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21.
We used various kinds of wasted tea leaves to develop composite sheets with antibacterial properties. Antibacterial tests showed that the number of viable bacterial cells for the sheet containing wasted green tea leaves was around 10:6–107 CFU/ml after 18 h culture compared to 108 CFU/ml for a tea-free sheet. This indicates that cell growth was signifi cantly inhibited. For sheets containing other types of tea leaves (oolong, black, hojicha, and pu-erh), living cells were not found, indicating that these sheets had superior antibacterial effects. Living cells were also not found in sheets containing wasted black tea leaves or roasted tea leaves at a concentration of 60% by weight after 6 h cultivation. Therefore, roasting treatment of wasted green tea leaves was examined to improve the antibacterial activity of the sheet. In particular, the focus was on structural conversion of catechins by heating.  相似文献   
22.
Ethylene formation from ethyl moiety of ethionine   总被引:2,自引:0,他引:2  
In plants, ethylene is formed in the presence of light and flavin mononucleotide from ethionine and S-ethylcysteine. The ethylene is formed from the ethyl moiety of ethionine.  相似文献   
23.
The microscopic mechanism of the matching effect in a superconductor, which manifested itself as the production of peaks or cusps in the critical current at specific values of the applied magnetic field, was investigated with Lorentz microscopy to allow direct observation of the behavior of vortices in a niobium thin film having a regular array of artificial defects. Vortices were observed to form regular and consequently rigid lattices at the matching magnetic field, at its multiples, and at its fractions. The dynamic observation furthermore revealed that vortices were most difficult to move at the matching field, whereas excess vortices moved easily.  相似文献   
24.
The stepwise hot water extraction of soybeans, which were extractions in a series of procedures of whole soybean seeds, dehulled and sliced ones, and pressed ones carried out by autoclaving, was investigated to study the localization in the seed and their characteristics. The characteristics of each extraction were studied by HPLC, SDS-PAGE, components analysis, microscopic observation, and effect for some enzymes. Carbohydrates were easier to extract than protein. In the extractions, the ratio of uronic acid per total sugar was constantly about 0.3. A comparison of these extracts, soybean milk, extraction from defatted soybean meal, and soybean milk residues was also carried out, and the characteristics and the localization were investigated. Mid-sized proteins in soybean milk were easy to extract. However, hardly any high molecular weight proteins or high molecular weight carbohydrates were extracted. The proteins and carbohydrates were considered to be localized in the middle lamella and in the protein and/or oil bodies of the cell, and the proteins and carbohydrates were gradually extracted through seed and cell breaking. Gelation was observed only in the boiled extracts from whole seeds. Pepsin and trypsin digests of the high molecular weight protein had inhibitory activity against the angiotensin I converting enzyme.  相似文献   
25.
DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging reactions of protocatechuic and gallic acids, and their methyl esters, have been investigated by NMR. In acetone, methyl protocatechuate was gradually converted to a Diels-Alder adduct of two molecules of the intermediate quinone in the reaction with DPPH radical, whereas methyl gallate rapidly gave a symmetrical dimer via a putative quinone precursor. Both dimers are rather unstable and their structures have been deduced by in situ NMR measurements of the reaction mixtures. Gallic acid also gave a corresponding symmetrical dimer in the same reaction as methyl gallate, although protocatechuquinone produced from protocatechuic acid did not yield a Diels-Alder adduct, unlike its methyl ester. Interestingly, these dimer formations were not observed in methanol solution.  相似文献   
26.
Northwesterly cold winds characteristic of the East Asian Winter Monsoon (EAWM) dictate winter climatic conditions over the Japanese Archipelago. Japanese temperate bass Lateolabrax japonicus is a commercially important coastal fish that spawns offshore in winter and uses shallow waters as nursery habitats. To investigate the effects of EAWM on the planktonic period of L. japonicus, eggs, larvae, and juveniles were quantitatively collected in Tango Bay on the Sea of Japan side in winter and spring from 2007 to 2017. Although eggs occurred close to the mouth of the bay, planktonic larvae occurred further inside as they developed. The horizontal distribution of planktonic larvae, combined with water velocity data obtained from mooring observations, indicated that planktonic larvae are transported south‐ to westward through Ekman current and an anticyclonic circulation, which are driven by northwesterly winds. To evaluate survival during the planktonic period in each year class, the abundance of benthic larvae/juveniles was divided by winter total landings of Lateolabrax spp. (proxy of the spawning stock size). This survival index exhibited a positive correlation with the northwesterly component of winter winds, and a negative correlation with winter air temperature (average from December to February, Spearman's correlation, p < .05). There was, however, no significant correlation with winter water temperature or winter freshwater discharge in the bay. We conclude that northwesterly cold winds of EAWM play a critical role in transporting L. japonicus eggs and larvae toward nursery habitats, specifically beaches and estuaries fringing the innermost part of Tango Bay.  相似文献   
27.
