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51.
Takayuki Kobayashi Hiroyasu Taguchi Mikiji Shigematsu Mitsuhiko Tanahashi 《Journal of Wood Science》2005,51(6):607-614
The consumption rates of three monolignols (p-coumaryl, coniferyl, and sinapyl alcohols) and eight analogues using horseradish peroxidase (HRP)–H2O2 as an oxidant were measured and compared with the anodic peak potentials thereof measured with cyclic voltammetry. 3-Monosubstituted
p-coumaryl alcohols, i.e., 3-methoxy-, 3-ethoxy-, 3-n-propoxy-, and 3-n-butoxy-p-coumaryl alcohols, had faster reaction rates than p-coumaryl alcohol. This is most probably due to the electron-donating effect of alkoxyl groups. However, the reaction rates
gradually decreased with an increase in the molecular weight of the alkoxyl groups. Furthermore, t-butoxyl group, which is a very bulky substituent, caused an extreme reduction in the reaction rate, even though its electron-donating
effect was almost the same as that of other alkoxyl groups. The reaction rates of 3,5-disubstituted p-coumaryl alcohols, especially 3,5-dimethyl-p-coumaryl alcohol, were very low compared with 3-monosubstituted p-coumaryl alcohols. These results suggest that there are three main factors of hindrance during the approach of monolignols
to the active site of HRP. First, from the results of 3-monoalkoxy-p-coumaryl alcohols, it was suggested that the volume of substituents could decrease their oxidation rates. Second, from the
results of 3,5-disubstituted p-coumaryl alcohols, it was suggested that local steric hindrance by the amino residues quite near the heme decreased the oxidation
rates. Third, from the results of the substrates with hydrophobic substituents at their 3,5-positions, we suggested that hydrophilicity
near heme would decrease their oxidation rates. 相似文献
52.
刘璨 Maxim Lobovikov Daniel Murdiyarso Hiroyasu O-ka Yeo-Chang Youn Keith Barney Makoto Inoue Hariadi Kartodi-hardjo Pia Katila Tetsuya Saito Bintang Simangunsong Yasuhiro Yokota 吕金芝 林海燕 《绿色中国(A版)》2005,(18):19-22
在过去的20年里,亚洲林业经历了引人注目的转型,包括从计划经济到市场经济的转变,从天然林供给木材到人工林供给木材的转变,木材替代品与非木质林产品的增加,地方分权与当地群众的参与,生态时代的发展与生态系统管理。在促进亚洲可持续森林资源管理中,市场工具、社区参与和环境服务都得到了应用。亚洲林业的转型表现出多样化,其森林、社会与环境之间的联系是丰富多彩的。 相似文献
53.
54.
Masayuki YAMAMOTO Hiroyasu MAKINO Tetsushi KAGAWA Osamu TOMINAGA 《Fisheries Science》2004,70(6):1089-1097
ABSTRACT: The occurrence and distribution of larval and juvenile Japanese flounder Paralichthys olivaceus and major demersal fish from May to September were examined at seven sandy beaches at the central Seto Inland Sea. The flounder appeared from late May to August and were mainly collected at a depth of 2–5 m. Settlement of larval flounder was seen from late May to late June. A total of 6412 individuals of 17 species representing 12 families were collected in the study area. The dominant fish species were Favonigobius gymnauchen (56.0%), Tarphops oligolepis (8.1%), Rudarius ercodes (7.8%), P. olivaceus (7.3%), Repomucenus spp. (7.0%) and Heteromycteris japonica (3.3%). The catches of flounder differed among beaches and months. The number of flounder in June at Ohama Beach, where the most flounder were collected, was 22.6 individuals per haul (400 m2 ). The density of the flounder correlated negatively to that of F. gymnauchen . 相似文献
55.
Hidetoshi Minamiyama Masafumi Shimizu Hitoshi Kunoh Tamotsu Furumai Yasuhiro Igarashi Hiroyasu Onaka Ryuji Yoshida 《Journal of General Plant Pathology》2003,69(1):65-70
An endophytic actinomycete, isolate R-5 of Streptomyces galbus Frommer, that has promising potential as a biocontrol agent was originally isolated from field-grown rhododendron. In this
study, the mode of entry of R-5 into leaves of tissue-cultured seedlings of rhododendron was investigated in connection with
its production of cell wall-degrading enzymes. Light and scanning electron microscopy (SEM) revealed that R-5 grew on leaf
surfaces and entered leaf tissues via stomata and that the internal mycelia grew out of stomata after colonization in host
tissues. Micromanipulation at the SEM level demonstrated a prominent depression in the host surface at the interfaces with
the mycelia, suggesting that such a depression could be caused by degradation of cell wall components by hydrolytic enzymes
secreted from R-5 mycelia. In subsequent plate assays, R-5 produced cellulase, pectinase, xylanase, and nonspecific esterase
when cultured in liquid medium. Moreover, R-5 multiplied in mineral medium containing cellulose, pectin, or xylan as a single
carbon source. Thus, R-5 mycelia could degrade host cell walls at contact sites and probably utilize the degradation products
as carbon sources.
Received: May 16, 2002 / Accepted: July 9, 2002 相似文献
56.
