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141.
M. Seguchi M. Takemoto U. Mizutani M. Ozawa C. Nakamura Y. Matsumura 《Cereal Chemistry》2004,81(5):633-636
Dried egg white protein was heated at 120°C for 1 hr, added to a fresh wheat flour (protein 8.6%), and the protein and wheat flour were subjected to acetic acid (pH 3.5) fractionation. The results showed that egg white protein increased the binding between prime starch (PS) and tailings (T) fractions in wheat flour. Several conditions for heating of egg white protein were examined to determine 1) the effect of the amount of water added to the protein before heating; 2) the effect of heating time (hr) on protein at 120°C; and 3) the effect of heating temperature on the binding between PS and T fractions. The amount of protein per 50.0 g of wheat flour was further examined for the maximum binding between PS and T fractions. The heated egg white protein was analyzed by Fourier transform infrared (FT‐IR) spectroscopy, and the changes in the secondary structures (α‐helix, β‐sheets, and others) of the protein caused by heating were studied. When egg white protein was heated at 120°C for 8 hr, 9.0% of the α‐helix structures of egg white protein decreased to 3.0%, and 37.0% of the β‐sheet structures increased to 41.0%. The decrease of α‐helix and increase of β‐sheet structures of heated egg white protein were related to the increase in the binding between PS and T fractions in the same heated egg white protein and wheat flour sample. A relationship between the structural changes in heated egg white protein (180°C, 1 hr) and the binding between PS and T fractions in the heated egg white protein and wheat flour was also observed. 相似文献
142.
H Sano A Takebayashi Y Kodama K Nakamura H Ito Y Arino T Fujita H Takahashi K Ambo 《Journal of animal science》1999,77(9):2564-2573
The effects of feed restriction, cold exposure, and the initiation of feeding on blood glucose metabolism, other blood metabolites, hormones, and tissue responsiveness and sensitivity to insulin were measured in sheep. The sheep consumed orchardgrass hay ad libitum (AL) or were restricted to 82% of the ME requirement for maintenance (RE) and were exposed to a thermoneutral (20 degrees C) or a cold environment (2 degrees C). An isotope dilution method and a glucose clamp approach were applied to determine blood glucose metabolism and insulin action, respectively. Plasma NEFA and insulin concentrations were influenced by feed restriction. Concentrations of plasma glucose, NEFA, insulin, and glucagon were influenced by cold exposure. Plasma NEFA concentration for RE decreased after the initiation of feeding and plasma insulin concentration increased transiently for all treatments. [U-13C]Glucose was continuously infused for 8 or 7 h after a priming injection starting 3 h before the initiation of either feeding or insulin infusion, respectively. When responses to feeding were studied, blood glucose turnover rate was less (P < .001) for RE than for AL, and it was greater (P < .001) during cold exposure than in the thermoneutral environment. The rate changed little after the initiation of feeding. For the glucose clamp approach, insulin was infused over four sequential 1-h periods at rates from .64 to 10 mU x kg BW(-1) x min(-1), with concomitant glucose infusion to maintain preinfusion plasma glucose concentrations. The rates of glucose infusion and blood glucose turnover increased (P < .001) dose-dependently with insulin infusion rate. The maximal glucose infusion rate was greater (P < .05) for RE than for AL and was greater (P < .001) during cold exposure than in the thermoneutral environment. The plasma insulin concentration at half-maximal glucose infusion rate was lower (P < .1) during cold exposure. Blood glucose turnover rate tended to be greater (P = .10) for RE than for AL, and it was greater (P < .001) during cold exposure than in the thermoneutral environment. The ratio of endogenous production to utilization of glucose was suppressed by insulin infusion. In sheep fed a roughage diet, blood glucose turnover rate seems to be influenced by both intake level and environmental temperature, but not by the act of feeding. Moreover, the action of insulin on glucose metabolism is enhanced during cold exposure, and the effect of feed restriction is somewhat enhanced. 相似文献
143.
