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1.
To search for edible herbal extracts with potent antioxidant activity, we conducted a large scale screening based on the superoxide scavenging activity. That is, scavenging activity against superoxide anions were extensively screened from ethanol extracts of approximately 1,000 kinds of herbs by applying an electron spin resonance (ESR)-spin trapping method. Among them we chose four edible herbal extracts with prominently potent ability to reduce the signal intensity of 5,5-dimethyl-1-pyrroline-N-oxide (DMPO)-OOH, a spin adduct formed by DMPO and superoxide anion. They are the extracts from Punica granatum (Peel), Syzygium aromaticum (Bud), Mangifera indica (Kernel), and Phyllanthus emblica (Fruit), and are allowed to be used as foodstuffs according to the Japanese legal regulation. The ESR-spin trapping method coupled with steady state kinetic analysis showed that all of the four extracts directly scavenge superoxide anions, and that the superoxide scavenging potential of any of the extracts was comparable to that of L-ascorbic acid. Furthermore, polyphenol determination indicates that the activity is at least in part attributable to polyphenols. These results with such large scale screening might give useful information when choosing a potent antioxidant as a foodstuff.  相似文献   
2.
The gene constitution of polymorphisms of the four calpain genes (µ‐calpain, m‐calpain, p94, and µ/m‐calpain) were analyzed in South‐East Asian native chickens, White Leghorn and Broiler commercial chickens, and Red and Green jungle fowl. Polymorphisms were detected at all loci in chickens and Red jungle fowl, but only for CAPN1 (µ‐calpain gene) in Green jungle fowl. CAPN2 and CAPN1.5 are linked on chicken chromosome 3, and the genotype for these loci were treated as haplotype. Some combinations of calpain loci were tested using principal component analysis, and the best combination (CAPN1, CAPN3, and CAPN1.5) was determined. The proportion of polymorphic loci (Ppoly) and heterozygosity (H?) were 1.00 and 0.316–0.465 in domestic chickens and red jungle fowl, and 0.33 and 0.137 in Green jungle fowl, respectively. GST values suggested that the degree of subdivision among native chickens was relatively low except for Thailand, which was highest. Pair‐wise FST testing, dendrogram and principal component analysis from the results of calpain loci showed that the four South‐East Asian native and commercial chicken populations were close genetically.  相似文献   
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Anionic emulsion sizes consisting of rosin triglyceride esters and partly fortified rosin acids (i.e., rosin-ester sizes), have recently been used as internal sizes for alkaline papermaking. In this study, handsheets were prepared from pulp suspensions with alum and a rosin-ester size under various conditions, and sizing degree and size and aluminum contents of the handsheets were determined. Aluminum compounds originating from alum added to the pulp suspensions behave as retention aids of the rosin-ester size even in alkaline papermaking under limited conditions. Carboxyl groups in pulp are the primary retention sites of aluminum compounds in pulp suspensions. They form cationic sites on pulp fibers, and thus the anionic size emulsion particles are adsorbed on pulp fibers by electrostatic interactions. However, the cationic charges of aluminum compounds on pulp fibers decrease and finally disappear completely with the lapse of time after the alum addition by forming ionic bonds between the cationic sites and OH ions. Thus, pH values of the pulp suspensions and timing of the size addition strongly influence the retention values of the rosin-ester size and the resultant sizing features.This research was presented in part at the 1995 autumn meetings of the Society of Fiber Science and Technology Japan in Hamamatsu, October 1995  相似文献   
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For sustainable control of rice blast with fungicides, efficient monitoring of the emergence and spread of fungicide-resistant isolates is needed. We developed simple and reliable PCR-based DNA markers to detect isolates resistant to melanin biosynthesis inhibitor targeting scytalone dehydratase (MBI-D) and quinone outside inhibitor (QoI) fungicides. Through the use of DNA templates prepared from mycelia on filter paper or from infected leaves, these markers enable rapid (a few hours) genotyping of point mutations that confer resistance. The developed multiplex marker detected resistance to both MBI-D and QoI in a single PCR and further reduced the time needed for diagnosis.  相似文献   
7.
