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ABSTRACT: Jellyfish venom contains various toxins and can cause itching, edema, muscle aches, shortness of breath, blood pressure depression, shock or even death after being stung. Hemolytic protein is one of the most hazardous components in the venom. The present study investigated the hemolytic activity of the nematocyst venom from jellyfish Stomolophus meleagris. Anion exchange chromatography, DEAE Sepharose Fast Flow, and gel filtration chromatography, Superdex200 had been employed to isolate hemolytic proteins from the nematocyst venom of jellyfish Stomolophus meleagris. Hemolysis of chicken red blood cells was used to quantify hemolytic potency of crude nematocyst venom and chromatography fractions during the purification process. Native-PAGE profile displayed one protein band in the purified hemolytic protein (SmTX); however, two protein bands with apparent molecular weights of ∼45kDa and 52kDa were observed in the reducing SDS-PAGE analysis. Approximately 70μg/mL of SmTX caused 50% hemolysis (HU50) of the erythrocyte suspension. The hemolytic activity of SmTX was shown to be temperature and pH dependent, with the optimum temperature and pH being 37°C and pH 5.0. The present study is the first report of isolation and partial characterization of hemolytic proteins from the nematocyst venom of the jellyfish Stomolophus meleagris. The mechanism of the hemolytic activity of SmTX is not clear and deserves further investigation.
Toxicology in Vitro 04/2013; · 2.78 Impact Factor
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ABSTRACT: The effects of degradation on molecular weights (Mws) of polysaccharides from Enteromorpha prolifera were investigated. Microwave-assistance could highly accelerate reaction rate. Six representative sulfated polysaccharides (Mw 446.5, 247.0, 76.1, 19.0, 5.0 and 3.1KDa) were prepared by a microwave-assistance acid hydrolysis method. Chemical analysis and FT-IR spectrum showed only glycosidic linkages were cleft without breaking significant structural units. Antioxidant activities of representative polysaccharides revealed that all samples showed great inhibitory effects on superoxide radical at a low concentration compared to Vitamin C and samples with high Mws exhibited higher inhibitory effects. On the contrary, samples with low Mws possessed stronger inhibitory effects on hydroxyl radical, IC(50) of Mw 3.1KDa was 0.39mg/mL. The chelating effect of Mw 3.1KDa was 77.3% at 5mg/mL, which was twice more than initial polysaccharide. The study indicated Mw was the most significant factor to influence antioxidant activities of polysaccharides from E. prolifera.
Carbohydrate polymers. 02/2013; 92(2):1991-6.
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ABSTRACT: Highly purified chitooligomers with single degree of polymerization are of significance for studying bioactivity of chitooligomers. However, there are few reports on high-resolution preparative separation of chitooligomers, especially for those oligomers with degree of polymerization higher than 4. This study developed a high-resolution chromatography for the preparative separation of a pure fully deacetylated chitooligomer series. A glucosamine oligomer mixture with low degree of polymerization was prepared by acid hydrolysis of a highly deacetylated chitosan. Then, six fractions were separated from the prepared oligomer mixture by ion-exchange chromatography and analyzed by HPLC and ESI/MS, which primarily contained glucosamine dimers, trimers, tetramers, pentamers, hexamers, and heptamers, respectively, with chromatographic purities over 98% for dimers to hexamers and a purity of 93% for heptamers. The yields of a single round of separation were 75, 60, 60, 55, 35, and 20 mg for glucosamine dimers, trimers, tetramers, pentamers, hexamers, and heptamers, respectively. Furthermore, a chromatographic separation model for GlcN homomers was established. The capacity factor (k) of glucosamine oligomers and their degrees of polymerization (DPs) exhibited a good correlation, lnk = 0.786 + 0.846 lnDP, (R2 = 0.997). Based on this equation, glucosamine octamers are expected to be separated by this system.
