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31.
Takemasa Koumoto Naoko Saito Naohiro Aoki Toshiki Iwasaki Shigenao Kawai Shuji Yokoi 《Plant Production Science》2016,19(4):497-507
We tested whether exposing rice plants to abiotic stress (salt or shade) during vegetative growth affects the chilling tolerance of reproductive organs, which is one of the most important traits for rice growing in a cool climate; we used two rice cultivars with different tolerance in two growing seasons. We divided the vegetative growth into three phases to clarify the most sensitive period: 7–22 days after transplanting (DAT), 23–38 DAT and 39–54 DAT. Chilling tolerance of the pre-stressed plants was based on the male sterility induced by low temperatures. Shade and salt stress during all three vegetative growth phases significantly reduced stomatal conductance. Shade decreased the specific leaf weight and the leaf sugar and starch contents, but salt had no significant effect, despite causing leaf damage. Low temperatures during the reproductive stage induced spikelet sterility in all plants, but the magnitude was greater in the salt- and shade-stressed plants of both cultivars, especially those stressed late during vegetative growth. The increased spikelet sterility caused by chilling was closely related to the reduction of the total spikelet number per panicle. This is the first study to show that salt and low light stress during vegetative growth increased the susceptibility of rice plants to chilling damage during panicle development. 相似文献
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Ethanol was produced from the hydrolysate collected as the water-soluble (WS) portion after hot-compressed water (HCW) treatment
of Japanese beech. The process involved saccharification with β-xylosidase followed by isomerization with xylose isomerase and fermentation with Saccharomyces cerevisiae. Several process schemes were compared to investigate the effect of process integration of saccharification, isomerization,
and fermentation. Higher ethanol yields were obtained for the processes that integrated isomerization and fermentation or
saccharification and isomerization. Integration of isomerization and fermentation was effective in converting xylose into
ethanol. Similarly, integration of saccharification and isomerization was effective in converting xylooligosaccharides into
xylulose. It is presumed that the saccharification reaction toward xylose and the isomerization reaction toward xylulose were
linked and therefore each reaction was enhanced. 相似文献
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Carotenoids, one of the most common types of natural pigments, can influence the colors of living organisms. More than 750 kinds of carotenoids have been identified. Generally, carotenoids occur in organisms at low levels. However, the total amount of carotenoids in nature has been estimated to be more than 100 million tons. There are two major types of carotenoids: carotene (solely hydrocarbons that contain no oxygen) and xanthophyll (contains oxygen). Carotenoids are lipid-soluble pigments with conjugated double bonds that exhibit robust antioxidant activity. Many carotenoids, particularly astaxanthin (ASX), are known to improve the antioxidative state and immune system, resulting in providing disease resistance, growth performance, survival, and improved egg quality in farmed fish without exhibiting any cytotoxicity or side effects. ASX cooperatively and synergistically interacts with other antioxidants such as α-tocopherol, ascorbic acid, and glutathione located in the lipophilic hydrophobic compartments of fish tissue. Moreover, ASX can modulate gene expression accompanying alterations in signal transduction by regulating reactive oxygen species (ROS) production. Hence, carotenoids could be used as chemotherapeutic supplements for farmed fish. Carotenoids are regarded as ecologically friendly functional feed additives in the aquaculture industry. 相似文献
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Hirai T Nunoya T Ihara T Saitoh T Shibuya K Nakamura K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(2):179-182
Infectivity of porcine circovirus (PCV) 1 and PCV2 was examined in primary porcine hepatocyte culture by comparing that of PCV in primary kidney cell culture. The virus titer of PCV2-infected hepatocyte cultures was higher than that of the PCV1-infected hepatocyte cultures and the PCV-infected kidney cell cultures. The number of virus-positive cells was most abundant in PCV2-infected hepatocyte cultures as determined by immunohistochemistry and/or in situ hybridization. The results of our data suggest that PCV2 preferably infects cultured hepatocytes as observed in the liver of pigs with postweaning multisystemic wasting syndrome. 相似文献
