Advanced Materials Research Vols. 343-344

Abstract: Based on the soil test of heavy metals in wastewater irrigation area in eastern Inner Mongolia, this paper analyses the content of heavy metals Cr, Cu, Cd, Pb in different layers of soil samples and reveals the internal relations between heavy metal concentration gradient in the vertical direction and soil properties, thus providing a scientific basis to guide sewage irrigation, solve the problem of water shortage in wastewater irrigation area and carry out environmental impact assessment. Soil is an important subsystem in natural environmental systems, through which many pollutants, especially heavy metals, produced by human activities, enter the food chain and ultimately do harm to human health. Currently, heavy metal ion contamination to the soil caused by wastewater irrigation has become one of the focuses in the study of soil chemistry and agricultural environment pollution. For this reason, it is particularly important to study the migration mechanism of heavy metals in soil and to provide a reliable theoretical basis for the prevention and management of soil contaminants.

Abstract: Role of nitric oxide(NO) and hydrogen peroxide(H₂O₂) in eATP-inhibited reduction of in vitro pollen germination and tube growth of Paulownia tomentosa Steud. were studied. Results showed that exposure of the pollen to a series of eATP (0.2, 0.4, 0.6, 0.8, 1.0 mM) concentration for 3h resulted in not only the reduction of pollen germination but also the reduction of tube growth. Also, NOS inhibitor NG-nitro-L-Arg-methyl eater (L-NAME ), NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3- oxide(c-PTIO) and two scavengers of H₂O₂, ascorbic acid (ASC) and catalase (CAT) not only largely prevented eATP-inhibited pollen germination but also tube growth. These results indicated that NO and H₂O₂ are involved in eATP inhibited pollen germination and tube growth.

Abstract: The effect of long-term elevated CO₂ (as open top chambers) on rhizosphere and bulk bacterial community structure in Pinus sylvestriformis seedlings field was investigated in July, August, and September. The bacterial communities were processed by Denaturing Gradient Gel Electrophoresis (DGGE) analysis of bacterial 16S rDNA fragments amplified by PCR (Polymerase Chain Reaction) from DNA extracted directly from soil. DGGE profiles from rhizosphere samples showed large changes in rhizosphere bacterial community under elevated CO₂ compared to ambient except for that in September. For bulk samples, bacterial community structure changed when exposed to elevated CO₂ in three months. With the exception of bulk samples in August, a similitude of bacterial communities structures existed between different elevated CO₂ concentrations by analyzing UPGMA dendrogram based on Jaccard’s coefficient.

Abstract: A simple and rapid real-time quantitative PCR assay was devised to discriminate bacteriolytic from bacteriostatic activity for a given antibacterial agent. Bacteria suspension was incubated with the compound solution, the mixture was centrifuged and supernatant was removed completely, the obtained pellet was then used as the DNA template for PCR. Then the bacteriostatic and bacteriolytic activity can be inferred by the quantity of PCR product. Moreover, the parameters that influence the assay sensitivity was discussed.

Abstract: CO₂ emissions have serious impact on the world economy, especially at high-concentration. Green algae are known to have a tolerance to high CO₂ level. In this paper, the rate of CO₂ fixation using Chlorella Pyrenoidosa was analyzed in different environments. 1) Chlorella Pyrenoidosa fixed CO₂ slowly in air, while this alga could rapidly grow in high-concentration CO₂ until CO₂ level was beyond 10%. At 25% CO₂, the rate of CO₂ fixation was lower than that at 10% CO₂, but still 1.18 times as higher as in air. 2) At lower initial inoculation density of Chlorella Pyrenoidosa, its growth rate was relatively high but the rate of CO₂ fixation was low. When initial inoculation density beyond 0.187×108cells/ml, the average rate of CO₂ fixation was ranged from 2.786 gCO₂/L·d to 2.847 gCO₂/L·d. 3) During the five days, the average rate of CO₂ fixation was 3.044 gCO₂/L·d in NaNO₃ resource. When NH₄Cl or NaNO₂ is regarded as N resource, the rate of CO₂ fixation was almost neglectable.

Abstract: Chinese hickory (Carya cathayensis Sarg.) kernel protein isolate (CKPI) was isolated from hinese hickory kernel defatted flour (CKDF) by isoelectric precipitation. CKPI was evaluated for chemical composition and selected functional properties. CKPI contained over 72.0% dry weight (DW) of protein. Nitrogen solubility curves for CKPI were pH-dependent in the pH range of 2.0-12.0 with minimum solubility observed at pH 4.0 (9.8%) and maximum solubility at pH 12.0 (89.9%). Minimum emulsifying capacity (EC) and emulsifying stability (ES) of CKPI were observed at pH 4.0. CKPI had a least gelation concentration of (LGC) of 6% (w/v) at pH 4.0. Results indicated that Chinese hickory kernel may be a new protein source with huge exploitation potential after oil extraction process in China.

