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21.
The foam stability of beer is one of the important key factors in evaluating the quality of beer. The purpose of this study was to investigate the relationship between the level of malt modification (degradation of protein, starch, and so on) and the beer foam stability. This was achieved by examining foam-promoting proteins using two-dimensional gel electrophoresis (2DE). We found that the foam stability of beer samples brewed from the barley malts of cultivars B and C decreased as the level of malt modification increased; however, the foam stability of cultivar A did not change. To identify the property providing the increased foam stability of cultivar A, we analyzed beer proteins using 2DE. We analyzed three fractions that could contain beer foam-promoting proteins, namely, beer whole proteins, salt-precipitated proteins, and the proteins concentrated from beer foam. As a result, we found that in cultivar A, some protein spots did not change in any of these three protein fractions even when the level of malt modification increased, although the corresponding protein spots in cultivars B and C decreased. We analyzed these protein spots by peptide mass finger printing using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. As a result, all of these spots were identified as barley dimeric alpha-amylase inhibitor-I (BDAI-I). These results suggest that BDAI-I is an important contributor to beer foam stability.  相似文献   
22.
The development of a closed recirculating aquaculture system that does not discharge effluents would reduce a large amount of pollutant load on aquatic bodies. In this study, eel were reared in a closed recirculating system, which consisted of a rearing tank, a foam separation unit, a nitrification unit and a denitrification unit. The foam separation unit has an inhalation-type aerator and supplies air bubbles to the rearing water. The growth of eel, which were fed a commercial diet, was satisfactory, with gross weight increases of up three times in 3 months. The survival rate under the congested experimental conditions was 91%. The foam separation unit maintained oxygen saturation in the rearing water at about 80%. Furthermore, fine colloidal substances were absorbed on the stable foam formed from eel mucus and were removed from the rearing water by foam separation. Ammonia oxidation and the removal of suspended solids were accomplished rapidly and simultaneously in the nitrification unit. The ammonia concentration and turbidity were kept at less than 1.2 mg of N per litre and 2.5 units, respectively. When the denitrification process was operated, nitrate that accumulated in the rearing water (151 mg of N per litre) was reduced to 40 mg of N per litre. The sludge was easily recovered from the nitrification and denitrification tanks, and the components were found suitable as compost. Based on these results, the intensive aquaculture of freshwater fish such as eel can be achieved using a closed recirculating system without emission.  相似文献   
23.
International Aquatic Research - Shrimp muscle contains taste component compounds, such as glutamic acid and inosinic acid (IMP). When both are present, taste intensity increases by fourfold to...  相似文献   
24.
Angiotensin-I-converting enzyme (ACE) plays a crucial role in the crisis of hypertension. Some peptides that originate from protease hydrolysates are known to suppress ACE activity in vitro and in vivo. Here, we investigated whether trypsin hydrolysate of oyster Crassostrea gigas showed hypotensive activity and ACE inhibition. The hydrolysate significantly suppressed systolic blood pressure and ACE activity in spontaneously hypertensive rats following a one-shot oral administration and a long-term feeding experiment lasting 9 weeks. Each hydrolysate from oyster tissue showed ACE inhibitory activity, indicating the hypotensive effect was due to synergism. One potent ACE inhibitory peptide, Asp-Leu-Thr-Asp-Tyr, was identified from the hydrolysate of the striate muscle, and the peptide exhibited hypotensive activity in vivo. Protease digestion analysis suggested that Asp-Tyr could be the real effector of this penta-peptide in vivo.  相似文献   
25.
26.
Chromogranin A (CgA) is an acidic glycoprotein that is co-stored with hormones or neurotransmitters in granular components of endocrine cells and neurons, and released together with them in response to adequate stimulation. In addition to acting as a packaging protein, CgA functions as a precursor molecule that yields several bioactive peptides by proteolytic cleavage. The purpose of this study is to elucidate how different the processing of CgA is among endocrine tissues by immunostaining using multiple region-specific antisera, and to evaluate the availability of region-specific antisera. When various endocrine organs of rats were immunostained with four region-specific antisera against rat CgA (CgA 1-28, 94-130, 296-314, and 359-389), all amine/peptide-secreting endocrine tissues except the pineal body were stained positively. The adrenal medulla and gastric endocrine cells were equally intensely immunoreactive to all four antisera, while the other endocrine tissues, represented by pancreatic islets, showed different staining patterns depending on the antiserum. These results suggest that the processing of CgA differs from tissue to tissue. An antiserum against horse CgA 335-365, corresponding to rat CgA 359-389 which shows the highest concentration in the plasma and urine of the rat, again stained all endocrine tissues of the horse except the pineal body. Therefore, the anti-horse CgA 335-365 serum is useful for immunohistochemical survey of horse CgA, and may make possible the establishment of a CgA assay system for the measurement of CgA in the plasma, urine and saliva.  相似文献   
27.
