascade. Conversely, knockdown of Gadd45a with siRNA reduces the effect of VPA. Taken together, these results suggest that upregulation of Gadd45a explains one of the mechanisms whereby VPA induces the neurotrophic effect, providing a new role of Gadd45a in neurite outgrowth. 相似文献
33.
Satake A Furukawa K Ueno T Ukeda H Sawamura M 《Bioscience, biotechnology, and biochemistry》2004,68(2):312-316
To evaluate the origin of citrus essential oils, the isotope ratio of fragment peaks on HRGC-MS of the volatile compounds from various citrus oils was measured. The MS fragment ratio was found by the ratio of fragment peak intensity, m+1/m (m/z). This ratio reflects the isotope effect of volatile compounds, that is, it provides information about locality, quality, and species for essential oils. Multivariate analysis based on the MS fragment ratio of monoterpene hydrocarbons clearly distinguished three citrus species, yuzu, lemon, and lime. The carbonyl fractions were also extracted from citrus essential oils by the sodium hydrogensulfite method. The isotope ratio of MS fragments of octanal, nonanal, and decanal was also examined. The results suggest that there was no significant difference in the individual fragment isotope ratios of the three aldehydes. 相似文献
34.
Acylated iridoid glucosides from Veronica anagallis-aquatica 总被引:1,自引:0,他引:1
Three new (1-3) and four known iridoid glucosides (4-7) as well as a known phenylethanoid glycoside (8) were isolated from the aerial parts of Veronica anagallis-aquatica and their structures were determined as 6'-O-benzoyl-8-epiloganic acid named aquaticoside A (1), 6'-O-p-hydroxybenzoyl-8-epiloganic acid named aquaticoside B (2), 6'-O-benzoyl-gardoside named aquaticoside C (3), veronicoside (4), catalposide (5), verproside (6), verminoside (7) and martynoside (8) on the basis of 1D and 2D NMR spectral analysis. 相似文献
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37.
Hamaoka T Takechi M Chinen A Nishiwaki Y Kawamura S 《Genesis (New York, N.Y. : 2000)》2002,34(3):215-220
Zebrafish retina contains five morphologically distinct classes of photoreceptors, each expressing a distinct type of opsin gene. Molecular mechanisms underlying specification of opsin expression and differentiation among the cell types are largely unknown. This is partly because mutants affected with expression of a particular class of opsin gene are difficult to find. In this study we established the transgenic lines of zebrafish carrying green fluorescent protein (GFP) gene under the 1.1-kb and 3.7-kb upstream regions of the rod-opsin gene. In transgenic fish, GFP expression initiated and proceeded in the same spatiotemporal pattern with rod-opsin gene. The retinal section from adult transgenic fish showed GFP expression throughout the rod cell layer. These results indicate that the proximal 1.1-kb region is sufficient to drive gene expression in all rod photoreceptor cells. These transgenic fish should facilitate screening of mutants affected specifically with rod-opsin expression or rod cell development by visualization of rod cells by GFP. 相似文献
38.
Sakurai H Nishi A Sato N Mizukami J Miyoshi H Sugita T 《Biochemical and biophysical research communications》2002,297(5):1277-1281
TAK1 mitogen-activated protein kinase kinase kinase (MAP3K) is activated by its specific activator, TAK1-binding protein 1 (TAB1). A constitutively active TAK1 mutant has not yet been generated due to the indispensable requirement of TAB1 for TAK1 kinase activity. In this study, we generated a novel constitutively active TAK1 by fusing its kinase domain to the minimal TAK1-activation domain of TAB1. Co-immunoprecipitation assay demonstrated that these domains interacted intra-molecularly. The TAK1-TAB1 fusion protein showed a significant MAP3K activity in vitro and activated c-Jun N-terminal kinase/p38 MAPKs and IkappaB kinase in vivo, which was followed by increased production of interleukin-6. These results indicate that the fusion protein is useful for characterizing the physiological roles of the TAK1-TAB1 complex. 相似文献
39.
Sano K Yoshikawa M Hayasaka S Satake K Ikegami Y Yoshida H Ishikawa T Sawada S Tanabe S 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,795(1):25-34
SN-38 (7-ethyl-10-hydroxycamptothecin) is an active metabolite derived from the semi-synthetic compound camptothecin (CPT) named Irinotecan (CPT-11). The antitumor activity of SN-38 is 1000-fold more potent than the parent CPT-11. Fourteen new derivatives of camptothecin have recently been developed by Yakult Honsha (Tokyo, Japan). Here we describe a simple and cost-effective high-performance liquid chromatography (HPLC) method without an ion-pairing agent, which allows the simultaneous determination of both lactone and carboxylate forms of SN-38 and other camptothecin derivatives. A weak linear relationship between the HPLC retention factors (ln k') and the cellular concentrations of these compounds was observed. These results suggest that low-polarity compounds easily accumulate in cancer cells and may circumvent drug resistance. The HPLC analysis herein described is expected to greatly assist in derivative synthesis and chemical modification of camptothecin-based antitumor drugs. 相似文献
40.
Tachykinins (TKs) constitute the largest vertebrate neuropeptide family with multifunctions in central and peripheral tissues. In several invertebrate species, two types of structurally related peptides, 'tachykinin-related peptides (TKRPs)' and 'invertebrate tachykinins (inv-TKs)' have been identified. TKRPs, isolated from the nerve and/or gut tissues, contain the common C-terminal sequence -Phe-X-Gly-Y-Arg-NH(2) (X and Y are variable) analogous to the vertebrate TK consensus -Phe-X-Gly-Leu-Met-NH(2), and exhibit vertebrate TK-like contractile activity on invertebrate gut tissues. Inv-TKs have been shown to be present exclusively in the salivary gland of several species, to share vertebrate TK consensus motif, and to possess TK-like potencies on vertebrate, not invertebrate tissues. However, the functional and evolutionary relevance of TKRPs and inv-TKs to vertebrate TKs remains to be understood. Recent studies have revealed that TKRP precursors dramatically differ from vertebrate preprotachykinins in structural organization and that TKRP receptors share structural and functional properties with vertebrate TK receptors. Moreover, the C-terminal arginine in TKRPs has been shown to play an essential role in discriminating their receptors from vertebrate TK receptors. Such recent marked progress is expected to enhance further investigation of biological roles of TKRPs. This review provides an overview of the basic findings obtained previously and a buildup of new knowledge regarding TKRPs and inv-TKs. We also compare TKRPs and inv-TKs to vertebrate TKs with regard to evolutionary relationships in structure and function among these structurally related peptides. 相似文献