The relationship of readily decomposable organic matter of the paddy soil to its colloidal complexes     

Togoro Harada  Hidenori Hashimoto  Takayuki Yoshizawa 《Soil Science and Plant Nutrition》2013,59(1):49-50

The soil nitrogen of paddy soil is found to exist in the form of organic and inorganic nitrogen. In general, the content of inorganic nitrogen is so low that it is mainly occupied by organic nitrogen. Such soil organic nitrogen is characterized by large resistance to decomposition by soil microorganisms, and so its mineralization occurs to a small extent in most cases. However, as revealed by M. Shioiri¹⁾ and T. Harada et al. ^2,3), by some appropriate treatment of paddy soil, a part of soil organic nitrogen becomes decomposed by microorganisms and mineralized under flooded condition. Among various treatment, for example, are Presented the followings: (1) air-drying of soil Prior to flooding; (2) raising the soil temperature during the flooded condition; (3) raising the soil reaction (pH 9.0) by addition of weak alkali solution; (4) the addition of neutral salts such as Nafiuoride, Na-phosphate, Na-oxalate etc., which make soil humus peptizable.  相似文献   

Evaluation of relationship between dispersibility of soils and charge characteristics using a modified ion adsorption method; An example of soils from Wakayama Prefecture,Japan     

Katsuhiko Itami  Takashi Kosaki  Kazutake Kyuma 《Soil Science and Plant Nutrition》2013,59(3):521-530

The relationship between the charge characteristics and the dispersibility of soils from reclaimed land (highly dispersive) and adjacent forest area (physically stable) was investigated.

To evaluate the amount of soil charges quantitatively, the measurement based on cation and anion adsorption (ion adsorption method) was attempted in two ways, where special attention was paid to the solution concentration. In the conventional ion adsorption method, the treatments with concentrated solutions (1 mol L^-1) were included in the process. In the modified method, soils were treated with dilute solutions (5 mmol L^-1), in taking account of the soil solution concentration in humid temperate regions. The amount of charges derived from the modified method was smaller than that from the conventional one, especially in the high pH zone. In a preliminary experiment, the extraction of polyvalent cations from soils was found to be significantly affected by the salt concentration. Thus, the use of solutions with an excessively high concentration was considered to result in an error in the estimation of the active charges in soils which would contribute to the dispersion behavior in the field.

The applicability of the modified method for analyzing the dispersion behavior of soils was evaluated by relating the dispersibility of silts and clays at different pHs with the charge characteristics determined under the same ionic strength. The dispersion ratio of silts of the reclaimed land reached maximum values at pH 5.5, above which the ratio decreased, whereas the ratio of clays began to increase in the pH range above 6. The dispersion ratio of silts of the forest area increased in the pH range above 6, whereas that of clays remained constant at a low level in all the pH ranges below 7. The changes in the dispersibility of silt plus clay fractions corresponded to total charge characteristics determined by the modified method. Thus, the evaluation of soil charges by the modified ion adsorption method was considered to be effective to predict soil dispersibility under field conditions, indicating that it could replace electrokinetic analyses such as electrophoresis in studies on the dispersion/flocculation behavior of soils.  相似文献   

Effect of Addition of Al Hydroxides on Changes in Dispersibility and Charge Characteristics of Soils     

Katsuhiko Itami  Yasuo Kitagawa  Kazutake Kyuma  Takashi Kosaki 《Soil Science and Plant Nutrition》2013,59(3):627-635

Using a soil from a newly reclaimed area where high dispersibility of fine particles had led to poor physical properties in the field, changes in dispersibility and charge characteristics after artificial precipitation of Al hydroxides onto the soil were investigated. Al hydroxides were precipitated by neutralization with NaOH of an acidic A1C1₃ solution in which the soil samples were placed.

When the titration rates were changed, no significant differences in dispersibility were observed in the resultant soils. In the systems with the addition of 2 g kg^-1 or less of A1(OH)₃, dispersion ratios of clays were almost identical with those of blank samples although the specific surface areas were reduced. In the systems with 5 g kg^-1 or more of A1(OH)₃, considerable effects of Al hydroxides on reduction of clay dispersibility were recognized (e.g. 10 g kg^-1 addition yielded less than one-third of the original ratio of the clay dispersion). A slightly larger decrease in dispersion was observed by the addition of 15 g kg^-1 or more. As the amount of added Al increased, the amount of negative charges of the soil decreased while that of positive charges increased. The charge characteristics of the system with the addition of 20 g kg^-1 of A1(OH)₃ were closer to those of the adjacent forest soil which was characterized by a very low dispersibility. It was inferred that added Al hydroxides polymerized to form Al polycation species that were not readily exchangeable, neutralizing negative charges of clays, and acting as interparticle bonding between the clays. On the other hand, forest soils were considered to have acquired a physical stability against the dispersion of fine particles as free Al oxides had been accumulated in the process of natural weathering. It was concluded that charge characteristics primarily determined the dispersion and flocculation behavior of soils and that Al hydroxides were important modifiers of charge characteristics of soils.  相似文献   

