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361.
Matsumoto H Nakamura Y Hirayama M Yoshiki Y Okubo K 《Journal of agricultural and food chemistry》2002,50(18):5034-5037
The antioxidant activity of nine anthocyanin glycosides was measured in a neutral pH region using a chemiluminescence (CL) emission system in the presence of an H(2)O(2)-acetaldehyde system, and the intensities were found to be affected by three factors, pH value and both moieties of the aglycon and C-3 sugar. With an increase in pH from 4.0 to 9.0, the CL intensities increased from pH 5.0, reached their maxima at pH 6.0-7.0, and decreased at pH 9.0. Comparison of the intensities among the 3-glucosides with five different aglycons and the 3-glycosides with three different sugar moieties at C-3 showed that their strongest intensities were given by the delphinidin aglycon and 3-rutinosyl moiety, respectively. Monitoring of the CL intensity of human blood plasma for 8 h after oral administration of black currant anthocyanins (BCA) showed a rapid increase until 2 h, and a significant difference (P < 0.05) was recognized at 1-8 h. 相似文献
362.
Keiichi Koda Hitoshi Goto Hiroyuki Shintani Yuji Matsumoto Gyosuke Meshitsuka 《Journal of Wood Science》2001,47(5):362-367
Methanol liberation and methoxyl loss during chlorine bleaching of softwood kraft pulp were quantitatively investigated to estimate the degree of structural modification of lignin aromatics. An increase in the chlorine multiple led to enhanced methoxyl loss from lignin. Our result, using pH-adjusted chlorine water (pH 5.7), by which chlorination under oxidation-favorable conditions was achieved, strongly supported the importance of the oxidation reaction by chlorine during delignification and lignin degradation. It was also suggested that methanol can be produced not only via catalytic hydrolysis by chlorine but via oxidative cleavage of the ether bond as well. The infrared spectrum of chlorolignins suggested that chlorine oxidation can open aromatic rings to muconic acid derivatives without cleaving ether bonding of the methoxyl group. No straight relation between the methoxyl content and the kappa number of chlorinated pulps was shown. The methoxyl content of bleached kraft pulps subjected to successive chlorination and alkali extraction showed a good relation with the kappa number. This means that almost all the portions of the oxidatively modified lignin structure were successfully removed during these treatments, and the aromatic structures of residual lignin in chlorinated and alkali-extracted pulps were thought to remain intact.Part of this paper was presented at the 46th Annual Meeting of the Japan Wood Research Society, Kumamoto, April 1996; the 10th International Symposium on Wood and Pulping Chemistry, Yokohama, June 1999; and the 67th Pulp and Paper Research Conference, Tokyo, June 2000 相似文献
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364.
Hitoshi MIZUGUCHI Tomoki IKEDA Yumi WATANABE Shiro KUSHIBIKI Kentaro IKUTA Yo-Han KIM Shigeru SATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(6):905
The effects of anti-lipopolysaccharide (LPS) antibody on rumen fermentation and LPS activity were investigated during subacute ruminal acidosis (SARA) challenge. Eleven Holstein cattle (164 ± 14 kg) were used in a 3 × 3 Latin square design. Cattle were fed a roughage diet on days −11 to −1 (pre-challenge) and day 2 (post-challenge), and a high-grain diet on days 0 and 1 (SARA challenge). For 14 days, 0-, 2-, or 4-g of anti-LPS antibody was administered once daily through a rumen fistula. Ruminal pH was measured continuously, and rumen fluid and blood samples were collected on days −1, 0, 1, and 2. Significantly lower ruminal LPS activity on day 1 was observed in the 2- and 4-g groups than those in the 0-g group. In addition, significantly higher 1-hr mean ruminal pH on SARA challenge period (days 0 and 1) was identified in the 4-g group than in the 0-g group. However, rumen fermentation measurements (total volatile fatty acid [VFA], VFA components, NH3-N and lactic acid) and peripheral blood metabolites (glucose, free fatty acid, beta-hydroxybutyrate, total cholesterol, blood urea nitrogen, aspartate aminotransferase and gamma-glutamyl transferase) were not different among the groups during the experimental periods. Therefore, anti-LPS antibody administration mitigates LPS release and pH depression without the depression of rumen fermentation and peripheral blood metabolites during SARA challenge in Holstein cattle. 相似文献
365.
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367.