Mitsuo Matsumoto Hiroyasu Oka Yasushi Mitsuda Shoji Hashimoto Chihiro Kayo Yuko Tsunetsugu Mario Tonosaki 《Journal of Forest Research》2016,21(5):211-222
By considering trade-offs and complementarity between carbon removal from the atmosphere by forests and emission reduction by wood use, we developed a forest-sector carbon integrated model for Japan. We discuss mitigation measures for Japan based on model projections. The integrated model included the forest model and the wood use model. Based on three scenarios (baseline, moderate increase, and rapid increase) of harvesting and wood use, the integrated model projected mitigation effects including carbon removal by forests and emission reduction through the wider use of wood, until 2050. Results indicate that forests will not become a source of net carbon emissions under the three scenarios considered. The baseline scenario is most effective for mitigating climate change, for most periods. However, the sum total of carbon removal in forests and carbon emission reductions by wood use under the rapid increase scenario exceeded the one of the moderate increase scenario after 2043. This was because of strong mitigation activities: promoting replanting, using new high-yield varieties, and wood use. The results also indicated that increases in emission reduction due to greater wood use compensated for 67.9 % of the decrease of carbon removal in 2050, for the rapid increase scenario. The results show that carbon removal in forests is most important in the short term because of the relative youth of the planted forests in Japan, and that mitigation effects by material and energy substitution may become greater over the longer term. 相似文献
57.
Takagaki M Kaku K Watanabe S Kawai K Shimizu T Sawada H Kumakura K Nagayama K 《Pest management science》2004,60(9):921-926
The inhibitory activity of carpropamid on scytalone dehydratase (SDH) extracted from a carpropamid-resistant strain of Magnaporthe grisea (Hebert) Barr was dramatically reduced in comparison with that on SDH extracted from the sensitive strain. A single-point mutation (G to A) located at the upstream region (233 bp downstream from the ATG codon) resulting in a one-amino-acid substitution (valine [GTG] 75 to methionine [ATG]: V75M) was found in the resistant strain. To examine whether the V75M mutation is the primary reason for decreasing the sensitivity of SDH to carpropamid, the SDH cDNAs of both the sensitive and the resistant strain were cloned into a GST-fused protein expression vector-system. The recombinant SDHs of both strains exhibited the same sensitivities to carpropamid as those extracted from the mycelia of the respective strains. These data clearly revealed that the V75M mutation causes the low sensitivities of the SDHs of the carpropamid-resistant strains, and strongly suggests that the V75M mutation confers resistance of these strains to carpropamid. 相似文献
58.
Yuri Hirayama Rie Takishita Hiroyasu Misawa Kazuhiro Kikuchi Koji Misumi Sachiko Egawa Sawako Motoyama Yasunobu Hasuta Yoshiyuki Nakamura Yutaka Hashiyada 《Animal Science Journal》2020,91(1)
This study aimed to compare the efficiency of non‐surgical embryo transfer (ET) using a newly developed catheter, which enables transferring embryos into a proximal site of the uterus (mostly uterine body), and surgical ET of vitrified porcine embryos. In Experiment 1, the catheter was inserted into 12 gilts, with each half of the group allocated to skilled or novice operators. The time required for insertion into the uterus did not differ between skilled and novice operators (4 min 9 s and 4 min 6 s, respectively). In Experiment 2, 12 gilts were used as recipients for non‐surgical and surgical ET with vitrified embryos (n = 6, each). There was no significant difference in the rate of piglet production based on the number of transferred embryos between surgical and non‐surgical ET (25.8% vs. 15.4%, p = .098). The results suggest that non‐surgical ET catheter allowed for easy insertion and transfer of embryos without special training. Although the catheter is effective for deposition of embryos into the proximal site of uterus, the efficiency of piglet production is not enhanced compared with surgical ET. The ET method using this catheter, being labor‐saving and less‐invasive, may contribute to the improvement of ET in pigs. 相似文献
59.
N. Kumakura K. Okuzawa S. Yamaguchi K. Gen B.S. Lim H. Kagawa 《Fish physiology and biochemistry》2003,28(1-4):99-100
We examined the effects of gonadotropin-releasing hormone agonist (GnRHa) and testosterone (T) on the level of gonadotropin subunit mRNAs in the pituitary of ovariectomized or intact female red seabream. Ovariectomy induced increase of seabream (sb) GnRH, glycoprotein (GP) α and luteinizing hormone (LH) β mRNA levels. GnRHa treatment also stimulated GPα and LHβ mRNA levels. T treatment reduced GPα and LHβ mRNA expression probably via negative feedback action on sbGnRH. Both GnRHa and T treatment had no effect on follicle-stimulating hormone (FSH) β mRNA levels. These results suggest that the regulatory mechanisms of GPα and LHβ gene expression differ from those of FSHβ gene. 相似文献
60.
Koichi Okuzawa Naoki Kumakura Koichiro Gen Sonoko Yamaguchi Bong-Soo Lim Hirohiko Kagawa 《Fish physiology and biochemistry》2003,28(1-4):439-440
In the present study, we examined the effect of high water temperature on brain-pituitary-gonad (B-P-G) axis of a perciform fish red seabream, Pagrus (Chrysophrys) major during its spawning season (April-May). High water temperature negatively affected all levels in B-P-G axis and turned out to be the termination factor of the spawning season of this species. 相似文献