Advanced Materials Research Vol. 815

Abstract: LMW Branched Polyethylenimine-graft-lentinan was synthesized by performing crosslinker CDI in the presence of water-soluble Polysaccharide (Mw 70,000) and polyethylenimine (PEI, Mw 600). The chemistry of the PEI-g-lentinan obtained were characterized. The results indicated that the amines of lentinan were grafted with PEI. Gel electrophoresis showed that DNA migration was retarded completely at a N/P ratio of 10/1, indicating good DNA condensation capability of PEI-g-lentinan. The cytotoxicity of PEI-g-lentinan was evaluated, and the results reflected that PEI-g-lentinan had a lower cytotoxicity than PEI (25 K). Gene transfection efficiency of PEI-g-chitosan in cos-7 cells was determined. Remarkably,PEI-g-lentinan showed a higher transfection efficiency than that of PEI (25 K) in vitro.

Abstract: Defatted crayfish shell waste (CSW) was prepared by the removal of extractable fat with cyclohexane. CSW was pretreated by benzoic acid and demineralized by acids. Proteins in the pretreated CSW were extracted with NaOH and 0-4% NaCl concentrations with 0.05% CaCl₂ at pH 5.5-6.6 for 1 h at 50°C. By using the salt extraction procedure, CSW protein concentrate (29 g) was obtained from pretreated CSW (100 g). Recovery of protein was dependent on the extraction temperature employed; recovery values ranged from 33.2 to 51.4%. At 4% NaCl concentration, CaCl₂ increased protein solubility by 30%, compared to the control. The adhesiveness of saltextractable protein at various pH values ranging from 5.0 to 9.0 was investigated. At pH 6.0-8.0, adhesiveness of salt-extractable protein showed the highest value (78.2 kg). The adhesiveness increased linearly as the salt-extractable protein concentration increased up to 24% with respect to temperature for salt-extractable protein adhesiveness, the greatest adhesiveness was in the range of 70 to 90. Improved adhesiveness and water resistance were observed with 0.05% glutaraldehyde treatment.

Abstract: Oligonucleotides are essential components of many applications in molecular biology. The synthesis chemistry is robust and commercial oligonucleotide synthesizers have taken advantage of the chemistry to provide oligonucleotides of high quality and purity. This paper established nucleic acid synthesis platform to carry out the synthesis of the labeled nucleic acid probes based on the DNA synthesizer and solid-phase synthesis technology. We chose to study the automated synthesis starting from DMT protected FAM labeled amidite attached to controlled pore glass (CPG) support and the standard trityl-off oligonucleotide synthesis cycle was performed, yielding the solid-supported oligonucleotide. The reported automated solid-phase oligonucleotide synthesis procedure successfully employs the common iterative synthesis, deblocking, activation, coupling, capping, oxidation, and isolation steps in standard oligonucleotide synthesis. The automated synthetic approach can also be applied to oligonucleotides of different length, composition of nucleotide, demonstrating the universality of the method. Moreover, the synthesis involved the use of commercially available, safe, stable, and inexpensive reagents, particularly advantageous and attractive for their use in automated solid-phase synthesis. The synthesis allows custom tailoring of their structure to the requirements of biological assays within hours, as opposed to traditional approaches that require weeks or months of work in the laboratory. Therefore it will become much easier to investigate biological interactions and optimize for objectives such as the receptor mediated targeting of oligonucleotides.

Abstract: Fungus corrodes silk and makes their products quickly corrosion and crisp. This article disclosed that the silk fabrics treated with finishing resins containing isothiazolone to form the closing film. On the one hand, the film can prevent fungus penetrating into silk fiber matrix. On the other hand, it can make use of the antimicrobial of isothiazolone to improve its function. So the protection method can change the single isolation action to produce double action way and prevent fungus penetrating into silk fiber matrix.

Abstract: [ObjectivTo study the extraction technology of flavonoids from orange peel in order to provide some theoretical guidance for the industrial production of flavonoids from orange peel. [Metho Taking orange peel as raw material, which was citrus fruit processing waste and the flavonoid yield as index, with ultrasonic assisted extraction, through single factor experiments and orthogonal tests to optimization of the extraction technology, obtain optimum process conditions of orange flavonoid by ultrasonic assisted extraction. [Result As for ultrasonic assisted extraction, the yield of orange flavonoid reached 9.6% under extraction conditions of extracting time 30 min, alcohol concentration 60%, sedimentation ratio 1:25.

Abstract: PVA hydrogel has been used in the field of cartilage replacement in recent year. In order to improve the water-keeping ability of PVA gel and mechanical property, PVP was introduced into PVA and crosslinked by adding ammonium persulfate to form a composite gel. The crosslinkage of the gel was identified, and the effect of PVP and ammonium persulfate amount on the composite gel was studied. The crosslinkage, the degree of swelling and the compress stress of the composite gels have been tested. UV analysis was used to investigate the release of PVP from the composite gels. The dried composite gels were put into water to investigate the degree and velocity of the rehydration of different composite gels.

Abstract: Calcium sulfate/tri-calcium phosphate (CaSO₄/TCP) composite bone fillers were fabricated through molding method. Their structure and properties were characterized by infrared spectroscope, scanning electronic spectroscope, x-ray diffraction and degradation test. The results show that TCP crystals were attached to the CaSO₄ crystals and prevented the growing of sulfate crystals. So their size is shorter than that of CaSO₄ crystals prepared from pure CaSO₄ semihydrate, and some even had defect. The resorption rate of CaSO₄ bone fillers was decreased when TCP was incorporated.

Abstract: To find the inner relations of extrusion key parameters, 2-factor and 3-level orthogonal experiments are carried out on the twin-screw extruder with the corn-rice powder as the materials. The factors are: screw rate and feed rate; the indices are: inner pressure, die outlet temperature and generator current. The results are analyzed by single index regression method, the results show that the screw rate has the significant influence on the variables of barrel inner pressure, die outlet temperature and generator current, while the feed rate only impact significantly on the barrel inner pressure and generator current. After the response analysis of the original variables, the desired experimental conditions are obtained. The parameters should be: screw rate=150rpm, feed rate=14rpm.

Abstract: This study used Ag-embedded nanoTiO₂, xylan and water-soluble Chitosan as antibacterial agents, respectively prepared shutter blades through the treating solution of the different concentration and the different drug loading amount of the poplar veneer. Through a single factor experiment, this paper analyzes that the different antibacterial agent, concentration of antibacterial agent and the drug loading amount have an effect on the antibacterial properties of the shutter blades. The results show that the order of antibacterial performance of the shutter blades impregnated antibacterial agents is the Ag-embedded nanoTiO₂, Chitosan, Xylan. Comprehensiv-ely thought the antibacterial properties and economic index, the optimal concentration of the Ag-embedded nanoTiO₂ impregnation solution is 1%.

Abstract: t was reported that more than 1 billion tons of straw is produced in China each year. Because of difficulties in degradation, farmers usually burn the straw by themselves. In this paper, corn stover was chosen to represent straw and microorganisms were used to produce organic fertilizer in order to render the straw harmless. Also organic fertilizer can improve soil quality and reduce the dosage of chemical fertilizers. 5 Microorganisms which were Bacillus subtilis, Bacillus licheniformis, Bacillus thermophiles, Pseudomonas stutzeri and Zymomonasmobilis were selected by high CMC enzymatic activity.Then, a multi-bacterium was designed which could improve fermentation efficiency. To save energy, water resources and improve fermentation efficiency, the fermentation device in the lab was improved.