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排序方式: 共有360条查询结果,搜索用时 15 毫秒
41.
Ogawa K Sakakibara H Iwata R Ishii T Sato T Goda T Shimoi K Kumazawa S 《Journal of agricultural and food chemistry》2008,56(12):4457-4462
The anthocyanin composition and antioxidant activity of the crowberry ( Empetrum nigrum) were studied. High-performance liquid chromatography (HPLC) combined with a diode array detector and electrospray ionization mass spectrometry were used for identification and quantification of individual anthocyanins. Freeze-dried crowberry powder was extracted with 80% methanol containing 0.5% acetic acid and subjected to HPLC. Thirteen kinds of anthocyanins were identified. The major anthocyanins were cyanidin-3-galactoside and delphinidin-3-galactoside, at 8.04 and 8.62 mg/g extract, respectively. The HPLC profile of crowberry extract was similar to bilberry and blueberry. The total content of anthocyanins in crowberry was 41.8 mg/g extract, higher than the other nine major berry species (2.5-38.8 mg/g extract). The antioxidant activity was also evaluated using the 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azinobis(3-ethybenzothiazoline-6-sulfonic acid) radical quenching assays and the ferric reducing activity power assy. Crowberry extract exerted the strongest antioxidant activity. In conclusion, individual anthocyanins in crowberry were identified and then quantified in this study. Additionally, crowberry is suggested to be associated with a reduction in the risk of developing chronic diseases because of its strong antioxidant activity. 相似文献
42.
Tsutomu Ikeda Yoichi Tomimura Kengo Magara Mitsuro Ishihara Shuji Hosoya 《Journal of Wood Science》1999,45(5):417-424
To investigate the bleaching mechanism, a lignincarbohydrate complex (LCC) model compound, a vinyl ether-type lignin model dimer, and a hexeneuronic acid model compound were treated with dilute sulfuric acid of different pHs. Beech kraft pulp and red pine kraft pulp were also treated with dilute sulfuric acid and then extracted with aqueous alkali. The amount of hexeneuronic acid degradation products in acid effluents and lignin dissolved in alkali effluents were determined. It was found that the benzyl ether-type LCC bond and the vinyl ether bond in lignin were effectively cleaved under the pH where sulfuric acid bleaching of kraft pulp was effective. Hexeneuronic acid group was also effectively degraded during sulfuric acid bleaching. In beech kraft pulp bleaching, both lignin removal and hexeneuronic acid removal contributed to the kappa number reduction. In red pine bleaching, the contribution of hexeneuronic acid removal was negligible, and most of the kappa number reduction was achieved by the lignin removal.Part of this report was presented at the 9th International Symposium on Wood and Pulping Chemistry, Montreal, July 1997 相似文献
43.
Pavarot Noranarttragoon Yuji Ueda Tsutomu Hattori Takashi Matsuishi 《Fisheries Science》2011,77(4):497-502
The yield-per-recruit (YPR) analysis has been used to assess growth overfishing of exploited fish stocks. Since the ex-vessel
price per weight widely depends on the size of the fish, the result of the YPR does not imply the revenue. The value-per-recruit
(VPR) analysis, which is an economic expansion of the YPR analysis, was conducted for bighand thornyhead Sebastolobus macrochir caught off the Pacific coast of northern Honshu, Japan. The results showed that, for the current age at first capture (t
c = 3), the current fishing mortality (F = 0.12) was close to the optimum level. However, for the current F, optimum t
c in the VPR model was 8 years and would lead to a 47% increase compared to the current revenue. The maximum YPR was obtained
at t
c = 6 years, but the revenue at t
c = 6 only gave a 20% increase in the maximum revenue. The difference was caused by the size dependency of the ex-vessel price
per weight. The VPR model would generate fisheries management plans with both economical and biological consideration and
would help in making general consensus of fisheries management strategies. 相似文献
44.
45.
