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301.
Taku Tsuyama Natsumi Shimada Taichi Motoda Yasuyuki Matsushita Yoshio Kijidani Kazuhiko Fukushima Ichiro Kamei 《Journal of Wood Science》2017,63(6):551-559
Bamboos are among the largest woody grasses and grow very rapidly. Although lignin is a crucial factor for the utilization of bamboo biomass, the lignification mechanism of bamboo shoots is poorly understood. We studied lignification in the bamboo Sinobambusa tootsik during culm development. Elongation growth began in May and ended in late-June, when the lignin content was approximately half that in mature culms. Thioacidolysis analysis indicated that p-hydroxyphenyl units in lignin formed even at late stages of lignification. The syringyl/guaiacyl ratio varied during culm development. Various lignin precursors were detected in developing culms by liquid chromatography–mass spectrometry. The ferulic acid content decreased from May to June, indicating that ferulic acid was utilized in early stages of cell wall formation. Monolignol glucosides were detected at early stages of lignification, whereas the contents of monolignols, coniferaldehyde, sinapaldehyde, p-coumaric acid, and ferulic acid peaked at later stages of lignification. Therefore, lignin precursors may be supplied differentially during the lignification process. In August, the rate of lignification decreased, although the contents of various lignin precursors peaked, implying that the rate-limiting step in the cessation of lignification in bamboo is transport or polymerization of lignin precursors, rather than their biosynthesis. 相似文献
302.
303.
Kato Yoshikazu Togashi Hiroyuki Kurita Yutaka Kamauchi Hiromitsu Tayasu Ichiro 《Fisheries Science》2020,86(4):615-623
Fisheries Science - To test whether stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) can be used to understand the ecological connectivity of Japanese flounder Paralichthys... 相似文献
304.
Hiroaki Matsuo Nobuyuki Matsuka Koji Omori Yoshitsugu Koizumi Ichiro Takeuchi 《Fisheries Science》2010,76(1):147-153
In order to estimate the nitrogen loading from fish aquaculture facilities, we studied the nitrogen and carbon stable isotope ratios (δ15N and δ13C, respectively) in the brown macroalga Sargassum piluliferum and small amphipod crustaceans Caprella spp., both of which are lower trophic level biota found at fish and pearl oyster aquaculture facilities situated along the eastern coast of the Uwa Sea, Japan. This coastal region is one of the least populated areas along the Japanese coast. The mean concentrations of chlorophyll a, dissolved inorganic nitrogen, dissolved inorganic phosphate, and dissolved silicate-Si were 1.5- to 2-fold higher in samples from the fish aquaculture facilities than in those from the pearl oyster aquaculture facilities, indicating that the fish aquaculture facilities were associated with nitrogen loading. The δ15N abundance level in S. piluliferum collected from the fish aquaculture facilities was significantly higher (1.3‰) than that in macroalga collected at the pearl oyster aquaculture facilities, whereas that in Caprella spp., primary consumers, was only slightly higher (0.3‰). The feeding style of Caprella spp., which depends on suspended particulate organic matter and attached microalgae, is considered to the primary causal factor for the lack of a significant difference in δ15N abundance level between the two types of aquaculture facilities. Based on these results, we conclude that S. piluliferum found in close proximity of aquaculture facilities is a suitable organism for monitoring nitrogen loading from fish aquaculture facilities, through the analysis of δ15N. 相似文献
305.
Shigenobu Namiki Hiroshige Tanaka Satoshi Katayama Osamu Funaki Ichiro Aoki Yoshioki Oozeki 《Fisheries Science》2010,76(6):951-959
In order to validate daily increment formation in otoliths of immature and adult Japanese anchovy Engraulis japonicus, three rearing experiments using chemical marking of otoliths were conducted on adult anchovy in summer 2004 and immature
anchovy in summer 2005 and in winter 2006. In the two experiments conducted in summer, the number of otolith microincrements
between alizarin complexone (ALC) marks showed that microincrements were formed daily. In the summer 2005 experiment, immature
anchovy under conditions of reduced daily food rations also showed daily microincrement formation. Average increment width
was 0.9 μm in adults and 1.8–3.1 μm in immature anchovy. In contrast, no clear increments were observed between ALC marks
on the otoliths from the experiment in winter 2006, and scanning electron microscope (SEM) observations failed to confirm
clear increment formation. We consider that low water temperatures (<13–14°C) restricted otolith growth and lowered the contrast
between the discontinuous and the incremental zones of the otolith increments. For age estimation of Japanese anchovy, clear
increments wider than about 1 μm in the otolith can be regarded as daily increments. However, daily age estimation of immature
and adult anchovy that experience low water temperatures in winter may be difficult due to the obscurity of the increments. 相似文献
306.