Abstract

Biochar application has been recognized as an effective option for promoting carbon (C) sequestration, but it may also affect the production and consumption of methane (CH4) and nitrous oxide (N2O) in soil. A 1-year field experiment was conducted to investigate the effects of rice husk charcoal application on rice (Oryza sativa L.) productivity and the balance of greenhouse gas exchanges in an Andosol paddy field. The experiment compared the treatments of rice husk charcoal applied at 10, 20 and 40 Mg ha?1 (RC10, RC20 and RC40, respectively), rice husk applied at 20 Mg ha?1 (RH20), and the control (CONT). Rice straw and grain yields did not significantly differ among the treatments. The seasonal cumulative CH4 emissions were 38–47% higher from RC10, RC20 and RC40 than from the CONT. However, the increases were not in proportion to the application rates of rice husk charcoal, and their values did not significantly differ from the CONT. On the contrary, the RH20 treatment significantly increased the cumulative CH4 emission by 227% compared to the CONT. The N2O emissions during the measurement were not affected by the treatments. As a result, the combined global warming potential (GWP) of CH4 and N2O emissions was significantly higher in RH20 than in the other treatments. There was a positive linear correlation between C storage in the top 10 cm of soil and the application rate of rice husk charcoal. The increases in soil C contents compared to the CONT corresponded to 98–149% of the C amounts added as rice husk charcoal and 41% of the C added as rice husk. Carbon dioxide (CO2) fluxes in the off season were not significantly different among RC10, RC20, RC40 and CONT, indicating that C added as rice husk charcoal remained in the soil during the fallow period. The CO2 equivalent balance between soil C sequestration and the combined GWP indicates that the rice husk charcoal treatments stored more C in soil than the CONT, whereas the RH20 emitted more C than the CONT. These results suggest that rice husk charcoal application will contribute to mitigating global warming without sacrificing rice yields.  相似文献   
8.
Coated paper-to-coated paper friction properties were examined in relation to printing runnability difficulties like erroneous double feeding of paper sheets. Higher ratios of precipitated calcium carbonate (PCC) to clay in mixed pigment coatings resulted in higher static and kinetic coefficients of friction (COFs). Microroughness in the order of pigment particle size is considered to relate to COF, because cube-shaped particles of PCC resist sliding. Calendering decreased COF at larger amounts of PCC, but did not change COF of the sole clay formulation at all. Addition of ground calcium carbonate (GCC) decreased COF. The rate of decrease in kinetic COF with increasing number of sliding for the GCC-rich formulation was higher than that for the PCC-rich formulation, presumably because protruding parts, characteristic of the GCC-rich formulation, on the surface were selectively flattened. Addition of styrene-butadiene (SB)-latex up to 14pph decreased COF, but static COF had the highest value at 18pph. The antislip property (as a rubber) of SB-latex developed only in the static mode. Among lubricants formulated, the wax type decreased COF the most remarkably with more effect on kinetic COF than on static COF. Part of this report was presented at the 11th International Printing and Graphic Arts Conference, Bordeaux, France, October 2002  相似文献   
9.
A survey was made of seasonal changes in pH and electronic conductivity (EC) of precipitation inAlnus japonica (Thunb.) Steud. forest in Kiritapp mire, Hokkaido, Japan. The average pH of throughfall and stem flow was higher than that of bulk deposition. When the pH of bulk deposition exceeded 5.5, however, pH of throughfall and stem flow was lower than that of bulk deposition. The EC of stem flow was always higher than throughfall, and that of throughfall higher than that of bulk deposition. The EC of stem flow was highest during the first defoliation period ofA. japonica. On the other hand, the differences in the EC of throughfall and bulk deposition was very few just after the first defoliation period ofA. japonica. This implies that the chemical properties of throughfall and stem flow are strongly affected by the phenology of the plants.  相似文献   
10.
To evaluate the diversity of extended-spectrum β-lactamases (ESBL) genes among food-producing animals, 48 isolates of ESBL-producing Escherichia coli isolates were obtained from rectal samples of broilers, layers, beef cattle and pigs, at the slaughterhouse level. ESBL-carrying E. coli were isolated from 60.0% of individual broiler rectal samples, 5.9% of layers, 12.5% of beef cattle and 3% of pigs. One ESBL-producing Klebsiella pneumoniae was isolated from a broiler. The ESBL-positive E. coli isolates from broilers harbored various ESBL genes: bla (SHV-12), bla(CTX-M-2), bla(CTX-M-14), bla(CTX-M-15) and bla(CTX-M-44). The plasmid DNAs were analyzed by restriction patterns. Homogeneous band patterns were yielded in those of K. pneumoniae and E. coli isolates harboring the bla(CTX-M-2) gene from different farms. No genetic relation between the 2 CTX-M-14 ESBL-producing strains was found by pulsed-field gel electrophoresis, although 2 plasmids in these strains, obtained from different broiler farms, were similar to each other. This study provides evidence that the proliferation of CTX-M-producing E. coli is due to the growth of indigenous CTX-M-producing strains and the possible emergence of strains that acquired CTX-M genes by horizontal transfer in different broiler farms. CTX-M-producing coliforms in broilers should be controlled due to the critical importance of cephalosporins and the zoonotic potential of ESBL-producing bacteria.  相似文献   
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