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   
28.
Halocynthiaxanthin is an acetylenic carotenoid mainly found in Halocynthia roretzi. To date, several bioactivities of halocynthiaxanthin have been reported, but its mechanism of digestion and absorption in mammals has not been studied yet. In this study, we evaluated the intestinal absorption of halocynthiaxanthin in mice. The halocynthiaxanthin-rich fraction was prepared from the tunicate Halocynthia roretzi. Mice were orally administered the fraction at a dose of 5 mg/kg body weight. The halocynthiaxanthin levels in the plasma, liver, and small intestine, were quantified using HPLC-PDA, 1, 3, 6, and 9 h after ingestion. The halocynthiaxanthin-rich fraction mainly consisted of the all-trans form and a small amount of cis forms. These three isomers were detected in the plasma of mice 3 h after ingestion. Time-course changes after the ingestion of this fraction were found, with cis isomers being more abundant than the all-trans isomer in the mouse plasma and liver. In the small intestine, however, the all-trans isomer was primarily detected. The possibility that cis isomers might be absorbed rapidly from the small intestine cannot be denied, but our results suggest that dietary all-trans-halocynthiaxanthin might be isomerized to the cis isomer after intestinal absorption.  相似文献   
29.
Polyclonal immunoglobulin (Ig) G autoantibodies against insulin have been identified in sera of healthy cats. We purified and fractionated insulin-binding IgGs from cat sera by affinity chromatography and analyzed affinity of insulin-binding IgGs for insulin and their epitopes. Following the passing of fraction A, which did not bind to insulin, insulin-binding IgGs were eluted into two fractions, B and C, by affinity chromatography using a column fixed with bovine insulin. Dissociation constant (KD) values between insulin-binding IgGs and insulin, determined by surface plasmon resonance analysis (Biacore™system), were 1.64e−4 M for fraction B (low affinity IgGs) and 2e−5 M for fraction C (high affinity IgGs). Epitope analysis was conducted using 16 peptide fragments synthesized in concord with the amino acid sequence of feline insulin by an enzyme-linked immunosorbent assay. Fractions B and C showed higher absorbance (affinity) of the peptide fragment of 10 amino acid residues at the carboxyl-terminal of the B chain (peptide No. 19), followed by peptide fragments of 6 to 15 amino acid residues of the B chain (peptide No. 8). Fraction C showed a higher absorbance to 7 to 16 amino acid residues of the B chain (peptide No. 5) compared with the absorbance of fraction B. Polyclonal insulin-binding IgGs may form a macromolecule complex with insulin through the multiple affinity sites of IgG molecules. Feline insulin-binding IgGs are multifocal and may be composed of multiple IgG components and insulin.  相似文献   
30.
Angiogenesis plays an important role in the proliferation and metastasis mechanisms of malignant tumors. Vascular endothelial growth factor (VEGF), a group of cytokines that contribute to angiogenesis and vasculogenesis. This study aimed to investigate the serum VEGF-A concentrations in dogs with various proliferative diseases. A total of 202 dogs that were histopathologically diagnosed with proliferative diseases were included in the study. Serum VEGF-A concentrations were measured using enzyme-linked immunosorbent assay. Median serum VEGF-A concentrations in dogs were as follows: healthy dogs, 4 pg/ml [0–21 pg/ml]; hepatocellular carcinoma, 30 pg/ml [0–158 pg/ml, P=<0.001]; hepatocellular adenoma, 32 pg/ml [0–49 pg/ml, P=0.003]; hepatic nodular hyperplasia, 18 pg/ml [0–51 pg/ml, P=0.595]; adrenal pheochromocytoma, 32 pg/ml [0–187 pg/ml, P=<0.001]; adrenocortical carcinoma, 32 pg/ml [3–161 pg/ml, P=0.002]; adrenocortical adenoma, 27 pg/ml [0–106 pg/ml, P=0.005]; colorectal adenocarcinoma, 36 pg/ml [0–75 pg/ml, P=0.002]; colorectal adenoma, 43 pg/ml [0–48 pg/ml, P=0.144]; inflammatory colorectal polyps, 37 pg/ml [0–111 pg/ml, P=<0.001]; pulmonary adenocarcinoma, 35 pg/ml [4–107 pg/ml, P=0.002]; pulmonary histiocytic sarcoma, 35 pg/ml [0–131 pg/ml, P=0.016]; and follicular thyroid carcinoma, 35 pg/ml [0–106 pg/ml, P=0.009]. The serum VEGF-A concentrations were significantly higher in dogs with neoplastic lesions compared to healthy dogs, except for colorectal adenoma. High serum VEGF-A concentrations were observed in dogs with proliferative diseases. The present study suggests that angiogenesis-inhibiting therapy, which targets VEGF-A, may be useful for canine neoplastic diseases.  相似文献   
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