Reactivity of green tea catechins with formaldehyde   总被引：3，自引：0，他引：3  

Akiko Takagaki  Katsuhiko Fukai  Fumio Nanjo  Yukihiko Hara 《Journal of Wood Science》2000,46(4):334-338

In the reaction of green tea catechins with formaldehyde at room temperature (25°C), tea catechins were found to have reactivity. In particular, (-)-epicatechin gallate and (-)-epigallocatechin gallate, which have a galloyl moiety at the C-3 position, showed higher reactivity than (+)-catechin, (-)-epicatechin, or (-)-epigallocatechin. Reactivity of various kinds of simple phenolic compounds and flavonoids with formaldehyde was also examined. Among these compounds, only phloroglucinol showed reactivity to the same degree as that of nongalloylated catechins. These results suggest that factors for reactivity with formaldehyde at room temperature may be the presence of a phloroglucinolic A-ring structure and the absence of the electron-attractive group such as a carbonyl group in Cring. The comparison of the reactivity of 3-O-acylated catechins with that of 3-O-galloylated catechins indicated that only a galloyl group effectively enhanced reactivity with formaldehyde.  相似文献   

Effects of feeding condensed barley distillers soluble on growth rate,ruminal fermentation,plasma metabolites,and myofiber properties of the longissimus thoracis muscle in Japanese Black calves     

Katsuhiko Tsuruoka  Takami Kurahara  Hidenobu Kanamaru  Hideyuki Takahashi  Takafumi Gotoh 《Animal Science Journal》2019,90(5):637-648

This study evaluated the effects of condensed barley distillers soluble (CBDS) on growth rate, rumen fermentation, plasma metabolite, and myofiber properties, and gene expression related to metabolism in the skeletal muscles of Japanese Black calves, compared with soybean meal and corn. Twenty‐four calves were divided into four groups: fed 5% CBDS based on the hay dry matter weight (low CBDS) and fed soybean meal and corn at the same nutrition level (control); and fed 15% CBDS based on the hay dry matter weight (high CBDS) and fed soybean meal and corn at the same nutrition level (high soy). The daily gain was larger in the low (p = 0.08) and high (p < 0.05) CBDS groups compared with the control group. In the CBDS‐fed groups, plasma β‐hydroxybutyric acid concentrations were significantly higher at 6 months of age (p < 0.05), the percentage of type I myofibers was significantly lower and their diameters were significantly larger at 9 months of age (p < 0.05), and carnitine palmitoyltransferase 1b mRNA expression was significantly lower (p < 0.05) and citrate synthase mRNA expression tended to be lower (low; p = 0.06, high; p = 0.05) compared with control group. Thus, feeding CBDS promotes growth and leads to animals with more glycolytic and less oxidative muscle metabolism.  相似文献   

Microbial degradation of nonylphenol in some aquatic environments     

Katsuhiko Fujii  †  Naoto Urano  Shigeru Kimura  Yoko Nomura    Isao Karube 《Fisheries Science》2000,66(1):44-48

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Detection of intra- and interspecific variation of the dry rot fungus <Emphasis Type="Italic">Serpula lacrymans</Emphasis> by PCR-RFLP and RAPD analysis     

Sakae?HorisawaEmail author  Yoh?Sakuma  Katsuhiko?Takata  Shuichi?Doi 《Journal of Wood Science》2004,50(5):427-432

We investigated a genotype-based assay to discriminate the dry rot fungi Serpula lacrymans. DNAs were extracted from 74 isolates from the northern half of Japan, and internal transcribed spacers (ITS) were amplified by polymerase chain reaction. Genotypes of isolates were checked by restriction fragment length polymorphism (RFLP) using two enzymes, Taq I and Hha I. Among the 74 isolates identified as S. lacrymans in terms of morphologic features, 5 isolates were shown to have been misidentified. Random amplified polymorphic DNA (RAPD) analysis was conducted in order to detect the intraspecific diversity of S. lacrymans isolated in Japan. Because no relation between geographical origin and genetic distances was observed, the intraspecific diversity of S. lacrymans is suggested to be small.Part of this report was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002  相似文献   

