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371.
Yuchengmin Zhang Hideto Tsutsui Nobuhiro Yamawaki Yasuhiro Morii Gregory N. Nishihara Shiro Itoi Osamu Arakawa Tomohiro Takatani 《Marine drugs》2021,19(12)
Toxic crabs of the family Xanthidae contain saxitoxins (STXs) and/or tetrodotoxin (TTX), but the toxin ratio differs depending on their habitat. In the present study, to clarify within reef variations in the toxin profile of xanthid crabs, we collected specimens of the toxic xanthid crab Zosimus aeneus and their sampling location within a single reef (Yoshihara reef) on Ishigaki Island, Okinawa Prefecture, Japan, in 2018 and 2019. The STXs/TTX content within the appendages and viscera or stomach contents of each specimen was determined by instrumental analyses. Our findings revealed the existence of three zones in Yoshihara reef; one in which many individuals accumulate extremely high concentrations of STXs (northwestern part of the reef; NW zone), another in which individuals generally have small amounts of TTX but little STXs (central part of the reef; CTR zone), and a third in which individuals generally exhibit intermediate characteristics (southeastern part of the reef; SE zone). Furthermore, light microscopic observations of the stomach contents of crab specimens collected from the NW and CTR zones revealed that ascidian spicules of the genus Lissoclinum were dominant in the NW zone, whereas those of the genus Trididemnum were dominant in the CTR zone. Although the toxicity of these ascidians is unknown, Lissoclinum ascidians are considered good candidate source organisms of STXs harbored by toxic xanthid crabs. 相似文献
372.
Positional distribution of fatty acids in triacyl-sn-glycerols (TAG) of the flathead flounder Hippoglossoides dubius has been reinvestigated in order to accurately determine the contents of tetracosahexaenoic acid (24:6n-3) in the sn-1, sn-2, and sn-3 positions. Flesh TAG obtained from three flounders were subjected to stereospecific analysis using a suitable procedure
for fish TAG analysis. The 24:6n-3 acid was found in the three positions at the concentrations of 0.3–5.5 mole% (the sn-1 position), 1.6–23.3 mole% (the sn-2 position), and 0.6–8.9 mole% (the sn-3 position). In contrast to a previous analysis, the present analysis revealed that 24:6n-3 is preferentially esterified
in the sn-2 position followed by the sn-3 and sn-1 positions. Other polyunsaturated fatty acids, docosahexaenoic acid (22:6n-3; DHA) and docosapentaenoic acid (22:5n-3; DPA),
showed a similar distribution pattern. These results indicate that the general tendency observed for long-chain polyunsaturated
fatty acids in marine fish TAG can be extended to the distribution of 24:6n-3 in flathead flounder TAG. Because the use of
flathead flounders is entirely for human food, we thus intake 24:6n-3 concentrated in the sn-2 position of their TAG. 相似文献
373.
Tomoaki NII Md Zahorul ISLAM Satoru KAKE Mitsuya SHIRAISHI Takashi TAKEUCHI Hidefumi KUWATA Atsushi MIYAMOTO Etsumori HARADA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(11):1499
Bovine lactoferrin (BLF) reportedly lowers blood pressure and induces vasorelaxation, but its effect on nitric oxide (NO) production has not been established. Accordingly, we aimed to determine whether BLF induces NO production in bovine aortic endothelial cells, and the effects of extracellular free magnesium (Mg) ion concentrations on this NO production. BLF induced NO production time-dependently. NO production was markedly inhibited by the NO synthase inhibitor, NG-nitro-L-arginine methyl ester, in an effect abolished by L-arginine, but not D-arginine. NO production was suppressed at low concentrations, and enhanced at high concentrations, of Mg ions in culture medium. These results suggest that BLF has an important role in hypotensive effects. Mg ions may affect BLF-induced NO production. 相似文献
374.
375.
Seed exudates collected from three cultivars (cv. Hokkaikintoki, Himetebou, and Kurodane-kinugasa) of common bean ( Phaseolus vulgaris L.) were fractionated based on several physicochemical properties, and the nutrient substances in the fractions effective for Rhizobium proliferation were determined. Regardless of the common bean cultivars, the low molecular weight and high polarity fraction showed the most beneficial effect on Rhizobium proliferation. After further separation of the low molecular weight and high polarity fraction, the promoting effect was detected in the non-ionic and the cationic plus ampho-teric subtractions. Although the amount of sugars or amino acids exuded from a seed was, respectively, similar in all the cultivars except for the sugars in Kurodanekinugasa, the content of these compounds per seed-weight was inversely proportional to the seed size. Ten sugars and twenty-one amino acids were, respectively, identified in the non-ionic and cat-ionic plus amphoteric subtractions, and there were some differences in the composition of these substances between common bean cultivars. 相似文献
376.
Miyuki Iizuka Yasuhiro Arima Tadashi Yokoyama Koichiro Watanabe 《Soil Science and Plant Nutrition》2013,59(2):219-225
Sufficient rhizobium population in the rhizosphere of legume seedlings is required for early and enough setting of root nodules. Potential of seed and seedling root exudates for proliferation of Bradyrhizobium japonicum PNT119 was evaluated in the soybean cvs. Enrei and Tachinagaha. In both cultivars, seed exudates showed a higher potential than root exudates. In the seed exudates, a low-molecular high-polarity fraction including sugars and amino acids showed a higher potential than both high-molecular fraction and low-molecular low-polarity fraction. The correlations between the sugar or amino acid contents of seed exudates and the number of root nodule primordia at 7 d after sowing were investigated among 12 soybean cultivars. When seeds were inoculated with a low rhizobium density, a high correlation coefficient was detected between them. However, there was no positive correlation in the plants inoculated with a high rhizobium density. These results suggest that the amount of low molecular substances in the seed exudates determines the number of root nodule primordia through rhizobium proliferation around seed and young roots when the rhizobium density is the limiting factor. The genetic trait relating to seed coat secretion should be considered as a possible key factor contributing to adequate root nodulation in soybean seedlings cultivated in fields with a low rhizobium density. 相似文献
377.