Journal of Separation Science 01/2013; · 2.73 Impact Factor
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ABSTRACT: Reactive oxygen species (ROS) can damage the lipids, proteins and DNA when produced excessively in cells. Here, we describe the isolation and identification of a novel antioxidant protein named SmP90 from the nematocyst of jellyfish Stomolophus meleagris by 50% ammonium sulfate precipitation and gel filtration chromatography, superdex75. HPLC and SDS-PAGE analysis revealed >95% purity of SmP90 with apparent molecular weight of 90 kDa, approximately. The identification of SmP90 was confirmed by both N-terminal amino acids sequencing, with the sequences of NLDTPYCFYSGDYGG, and peptide mass fingerprint (PMF) analysis by MALDI-TOF-MS. However, no known protein had been completely matched in the database, which indicated that SmP90 might be a novel protein. The antioxidant assay result showed that it had strong superoxide anion radical-scavenging activity with the half-scavenging concentration (EC(50)) of about 16 μg/mL. Therefore, the present study is the first time to demonstrate a high efficient method of isolating a novel antioxidant protein from the nematocyst of jellyfish S. meleagris.
International journal of biological macromolecules 05/2012; 51(3):274-8. · 2.37 Impact Factor
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ABSTRACT: The nematocyst proteins of jellyfish Stomolophus meleagris, a complicated mixture, contain many important bioactive molecules. In present study, to gain comprehensive insight into the protein component and search some novel bioactive molecules in the nematocyst proteins, shotgun proteomic analysis of the nematocyst proteins was carried out by nano liquid chromatography tandem mass spectrometry (nanoLC-MS/MS) for the first time. Digested peptides of the nematocyst proteins were analyzed by nanoLC-MS/MS and all MS/MS spectra were then automatically searched by the SEQUEST program. A total of 181 proteins had been identified, with the molecular weight ranging from 5268.06 to 843,487.57 and the pI from 4.49 to 11.39. Bioinformatic analysis was also applied to better understand the identified proteins. In the gene ontology (GO) annotation, all the identified proteins were classified into 13, 9 and 7 groups according to biological process, cellular component and molecular function, respectively. Pathways analysis of the identified proteins was conducted with 33 corresponding pathways found. On the basis of pathways analysis, we also constructed the gene network to analyze the relationship of those genes each other, which contained enzyme-enzyme relation, protein-protein interaction and gene expression interaction.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 05/2012; 899:86-95. · 2.78 Impact Factor
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ABSTRACT: Hemolysin is one of the most hazardous components in the venom of Cyanea nozakii Kishinouye. Here we describe the purification and in vitro characterization of the hemolysin, which we named CnPH. The CnPH was isolated by anion-exchange and size-exclusion chromatography from the nematocyst venom. Two protein bands with molecular masses of 20 kDa, 60 kDa respectively were shown in the reducing SDS-PAGE analysis of the CnPH. And Approximately 5 μg/mL of the CnPH resulted in 50% hemolysis of the erythrocyte suspension. The hemolytic activity of the CnPH was both temperature and pH dependent. Moreover, it was significantly inhibited in the presence of divalent metal cations, including Cu(2+), Mg(2+), Mn(2+), Zn(2+) and Ca(2+), but enhanced in the presence of EDTA. However, how CnPH performs its hemolytic activity is not yet clear, therefore the mechanism of the hemolytic activity of the CnPH is under research.
International journal of biological macromolecules 03/2011; 49(1):14-9. · 2.37 Impact Factor
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ABSTRACT: This work describes the preparation of a chelating resin from chemically modified chitosan. The resin was synthesized by using O-carboxymethylated chitosan to cross-link a polymeric Schiff's base of thiourea/glutaraldehyde and characterized by IR. Batch method was applied for testing the resin's adsorption behavior. Adsorption experiments showed the resin had good adsorption capacity and high selectivity for Ag(I) in aqueous solution. The maximum uptake of Ag(I) exhibited was 3.77 mmol/g, at pH 4.0. The results also indicated that the adsorption process was exothermic and fit well with the pseudo-second-order kinetic model. Ag(I) desorption could reach 99.23% using 0.5 M thiourea-2.0 M HCl solution.
