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排序方式: 共有332条查询结果,搜索用时 46 毫秒
1.
Sargassum horneri (S. horneri), an edible brown alga, has been proposed as a functional food with an improvement effect on abnormal skin immune responses. The present study investigates the anti-allergic effect of an ethanol extract from S. horneri (SHE) on immunoglobulin E (IgE)/bovine serum albumin (BSA)-mediated activation in bone marrow-derived cultured-mast cells (BMCMCs) and passive cutaneous anaphylaxis (PCA) reaction in mice. SHE markedly and dose-dependently suppressed the degranulation of BMCMCs by reducing the β-hexosaminidase and histamine release without cytotoxicity. In addition, SHE significantly decreased the FcεRI expression on the surface of BMCMCs and its IgE binding. Moreover, SHE reduced the mRNA expression and the production of allergic cytokines; interleukin (IL)-1β, IL-4, IL-5, IL-6, IL-10, IL-13; interferon (IFN)-γ and/or tumor necrosis factor (TNF)-α; and a chemokine, thymus and activation-regulated chemokine (TARC), by suppressing the activation of Src-family kinases and nuclear factor (NF)-κB signaling. In further study, the application of SHE reduced the PCA reaction in an IgE/BSA-induced type I allergic mice model. Taken together, we suggest that SHE has an anti-allergic effect in type I allergic responses.  相似文献   
2.
This study was conducted to evaluate the effects of dietary supplementation of Barodon, an anionic alkali mineral complex, on growth, feed utilization, humoral innate immunity and disease resistance of olive flounder. A basal experimental diet was used as a control and supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5% Barodon. Triplicate groups of fish (26.4 ± 0.2 g) were fed one of the diets to apparent satiation twice daily for 10 wk. The growth performance was enhanced (P < 0.05) linearly and quadratically in fish fed diets containing Barodon compared with that in fish fed the control. Feed utilization was significantly improved by Barodon supplementation. Serum lysozyme and antiprotease activities were increased quadratically in Barodon fed groups. Also, significantly higher superoxide dismutase activity was found in Barodon‐fed fish. Dietary supplementation of 0.1–0.3% Barodon resulted in significant enhancement of fish disease resistance against Streptococcus iniae. The findings in this study indicate that dietary supplementation of Barodon can enhance growth, feed utilization, innate immunity, and disease resistance of olive flounder and that the optimum level seems to be 0.1% in diets.  相似文献   
3.
Antibacterial and antifungal activity of pinosylvin, a constituent of pine   总被引:1,自引:0,他引:1  
Lee SK  Lee HJ  Min HY  Park EJ  Lee KM  Ahn YH  Cho YJ  Pyee JH 《Fitoterapia》2005,76(2):258-260
The antibacterial and antifungal activities of pinosylvin (3,5-dihydroxy-trans-stilbene), a constituent of pine, were studied and compared with those of resveratrol (3,5,4'-trihydroxy-trans-stilbene). Pinosylvin exhibited more potent growth inhibitory activity against Candida albicans and Saccharomyces cerevisiae.  相似文献   
4.
After far-infrared (FIR) radiation onto rice hull, a methanolic extract was prepared for the determination of antioxidant ability. After 30 min of FIR treatment, the radical scavenging activity and total phenol contents of rice hull extracts increased from 47.74 to 79.63% and from 0.12 to 0.19 mM, respectively, compared to control. Inhibition of lipid peroxidation in extracts was also increased from 41.07 to 47.96%. According to the GC-MS analysis, more phenolic compounds (p-coumaric acid, 3-vinyl-1-oxybenzene, p-hydroxybenzaldehyde, vanillin, p-hydroxybenzoic acid, and 4,7-dihydroxyvanillic acid) were detected in FIR-irradiated rice hull extract. These results indicated that FIR radiation onto rice hull could liberate and activate covalently bound phenolic compounds that have antioxidant activities.  相似文献   
5.