Wakako Taira Yasuhiro Funatsu Masataka Satomi Takashi Takano Hiroki Abe 《Fisheries Science》2007,73(4):913-923
To make use of underutilized fish species and produce high-quality condiments substitutable for those of mammalian origin,
fish sauces were produced on a small industrial scale from three fish species, the flyingfish Cypselurus agoo agoo, the small dolphinfish Coryphaena hippurus, and the deepsea smelt Glossanodon semifasciatus, using salt and koji mold. During 180 days of fermentation, the pH decreased to approximately 4.5 and total nitrogen and free amino acids increased
to approximately 2 g/100 mL and 6000 mg/100 mL, respectively. Halophilic and extreme halophilic bacterial counts dramatically
increased from 106 to 108 colony forming units/mL between days 14 and 30 and decreased the reafter. In the final products, the pH and salt concentration
decreased to between soy sauce and a Vietnamese fish sauce, Nuoc mam. The total amino acid and organic acid contents were almost the same as those of Nuoc mam and soy sauce. Sensory evaluation found these products to have lower smell, saltiness, and bitterness, and higher sweetness
and umami taste than Nuoc mam. During fermentation, the histamine content increased in one or two of three fermentation tanks for each fish species. As
a result, the histamine content of the final products was higher than that in Nuoc mam. 相似文献
378.
This article reports the concentration and composition of the isomers of cis-icosenoic acid (20:1) in the fatty acids of various species of Japanese marine animals. The main purpose of this study is to reveal the distribution of a positional isomer, cis-7-20:1 (c7-20:1), in marine animals. Because this isomer overlaps with the c9-20:1 isomer in gas chromatography (GC) on the commonly used polar capillary columns, less information is available on its occurrence and distribution. In this study, the monounsaturated fatty acids isolated by argentation thin-layer chromatography were analyzed by GC using a highly polar capillary column, SLB-IL111 (100 m long), with the highest polarity among the commercially available GC columns. A clear separation between the c7-20:1 and c9-20:1 isomers enabled the analysis of all the isomers of 20:1 present in marine animals. The results confirmed that the c7 isomer was a minor component in the 20:1 in the pelagic fish, which is rich in the c9 and/or c11 isomers as reported previously. In contrast, the c7 isomer was one of the major isomers in flatfish, shellfish, crabs, and brittle stars. In these samples, the c13 isomer also occurred at higher concentrations rather than the c9 isomer. Because such a specific pattern of the 20:1 positional isomers was generally observed in both benthic fish and its dietary animals, the c7 isomer in the benthic fish probably originated from its diet. These marine animals are used as food in Japan, and therefore the c7-20:1 isomer is consumed by humans. 相似文献
379.
Yasuhiro Suzuki Yoshio Sano Tetsuya Ishikawa Tomoko Sasaki Ushio Matsukura Hiro‐Yuki Hirano 《Cereal Chemistry》2003,80(2):184-187
The effects of environmental temperature (21 vs. 28°C) during rice seed development on the starch characteristics (apparent amylose content, amylopectin chain length distribution, and gelatinization properties) of nonwaxy Taichung 65 (T65), waxy Taichung (T65wx), du2‐2 mutated low‐amylose strain Taichung (76‐3/T65), and Koshihikari were studied. Amylose contents increased with decreasing environmental temperatures. Analysis of the amylopectin chain length distribution showed that the relative amounts of long chains with degree of polymerization (DP) > 25 in all starches decreased if maturation occurred at 21°C. Gelatinization onset, peak, and conclusion temperatures and enthalpies decreased with decreasing environmental temperatures. Of all starches studied, the du2‐2 mutated low‐amylose Taichung (76‐3/T65) was most affected by maturation temperatures. These results indicate that the du2‐2 mutated low‐amylose Taichung (76‐3/T65) may be a useful strain in understanding biochemical and genetic starch biosynthesis response to slight changes in temperature. 相似文献
380.
Sayaka Sogawa Kiyotaka Hidaka Yasuhiro Kamimura Masanori Takahashi Hiroaki Saito Yuji Okazaki Yugo Shimizu Takashi Setou 《Fisheries Oceanography》2019,28(4):454-467
The sustainable use of marine resources requires understanding the surrounding ecosystem and elucidating mechanisms of variation. However, we still lack a comprehensive understanding of environmental variation in the spawning and nursery grounds of important fisheries species Japanese sardine (Sardinops melanostictus) and mackerels (Scomber japonicus and Scomber australasicus) in the northwest Pacific. Here, we investigate detailed physical, chemical, and biological environment variations in the spawning and nursery grounds along the Kuroshio and Kuroshio Extension area from intensive investigation in spawning season (April) of 2013. We found similar water mass property and copepod community in the egg‐rich Kuroshio area and the larvae‐rich downstream Kuroshio Extension area, indicating environmental variability is small during transportation and development processes. The egg‐rich northern Izu Islands region showed high copepod abundance, although low nutrient and chlorophyll concentrations were observed. Eggs were scarce or absent in the second survey 10 days after abundant eggs were observed in the region, along with differences in water property and copepod community. This indicates that not only the location but also the specific water characteristic and copepod community are a determining factor for spawning. Indicator communities of copepod found in our study (indicator community of transportation process from spawning ground, of non‐spawning ground, and of reproductive area in the Kuroshio Extension area) would be a key factor for recruitment prediction. 相似文献