Journal of hazardous materials 08/2010; 180(1-3):577-82. · 4.14 Impact Factor
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ABSTRACT: In this work, a thiourea-modified chitosan derivative (TMCD) was synthesized through two steps, O-carboxymethylated first and then modified by a polymeric Schiff's base of thiourea/glutaraldehyde. The adsorption behavior of mercury (II) ions onto TMCD was investigated through batch method. The maximum adsorption capacity for Hg(II) was found to be 6.29 mmol/g at pH 5.0 and both kinetic and thermodynamic parameters of the adsorption process were obtained. The results indicated that adsorption process was spontaneous exothermic reaction and kinetically followed pseudo-second-order model. The adsorption experiments also demonstrated TMCD had high adsorption selectivity towards Hg(II) ions when coexisted with Cu(II), Zn(II), Cd(II) and Ca(II) in solution and it could be easily regenerated and efficiently reused.
International journal of biological macromolecules 03/2010; 46(5):524-8. · 2.37 Impact Factor
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ABSTRACT: Kanglemycin C (K-C) is a new immunosuppressant isolated from the culture broth of Nocardia mediterranei var. kanglensis 1747-64. To improve the productivity of K-C and to study the biological effects of space flight on its producing strain, spores from five K-C producing strains (U-10, U-15, U-7, M-13, gamma-33) mutated from the wild strain N. mediterranei var. kanglensis 1747-64 were carried into space by an unmanned spaceship, "Shenzhou III" (Divine Vessel III) on March 25, 2002. Comparatively, the strain U-7 was the highest K-C producing strain among the above five starting strains when cultivated in 500-ml Erlenmeyer flasks. After a 6 day and 18 h flight, the treated spores went through serial screening processes to screen for high-yield K-C mutant strains, using thin layer chromatography and high performance liquid chromatography (HPLC). The K-C yield produced by one mutant strain, designated as F-16, derived from the starting strain U-7 was increased by up to 200% when compared to that produced by the starting strain U-7 in 500-ml Erlenmeyer flasks after careful postflight HPLC analysis. Another mutant strain, designated as F-210, derived from the starting strain M-13 showed reduced productivity of K-C as well as exhibited changes in some morphological and physiological characteristics. For example, the broth color of the strain F-210 changed from yellow to purple after 96 h of culture, but that of the ground control strain M-13 remained yellow. Similarly, the mycelium morphological change from filamentous to coccoid of F-210 occurred later than that of ground control M-13. Examination of the survivability of postflight spores indicated that exposure to radiation, during the 162 h of space flight, plays a critical role in the survival rates of spores such that spores exposed to strong radiation exhibited lower survival rates than spores exposed to weak radiation.
Journal of Industrial Microbiology and Biotechnology 09/2006; 33(8):707-12. · 2.73 Impact Factor
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ABSTRACT: In order to find an effective absorbent material based on chitosan which has good adsorption selectivity for heavy metals, we prepared thiourea-modified chitosan resin with Pb(II) as template (TMCR template). TMCR template was synthesized by using O-carboxymethylated chitosan to absorb Pb(II) ions first and then being cross-linked with a polymeric Schiff's base of thiourea/glutaraldehyde. The effects of parameters such as pH, contact time, initial concentration and temperature on the adsorption of TMCR template were studied. The result showed the maximum uptake of Pb(II) was found to be 2.02 mmol/g at pH 6.0, 25 °C. Adsorption experiments showed the TMCR template had high selectivity for Pb(II) in solution containing binary mixtures with Cu(II), Zn(II), Cd(II) and Ni(II). The experimental data also indicated that the adsorption process was exothermic spontaneous and fit well with Lagergren's pseudo-second-order model in comparison to pseudo-first-order kinetic.
Carbohydrate Polymers.
