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31.
Hiroko Kato Kenji Izumi Taro Saito Hisashi Ohnuki Michiko Terada Yoshiro Kawano Kayoko Nozawa-Inoue Chikara Saito Takeyasu Maeda 《Histochemistry and cell biology》2013,139(6):847-862
Aldehyde dehydrogenases (ALDHs), enzymes responsible for detoxification and retinoic acid biosynthesis, are considered a potent functional stem cell marker of normal and malignant cells in many tissues. To date, however, there are no available data on ALDH distributions and functions in oral mucosa. This study aims to clarify the levels and types of ALDH expression using immunohistochemistry with accompanying mRNA expression as well as an ALDEFLUOR assay, and to assess phenotypic and histological changes after manipulation of the ALDH activity of oral keratinocytes to increase the potency of a tissue-engineered oral mucosa by a specific ALDH inhibitor, diethylaminobenzaldehyde (DEAB), together with small interfering RNA of ALDH1A3 and ALDH3A1. Results showed the mRNA and cytoplasmic protein expression of ALDH1A3 and ALDH3A1 to be mostly localized in the upper suprabasal layer although no ALDH1A1 immunoreaction was detected throughout the epithelium. Oral keratinocytes with high ALDH activity exhibited a profile of differentiating cells. By pharmacological inhibition, the phenotypic analysis revealed the proliferating cell-population shifting to a more quiescent state compared with untreated cells. Furthermore, a well-structured epithelial layer showing a normal differentiation pattern and a decrease in Ki-67 immunopositive basal cells was developed by DEAB incubation, suggesting a slower turnover rate efficient to maintain undifferentiated cells. Histological findings of a regenerated oral epithelium by ALDH1A3 siRNA were similar to those when treated with DEAB while ALDH3A1 siRNA eradicated the epithelial regenerative capacity. These observations suggest the effects of phenotypic and morphological alterations by DEAB on oral keratinocytes are mainly consequent to the inhibition of ALDH1A3 activity. 相似文献
32.
Tei Yamanishi Michiko Kosuge Yukiko Tokitomo Ryoko Maeda 《Bioscience, biotechnology, and biochemistry》2013,77(9):2139-2142
The aroma constituents of the highest quality pouchong tea were characterized by GC–MS. Forty-eight components, including five newly identified compounds were characterized. GC peak area percentages of the main components in pouchong tea were compared with those of jasmine tea to differentiate compounds contributing to the aroma characteristics of pouchong tea with superior floral elegant flavor. Nerolidol, jasmine lactone, methyl jasmonate, indole, benzyl cyanide and linalool oxides were found in much higher concentration in pouchong tea than in jasmine tea. These compounds seemed to contribute to the aroma characteristics of the highest quality pouchong tea. 相似文献
33.
Soichi Arai Michiko Yamashita Masao Fujimaki 《Bioscience, biotechnology, and biochemistry》2013,77(7):1253-1256
AK-toxin I, a host-specific toxin to Japanese pear (Pyrus serotina), was synthesized as its methyl ester from three precursor fragments: conjugated diene-carboxylic acid, chiral epoxyalcohol and β-methylphenylalanine. The epoxyalcohol fragment was derived from D-fructose, in which effective homologation of the hemiacetal carbon to alkyne by using dimethyl 1-diazo-2-oxopropylphosphonate was the key reaction. The diene-carboxylic acid fragment was prepared by repeated Wittig reactions, and was combined with the epoxyalcohol fragment by the Stille reaction. Esterification of the combined product with the stereochemically-pure β-methylphenylalanine fragment afforded the target compound. This method was used to prepare the methyl ester of tritium-labeled AK-toxin I with a specific radioactivity of 213 GBq/mmol. 相似文献
34.
Satoshi Ōmura Michiko Katagiri Juichi Awaya Kiyoo Atsumi Ruiko Ōiwa Toju Hata 《Bioscience, biotechnology, and biochemistry》2013,77(12):2805-2812
A newly described species of Streptomyces (named Sm. kagawaensis ATCC No. 21811) isolated from soil was found to produce a new antifungal antibiotic, prumycin, which belongs to amino sugar group. Prumycin was isolated from the fermentation broth by ion-exchange adsorption and gel-filtration methods. This antibiotic inhibited specifically the growth of Sclerotinia sp. and Botrytis sp. on flower pot test with kidney bean leaves and also was effective on the field test with various plants. 相似文献
35.
Michiko Nose Yoichi Nakatani Tei Yamanishi 《Bioscience, biotechnology, and biochemistry》2013,77(2):261-271
By continuing flavor analysis of green tea from a previous paper, further twenty seven compounds were newly identified. These compounds are limonene, α-cubebene, α-copaene, caryophyllene, α-humulene, α- and γ-muurolene, β-sesquiphellandrene, δ-cadinene, calamenene, cubenol, α-cadinol, α-terpineol, n-heptanol, n-nonanol, furfurylalcohol, n-nonanal, N-ethylformylpyrrole, pyrrylmethylketone, 6-methyl-trans-3,5-heptadien-2-one, 2′,2″-dihydro-α-ionone, 6,10,14-trimethyl-2-pentadecanone, cis-3-hexenylcaproate, cis-3-hexenylbenzoate, α-terpinylacetate, coumarin and diphenylamine.Relative quantities of known compounds in intermediate- and high-boiling fraction were determined. 相似文献
36.