Abstract: The performance of thiacalix[4]arenetetrasulfonate (TCAS) for the treatment of soils contaminated with lead was evaluated in this study. Batch experiments were performed to test the factors influencing remediation of lead-polluted soil. The effects of temperature, solid-liquid ratio and the ionic strength on the removal capacities of lead by TCAS reagent had been studied. The results showed that the TCAS reagent was effective for removal of lead from the contaminated soil, the optimum temperature of TCAS for soil treatment was 5°C-25°C. The optimum solid-liquid ratio was 1:10 for soil treatment. Adding Ca(NO₃)2 was of no advantage for lead removal, and the effect of Ca(NO₃)2 on the removl rate was less when its molarity was less than 0.01mol/L. This experimental work has also demonstrated the great importance of soil matrix for the evaluation of the TCAS leaching as a cost effective remedial option.

Abstract: Purposes: To construct a recombinant vaccine alpha-fetoprotein (AFP)-heat shock protein (HSP70) complex, and study its ability to induce specific CTL response and its protective effect against AFP-producing tumor. Material/Methods: A recombinant vaccine was constructed by conjugating mouse alpha-fetoprotein to heat shock protein 70. By way of intracutaneous injection, mice were primed and boosted with recombinant vaccine mAFP/HSP70, whereas single mAFP or HSP70 injection as controls. The ELISPOT and ELISA were used to measure the frequency of cells producing the cytokine IFN-gama in splenocytes and the level of anti-AFP antibody of serum from immunized mice respectively. In vivo tumor challenges were carried out to assess the immune effect of the recombinant vaccine. Results: By recombinant mAFP/HSP70 vaccine immunization, the results of ELISPOT and ELISA showed that the number of splenic cells producing IFN-gama and the level of anti-AFP antibody of serum were significantly higher in mAFP/HSP70 group than those in mAFP and HSP70 groups (108.50±11.70 IFN-gama spots/106 cells vs 41.60±10.40 IFN-gama spots/106 cells, 7.32±3.14 IFN-gama spots/106 cells, P<0.01; 156.32±10.42 µg/mL vs 66.52±7.35 µg/mL, 5.73±2.89 µg/mL, P<0.01). The tumor volume in mAFP/HSP70 group was significantly smaller than that in mAFP and HSP70 groups (42.44±7.14 mm3 vs 392.23±12.46 mm3, 838.63±13.84 mm3, P<0.01). Conclusions: The study further confirmed the function of heat shock protein 70’s immune adjuvant. Sequential immunization with recombinant mAFP/HSP70 vaccine could generate effective antitumor immunity on AFP-producing tumor. The recombined mAFP/HSP70 vaccine may be suitable for serving as an immunotherapy for hepatocellular carcinoma.

Abstract: Fungal endophytes do not harm the plant when they live inside the host. Previous studies also showed that the content of some secondary metabolites are correlated to the endophytes within plant. Whether such a mutualistic symbiosis system could be implanted to bio-engineering or not will be an important and exciting problem. Here a fungal endophyte was co-cultured with the cell suspension of Acer ginnnala which is rich in gallich acid to test the problem above. The results showed that the growth of plant cells and the cell vitality decreased after the endophyte added, while gallic acid content increased. It was preliminarily determined that there is a partial competition relationship.

Abstract: Staphylococcus aureus is a pathogen responsible for purulent infection in humans and animals. To prevent disease of the nasopharynx, it is significant to prepare specific egg-yolk antibodies for determination establishment. In this paper, egg yolk antibody against staphylococcus aureus was prepared by immunization of laying hens with straphylococcus aureus as antigen. Egg yolk immunoglobulin (IgY) was isolated and purified from the egg yolks by polyethylene glycol 6000 and ammonia sulfate solution method. The titer and purify of IgY was evaluated by enzyme-linked immunosorbent assay (ELISA) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) respectively. Bacteriostatic effect was assayed with bacteriostatic test by plate method. Cross-reactivities with other bacterias were investigated by indirect ELISA. The specificity of IgY and antigen combination was assayed with agar-gel immunodiffusion method. The purity of IgY is 95.2 % and the titer is 1:5120. The IgY is with high specificity of streptococcus aureus. It can bind to staphylococcus aureus antigen well. The results indicate it provide a new approach to determine and prevent staphylococcus aureus.