Abstract: Blood samples were collected from 29 juvenile red pacu ( Piaractus brachypomus ), ornamental freshwater fish, to establish baseline blood chemistry values. Mean (minimum-maximum) values, obtained by automated bichromatic analysis and ion selective electrode analysis, were as follows: sodium, 150.4 (146–159) mmol/L; potassium, 3.93 (2.7–5.0) mmol/L; chloride, 138.7 (128–150) mmol/L; total CO2, 7.5 (6–10) mmol/L; albumin, 0.86 (0.5–1.0) g/dL; lactate dehydrogenase, 237.8 (65–692) IU/L; aspartate aminotransferase, 49.1 (0–125) IU/L; creatinine, 0.31 (0.2–0.4) mg/dL; calcium, 10.80 (9.5–12.5) mg/dL; anion gap, 6.89 (1.2–12.5) mmol/L; and phosphorus, 7.29 (4.1–8.9) mg/dL.  相似文献   
28.
The usefulness of magnetic resonance (MR) is already established, but it has a disadvantage of requiring a long scanning time. A short-time examination is more or less needed so as to be more practical in veterinary clinics. A protocol of the short-time MR examination was devised based on parameters determined, and validity of the protocol was assessed through the diagnosis of clinical cases with intervertebral disc diseases. With this protocol, it was possible to complete an MR examination for the spine within 15 min. The MR images and myelographic findings were correlated well in this study, suggesting the short-time protocol of MR examination can be used in the clinical diagnosis of spinal diseases.  相似文献   
29.
The rapid growth and high survival rate of Erysipelothrix rhusiopathiae was determined using a culture of the bacterium in tryptic soy broth supplemented with 0.3% Tris-hydroxymethyl aminomethane and 0.1% Tween 80 (TT-TS broth). High concentrations of 64, 66 and 43 kDa proteins, which are associated with protection against E. rhusiopathiae infection in mice, were obtained by alkaline treatment of whole cells using 0.05-1 N NaOH. The supernatant of alkaline treated cells (alkaline extract; AE) was stable at alkaline or neutral pH. However, aggregates appeared at neutral pH in the absence of sodium dodecyl sulphate (SDS). A high yield of 64, 66 and 43 kDa proteins was obtained from strain Agata (serovar 5). The proteins were eluted from gel bands following SDS-polyacrylamide gel electrophoresis (SDS-PAGE) of the AE from strain Agata and designated P64 and P43. The amounts of P64 and P43 isolated were 0.7 and 0.3 mg/16 g of wet bacteria, respectively. In a mouse protection test, 50% protective doses (PD50) of P64 and P43 were 0.58 and 0.63 microgram, respectively. Upon Western blotting of the AE, both anti-P64 and anti-P43 antibodies reacted with the 64 and 43 kDa proteins. From these results, it is suggested that P64 is the most effective protective antigen and that P43 (43 kDa protein) is a degradation product of P64. Therefore, the 64 kDa structural proteins are associated with the induction of a protective activity against E. rhusiopathiae infection in mice.  相似文献   
30.
Lymphoma was seen in an 11-year-old female savanna monkey (Ceropithecus aethiops). The superficial inguinal and visceral lymph nodes were markedly enlarged, and their architecture was completely effaced by neoplastic cells. The neoplastic cells, which were highly pleomorphic, resembled those in adult T-cell lymphoma-leukemia in humans. Ultrastructurally the neoplastic cells were characterized by nuclear irregularity and clustered dense bodies, and almost all cells showed positivity for CD3. The animal had been reared with her family, and her mother and 2 brothers had antibodies reactive to human T-cell leukemia virus. This virus serologically cross-reacts with simian T-cell leukemia virus, which may be the causative agent of the present neoplasm.  相似文献   
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