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Lysozyme Concentrations (lysozyme + concentration)
Selected AbstractsNon-specific immune response of turbot, Scophthalmus maximus (L.), experimentally infected with a pathogenic Vibrio pelagiusJOURNAL OF FISH DISEASES, Issue 6 2003L Villamil Abstract The effect of a pathogenic Vibrio pelagius, isolated during a mass mortality of turbot larvae, on the non-specific immune response of turbot, Scophthalmus maximus (L.), macrophages was studied both in vitro and in vivo. The in vitro treatment of head kidney (HK) macrophages with viable V. pelagius caused a significant inhibition of the chemiluminescence (CL) response in comparison with untreated macrophages, while incubation with heat-killed bacteria did not affect this response. In vivo, the intraperitoneal injection of V. pelagius resulted in a significant inhibition of the CL response in infected fish at days 1 and 4 post-infection compared with the control fish response. The HK macrophage nitric oxide (NO) production was enhanced by in vitro incubation with intermediate doses of viable V. pelagius (5 × 103 and 5 × 104 bacteria mL,1) and higher doses of the heat-killed bacteria (5 × 104,5 × 106 bacteria mL,1). In both cases, the NO inhibitorN- , -nitro-L-arginine was capable of down-regulating the specific NO induction caused by incubation with the bacterial treatments. In contrast, incubation with ECPs at higher doses caused a reduction in NO production. In vivo, a significant enhancement in NO production was also observed in macrophage supernatants at day 10 post-infection. Lysozyme concentration in the serum was also significantly increased in the experimentally infected fish at days 4 and 10 post-injection. In addition, viable V. pelagius and its ECPs significantly reduced HK macrophage viability in vitro, whereas no significant differences in viability were observed during the incubation with heat-killed bacteria. As NO production was enhanced in the experimentally infected fish, the inhibitory effect of the NO donor, S-nitroso-acetyl-penicillamine (SNAP), was tested in vitro in a cell-free assay. The results showed that growth of V. pelagius was significantly inhibited using SNAP at a high concentration (1 mm). [source] Functional Properties of Antimicrobial Lysozyme-Chitosan Composite FilmsJOURNAL OF FOOD SCIENCE, Issue 8 2004S.-I. Park ABSTRACT: Lysozyme-chitosan composite films were developed for enhancing the antimicrobial properties of chitosan films. A 10% lysozyme solution was incorporated into 2% chitosan film-forming solution (FFS) at a ratio of 0%, 20%, 60%, and 100% (w lysozyme/w chitosan). Films were prepared by solvent evaporation. Lysozyme release from the film matrix, the antimicrobial activity of films against Escherichia coli and Streptococcus faecalis, and basic film properties were investigated. The lysozyme release proportionally increased with increasing initial concentration of lysozyme in the film matrix, and the amount of released lysozyme was in natural log relationship with time. The films with 60% lysozyme incorporation enhanced the inhibition efficacy of chitosan films against both S. faecalis and E. coli, where 3.8 log cycles reduction in S. faecalis and 2.7 log cycles reduction in E. coli were achieved. Water vapor permeability of the chitosan films was not affected by lysozyme incorporation, whereas the tensile strength and percent elongation values decreased with increased lysozyme concentration. Scanning electron microscopy images revealed that lysozyme was homogeneously distributed throughout the film matrix. This study demonstrated that enhanced antimicrobial activity of lysozyme-chitosan composite films can be achieved by incorporating lysozyme into chitosan, thus broadening their applications in ensuring food quality and safety. [source] [Ru(bpy)2(dcbpy)NHS] Labeling/Aptamer-Based Biosensor for the Detection of Lysozyme by Increasing Sensitivity with Gold Nanoparticle AmplificationCHEMISTRY - AN ASIAN JOURNAL, Issue 11 2008Jianguo Bai Abstract A novel [Ru(bpy)2(dcbpy)NHS] labeling/aptamer-based biosensor combined with gold nanoparticle amplification for the determination of lysozyme with an electrochemiluminescence (ECL) method is presented. In this work, an aptamer, an ECL probe, gold nanoparticle amplification, and competition assay are the main protocols employed in ECL detection. With all the protocols used, an original biosensor coupled with an aptamer and [Ru(bpy)2(dcbpy)NHS] has been prepared. Its high selectivity and sensitivity are the main advantages over other traditional [Ru(bpy)3]2+ biosensors. The electrochemical impedance spectroscopy (EIS) and atomic force microscopy (AFM) characterization illustrate that this biosensor is fabricated successfully. Finally, the biosensor was applied to a displacement assay in different concentrations of lysozyme solution, and an ultrasensitive ECL signal was obtained. The ECL intensity decreased proportionally to the lysozyme concentration over the range 1.0×10,13,1.0×10,8,mol,L,1 with a detection limit of 1.0×10,13,mol,L,1. This strategy for the aptasensor opens a rapid, selective, and sensitive route for the detection of lysozyme and potentially other proteins. [source] Characterization of Fish-Skin Gelatin Gels and Films Containing the Antimicrobial Enzyme LysozymeJOURNAL OF FOOD SCIENCE, Issue 5 2006C.K. Bower ABSTRACT:, Fish skins are rich in collagen and can be used to produce food-grade