Advanced Materials Research Vols. 887-888

Abstract: The antibacterial activity of extracts from Gentiana farreri Balf. f. was studied using Bnfillus licheniformis, Aeruginosus Bacillus, Staphylococcus aureus, Streptococcus pneumoniae and Escherichia coli as the test bacteria by Oxford cup. Meanwhile, the MIC of each extraction part of the ethanol extracts were determined. The results showed that the EtOAc extracts displayed the best antibacterial activity, the n-BuOH extracts had the lower activity, and the petroleum ether extracts had the lowest activity. The antibacterial activity enhanced along with the increase of sample concentration.

Abstract: This experiment applies orthogonal test to determine the proportion of concentrates of herbal medicine, and the final product meets the standard of GB5009, 392003. The test of microorganism and expired date represents that the oyster sauce can restrain bacteria and prolong its shelf lives. The final product can also clear heat and improve the immunity.

Abstract: Glutaraldehyde cross-linked chitosan coated-alginate microspheres were prepared to improve site specificity in colonic drug delivery system. Microspheres were characterized by microscopic image analysis, DSC and IR to study the formation of microspheres structure as well as the chemical interactions between drug and polymer. Microscope observation showed good spherical and homogeneous of microspheres. The glutaraldehyde cross-linked microspheres could produce Schiff base reaction and decrease chitosan hydrogen bonding interaction with mucous membrane. The drug loading of chitosan coated-alginate microspheres reached 43% and in vitro release properties of microspheres without cecal contents reached 20.96% after 12 h. The release profiles indicated that microsphere has a satisfactory sustained release behavior. Glutaraldehyde cross-linked chitosan coated-alginate microspheres have a great potential use in drug delivery system.

Abstract: A kind of drug releasing 3D porous material was designed and fabricated, which could used for bone repairing. The β-tricalcium phosphate (β-TCP) material were fabricated through the rapid prototyping (RP) combining with the freeze-drying, where the scaffold-mould was fabricated by RP. The material was fabricated with ball-milled slurry which solid content was 40%, the pre-freezing temperature was-10°C, and then the material was freeze-dried under vacuum environment at-30°C without sintering. The test results showed that the material had good structure pores with the mean size of 150μm through controlling the pre-freezing temperature, and the compressive strength of the samples was 0.216Mpa.

Abstract: Do the research of acidic zinc chloride treatment system to achieve poplar APMP with chemical swelling. The research showed that acidic zinc chloride can effectively swelling poplar APMP pulp, increase the fiber volume and loose the structure, acting concentrated in the amorphous region of the fiber which can help the penetration of chemicals and products of the dissolution. Because the differences of processing system pH and ionic effect, acidic zinc chloride combined alkaline hydrogen peroxide treatment can produce swelling synergistic effect.

Abstract: The aim of this study was to investigate the surface composition and morphology of fast-growing Alkaline peroxide mechanical pulping (APMP). Surface ultrastructure of APMP were modified by cellulase. The fiber ultrastructure and cellulose crystallinity before and after treatment with cellulose enzyme were analyzed by Atomic force microscopy (AFM). The results showed that surface particle size can be reduced to 300nm and bump of fiber surface became obvious. According to the phase contrast image and topography, cell wall region separate clearly. The specific surface area of single fiber became bigger.

Abstract: The isometric tension was measured in rat aortic rings. The extract from Clerodendranthus spicatus (CS) can enhance the relaxation induced by ACh in lower concentration and has a notable difference on SNP-induced relaxation in male and female. The relaxation of CS is also related to the inhibition of intracellular Ca²⁺ increase.

Abstract: Glutaraldehyde (GA) cross-linked silk fibroin (SF) films were prepared and the structural change were investigated by Fourier transform infrared spectroscopy and differential scanning calorimetry. The results were utilized to reveal the influence of GA cross-linking on the release properties of SF materials. It was found that GA induced conformational transition of SF from random coil to beta-sheet and had influence on the interaction between the peptide chains of SF, resulting in great changes in mechanical and dissolution properties, as well as drug release feature of the films. With increasing GA content, tensile strength of films first increases and then decreases, reaching a maximum around 7.5 %. The cross-linking was found to increase the flexibility and stability of SF films in water, and reduce the burst release of Rhodamine B, a model compound for small drug. The release of Rhodamine B exhibited a continuous and steady release after the initial burst, of which the release rate had a good linear fit to beta-sheet content in the matrix, suggesting that the silk II crystal could be used as a natural regulator for drug release from SF material.

Abstract: AMPK is ubiquitous in eukaryotes.It takes part in cells metabolism and is called energy receptor.It is activated with AMP/ATP ratio increasing.At present,metformin is used to activate AMPK in order to regulate glucose metabolism and treat diabetes.In this article,we summarize the structure activity of AMPK and its effects on glucose and lipid metabolism.

Abstract: Abietic acid was isolated by means of isomerization and amination reaction-crystallization coupled with ultrasonic wave. Isomerization rosin and ethanolamine were used as raw materials, 95% ethanol as recrystallization solvent, the effects of reaction temperature, reaction time, agitating velocity, ultrasound intensity and recrystallization times on the purity and yield of abietic acid were investigated. The suitable isolation conditions were obtained as follow: reaction temperature 30 °C, reaction time 40 min, agitating velocity 400 rpm, ultrasound intensity 300 W and freeze crystallization of amine salt three times. The purity and yield of abietic acid were 98.52% and 54.93% when the suitable conditions were used. And it was then characterization by its melting point, specific rotation, UV, FTIR and NMR, all evidence indicated that the purification product was abietic acid.