Ichiro?Nagano Seiko?Inoue Kenji?Kawai Syun-ichirou?OshimaEmail author 《Fisheries Science》2009,75(3):707-714
Pseudotuberculosis is a bacterial septicaemia caused by Photobacterium damselae subsp. piscicida in several marine fish species. Yellowtail Seriola quinqueradiata is the most sensitive fish species to this disease. The internal organs of naturally infected yellowtail exhibit whitish
spots, tubercle-like tissue structures, consisting of bacterial accumulations. There have been many trials for experimental
infection, however adequate method of infection that reproduces moderate mortality and primary clinical signs has not yet
established. Present investigation evaluated an immersion infection method by using logarithmic culture-phase bacteria resulting
in higher mortality than that using stationary culture-phase bacteria. Typical white spots on the spleen and kidney were also
observed constantly in dead fish. Transmission electron microscopy and fluorescent antibody microscopy showed bacterial clusters
not only in the spleen and kidney but also in the blood channels in the secondary gill filaments. These results were confirmed
repeatedly by plural experiments. The use of logarithmic-phase bacteria in immersion infection is an appropriate technique
to reproduce moderate mortality and primary clinical signs, which will be a reliable infection method also for the challenge
test of pseudotuberculosis vaccine. 相似文献
307.
为了丰富小麦功能分子标记的数量,为小麦功能基因的定位、比较基因组学、小麦起源和进化等方面的研究奠定基础。从前期利用小麦转录组数据鉴定出的8 389个EST-SSR序列中,随机选取585对引物得分大于95的标记进行分析,以川麦42和川农16杂交后自交获得的重组自交系群体为试验材料,利用新开发出的EST-SSR标记,并结合SSR标记和SRAP标记,构建了一张遗传图谱。结果表明,585对EST-SSR引物中有555对能在亲本川麦42和川农16中扩增出稳定清晰的条带,引物有效性为94.87%。其中有44对EST-SSR引物在川麦42和川农16中表现出明显的、稳定的多态性,多态性率为7.93%。所构建的遗传图谱中含有本次新开发的EST-SSR标记的连锁群共12个,由163个标记组成,包括17个EST-SSR标记,73个SSR标记和73个SRAP标记,覆盖小麦基因组长度1 551.5 cM,相邻标记之间的平均距离为13.11 cM。本研究丰富了小麦功能分子标记的数量,为小麦功能基因的定位、比较基因组学、小麦起源和进化等方面的研究奠定基础。 相似文献
308.
309.
Naofumi Morita Tomoko Maeda Megumi Miyazaki Makoto Yamamori Hideho Miura Ichiro Ohtsuka 《Cereal Chemistry》2002,79(4):491-495
The dough properties and baking qualities of a novel high‐amylose wheat flour (HAWF) and a waxy wheat flour (WWF) (both Triticum aestivum L.) were investigated by comparing them with common wheat flours. HAWF and WWF had more dietary fiber than Chinese Spring flour (CSF), a nonwaxy wheat flour. Also, HAWF contained larger amounts of lipids and proteins than WWF and CSF. There were significant differences in the amylose and amylopectin contents among all samples tested. Farinograph data showed water absorptions of HAWF and WWF were significantly higher than that of CSF, and both flours showed poorer flour qualities than CSF. The dough of WWF was weaker and less stable than that of CSF, whereas HAWF produced a harder and more viscous dough than CSF. Differential scanning calorimetry data showed that starch in HAWF dough gelatinized at a lower temperature in the baking process than the starches in doughs of WWF and CSF. The starch in a WWF suspension had a larger enthalpy of gelatinization than those in HAWF and CSF suspensions. Amylograph data showed that the WWF starch gelatinized faster and had a higher viscosity than that in CSF. The loaves made from WWF and CSF were significantly larger than the loaves made from HAWF. However, the appearance of bread baked with WWF and HAWF was inferior to the appearance of bread baked with CSF. Bread made with WWF became softer than the bread made with CSF after storage, and reheating was more effective in refreshing WWF bread than CSF bread. Moreover, clear differences in dough and bread samples were revealed by scanning electron microscopy. These differences might have some effect on dough and baking qualities. 相似文献