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121.
Pradeep Paudel Su Hui Seong Se Eun Park Jong Hoon Ryu Hyun Ah Jung Jae Sue Choi 《Marine drugs》2021,19(6)
Phlorotannins are polyphenolic compounds in marine alga, especially the brown algae. Among numerous phlorotannins, dieckol and phlorofucofuroeckol-A (PFF-A) are the major ones and despite a wider biological activity profile, knowledge of the G protein-coupled receptor (GPCR) targets of these phlorotannins is lacking. This study explores prime GPCR targets of the two phlorotannins. In silico proteocheminformatics modeling predicted twenty major protein targets and in vitro functional assays showed a good agonist effect at the α2C adrenergic receptor (α2CAR) and an antagonist effect at the adenosine 2A receptor (A2AR), δ-opioid receptor (δ-OPR), glucagon-like peptide-1 receptor (GLP-1R), and 5-hydroxytryptamine 1A receptor (5-TH1AR) of both phlorotannins. Besides, dieckol showed an antagonist effect at the vasopressin 1A receptor (V1AR) and PFF-A showed a promising agonist effect at the cannabinoid 1 receptor and an antagonist effect at V1AR. In silico molecular docking simulation enabled us to investigate and identify distinct binding features of these phlorotannins to the target proteins. The docking results suggested that dieckol and PFF-A bind to the crystal structures of the proteins with good affinity involving key interacting amino acid residues comparable to reference ligands. Overall, the present study suggests α2CAR, A2AR, δ-OPR, GLP-1R, 5-TH1AR, CB1R, and V1AR as prime receptor targets of dieckol and PFF-A. 相似文献
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The ethyl acetate soluble fraction of Broussonetia kazinoki at 50 microg/ml showed a significant inhibition (78.2%) of nitric oxide (NO) in lipopolysaccharide activated macrophages. Kazinol B, an isoprenylated flavan, was identified as the active principle. It inhibits the NO synthesis with an IC(50) of 21.6 microM. 相似文献
124.
Suruga K Nagasawa N Yamada S Satoh T Kawachi R Nishio T Kume T Oku T 《Journal of agricultural and food chemistry》2003,51(23):6835-6843
Commercial cytochrome c (Cyt c) was irradiated with Co-60 gamma-rays in the dose range of up to 3.0 kGy to investigate the enhancement of the nitrite reducing activity of Cyt c. The optimum irradiation dose to induce nitrite reducing activity for 30 muM Cyt c solution was 1.0 kGy under an O(2) atmosphere. The nitrite reducing activity of Cyt c irradiated at this dose was approximately 45-fold that of unirradiated Cyt c and ca. 1.2-fold that of nitrite reductase. The irradiation treatment resulted in unfolding of the peptide chain, exposure of the heme group, oxidation of methionine to methionine sulfoxide, dissociation of the sixth ligand (Met), and occurrence of autoxidation in Cyt c. Sepharose-immobilized irradiated Cyt c had a similar activity to that in solution. The resin retained the activity after five uses even after 1 year of storage. The irradiated Cyt c will be able to be used as a substitute for nitrite reductase. 相似文献
125.
Four concentrations of Zn bacitracin (0, 50, 100 and 150 mg/kg) added to diets of two different planes of nutrition were fed to male broiler chicks for 7 weeks. Feeding broilers Zn bacitracin significantly improved growth rate and food conversion, and increased shank pigmentation. The effects of Zn bacitracin were independent of the plane of nutrition. Regression analyses revealed that the responses of birds were linear. 相似文献
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128.