There is a need to develop low-cost methods for larviculture that emphasize disease prevention. We evaluated stagnant water
larviculture in flounder Paralichthys olivaceus using rotifer amictic eggs treated with glutaraldehyde. Growth and survival of the larvae were similar to in larvae reared
by standard running water larviculture with daily feeding of rotifers (control). In the experimental group, the n-3 highly
unsaturated fatty acid content of rotifers in the rearing water was higher than in the enriched rotifers fed to the control
group. We also observed a similar pattern for the fatty acid composition of flounder larvae. The viable bacterial counts associated
with rotifers in stagnant water were lower than those associated with enriched rotifers, and there were fewer bacterial genera.
However, the viable bacterial count was the same or higher in the experimental rearing water compared with that in the control
group. The α-Proteobacteria and Cytophaga–Flavobacterium–Bacteroidetes group dominated the bacterial community structure after larval hatching. To our knowledge, this is the first time that stagnant
water larviculture, using only disinfected amictic eggs, has been successfully demonstrated on a mass production scale. This
method appears to offer benefits including improved nutrition, more favorable bacterial communities, and lower cost. 相似文献
144.
Katsuyuki Hayakawa Keiko Tanaka Toshiki Nakamura Shigeru Endo Tsuguhiro Hoshino 《Cereal Chemistry》1997,74(5):576-580
The viscoelastic properties and molecular structure of the starch isolated from waxy (amylose-free) hexaploid wheat (WHW) (Triticum aestivum L.) were examined. WHW starch generally had lower gelatinization onset temperature, peak viscosity, and setback than the starch isolated from normal hexaploid wheat (NHW). Differential scanning calorimetry (DSC) showed that WHW starch had higher transition temperatures (To, Tp, and Tc) and enthalpy (ΔH) than NHW starch. However, when compared on the basis of amylopectin (AP) content, ΔH of WHW starch was almost statistically identical to that of its parental varieties. Typical A-type X-ray diffraction patterns were observed for the starches of WHW and its parental varieties. Somewhat higher crystallinity was indicated for WHW starch. WHW starch was also characterized by having greater retrogradation resistance. The high-performance size-exclusion chromatography (HPSEC) of amylopectin showed that each amylopectin yielded two fractions after debranching. Although WHW amylopectin had somewhat long B chains, little difference was observed in the ratio of Fr.III/ Fr.II between WHW and its parental varieties. 相似文献
145.
Yohei Nakamura Takuro Shibuno Nobuaki Suzuki Jun Nakamori Kiyoaki Kanashiro Yoshiro Watanabe 《Fisheries Science》2010,76(3):503-510
Molecular and otolith analyses were conducted for 173 settlement-stage larvae of emperor fishes (family Lethrinidae) collected
by light traps at Ishigaki Island, southern Japan, in July and August (summer season), to (1) present diagnostic DNA markers
for identification of lethrinid species and (2) compare the size and age at settlement of each species. PCR–RFLP and direct
nucleotide sequencing analyses identified 8 species. Size (standard length, SL) at settlement differed significantly between
species; Lethrinus ornatus (mean SL ± SD, 12.8 ± 1.5 mm), L. obsoletus (14.2 ± 0.8 mm) and L. harak (15.8 ± 1.6 mm) settled at a smaller size than L. atkinsoni (17.0 ± 1.3 mm), L. genivittatus (17.3 ± 1.0 mm), L. olivaceus (18.1 ± 0.6 mm), L. nebulosus (18.6 ± 4.2 mm), and L. sp.2 reported by Lo Galbo et al. (J Mol Evol 54:754–762, 2002) (21.7 ± 1.4 mm). Age at settlement tends to increase with
settlement size; L. obsoletus (mean age ± SD, 25.6 ± 1.2 days), L. atkinsoni (26.1 ± 2.1 days) and L. ornatus (26.3 ± 2.9 days) were younger at settlement than L. nebulosus (28.4 ± 2.1 days), L. harak (29.2 ± 1.7 days), L. olivaceus (29.5 ± 1.0 days), L. genivittatus (30.5 ± 1.7 days) and L. sp.2 (31.0 ± 2.0 days). Although our study showed interspecific variation in body size and age at settlement among 8 lethrinid
species, further seasonal replication is necessary to clarify the general patterns. 相似文献
146.
