Papers by Author: Xin He

Abstract: The purpose of this study was to explore the potential application of the combination of microemulsion as a topical delivery vehicle in enhancing the absorption and efficacy of tripterygium wilfordii multiglycoside (TWM). Various microemulsion formulations were developed and an optimal microemulsion (TWM-ME)，which presented spherical droplets and consisted of RH-40, IPM and water was 27: 3.3: 69.7 by weight. It possessd an average droplet size of 23.6 nm, a low viscosity of (3.56±0.12) mm2•s-1 Zeta electric potential was (–5.35±0.42) mV, refractive index was (1.3617±0.0051) nD20, conductivity was (97.6±3.6) μs/cm. Compared to the control solution, TWM-ME provided better skin permeability in vitro. Moreover, TWM-ME has noticeable anti-inflammatory and immune suppression effect. These results indicate that the combination of microemulsion represents an effective vehicle for topical delivery of TWM.

Abstract: Eight swainsonine (SW)-degrading bacteria were isolated from the soil where locoweed was buried for 6 months and one of the strains (YLZZ-2) was selected for further study. Based on morphology, physiologic tests, 16S rDNA sequence, and phylogenetic characteristics, the strain showed the greatest similarity to members of the order Stenotrophomonap and the closest to members of the Stenotrophomonas maltophilia group. The ability of the strain to degrade SW, as sole carbon source, was investigated under different culture conditions. The preferential temperature and initial pH value for the strain were 25～35 °C and 6.0～9.0, respectively. The optimal temperature for the strain was 30 °C and the optimal pH value was 7.0. There was positive correlation between degradation rate and inoculation amount. The growth of stain YLZZ-2 and degradation rate were fast, and YLZZ-2 could completely degradate 400 mg/L swainsoine within 24 h. There was a linear relationship between the growth of stain YLZZ-2 and degradation of swainsonine. These results highlight the potential of this bacterium to be used in detoxifying of SW in livestock consuming locoweed.

Abstract: An Ag-Ce-TiO2 composite film was prepared by incorporating Ag in the Ce-TiO2 films with an impregnation method through photoreduction. The bactericidal activity of the Ag-Ce-TiO2 composite film and the effect of deposition of silver and doping cerium in the different irradiations on the antibacterial performance were assessed against Escherichia coli (E. coli). TIhrough characterization of X-ray diffraction (XRD), X-ray photoelectronic spectra (XPS) and UV/VIS diffusive reflectance spectra (DRS), it was found that the Ag-Ce-TiO2 composite film was composed of predominant anatase titania, cerium oxides (in the form of Ce2O3/CeO2) and silver nanoparticles. Moreover, the bactericidal activity of the Ag-Ce-TiO2 composite film and the effect of deposition of silver and doping cerium in the different irradiations on the antibacterial performance were assessed against Escherichia coli (E. coli). The results show that the Ag-Ce-TiO2 composite film has much higher antibacterial efficiency than that of glass and pure TiO2 film either in the room light or in the dark. Therefore, this composite film is promising in applications of antimicrobial and self-clean technologies.