It has been reported that soybean peptide fractions isolated from Korean fermented soybean paste exert angiotensin I converting enzyme (ACE) inhibitory activity in vitro. In this study, further purification and identification of the most active fraction inhibiting ACE activity were performed, and its antihypertensive activity in vivo was confirmed. Subsequently, a novel ACE inhibitory peptide was isolated by preparative HPLC. The amino acid sequence of the isolated peptide was identified as His-His-Leu (HHL) by Edman degradation. The IC(50) value of the HHL for ACE activity was 2.2 microg/mL in vitro. Moreover, the synthetic tripeptide HHL (spHHL) resulted in a significant decrease of ACE activity in the aorta and led to lowered systolic blood pressure (SBP) in spontaneously hypertensive (SH) rats compared to control. Triple injections of spHHL, 5 mg/kg of body weight/injection resulted in a significant decrease of SBP by 61 mmHg (p < 0.01) after the third injection. These results demonstrated that the ACE inhibitory peptide HHL derived from Korean fermented soybean paste exerted antihypertensive activity in vivo.  相似文献   
6.
A competitive indirect enzyme-linked immunosorbent assay (ciELISA) for the organophosphorus insecticide acephate, O,S-dimethyl acetylphosphoramidothioate, was developed using a polyclonal antibody. Five different haptens mimicking the analyte were synthesized and conjugated with the carrier proteins bovine serum albumin (BSA) and keyhole limpet hemocyanin (KLH) by the N-hydroxysuccinimide active ester and diazotization methods. Polyclonal antibodies raised against hapten-KLH conjugates in rabbits and hapten-BSA conjugates as coating antigens were screened and selected for the assay in the homologous and heterologous ELISA systems. The effects of various assay conditions such as detergent, organic solvents, pH, and preincubation of the mixture of the polyclonal antibody and the analyte on the sensitivity were evaluated. The IC(50) value for acephate was 25 ng/mL in an optimized heterologous system using hapten-4-BSA as a coating antigen and a polyclonal antibody no. 8377 against hapten-1-KLH, showing the detection range of 5-140 ng/mL and the lowest detection limit of 2 ng/mL. The cross-reactivities of the structurally related organophosphorus insecticides, including the major metabolite of the analyte, methamidophos, were less than 1%. Recoveries from the analyte-fortified tap water, mulberry leaves, and lettuce samples in the assay were in the range of 72-121% by simple extraction, concentration, and dilution. These results indicate that the ELISA could be a convenient and supplemental analytical tool for monitoring acephate residues in environmental and agricultural samples.  相似文献   
7.
The growth-inhibiting activity of anthraquinone-2-carboxylic acid and lapachol identified in the inner bark of taheebo, Tabebuia impetiginosa, toward 10 human intestinal bacteria was evaluated by using a paper disk diffusion bioassay and compared to those of seven lapachol congeners (1,4-naphthoquinone, naphthazarin, menadione, lawsone, plumbagin, juglone, and dichlone) as well as two commercially available antibiotics, chloramphenicol and tetracycline. Anthraquinone-2-carboxylic acid exhibited very strong growth inhibition of Clostridium paraputrificum at 1 microg/disk while 100 microg/disk of lapachol was needed for moderate growth inhibition of the same organism. These two isolates exhibited weak inhibition of Clostridium perfringens and Escherichia coli at 100 microg/disk while no adverse effects were observed on the growth of Bifidobacterium adolescentis, Bifidobacterium bifidum, Bifidobacterium infantis, Lactobacillus acidophilus, and Lactobacillus casei at 1000 microg/disk. Structure-activity relationships indicate that a methyl group in the C-2 position of 1,4-naphthoquinone derivatives might play an important role in antibacterial activity.  相似文献   
8.
The acaricidal activity of materials derived from rhizome of Atractylodes ovata (Atractylodes macrocephala) toward adult Dermatophagoides farinae and Dermatophagoides pteronyssinus was examined using fabric-circle residual contact and vapor-phase toxicity bioassays. Results were compared with those of the currently used acaricides: benzyl benzoate, dibutyl phthalate, and N,N-diethyl-m-toluamide (Deet). The active principles of A. ovata rhizome were identified as the sesquiterpenoids, atractylenolide III (1) and atractylon (2), by spectroscopic analysis. In fabric-circle residual contact bioassays with adult D. farinae, atractylenolide III (LD50, 103.3 mg/m2) and atractylon (136.2 mg/m2) were five and four times more toxic than Deet and 1.7- and 1.3-fold more active than dibutyl phthalate, respectively, based on 24 h LD50 values. These compounds were less toxic than benzyl benzoate (LD50, 45.8 mg/m2). Against adult D. pteronyssinus, atractylenolide III (LD50, 73.8 mg/m2) and atractylon (72.1 mg/m2) were eight times more active than Deet and 2.5-fold more toxic than dibutyl phthalate. These compounds were slightly less effective than benzyl benzoate (LD50, 46.0 mg/m2). In vapor-phase toxicity tests with both mite species, atractylenolide III and atractylon were effective in closed but not in open containers. These results indicate that the effect of these sesquiterpenoids was largely a result of action in the vapor phase. Naturally occurring atractylenolide III and atractylon merit further study as potential house dust mite control agents or leads because of their great activity as a fumigant.  相似文献   
9.
