Delignification of cell walls of <Emphasis Type="Italic">Chamaecyparis obtusa</Emphasis> during alkaline nitrobenzene oxidation     

Arata?YoshinagaEmail author  Seizo?Ohno  Minoru?Fujita 《Journal of Wood Science》2004,50(4):287-294

To clarify the behavior of whole lignins in wood cell walls during alkaline nitrobenzene oxidation, the delignification process from cell walls in normal and compression woods of Chamaecyparis obtusa Endl. (Cupressaceae) was observed using ultraviolet and transmission electron microscopies. The lignin content conspicuously decreased to around 10% after 35min in normal wood. The lignin content in compression wood finally leveled off at aroumd 10% after 50min. In gel filtration of oxidation products in ethyl acetate, a high molecular weight fraction was prominent in extracts from the early stage of the reaction. As the oxidation progressed, the high molecular weight fraction became less prominent in both normal and compression wood. Changes in the weights of cell wall residues during reaction indicated that approximately half of the components other than lignin were also removed from the cell walls. This shows that the majority of lignin with relatively high molecular weight is removed from the cell walls together with polysaccharides in the early stage of the reaction and that further oxidative degradation occurs in solution in later stages. Only a small amount of the lignin with low molecular weight could be analyzed by gas chromatography.Parts of this report were presented at the 47th (Kochi, April 1997) and 48th (Shizuoka, April 1998) Annual Meetings of the Japan Wood Research Society, and at the Lignin Symposium, Sapporo, October 1997  相似文献   

Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment in an aerobic bioreactor packed with carbon fibers          下载免费PDF全文

Takahiro Yamashita  Ryoko Yamamoto‐Ikemoto  Hiroshi Yokoyama  Hirofumi Kawahara  Akifumi Ogino  Takashi Osada 《Animal Science Journal》2015,86(3):358-368

Mitigation of nitrous oxide (N₂O) emission from swine wastewater treatment was demonstrated in an aerobic bioreactor packed with carbon fibers (CF reactor). The CF reactor had a demonstrated advantage in mitigating N₂O emission and avoiding NOx (NO₃ + NO₂) accumulation. The N₂O emission factor was 0.0003 g N₂O‐N/gTN‐load in the CF bioreactor compared to 0.03 gN₂O‐N/gTN‐load in an activated sludge reactor (AS reactor). N₂O and CH₄ emissions from the CF reactor were 42 g‐CO₂ eq/m³/day, while those from the AS reactor were 725 g‐CO₂ eq/m³/day. The dissolved inorganic nitrogen (DIN) in the CF reactor removed an average of 156 mg/L of the NH₄‐N, and accumulated an average of 14 mg/L of the NO₃‐N. In contrast, the DIN in the AS reactor removed an average 144 mg/L of the NH₄‐N and accumulated an average 183 mg/L of the NO₃‐N. NO₂‐N was almost undetectable in both reactors.  相似文献   

Enantioseparation of isoxanthohumol in beer by hydroxypropyl-gamma-cyclodextrin-modified micellar electrokinetic chromatography     

Kodama S  Yamamoto A  Sato A  Suzuki K  Yamashita T  Kemmei T  Taga A  Hayakawa K 《Journal of agricultural and food chemistry》2007,55(16):6547-6552

Chiral resolution of isoxanthohumol (IX) in beer samples was performed by hydroxypropyl-gamma-cyclodextrin-modified micellar electrokinetic chromatography. The optimum running conditions were found to be 20 mM phosphate buffer (pH 7.0) containing 45 mM hydroxypropyl-gamma-cyclodextrin and 100 mM sodium dodecyl sulfate with an effective voltage of +20 kV at 20 degrees C using direct detection at 210, 295, and 370 nm. IX was detected in 12 beer samples and the total levels of (+)- and (-)-IX ranged from 0.15 to 1.4 mg/L. But the amount of xanthohumol (XN) was below the detection limit (0.017 mg/L). Each level of (-)-IX was almost the same as that of (+)-IX, suggesting that IX was a racemic mixture in these beer samples. The racemization of IX in beer could be attributed to the production of a racemic mixture from XN during boiling and to the fact that IX enantiomers were easily interconverted.  相似文献   

Osmo-responsive expression of oyster amino acid transporter gene and analysis of the regulatory region involved     

Haruhiko?ToyoharaEmail author  Masashi?Ikeda  Chika?Goto  Hideki?Sawada  Masatomi?Hosoi  Kazuaki?Takeuchi  Isao?Hayashi  Shintaro?Imamura  Michiaki?Yamashita 《Fisheries Science》2005,71(3):465-470

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Effect of improvement cutting on the community structure of aphyllophoraceous fungi on Okinawa Island     

Satoshi Yamashita  Tsutomu Hattori  Shin Abe  Hideaki Goto  Hiroki Sato 《Journal of Forest Research》2014,19(1):143-153

Improvement cutting, which decreases tree density by cutting and thinning while leaving logging residues, has been practiced on Okinawa Island since the 1970s and changes not only the vegetation composition but also the amount and composition of woody debris on the forest floor. To quantitatively compare the effect of improvement cutting with the effects of woody debris and vegetation on the community structure of aphyllophoraceous fungi, we conducted a field survey of vegetation composition, the amount and composition of woody debris, and the aphyllophoraceous fungi flora on Okinawa Island in December 2006. We established 3 plots in forest stands without logging and 13 plots in a forest that had undergone improvement cutting from 1 to 22 years before our field survey. The number and volume of woody debris tended to be highest soon after improvement cutting. We recorded 1,172 fungal samples belonging to 81 species in four orders. Fungal species richness was correlated with the composition of the woody debris. Fungal species composition in forest plots 1 year after improvement cutting differed from most of the other logged forests. Variation partitioning revealed that the effects of improvement cutting explained 14.1 % of the total variation in fungal species composition, and that differences in woody debris and vegetation not related to improvement cutting explained 40.4 %. Changes in the composition of woody debris caused by improvement cutting explained at most 2.7 % of the variation. This suggests that improvement cutting does not have a strong effect on fungal community structure, but woody debris does.  相似文献   

Seed productivity test of CMS lines of Japanese bunching onion (Allium fistulosum L.) possessing the cytoplasm of a wild species, A. galanthum Kar. et Kir.     