Takayuki Arazoe Shigeru Kuwata Tsutomu Arie Shuichi Ohsato 《Journal of General Plant Pathology》2014,80(2):153-157
To provide experimental evidence that somatic homologous recombination (HR) is involved in the instability and diversification of the avirulence gene Avr-Pita in Pyricularia oryzae, we generated a dysfunctional Avr-Pita homolog and integrated it into strain Hoku-1 containing Avr-Pita. In the transformants, the occurrence of somatic HR events between Avr-Pita and the dysfunctional homolog was confirmed by PCR–RFLP. Germlings from conidia from the HR-positive transformants had lost the avirulence function, which enabled it to infect rice cultivar Yashiromochi containing the corresponding resistant gene Pi-ta. These results suggested that genetic mutation caused by somatic HR is one of the mechanisms responsible for virulence diversity. 相似文献
46.
Characterization of plant-derived water extractable organic matter by multiple spectroscopic techniques 总被引:1,自引:0,他引:1
Zhongqi He Jingdong Mao C. Wayne Honeycutt Tsutomu Ohno James F. Hunt Barbara J. Cade-Menun 《Biology and Fertility of Soils》2009,45(6):609-616
Water extractable organic matter (WEOM) derived from fresh- or early-stage decomposing soil amendment materials may play an
important role in the process of organic matter accumulation. In this study, eight WEOM samples extracted with a 40:1 (v/w) water to sample ratio from alfalfa (Medicago sativa L.), corn (Zea mays L.), crimson clover (Trifolium incarnatum L.), hairy vetch (Vicia villosa L.), lupin (Lupinus albus L.), soybean (Glycine max L. Merr.), wheat (Triticum aestivum L.), and dairy manure were investigated using ultraviolet (UV)–visible, Fourier transform infrared (FT-IR), solution 31P nuclear magnetic resonance (NMR), and solid state 13C NMR spectroscopies. UV–visible and FT-IR spectra of the plant-derived WEOM samples were typical for natural organic matter,
but possessed less humic-like characteristics than dairy manure-derived WEOM. Solution 31P NMR spectra indicated that WEOM samples extracted from alfalfa, corn, and soybean shoots contained both orthophosphate and
monoester P. Of the monoester P in WEOM from soybean shoot, 70% was phytate P. WEOM from crimson clover, hairy vetch, lupin,
and wheat shoots contained orthophosphate only. The solid-state 13C NMR spectra of the seven plant-derived WEOM samples indicated that they all were primarily composed of sugars, amino acids
or peptides, and low molecular mass carboxylic acids. Carbohydrates were dominant components with very few aromatics present
in these samples. In addition, WEOM from crimson clover and lupin, but not other three leguminous plant WEOM samples, contained
significant asparagine. On the other hand, WEOM from corn and wheat contained less amino acids or peptides. The spectra of
WEOM of dairy manure revealed the presence of significant amounts of nonprotonated carbons and lignin residues, suggesting
humification of the manure-derived WEOM. Significant carbohydrates as well as aromatics were present in this WEOM. The P and
C bonding information for these WEOM samples may be useful for understanding the effects of WEOM on soil nutrient availability
to plants.
Trade or manufacturers' names mentioned in the paper are for information only and do not constitute endorsement, recommendation,
or exclusion by the USDA-ARS. 相似文献
47.
Studies on the neuroregulatory mechanisms on the secretion of anterior pituitary (AP) hormones in domestic animals are important because nearly all complex physiological and metabolic processes are regulated by the AP hormones. To examine them, this article considers in vivo approaches such as the techniques of intrahypothalamic injection, intracerebroventricular injection, push-pull perfusion, and microdialysis, which have been employed in our own research group for the study in cattle. Also, in vitro approaches such as bovine AP cell culture and the AP explants superfusion system are described. This article clarifies the potential of neuroendocrine study techniques in cattle. 相似文献
48.
Ikue Murata Sigefumi Saruki Katsuyoshi Kubota Sachiko Inoue Naoaki Tashiro Tsutomu Enoki Yasuhiro Utsumi Susumu Inoue 《Journal of Forest Research》2009,14(5):296-301
Effects of sika deer (Cervus nippon) and dwarf bamboo (“sasa;” Sasamorpha borealis) on seedling emergence and survival were investigated in cool-temperate mixed forests in the Kyushu mountain range, Japan.