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Chiharu Tani Katsumi Takenouchi Mikiko Abe Toshiki Uchiumi Akihiro Suzuki 《Soil Science and Plant Nutrition》2013,59(1):137-142
Abstract A method which uses the pressure head to predict unsaturated hydraulic conductivity is presented to calculate the soil water flux in a field. Hydraulic conductivities in the primary drying and wetting processes were measured with core samples in the laboratory and the hysteresis between the hydraulic conductivity and pressure head was taken into account. Hydraulic gradients were measured every hour with tensiometers installed in the field. This method was applied to analyze the water movement at 94-cm depth in Hydric Hapludands. Downward or upward flow of water by summing soil water fluxes was examined using the water balance method. Amounts of downward flow determined by our method after heavy rain in a wet soil were slightly larger in the soybean plot but smaller in the bare plot than those obtained by the water balance method due to non-uniform infiltration. Water balance equation which used values of upward flow across a 94-cm depth estimated reasonably well the evapotranspiration from the soybean plot and the evaporation from the bare plot during a dry period. Effect of initial soil water conditions on downward flux by rainfall was well monitored by our method. 相似文献
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The protective effect of stevia extract on the gastric mucosa of rainbow trout Oncorhynchus mykiss (Walbaum) fed dietary histamine 总被引：1，自引：0，他引：1
Kazuhiro Shiozaki Toshiki Nakano Toshiyasu Yamaguchi Minoru Sato & Naohiko Sato 《Aquaculture Research》2004,35(15):1421-1428
Stevia extract was made from stevia stem by extraction with boiling water and fermentation. The protective effect of a Stevia extract on rainbow trout (average weight, 12 g) fed 1% of dietary histamine for 4 weeks was investigated. Administration of dietary histamine to trout did not result in a reduction in growth rate or feed consumption but caused a gastric abnormality, e.g. exfoliation of the mucosal epithelium and atrophy of mucosal lamina propria. Stevia extract protected gastric tissue from histamine‐induced damage. Pepsin activity in gastric fluid increased and liver α‐tocopherol content was reduced after histamine treatment, but Stevia treatment prevented these abnormalities. The results suggest that the stevia extract might protect the rainbow trout stomach from histamine toxicity. 相似文献
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Minoru Sato Zhi Hua Tao Kazuhiro Shiozaki Toshiki Nakano Toshiyasu Yamaguchi Takehiko Yokoyama Nobuhiro Kan-No Eizoh Nagahisa 《Fisheries Science》2006,72(4):889-892
ABSTRACT: The described analytical method for histamine determination in fish and seafood consists of sample extraction, adsorption onto a paper disc, application of the paper disc onto electrophoresis paper, electrophoresis for only 10 min, drying, and color developing by Pauly's reagent. Histamine can be satisfactorily detected and completely separated from histidine, carnosine and other Pauly reagent-positive compounds. This method does not require expensive instrumentation and any tedious pretreatment to eliminate potential interference by other imidazole compounds, such as histidine or carnosine. This method can be used to detect histamine in multiple fish and seafood samples simultaneously that contain as little as 15 p.p.m. histamine (1.5 mg/100 g). 相似文献
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Kawamura-Konishi Y Watanabe N Saito M Nakajima N Sakaki T Katayama T Enomoto T 《Journal of agricultural and food chemistry》2012,60(22):5565-5570
Ethanol extracts from 15 kinds of marine algae collected from the coast of the Noto Peninsula in Japan were examined for their inhibitory effects on human salivary α-amylase. Four extracts significantly suppressed the enzyme activity. An inhibitor was purified from the extract of Sargassum patens . The compound was a new phloroglucinol derivative, 2-(4-(3,5-dihydroxyphenoxy)-3,5-dihydroxyphenoxy) benzene-1,3,5-triol (DDBT), which strongly suppressed the hydrolysis of amylopectin by human salivary and pancreatic α-amylases. The 50% inhibitory activity (IC(50)) for α-amylase inhibition of DDBT (3.2 μg/mL) was much lower than that of commercially available α-amylase inhibitors, acarbose (26.3 μg/mL), quercetagetin (764 μg/mL), and α-amylase inhibitor from Triticum aestivum (88.3 μg/mL). A kinetic study indicated that DDBT was a competitive α-amylase inhibitor with a K(i) of 1.8 μg/mL. DDBT also inhibited rat intestinal α-glucosidase with an IC(50) value of 25.4 μg/mL for sucrase activity and 114 μg/mL for maltase activity. These results suggest that DDBT, a potent inhibitor of carbohydrate-hydrolyzing enzymes, may be useful as a natural nutraceutical to prevent diabetes. 相似文献