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141.
Heat processing is responsible for the change in the flavor of a coffee drink. In this study, the application of gas chromatography-olfactometry of headspace samples (GCO-H) using the vapor fraction before and after heat processing of the coffee samples resulted in the detection of 12 odor-active peaks for which the flavor dilution (FD) factors changed. Eight potent odorants were identified from these peaks by gas chromatography-mass spectrometry (GC-MS). Among these components, methanethiol (putrid), acetic acid (sour), 3-methylbutanoic acid (sour), 2-furfuryl methyl disulfide (meaty), and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (caramel-like) increased after heating of the coffee sample, whereas 2-furfurylthiol (roasty), methional (potato-like), and 3-mercapto-3-methylbutyl formate (roasty) decreased compared with the coffee sample before heat treatment. In addition, extensive studies have been carried out on the pH effects on the change in the concentration of 2-furfurylthiol during heat processing and in the pH range of 5-7; it was found that the concentration of this compound in the model solutions had significantly changed. 相似文献
142.
Journal of General Plant Pathology - 相似文献
143.
Natsumi ENDO Kiyosuke NAGAI Tomomi TANAKA Hideo KAMOMAE 《The Journal of reproduction and development》2013,59(3):282-287
The aim of this study was to examine whether increased frequency of luteinizing hormone
(LH) pulses influences luteal progesterone (P4) secretion by measuring
progesterone concentrations at the secreted (caudal vena cava) and circulating levels
(jugular vein) in lactating dairy cows. Cows received six intravenous administrations of
2.5 μg of GnRH (gonadorelin acetate, n=4) or 2 ml saline (n=3) at 1-h intervals on 12.4 ±
0.4 (mean ± SE) days after ovulation. Blood samples were collected from the caudal vena
cava and jugular vein every 12 min for 12 h (6 h before and after treatment). During the 6
h after treatment, frequency of LH pulses (5.3 ± 0.3 and 3.0 ± 0.0 pulses/6 h) and mean LH
concentration (0.50 ± 0.06 and 0.38 ± 0.05 ng/ml) were greater (P<0.05) in GnRH-treated
cows than in saline-treated cows. Mean P4 concentration and amplitude of
P4 pulses in the caudal vena cava during the 6 h after treatment were greater
(P<0.05) in GnRH-treated cows than in saline-treated cows, but the frequency of
P4 pulses was not different between the groups. Mean P4
concentration in the jugular vein during the 6 h after treatment was also higher
(P<0.05) in GnRH-treated cows than in saline-treated cows (7.0 ± 1.3 and 5.4 ± 0.9
ng/ml). These results indicate that the increased frequency of LH pulses stimulates
progesterone secretion from the functional corpus luteum and brings about higher
P4 concentrations in the circulating blood in lactating dairy cows. 相似文献
144.
145.
Natsumi ENDO Kiyosuke NAGAI Tomomi TANAKA Hideo KAMOMAE 《The Journal of reproduction and development》2013,59(2):107-114
The present study was designed to assess progesterone profiles at the secreted (caudal
vena cava) and circulating levels (jugular vein) and luteinizing hormone (LH) secretion
pattern in lactating and non-lactating cows with reference to feeding. Four lactating and
four non-lactating cycling Holstein cows were examined. Blood samples were collected
simultaneously from the caudal vena cava (via a catheter inserted from the coccygeal vein)
and the jugular vein every 15 min for 12 h (0500–1700 h) during the functional luteal
phase. Cows were fed 50% of the daily diet 6 h after the start of blood sampling. During
the 12-h sampling period, mean progesterone concentrations in the caudal vena cava did not
differ between lactating and non-lactating cows (49.0 ± 2.9 and 53.3 ± 3.7 ng/ml; mean ±
SE), whereas mean progesterone concentrations in the jugular vein in lactating cows were
higher than those in non-lactating cows (6.4 ± 0.1 and 5.6 ± 0.1 ng/ml, P < 0.001).
Lactating cows had a higher frequency of LH pulses than non-lactating cows (7.0 ± 0.7 and
4.3 ± 0.9 pulses/12 h, P<0.05). The influence of feeding was not observed on LH
profiles but was observed on progesterone profiles in both veins. Progesterone
concentrations in the caudal vena cava increased after feeding in both groups.
Progesterone concentrations in the jugular vein decreased after feeding in lactating cows
but not in non-lactating cows. These results indicate the difference in feeding-related
changes in progesterone dynamics between lactating and non-lactating cows. 相似文献
146.
Koji Nomiyama Hideki Osaki Takahide Sasaya Koichi Ishikawa 《Journal of General Plant Pathology》2013,79(1):64-68
Research on Olpidium virulentus, the vector of the serious lettuce big-vein disease, is difficult because its resting spores persist in soil and retain virus for years and the fungus is not culturable. We developed protocols to obtain purified, viable resting spores from infected roots using an enzymatic treatment and two-step density gradient centrifugation and to generate a polyclonal antibody against these spores. The antibody was species-specific in a direct immunostaining assay and in western blots produced two specific bands (ca. 30.5, 29.0 kDa) against resting spores. The detection limit for resting spores in an indirect ELISA was 200 spores/100 μL. 相似文献
147.