gelatin. Films cast from fish-skin gelatins are stable at room temperature and can act as a barrier when applied to foods. Lysozyme is a food-safe, antimicrobial enzyme that can also produce gels and films. When cold-water, fish-skin gelatin is enhanced with lysozyme, the resulting film has antimicrobial properties. The objective of this study was to characterize the effect on strength and barrier properties of lysozyme-enhanced fish-skin gelatin gels and films, and evaluate their activity against potential spoilage bacteria. Solutions containing 6.67% fish-skin gelatin were formulated to contain varying levels of hen-egg-white lysozyme. Gels were evaluated for strength, clarity, and viscoelastic properties. Films were evaluated for water activity, water vapor permeability, and antimicrobial barrier capabilities. Fish-skin gels containing 0.1% and 0.01% lysozyme had pH (4.8) and gelling-temperatures (2.1 °C) similar to lysozyme-free fish-skin gelatin controls. However, gel strength decreased (up to 20%). Turbidities of gels, with or without lysozyme, were comparable at all concentrations. Films cast with gelatin containing lysozyme demonstrated similar water vapor permeabilities and water activities. Lysozyme was still detectable in most fish gelatin films. More antimicrobial activity was retained in films cast with higher lysozyme concentrations and in films where lysozyme was added after the gelatin had been initially heated. These results suggest that fish-skin gelatin gels and films, when formulated with lysozyme, may provide a unique, functional barrier to increase the shelf life of food products. [source] The Effect of Acute Ethanol Intoxication on Salivary Proteins of Innate and Adaptive ImmunityALCOHOLISM, Issue 4 2008Napoleon Waszkiewicz Background:, Human salivary proteins: peroxidase, lysozyme, lactoferrin, and IgA, participate in the protection of oral tissues, as well as upper digestive and respiratory tracts, against a number of microbial pathogens. In the current study, we investigated the effect of acute consumption of a large dose of ethanol on representative human salivary proteins of the innate and adaptive immune systems. Methods:, Eight healthy male volunteers drank an average of 2.0 g (1.4 to 2.5 g/kg) body weight of ethanol, in the form of vodka, in the 6-hour period. Samples of resting whole saliva were collected 12 hours before, then 36 and 108 hours after, the alcohol consumption. The levels of total protein, immunoglobulin A, lysozyme and lactoferrin as well as peroxidase activity were determined in saliva. Results:, At 36 hours after alcohol consumption, salivary protein and lysozyme concentrations as well as peroxidase activity were significantly decreased (p = 0.002, p = 0.043, and p = 0.003, respectively), in comparison to the values obtained at 12 hours before drinking. Between 36 and 108 hours after alcohol consumption, the salivary protein and lysozyme concentrations, as well as peroxidase activity showed a tendency to increase, although at 108 hours after the drinking session, the concentration of protein and peroxidase activity were still significantly lower than before drinking. There was no significant change in the level of lactoferrin, after the drinking session. The salivary concentration of IgA tended to increase at 36 hours after alcohol consumption, and at 108 hours it was significantly higher (p = 0.028), when compared to IgA concentration in the saliva collected before drinking (from 8% to 26% and 32% of total protein content, respectively). Conclusion:, Our report is the first to show that acute ingestion of relatively large, yet tolerable dose of alcohol, significantly disturbs salivary antimicrobial defense system. Reduced lysozyme level and decreased peroxidase activity may contribute to increased susceptibility to infections, when acute alcohol intake coincides with exposure to pathogens. [source] Concentration Of Egg White Lysozyme In The Serum Of Healthy Subjects After Oral AdministrationCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 1-2 2002Seiichi Hashida SUMMARY 1. While the egg white lysozyme preparation ER0068 (NeuzymŽ; Eisai, Tokyo, Japan) is widely used clinically, no studies have been performed on its pharmacokinetic properties at clinically relevant doses. In the present study, we used a highly sensitive two-site enzyme immunoassay in order to determine the pharmacokinetic properties of egg white lysozyme after oral administration of two doses within the clinical range, paying particular attention to the effects of food intake. 2. A total of 22 healthy male subjects aged 20,45 years participated in the study. All subjects had been screened for egg white allergy and non-specific lysozyme inhibitors in their serum. Subjects who received 90 mg ER0068 after an overnight fast reached a maximum serum concentration of 1700 pg/mL within 1 h, compared with non-detectable levels in untreated controls. In a second experiment, subjects received 30 and 90 mg ER0068 after an overnight fast and 90 mg in the non-fasted state and exhibited maximum serum levels of 37, 360 and 49 pg/mL, respectively. Egg white lysozyme concentrations in serum returned to undetectable levels after a maximum of 48 h. 3. We conclude that clinically relevant concentrations of egg white lysozyme are absorbed in significant amounts, despite its high molecular weight. However, food intake considerably reduces the amount of enzyme absorbed. [source] | |||||||||||||