Soichi Arai Makoto Abe Michiko Yamashita Hiromichi Kato Masao Fujimaki 《Bioscience, biotechnology, and biochemistry》2013,77(4):552-559
An indole derivative having blue fluorescence was produced in cooked soybean digested at 37°C for 24 hr with an acid proteinase Molsin (optimum pH: 2.8) from Aspergillus saitoi or a usual acid proteinase pepsin (optimum pH: 1.6) from beef stomach. This indole derivative was identical with a condensation product from l-tryptophan and n-hexanal. Based on MS, NMR, IR and UV spectrometry, the condensation product was identified as l-pentyl-2, 3, 4, 9-tetrahydro-lH-pyrido [3, 4-b]-indole-3-carboxylic acid [trivial name: 1-pentyl-l, 2, 3, 4-tetrahydro-2-carboline carboxylic acid-(3)].Data were presented of the formation of the above indole derivative and of the resulting consumption of l-tryptophan and n-hexanal.The possible ocurrence of the formation of Harmala alkaloids, i.e. 2-carboline derivatives, through in vitro digestion of soybean with acid proteinases was discussed.A carbonyl-trapping ability of l-tryptophan was suggested. 相似文献
37.
Shinsuke Fujihara Masuro Yamaguchi 《Bioscience, biotechnology, and biochemistry》2013,77(11):2569-2573
The activity of nitrogenase and the concentration of ammonia and allantoin (+ allantoic acid) in root nodules were measured throughout the growth period of soybean plants. Nitrogenase activity measured by acetylene reduction increased with plant growth and reached a maximum level at the flowering period. The level of ammonia and allantoin concentration in nodules was parallel with increased nitrogenase activity. At the late reproductive stage (pod-forming period), nitrogenase activity showed a marked decrease, but the ammonia and allantoin in the nodules remained at a constant level. Detached nodules from 56 day-old soybean plants were exposed to 15N2 gas, and the distribution of 15N among nitrogen compounds was investigated. Enrichment of 15N in allantoin and allantoic acid reached a fairly high level after 90 min of nitrogen fixation; ca. 22% of 15N in acid-soluble nitrogen compounds was incorporated into allantoin + allantoic acid. In contrast, enrichment of 15N in amide nitrogen was relatively low. No significant 15N was detected in the RNA fraction. The data suggested that ureide formation in nitrogen-fixing root nodules did not take place through the breakdown of nucleic acids, but directly associated with the assimilating system of biologically fixed nitrogen. 相似文献
38.
Soichi Arai Masatoshi Noguchi Michiko Yamashita Hiromichi Kato Masao Fujimaki 《Bioscience, biotechnology, and biochemistry》2013,77(9):1338-1345
Soy proteins were incubated with a microbial acid protease (Molsin) under the following condition: substrate concentration, 1%; enzyme-substrate ratio (by weight), 1/100; pH, 2.8; and temperature, 40°C—flavor components and related impurities are removable from crude soy-protein concentrates by their incubation for 2 hr under the above condition. The acid-precipitated fraction of soy protein incubated for 2 hr with Molsin (i.e. 2 hr-proteolyzate) showed the following composition: 10% trichloroacetic acid (TCA) insoluble fraction, 47.52%; 10% TCA soluble peptide fraction, 52.02%; and free amino acid fraction, 0.46%. Gel filtration of the 2 hr-proteolyzate gave an elution pattern showing its molecular weight distribution.In the process of the incubation of the acid-precipitated protein, the 10% TCA insoluble fraction showed increase in amino nitrogen content, its solubility in a phosphate buffer increased to change at 6 hr, and a hydrophobic amino acid share in this fraction increased gradually.In vitro digestibility of the acid-precipitated fraction were improved and the lipoxygenase activity in this fraction decreased through the Molsin treatment.Ultracentrifugal analysis showed a decreasing tendency of the cold-insoluble fraction of soy protein during its incubation with Molsin. Optical rotatory dispersion and circular dichroism study elucidated conformational changes in this fraction during its incubation either with or without Molsin. 相似文献
39.
Michiko Yamashita Soichi Arai Shin-ya Tanimoto Masao Fujimaki 《Bioscience, biotechnology, and biochemistry》2013,77(4):953-954
An investigation was conducted on myosin and actin-activated heavy meromyosin (HMM) ATPase activities in normal porcine muscle stored for varying periods of time after death. Studies were also made on temperature dependent myosin ATPase, initial burst of ATPase and actin-activated HMM ATPase in normal and in pale, soft and exudative (PSE) porcine muscle. The maximum velocity of acto-HMM ATPase of normal muscle decreased considerably with postmortem time, while the apparent dissociation constant decreased slightly. The maximum velocity of acto-HMM ATPase of postmortem normal muscle was approximately two-times larger than that of the corresponding PSE muscle. However, almost no difference was found in the apparent dissociation constant. The size of the initial burst of phosphate-liberation of myosin prepared from normal muscle was approximately 1.2 mol/mol of myosin and from PSE muscle 0. It is assumed that the lack of contractility of PSE muscle was brought about by two basic myosin malfunctions: one, the irreversible binding of myosin to actin filament and the other, the functional damage of myosin ATPase, responsible for the formation of phosphorylated complex, even when dissociable. 相似文献
40.
Hiroki Murakami Toshihiro Miyoshi Michiko Koga Koji Yamada Hirohisa Omura 《Bioscience, biotechnology, and biochemistry》2013,77(4):795-801
Strand breakages of mammalian cellular chromosomal DNA with aromatic reductones were ascertained by use of a cultured cell strain of the rat fetal lung (RFL). The mode of the breakages was investigated by ultracentrifugal analyses. The reductones induced the breakages of the cellular DNA in two different fashions; one is single strand breaks and another double strand breaks. Although the single strand breaks were rapidly repaired, double strand breaks were only partially repaired. Both breaks were not cytocidal. Some physiological alterations were observed to follow the strand breaks. 相似文献