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Peptidoglycan recognition proteins (PGRPs) belong to a member of pattern-recognition receptors (PRRs), which proposed as antibacterial protein. The present study investigated the antibacterial effect of BpPGRP5 in great blue-spotted mudskipper (Boleophthalmus pectinirostris). BpPGRP5 transcript was detected in all tested tissues with the highest expression level in spleen, and its expression was significantly upregulated in spleen, intestine, and kidney following Aeromonas veronii infection. rBpPGRP5 was found to interact with several polysaccharides and bacteria, including Gram-negative bacteria (Escherichia coli and A. veronii) and Gram-positive bacteria (Listeria monocytogenes and Staphylococcus aureus). rBpPGRP5 inhibited the proliferation of E. coli, S. aureus, L. monocytogenes, and A. veronii in a Zn

Osteoprotegerin (OPG) is a member of the tumor necrosis factor receptor superfamily, contributing to inflammation, apoptosis, and differentiation. However, the function of OPG in the host immune system of teleosts remains unclear. Here, we cloned the cDNA of the LcOPG gene from large yellow croaker. LcOPG mRNA was expressed in all analyzed tissues and was upregulated by Vibrio alginolyticus infection in immune tissues and monocytes/macrophages (MO/MФ). Subsequently, the LcOPG protein was expressed and purified using a prokaryotic expression system. Recombinant LcOPG protein (rLcOPG) treatment suppressed V. alginolyticus-induced pro-inflammatory cytokine and enhanced V. alginolyticus-induced anti-inflammatory cytokine mRNA expression. Furthermore, rLcOPG decreased V. alginolyticus-induced MO/MФ apoptosis. Therefore, the results indicate that LcOPG might play a role in the immune response of V. alginolyticus-infected large yellow croaker.

Adsorption behavior of phenanthrene on cetyltrimethyl ammonium bromide (CTAB)-modified polystyrene (PS) microspheres was investigated thoroughly to develop a novel adsorbent material. CTAB-modified PS microspheres were characterized through atomic force microscopy (AFM) and Brunauer–Emmet–Teller analysis. AFM images showed that conical admicelles made of CTAB replaced polyvinylpyrrolidone (PVP) macromolecules on the surface of the PS microspheres. After CTAB modification, the surface area of the PS microspheres increased noticeably from 0.56 to 2.08 m2 g−1, which confirmed that the formation of discrete CTAB admicelles replaced PVP macromolecules coated on the surface of the PS microspheres. Through conductivity measurements, two critical micelle concentrations (CMCs) were obtained. The first was the CMC of CTAB admicelles on the PS microspheres, and the second was the CMC of CTAB micelles in the solution, which further confirmed the formation of the admicelles on PS microspheres. Cation–π electron interaction between CTAB and phenanthrene helped adsolubilize phenanthrene in the admicelles on the CTAB-modified PS microspheres. The equilibrium adsorption capacity of the CTAB-modified PS microspheres for phenanthrene was 11.67 mg g−1, nearly three times that of the untreated PS microspheres. The adsorption kinetic curves of phenanthrene on CTAB-modified PS microspheres followed a pseudo-second-order model. The adsorption process closely fit the Freundlich model, which indicated a multilayer adsorption process, rather than monolayer behavior.

Salinity stress have detrimental effect on teleosts and may increase susceptibility to disease. Betaine is a compound utilized by organisms to regulate osmotic pressure and plays an important role in the immune response and anti-inflammatory functions. Here, the protective effects of betaine against Vibrio anguillarum infection of ayu under conditions of salinity was determined. A total of 60 ayu were cultured at 10 ppt salinity for 14 days, all fish were intraperitoneally injected with 100 μL of 100 or 200 mg/kg of betaine or saline on days 0, 2, 4, and 6. The fish were subsequently infected with V. anguillarum. The results showed that betaine treatment improved the survival rate of V. anguillarum-infected ayu. Betaine treatment decreased the bacterial load and histological damage in the head-kidney, liver, and spleen. Besides, the inflammatory response was decreased by betaine in V. anguillarum-infected ayu tissues and monocytes/macrophages (MO/MФ). Furthermore, in hypertonic-exposed MO/MФ (19 mOsm), betaine treatment enhanced phagocytosis activity and promoted the bacterial killing capability. Finally, we found that betaine mediated the inflammatory response through BGT-1 in V. anguillarum-infected ayu MO/MФ. In conclusion, when exposed to osmotic stress, betaine was able to mediate the host defense in ayu and modulate the antibacterial response through MO/MФ.

Basic magnesium chloride whisker is described as a cheap and available whisker material. The preparation and application prospect of basic magnesium chloride whisker were introduced in this paper, and the use of abundant concentrated seawater or brine resources in the preparation of basic magnesium chloride whisker was prospected.

It is a kind of high efficiency and energy saving new method to prepare high purity magnesium oxide (MgO) with magnesium carbonate tri-hydrate (MgCO3·3H2O) as intermediate. Our research group had already designed orthogonal experimental and got the optimal process conditions of MgCO3·3H2O. The operating parameters such as temperature, pH and reaction time had been further optimized in this paper. Intermediate MgCO3·3H2O with high aspect ratio and good settling performance was synthesized at the optimal temperature 40-50°C,the optimal pH 8.8-9.0, the optimal reaction time70min, the optimal condition also applied to brine system.

The research status of high purity magnesium oxide preparation is introduced in this paper. First, process for preparing high purity MgO is summarized, the global and domestic production status of high purity magnesia is also described. Finally, the problems and disadvantages of current MgO preparation methods are concluded, also development direction of preparation method basing on brine utilization in the production of MgO is put forward.

Magnesium borate (Mg2B2O5) whisker was successfully synthesized by high temperature flux method using Magnesium chloride, boric acid, sodium hydroxide and sodium chloride as raw materials.The as-prepared product was characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy(SEM), Transmission Electron Microscope (TEM) and X-Ray Photoelectron Spectrometry (XPS). The results showed that the as-prepared sample had triclinic structure and consisted of whisker-like particles with an average diameter about 1.25 μm and length up to 40μm. XPS results confirmed that the molar ratio of each atom agreed with the stoichiometric composition of Mg2B2O5. The growth mechanism was briefly discussed.