Fuyumi Takahashi Hideki Ogiso Masashi Fujinaga Yoshiyuki Ishiyama Yasuhiro Inoue Takashi Shirakawa Yuichi Takikawa 《Journal of General Plant Pathology》2013,79(4):260-269
In October 2010, a bacterial disease produced flecks and spots on leaves of Chinese cabbage, cabbage and Japanese radish in Nagano Prefecture, Japan. The symptoms started on the abaxial surface of leaves as angular, water-soaked flecks of 1–2 mm in diameter with a yellow halo of 3–4 mm width. These flecks then became visible on both leaf surfaces, enlarged and coalesced into large blight lesions. The symptoms were similar to bacterial leaf spot caused by Pseudomonas syringae pv. maculicola. The bacterium isolated from leaf lesions formed a white colony and produced polysaccharides on YP agar. The isolates were identified as P. syringae group by LOPAT tests and the 16S rDNA sequence. Moreover, the results of pathogenicity on cruciferous plants, bacteriological characteristics, rep-PCR and the sequences of rpoD and gyrB showed that the isolates should be identified as P. cannabina pv. alisalensis (recently transferred from P. syringae pv. alisalensis). This is the first report of P. cannabina pv. alisalensis isolated from diseased crucifers in Japan. 相似文献
148.
Shigeru Katayama Toshihiro Nishio Hideki Kishimura Hiroki Saeki 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(1):76-81
Marine brown algae are rich in sulfated polysaccharides, which have the ability to form gels and viscous solution. Sulfated
polysaccharides exhibit many biological activities; however, little is known whether the viscoelastic property in the polysaccharide
extract is correlated with biological activities. We examined the immunomodulatory properties of highly viscous polysaccharide
extract (HVPE) from Gagome Kjellmaniella crassifolia in a murine model, and the effects were compared with those of a less viscous polysaccharide extract (LVPE). HVPE or LVPE
(10, 30, and 100 mg/kg/day) were orally administered to C57BL/6 mice for 14 days. Secretions of cytokine and IgA in Con A-stimulated
spleen and Peyer’s patch (PP) cells and phagocytic activity of peritoneal macrophages was determined. IFN-γ, IL-12, IL-6,
and IgA secretions showed high levels in spleen cell cultures from mice administered HVPE, whereas these effects were diminished
in the LVPE-administered mice. The phagocytic activity of peritoneal macrophages was enhanced by the continuous oral administration
of HVPE, and these effects were higher than those of LVPE. Furthermore, an increase in IgA secretion by administration of
HVPE was observed in Con A-stimulated PP cells. These results suggest that the polysaccharide extract from K. crassifolia has immunomodulatory activities, which depend on the viscosity. 相似文献
149.
Kei’ichiro Iguchi Ken Fujimoto Hideki Kaeriyama Atsushi Tomiya Masahiro Enomoto Shin-ichiro Abe Toshinori Ishida 《Fisheries Science》2013,79(6):983-988
The Fukushima nuclear accident led to deposition of radionuclides into the freshwater fishery ground of ayu Plecoglossus altivelis. For the purpose of more comprehensive understanding of the radioactive contamination, cesium-137 (137Cs) was analyzed in running water, muddy sediment, attached algae, and ayu using samples from three river systems with different levels of contamination within Fukushima Prefecture in summer and autumn 2011. The amount of 137Cs contained in water as well as in sediment declined over an interval of two months, although the concentration in sediment samples was up to 10,000-fold higher than that in water samples. The changes in 137Cs concentration of algae showed different courses among the three river systems, the concentration being greater in autumn in the river systems with high and moderate radioactive contamination. 137Cs detected within a single stock of ayu appeared to be excreted rather rapidly with a calculated half-life of approximately 39 days, while the concentration ratio ranged from 103 to 104 l/kg, attaining higher levels than previously reported. These findings indicate that the most important pathway of 137Cs into ayu is via intake of algae as food but that the retention time of 137Cs inside ayu is relatively short. 相似文献
150.
Tsutomu Matsumoto Hideki Yamamoto Shin-ichi Fuji Masayasu Inoue 《Journal of General Plant Pathology》2008,74(1):76-80
A potyvirus tentatively named Ornithogalum virus 3 (OV-3) was successfully isolated by single-aphid transmissions from O. thyrsoides mix-infected with OV-3, Ornithogalum
mosaic
virus (OrMV) and Ornithogalum stripe mosaic virus (OrSMV). OV-3, a flexuous, rod-shaped particle of ca. 690 nm, was sap and aphid transmissible. The virus
had a narrow host range and caused necrotic mosaic on O. thyrsoides under cold conditions. We therefore propose the name Ornithogalum necrotic mosaic virus (OrNMV) for OV-3. A synergistic increase in symptom severity was apparent on O. thyrsoides mix-infected with OrSMV/OrNMV, but not with either OrMV/OrNMV or OrMV/OrSMV.
The nucleotide sequence data reported is available in the DDBJ/EMBL/GenBank databases under accession number AB282754. 相似文献