Relationship between production of hydroxyl radicals and degradation of wood, crystalline cellulose, and a lignin-related compound or accumulation of oxalic acid in cultures of brown-rot fungi     

Shohei Kaneko  Katsuhiko Yoshitake  Shuji Itakura  Hiromi Tanaka  Akio Enoki 《Journal of Wood Science》2005,51(3):262-269

The degradation of wood, filter paper cellulose, and a lignin-substructure model, was measured in cultures of seven fungi usually regarded as brown-rot fungi. Hydroxyl radical production and the accumulation of oxalic acid in the cultures were also measured. Four of the fungi, Gloeophyllum trabeum, Tyromyces palustris, Laetiporus sulphureus, and Postia placenta, were typical brown-rot fungi, in that they preferentially degraded and eliminated the polysaccharides in wood and produced large amounts of hydroxyl radical. The rates of hydroxyl radical generation in cultures of the four fungi were directly proportional to the degradation rates of wood, cellulose, and the lignin-related compound, and inversely proportional to the amount of oxalic acid in the cultures. Two of the fungi, Daedalea dickinsii and Lentinus lepideus, did not degrade any of the substrates significantly and produced very little hydroxyl radical. Coniophora puteana had the highest rate of cellulose degradation, but did not degrade wood or the lignin model significantly and produced only negligible amounts of hydroxyl radical. These results indicate that brown-rot fungi produce large amounts of hydroxyl radical for the degradation of wood and crystalline cellulose.  相似文献   

Changes in the physical and chemical properties of six Japanese softwoods caused by lengthy smoke-heating treatment   总被引：1，自引：0，他引：1  

Futoshi Ishiguri  Noritaka Masubuchi  Shinso Yokota  Nobuo Yoshizawa 《Journal of Wood Science》2005,51(2):161-166

The effects of prolonged smoke-heating treatments on wood quality were investigated. Six Japanese softwoods were smoke-heated for 100 and 200h at a temperature of 75° ± 5°C, which was recorded inside the log. After smoke heating, wood quality, including moisture content, amounts of chemical components, relative degree of crystallinity (RDC) of cellulose, and sapwood color were examined. Moisture content decreased as a result of smoke heating, especially in sapwood, leading to a uniform distribution of moisture content within a log. Almost no difference was found in the amounts of chemical components between the control woods and the woods that were smoke-heated for 100h. However, in the wood that was smoke-heated for 200h, the amounts of holocellulose decreased, suggesting that thermal deterioration and/or degradation of hemicelluloses had occurred. We assume that the increase in RDC was caused by smoke heating with the crystallization of cellulose and/or thermal degradation of hemicelluloses. Almost no differences were found in sapwood color between the control woods and the woods that were smoke-heated for 100h. In the wood that was smoke-heated for 200h, however, L*decreased, whereas a* and b* increased. As a result, E*ab, showing the total color change, increased, resulting in a deeper color. These results suggest that thermal degradation of hemicelluloses was caused by smoke heating for over 100h. Therefore, smoke heating of softwood logs using a commercial-scale kiln should not exceed 100h.  相似文献   

Persorption of luminal antigenic molecule and its specific antibody via apoptotic epithelial cells of intestinal villi and Peyer's patches into peripheral blood in rats     

Yuji M  Tsubata M  Chin K  Onishi S  Inamoto T  Qi WM  Warita K  Yokoyama T  Hoshi N  Kitagawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(12):1297-1305

The possibility of persorption of bovine serum albumin (BSA) molecules from mucous epithelial cells and its mechanism were investigated in rats orally pre-immunized by BSA for 14 consecutive days. In the small and large intestines, both the BSA antigen (BSA-Ag) and its specific antibody (SpAb) were absorbed by the epithelial cells at the late apoptotic stage (ApoEp), and were subsequently transcytosed by membranes of the small vesicles. The basal cytoplasms containing highly-concentrated BSA-Ag and SpAb were occasionally fragmented into small cytoplasmic droplets that were secreted into the lamina propria. In Peyer's patches, both BSA-Ag and SpAb were more actively absorbed and transcytosed toward the dome area by the ApoEp of the dome apex than by the M cells. BSA-Ag and SpAb were finally persorbed into the portal blood and lymph, but were never secreted into the bile. They were also engulfed by macrophage-like cells in the villous lamina propria, mesenteric lymph node and spleen, and by hepatocytes in the liver. These findings suggest that sensitized soluble luminal antigens are taken up by ApoEp in the small intestine and are finally persorbed into the peripheral blood. The uptake of luminal antigen might be mediated by its luminal SpAb.  相似文献