Ken-ichiro Yamashita  Yosuke Tashiro 《Euphytica》2004,136(3):327-331

In a previous study, we developed male sterile lines of Japanese bunching onion (Allium fistulosum L.) possessing the cytoplasm of a wild species, A. galanthum Kar. et Kir., by backcrossing. To evaluate seed productivity of the male sterile lines in practise, they were crossed with the male fertile line, cultivar 'Kujyo', using honeybees as pollinators under field conditions. The number of florets and seeds per inflorescence, seed set and seed germination of the material were investigated. Although variation was observed among the male sterile lines, there were several lines having seed productivity equal to cultivar 'Kujyo'. Our data demonstrate that the male sterile lines of A. fistulosum possessing the cytoplasm of A. galanthum are useful as seed parents for the commercial F seed production of A. fistulosum.  相似文献   

Two male sterility-inducing cytoplasms of beet (Beta vulgaris) are genetically distinct but have closely related mitochondrial genomes: implication of a substoichiometric mitochondrial DNA molecule in their evolution     

Yasuyuki Onodera  Takumi Arakawa  Rika Yui-Kurino  Masayuki P. Yamamoto  Kazuyoshi Kitazaki  Shigehiko Ebe  Muneyuki Matsunaga  Kazunori Taguchi  Yosuke Kuroda  Shiko Yamashita  Tomoyuki Sakai  Toshiro Kinoshita  Tetsuo Mikami  Tomohiko Kubo 《Euphytica》2015,206(2):365-379

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Bow variation in kiln-dried boxed-heart square timber of sugi (<Emphasis Type="Italic">Cryptomeria japonica</Emphasis>) cultivars     

Kana Yamashita  Yasuhiko Hirakawa  Shuetsu Saito  Hiroshi Nakatani  Motoyoshi Ikeda 《Journal of Wood Science》2011,57(5):363-370

To evaluate the bow variation in boxed-heart square timber of sugi (Cryptomeria japonica), bows from kiln-dried timber for five sugi cultivars with different longitudinal shrinkage trends were compared for two stem heights. Two general trends were observed, depending on the cultivar: (1) either the bow was larger at the lower than at the upper part of the stem, or (2) the bows at the lower and the upper parts of the stem were similar. In timber that had larger bow values, the gradients of longitudinal shrinkage were large across the radius and along the length of the timber. There was a positive relationship between the bow and longitudinal shrinkage. These results suggest that the bow variation between the timbers was caused by a variation in longitudinal shrinkage, which was affected by the microfibril angle. Furthermore, the bow was inversely proportional to the modulus of elasticity, which suggests that timber with a low modulus of elasticity is susceptible to a large bow due to large longitudinal shrinkage.  相似文献   

Identification of a novel cytotoxic protein, Cry45Aa, from Bacillus thuringiensis A1470 and its selective cytotoxic activity against various mammalian cell lines     

Okumura S  Saitoh H  Ishikawa T  Wasano N  Yamashita S  Kusumoto K  Akao T  Mizuki E  Ohba M  Inouye K 《Journal of agricultural and food chemistry》2005,53(16):6313-6318

Parasporal inclusion proteins produced by Bacillus thuringiensis strain A1470 exhibit strong cytotoxicity against human leukemic T cells when activated by protease treatment. One of the cytotoxic proteins was separated by anion exchange chromatography and gel filtration chromatography and designated Cry45Aa. Its gene was then expressed in recombinant Escherichia coli, in which the Cry45Aa precursor was accumulated in an inclusion body. It was solubilized in sodium carbonate buffer and processed with proteinase K, and cytotoxic activities of the protein against various mammalian cell lines were evaluated using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide assay. The protein exhibited high cytotoxic activity against CACO-2, Sawano, MOLT-4, TCS, and HL60 cells and moderate activity against U-937 DE-4, PC12, and HepG2 cells. On the other hand, the EC50 values against Jurkat, K562, HeLa, A549, Vero, COS-7, NIH3T3, CHO, and four normal tissue cells (human primary hepatocyte cells, UtSMC, MRC-5, and normal T cells) were >2 microg/mL.  相似文献   

Subaru telescope observations of Deep Impact     

Sugita S  Ootsubo T  Kadono T  Honda M  Sako S  Miyata T  Sakon I  Yamashita T  Kawakita H  Fujiwara H  Fujiyoshi T  Takato N  Fuse T  Watanabe J  Furusho R  Hasegawa S  Kasuga T  Sekiguchi T  Kinoshita D  Meech KJ  Wooden DH  Ip WH  A'Hearn MF 《Science (New York, N.Y.)》2005,310(5746):274-278

The impact cratering process on a comet is controversial but holds the key for interpreting observations of the Deep Impact collision with comet 9P/Tempel 1. Mid-infrared data from the Cooled Mid-Infrared Camera and Spectrometer (COMICS) of the Subaru Telescope indicate that the large-scale dust plume ejected by the impact contained a large mass (approximately 10(6) kilograms) of dust and formed two wings approximately +/-45 degrees from the symmetric center, both consistent with gravity as the primary control on the impact and its immediate aftermath. The dust distribution in the inner part of the plume, however, is inconsistent with a pure gravity control and implies that evaporation and expansion of volatiles accelerated dust.  相似文献