Pressure-assisted thermal processing (PATP) is being widely investigated for processing low acid foods. However, its microbial safety has not been well established and the mechanism of inactivation of pathogens and spores is not well understood. Fourier transform infrared (FT-IR) spectroscopy was used to study some of the biochemical changes in bacterial spores occurring during PATP and thermal processing (TP). Spore suspensions (approximately 10(9) CFU/mL of water) of Clostridium tyrobutyricum, Bacillus sphaericus, and three strains of Bacillus amyloliquefaciens were treated by PATP (121 degrees C and 700 MPa) for 0, 10, 20, and 30 s and TP (121 degrees C) for 0, 10, 20, and 30 s. Treated and untreated spore suspensions were analyzed using FT-IR in the mid-infrared region (4000-800 cm(-1)). Multivariate classification models based on soft independent modeling of class analogy (SIMCA) were developed using second derivative-transformed spectra. The spores could be differentiated up to the strain level due to differences in their biochemical composition, especially dipicolinic acid (DPA) and secondary structure of proteins. During PATP changes in alpha-helix and beta-sheets of secondary protein were evident in the spectral regions 1655 and 1626 cm(-1), respectively. Infrared absorption bands from DPA (1281, 1378, 1440, and 1568 cm(-1)) decreased significantly during the initial stages of PATP, indicating release of DPA. During TP changes were evident in the bands associated with secondary proteins. DPA bands showed little or no change during TP. A correlation was found between the spore's Ca-DPA content and its resistance to PATP. FT-IR spectroscopy could classify different strains of bacterial spores and determine some of the changes occurring during spore inactivation by PATP and TP. Furthermore, this technique shows great promise for rapid screening PATP-resistant bacterial spores.  相似文献   
10.
The toxic effects of Eucalyptus globulus leaf oil-derived monoterpenoids [1,8-cineole, l-phellandrene, (-)-alpha-pinene, 2-beta-pinene, trans-pinocarveol, gamma-terpinene, and 1-alpha-terpineol] and the known Eucalyptusleaf oil terpenoids (beta-eudesmol and geranyl acetate) on eggs and females of the human head louse, Pediculus humanus capitis, were examined using direct contact and fumigation bioassays and compared with the lethal activity of delta-phenothrin and pyrethrum, two commonly used pediculicides. In a filter paper contact bioassay with female P. h. capitis, the pediculicidal activity was more pronounced with Eucalyptus leaf oil than with either delta-phenothrin or pyrethrum on the basis of LT(50) values (0.125 vs 0.25 mg/cm(2)). 1,8-Cineole was 2.2- and 2.3-fold more toxic than either delta-phenothrin or pyrethrum, respectively. The pediculicidal activities of (-)-alpha-pinene, 2-beta-pinene, and (E)-pinocarveol were comparable to those of delta-phenothrin and pyrethrum. l-Phellandrene, gamma-terpinene, and 1-alpha-terpineol were relatively less active than delta-phenothrin and pyrethrum. beta-Eudesmol and geranyl acetate were ineffective. 1-alpha-Terpineol and (E)-pinocaveol were highly effective at 0.5 and 1.0 mg/cm(2), respectively, against P. h. capitis eggs. At 1.0 mg/cm(2), (-)-alpha-pinene, 2-beta-pinene, and gamma-terpinene exhibited moderate ovicidal activity, whereas little or no ovicidal activity was observed with the other terpenoids and with delta-phenothrin and pyrethrum. In fumigation tests with female P. h. capitis at 0.25 mg/cm(2), 1,8-cineole, (-)-alpha-pinene, (E)-pinocarveol, and 1-alpha-terpineol were more effective in closed cups than in open ones, indicating that the effect of the monoterpenoids was largely due to action in the vapor phase. Neither delta-phenothrin nor pyrethrum exhibited fumigant toxicity. Eucalyptus leaf oil, particularly 1,8-cineole, 1-alpha-terpineol, and (E)-pinocaveol, merits further study as potential pediculicides or lead compounds for the control of P. h. capitis.  相似文献   
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