Vongvichith Bounsong Morioka Shinsuke Sugita Tsuyoshi Phousavanh Nokjalia Phetsanghanh Norkeo Chanthasone Phonaphet Pommachan Phoutsamone Nakamura Satoshi 《Fisheries Science》2020,86(1):145-151
Fisheries Science - The growth of the climbing perch Anabas testudineus reared on lower protein feeds with the replacement of fishmeal (FM) by prepupae of the black soldier fly (BSF) Hermetia... 相似文献
147.
Tanaka Tatsuya Ikeda Ryunosuke Yuta Yuta Tsurukawa Kanji Nakamura Satoshi Yamaguchi Takeharu Komeyama Kazuyoshi 《Fisheries Science》2019,85(6):1037-1043
Fisheries Science - In aquaculture, periodic measurement of fish body size is required to suitably assess growth progress. The aim of this study is to monitor the growth of free-swimming red sea... 相似文献
148.
Yohei Nakamura Masahiro Horinouchi Mitsuhiko Sano Takuro Shibuno 《Fisheries Science》2009,75(6):1401-1408
Whilst the importance of seagrass beds as nurseries for coral reef fishes has been clearly recognized, the vast majority of
early studies on fish nursery habitats emphasized the close proximity of the latter to coral reefs. To determine the potential
nursery role of isolated seagrass beds, we investigated the degree to which juvenile emperor fishes (Lethrinidae) utilized
seagrass beds in the presence/absence of adjacent coral habitats at Ishigaki Island (southern Japan), such fishes being known
to use seagrass beds as nurseries. Seagrass beds in close proximity to coral habitats (distance between the two habitats of
50–200 m) had greater densities of lethrinid juveniles than those without adjacent coral habitats (2.5–4 km) for 3 different
sites investigated, although a significant difference was obtained only for 1 site. Juveniles of Lethrinus atkinsoni, L. obsoletus, L. harak, and L. nebulosus were observed in seagrass beds with and without adjacent coral habitats, whereas L. ornatus occurred only in the former. Overall, most lethrinid juveniles utilize seagrass beds irrespective of the presence of adjacent
adult coral habitat, suggesting that both types of seagrass beds would contribute to lethrinid adult populations. Therefore,
management efforts for lethrinid populations should be applied not only to contiguous coral-seagrass habitat systems but also
to isolated habitats. 相似文献
149.
Tomoko Suzuki Shougo Nishimura Kazuhiro Yagi Ryousuke Nakamura Yoshihiro Takikawa Yoshinori Matsuda Koji Kakutani Teruo Nonomura 《Phytoparasitica》2018,46(1):31-43
The lengths of conidiophores in fungal colonies of the melon powdery mildew pathogen Podosphaera xanthii Pollacci KMP-6 N cultured under greenhouse (natural) conditions differed markedly from those cultured in a growth chamber. We hypothesized that light wavelength was responsible for the differences in conidiophore length. In this study, we examined the effects of light-emitting diode (LED) irradiation (purple, blue, green, orange, and red light) and white light on colony development and conidiophore formation in KMP-6 N using a stereomicroscope and a high-fidelity digital microscope. Colonies on leaves were flat under greenhouse conditions and under red LED light irradiation but were stacked under growth chamber conditions and under purple, blue, green, and orange LED light irradiation. In addition, KMP-6 N formed catenated conidia comprising six conidia per conidiophore under greenhouse conditions and red light but more than seven conidia per conidiophore under growth chamber conditions and purple, blue, green, and orange light. Furthermore, almost none of the conidia on top of the conidiophores grown under blue light were fully constricted. Therefore, these fungi could not scatter their conidia and spread infection. This is the first report of the effects of LED lights on conidiophore formation in the melon powdery mildew fungus P. xanthii. The results provide insight into the mechanisms underlying the responses of conidiophores to light of specific wavelengths and conidial scatter from conidiophores of melon powdery mildew fungi. 相似文献