We compared the effects of sika deer between two sites with different sika deer densities. One site (no-sasa forest) has sparse
cover of S. borealis and a high density of sika deer, and the other site (sasa forest) has dense cover of S. borealis with a low density of sika deer. In the no-sasa forest, more seedlings emerged and the survival rate of the seedlings was
higher compared with the sasa forest. Compared with the sasa forest, the canopy in the no-sasa forest was more open, the organic
layer was shallower and drier, the mean daily soil temperature was higher, and soil temperature fluctuated more widely. Those
environmental parameters did not differ between unfenced and fenced plots. The comparison between the sasa and no-sasa forests
suggested that removal of S. borealis by sika deer had an indirect positive effect on seedling emergence and survival. However, the fenced-plot experiments indicated
that sika deer inhibited seedling emergence and survival. These contradictory conclusions could result from the much larger
negative effects of S. borealis on seedling emergence and survival compared with the effects of sika deer browsing. 相似文献
49.
Tomomi BAN‐TOKUDA Carole DELAVAUD Yves CHILLIARD Tsutomu FUJIHARA 《Animal Science Journal》2010,81(6):648-656
This experiment was conducted to investigate the difference between ruminal (solid feed, SF) and abomasal (liquid feed, LF) feeding on the plasma leptin concentration in sheep. The experiment consisted of 2 weeks to adapt the animals to SF, 4 weeks of feeding on SF, 2 weeks adaptation to LF, 8 weeks of feeding on LF, 2 weeks of adaptation to SF, and 4 weeks of feeding on SF. The LF directory flowed into the abomasums of sheep by bottle feeding. Plasma leptin concentration before morning feeding was almost constant in the SF periods, whereas it showed between‐day variations when measured during the LF periods. Mean plasma leptin levels were higher for LF (7.77 ± 0.76 ng/mL; mean ± SE) than for SF periods (3.95 ± 0.16 ng/mL; mean ± SE). Although plasma leptin concentration did not show any change after feeding in the SF and LF periods, plasma insulin and glucose levels increased within 15 min after liquid abomasal feeding, but not after solid ruminal feeding. The high plasma leptin concentration during the LF periods in weaned sheep could be due to change of digestible energy intake and changes in plasma insulin and glucose levels accompanying the changes in digestive processes and nutrient supply. 相似文献
50.
Etsuko KASUYA Ken‐ichi YAYOU Tsutomu HASHIZUME Sayuki KITAGAWA Madoka SUTOH 《Animal Science Journal》2010,81(3):345-351
To clarify the role of serotonin (5‐HT) in the regulatory mechanism of L‐tryptophan (TRP)‐induced growth hormone (GH) secretion in cattle, changes in 5‐HT concentrations in the cerebrospinal fluid (CSF) in the third ventricle (3V) and GH in plasma before and after the peripheral infusion of TRP were determined simultaneously. The direct effect of TRP on GH release from the dispersed anterior pituitary cells was also assessed. A chronic cannula was placed in 3V by stereotaxic surgery, then CSF and blood were withdrawn under physiological conditions. TRP (38.5 mg/kg BW) was infused through an intravenous catheter from 12.00 to 14.00 hours and CSF and blood sampling were performed from 11.00 to 18.00 hours at 1‐h intervals. The concentration of 5‐HT in CSF was determined by high‐performance liquid chromatography with electrochemical detection. GH, melatonin (MEL), and cortisol (CORT) concentrations were measured by radio‐immunoassay and enzyme‐immunoassay. Concentrations of 5‐HT were increased by TRP infusion. The TRP infusion significantly increased GH release. On the other hand, TRP did not stimulate GH release from the bovine pituitary cells. MEL and CORT concentrations were not altered by TRP infusion. These results suggest that TRP induced GH release via the activation of serotonergic neurons in cattle. 相似文献