Akifumi Ogino Hitoshi Murakami Takahiro Yamashita Motohiro Furuya Hirofumi Kawahara Takako Ohkubo Takashi Osada 《Animal Science Journal》2017,88(4):659-668
We estimated the nitrogen (N), phosphorus (P), potassium (K) and magnesium (Mg) excretion factors of broiler and layer chickens in Japan, using two approaches and the latest data available. In the top‐down approach, we determined the nutrient amounts in the feeds and those in the products (i.e. the liveweight gain, eggs), and the national nutrient excretions were determined as the difference between these amounts. We then calculated the nutrient excretion factors by dividing the national excretions by the number of animals. In the bottom‐up approach, we calculated the amounts of nutrients in the feed and product per head using productivity parameters (feed conversion ratio, etc.). The differences between these amounts were considered the nutrient excretion factors. The average nutrient excretion factors of broilers (g/day/head) estimated using the top‐down and bottom‐up approaches were: N, 1.40 and 1.87; P, 0.36, 0.50; K, 0.54, 0.77; Mg, 0.13, 0.18, respectively. The excretion factors obtained by the top‐down approach can be used to calculate the national/regional excretions. The two approaches resulted in almost the same excretion factors for layers, and the average nutrient excretion factors of layers (g/day/head) estimated were: N, 2.20; P, 0.55; K, 0.68; Mg, 0.23. The estimated excretion factors for N (only) are smaller than the reported factors. 相似文献
368.
Relationships between critical photon irradiance for growth and daily compensation point of juvenile Sargassum macrocarpum 总被引:1,自引:0,他引:1
SUMMARY: This study was designed to determine the critical photon irradiance for growth and daily compensation point of juvenile Sargassum macrocarpum . Sampling and measurement of natural light conditions were carried out in the S. macrocarpum population at a depth of 8 m off Kiwado in Fukawa Bay, Yamaguchi Prefecture, Japan, from April to June 1998. Photosynthesis and respiration of the juvenile thalli, and diurnal changes in solar irradiance were measured for the same period. The critical photon irradiance for growth of the juvenile thalli observed on the population floor was 1.0–1.5% on the sea surface. The photosynthetic rate of leaf of juvenile thalli increased linearly with increasing photon irradiance when light levels were lower than 50 μM/m2 per s. The respiratory rate and light compensation point of the juvenile thalli were 2.49 μL O2 /cm2 per h and 4.98 μM/m2 per s, respectively. The daily compensation point was estimated with a mathematical model based on photosynthesis–light equations and diurnal changes in solar irradiance. For a day of average solar irradiance over the period of the present study, the estimated daily compensation point of the juvenile thalli was 1.3% on the sea surface. This value agreed well with the observed critical photon irradiance for growth of juvenile S . macrocarpum on the population floor. The results of the study confirm that the mathematical model is effective for estimating the daily compensation point. 相似文献
369.
Eishiro Okamoto Hitoshi Kasahara Akira Chiba Masayuki Taniguchi Eiichi Saitoh 《Fisheries Science》2009,75(2):463-471
We have discovered multiple acidic cysteine protease inhibitors, in addition to the known Eel-CPI-1, in the skin mucus extract
of the Japanese eel Anguilla japonica by using the two-dimensional gel system of gelatin reverse zymography. Two of the acidic inhibitors, which we have named
Eel-CPI-2 and Eel-CPI-3, were purified to homogeneity by anion exchange chromatography on a column of DEAE-Sepharose CL-6B,
followed by fast protein liquid chromatography on Superdex 75 10/300 GL and HiTrap Q HP columns. The amino acid compositions
of Eel-CPI-2 and Eel-CPI-3 were found to be almost identical and closely similar to that of the eel galectin AJL1. The molecular
masses of Eel-CPI-2 and Eel-CPI-3 were elucidated to be 16,089.080 and 16,089.137 Da, respectively, by matrix-assisted laser
desorption/ionization time-of-flight mass spectrometry. The apparent dissociation constant of Eel-CPI-2 and Eel-CPI-3 for
cysteine protease papain was determined to be 1.79 × 10−7 and 1.05 × 10−7 M, respectively, by a quartz crystal microbalance technique. 相似文献
370.
Kenji Fujino Mari Obara Hitoshi Kiuchi Hiroshi Shinada Tsutomu Nishimura Toshihiko Maekawa Yuji Hirayama 《Plant Breeding》2020,139(5):845-852
A series of DNA markers for various agronomic traits may accelerate the success of marker-assisted selection in practical plant breeding programmes. Here, we developed DNA markers for the blast resistance gene Pi-cd. In this study, we examined the effects of the Pi-cd locus on not only blast resistance but also agronomic traits in agriculture. We developed three pyramiding lines (PLs) coupling Pi-cd with three blast resistance genes, pi21, Pi35 and Pi39. The effect of Pi-cd on blast resistance was dependent on the coupled resistance genes. Then, we evaluated the effects of Pi-cd on 13 agronomic traits. Amylose content and 1,000-grain weight showed significant differences between the PLs and current commercial varieties, which had no negative effects on agronomic trait values. Furthermore, we investigated the distribution of genotype for the Pi-cd locus among varieties of upland rice. The KT genotype specific to rice blast resistance may be predominant in the varieties. The results suggested that Pi-cd has the potential to be useful for improving blast resistance in rice breeding programmes. 相似文献