Alam MS Kajiki R Hanatani H Kong X Ozoe F Matsui Y Matsumura F Ozoe Y 《Journal of agricultural and food chemistry》2006,54(4):1361-1372
To study the interaction of phenylheterocycles with gamma-aminobutyric acid (GABA) receptors, 4- or 5-alkyl(or phenyl)-1-phenyl-1H-1,2,3-triazoles were synthesized and examined for their ability to inhibit the specific binding of [3H]-4'-ethynyl-4-n-propylbicycloorthobenzoate (EBOB), a noncompetitive antagonist, to the housefly and rat GABA receptors, as well as to the beta3 subunit homo-oligomer of the human GABA receptor investigated as a model receptor. 4-Substituted 1-phenyl-1H-1,2,3-triazoles were found to be more potent competitive inhibitors than the 5-substituted regioisomers in the case of all receptors. The 4-tert-butyl or 4-n-propyl analogue of 1-(2,6-dichloro-4-trifluoromethylphenyl)-1H-1,2,3-triazole exhibited the highest level of inhibition of [3H]EBOB binding to all receptors. Most of the synthesized analogues were more active in terms of the inhibition of EBOB binding to the housefly and human beta3 GABA receptors than to the rat receptor. The 4-cyclohexyl analogue showed the highest (185-fold) housefly versus rat receptor selectivity. A three-dimensional quantitative structure-activity relationship (3D-QSAR) analysis demonstrated that both the 4-trifluoromethyl-2,6-dichloro substitution on the phenyl ring and a small, bulky, hydrophobic substituent at the 4-position of the triazole ring played significant roles in conferring high potency in cases involving the housefly and human beta3 receptors. The human beta3 receptor resembled the housefly receptor in terms of their recognition of phenyltriazoles, whereas 3D-QSAR analysis revealed a slight difference between the two receptors in terms of their mechanisms of recognition of the para-substituent on the phenyl moiety. Some of the triazoles synthesized here exhibited insecticidal activity, which was correlated with their ability to inhibit [3H]EBOB binding to the housefly receptor. Thus, 1-phenyl-1H-1,2,3-triazoles with the appropriate substituents exert insecticidal activity by selectively acting at the site for noncompetitive antagonism of insect GABA receptors. 相似文献
129.
Yeon-Joo Kim Won-Ki Yoon Si-Yun Ryu Ki-Jung Chun Hwa-Young Son Sung-Whan Cho 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(1):19-23
This study was performed to investigate the biological effects of boron neutron capture therapy (BNCT) on the testes and eyes in mice using HANARO Nuclear Reactor, Korea Atomic Energy Research Institute. BNCT relies on the high capacity of 10B in capturing thermal neutrons. Sodium borocaptate (BSH, 75 ppm, iv) and boronophenylalanine (BPA, 750 ppm, ip) have been used as the boron delivery agents. Mice were irradiated with neutron (flux: 1.036739E +09, Fluence 9.600200E+12) by lying flat pose for 30 (10 Gy) or 100 min (33 Gy) with or without boron carrier treatment. In 45 days of irradiation, histopathological changes of the testes and eyes were examined. Thirty-three Gy neutron irradiation for 100 min induced testicular atrophy in which some of seminiferous tubules showed complete depletion of spermatogenic germ cells. Lens epithelial cells and lens fiber were swollen and showed granular changes in an exposure time dependent manner. However, boron carrier treatment had no significant effect on the lesions. These results suggest that the examination of histopathological changes of lens and testis can be used as "biological dosimeters" for gauging radiation responses and the HANARO Nuclear Reactor has sufficient capacities for the BNCT. 相似文献
130.
Estimation of rice protein content before harvest using ground-based hyperspectral imaging and region of interest analysis 总被引:1,自引:0,他引:1
Hiroyuki Onoyama Chanseok Ryu Masahiko Suguri Michihisa Iida 《Precision Agriculture》2018,19(4):721-734
Protein content, which represents rice taste quality, must be estimated in order to create a harvesting plan as well as next year’s basal dressing fertilizer application plan. Ground-based hyperspectral imaging with high resolution (1 × 1 mm per pixel) was used for estimating the protein content of brown rice before harvest. This paper compares the estimation accuracy of rice protein content estimation models generated from the mean reflectances of five regions of interest (ROIs): the overall target area, dark area (less illuminated parts of the rice plants), canopy area (leaves, yellow leaves, and ears), leaf area, and ear and yellow leaf area. The size of the target sampling area was 0.85 × 0.85 m. An R + G + B histogram and a GNDVI–NDVI image were used to separate the target area into the individual ROIs. The values of the coefficient of determination R 2 and the root mean square error of prediction (RMSE) were similar for each model: R 2 ranged from 0.83 to 0.86 and RMSE ranged from 0.27 to 0.30% for all models except for the dark area model, where R 2 = 0.76 and RMSE = 0.35%. There were no significant differences in the magnitude of the estimation error among all models. This result indicates that it is not necessary to obtain an image with a ground resolution that is greater than 0.85 × 0.85 m per pixel to estimate rice protein content before harvest. This result should provide useful information when deciding the altitude of platforms for imaging rice fields. 相似文献