Objective Fungal keratitis（FK） is a vision-threatening infection,whose treatment requires more effective and safer anti-fungal agent exploitation urgently.With this aim,we focused on the effect of an extracellular p...Objective Fungal keratitis（FK） is a vision-threatening infection,whose treatment requires more effective and safer anti-fungal agent exploitation urgently.With this aim,we focused on the effect of an extracellular polysaccharide on fungal adhesion to human corneal epithelial cells.Methods We performed the cytotoxicity assays of the extracellular polysaccharide EPS-II from an antarctic bacterium Pseudoaltermonas and evaluated its inhibitory effect on Candida albicans cells＇ adherence to human corneal epithelial cells（HCECs）.Results EPS-II,which displayed minor cytotoxicity but also promoted proliferation of HCECs,could inhibit the adherence of yeast cells to HCECs in a dose-dependent manner.EPS-II could also suppress the subsequent PI3K/AKT signaling pathway,and thereby decrease the expression of early inflammatory cytokines.Conclusions ExtracellularpolysaccharideEPS-IIwassuggestedasanewnaturalagentforattenuatingFK.展开更多
The rough crystal of exopolysaccharide produced by Enterococcus durans, a strain of lactic acid bacteria screened from the intestine of a cock in our laboratory, was purified by CM-cellulose column chromatography, DEA...The rough crystal of exopolysaccharide produced by Enterococcus durans, a strain of lactic acid bacteria screened from the intestine of a cock in our laboratory, was purified by CM-cellulose column chromatography, DEAE-Sephadex A-25 ionexchange and Sephadex G-100 gel chromatography to give EPS-Ⅰ. The EPS-Ⅰ was eluted as a single peak in HPLC analysis, indicating the homogeneity of EPS-Ⅰ and free from low-molecular-weight polysaccharides. The molecular weight of the EPS-Ⅰ was determined as 42 000 by the light scattering method. The result of its elemental analysis was C 41.08% and H 7.23% without the elements of N, P and S. Monosaccharide analysis showed that it was composed of Glc and Man in a molar ratio of 4∶1. Sugar composition analysis, methylation analysis and 1H and 13C NMR spectroscopy revealed that the EPS-Ⅰ was composed of pentasaccharide repeating units. The sequence of sugar residues was determined by using two-dimensional NMR, including heteronuclear multiple-bond correlation(HMBC) and nuclear overhauser effect spectroscopy(NOESY). The structure of the pentasaccharide repeating unit of EPS-Ⅰ was given, a new excellular polysaccharide from lactic acid bacterium compared with other EPSs was reported.展开更多
[Objective] The aim was to investigate the effect of Echinacea purpurea polysaccharide （EPS） on IL-6 mRNA expression level in IEC-6 cell after lipopolysac- charide （LPS） injury. [Method] Total RNA of IEC-6 cell wa...[Objective] The aim was to investigate the effect of Echinacea purpurea polysaccharide （EPS） on IL-6 mRNA expression level in IEC-6 cell after lipopolysac- charide （LPS） injury. [Method] Total RNA of IEC-6 cell was extracted with TRIzon reagent and amplified by R-r-PCR. The amplification products were examined by a- garose gel electrophoresis and graphed for analysis. [Result] After stimulation by LPS, the IL-6 mRNA expression level in iEC-6 cell increased. However, EPS could inhibit this effect, and the inhibitory effect was dose-dependent. At the concentration of 50 μg/ml, EPS could partially inhibit the IL-6 mRNA expression in IEC-6 cell after LPS stimulation; in the concentration range of 100-500 μg/ml, the inhibitory effect of EPS on IL-6 mRNA expression in iEC-6 cell increased with the increase of con- centration. When the IEC-6 cell was pre-treated with EPS （50, 100, 200 and 500 μg/ml） for 24 h and then stimulated with LPS （10 μg/ml） for 1 and 4 h, respectively, it was found that the LPS-induced mRNA expression of IL-6 in IEC-6 cell was in- hibited by EPS, and this kind of inhibitory effect was time-dependent. [Conclusion] After small intestinal epithelial cells were stimulated by LPS, the IL-6 mRNA expres- sion level increased. However, EPS could inhibit the LPS-induced mRNA expression of IL-6, thus protecting the intestinal mucosa. In addition, this kind of inhibitory effect showed time and concentration dependence.展开更多
The influencing factors of extracellular polysac-charide(EPS)produced from a strain of lactic acid bacteria(LAB L15)were studied by using the phenol-H2SO4 method.It was demonstrated that the strain produced EPS at the...The influencing factors of extracellular polysac-charide(EPS)produced from a strain of lactic acid bacteria(LAB L15)were studied by using the phenol-H2SO4 method.It was demonstrated that the strain produced EPS at the most amount when it was incubated for 40-48 h and when the pH value was 4 under 30℃.Glucose was the most suitable carbon source for LAB-producing EPS.The rough EPS was obtained from L15 culture after centrifugation,dialysis,deprotein,decoloration,and ethanol-precipitation.The sample was at least composed of two polysaccharides that were completely different in molecular weight and the amount.The purified EPS was passed through the SephadexG-200 column and it showed that it was a sample purified by thin layer chromatography.展开更多
基金partially supported by the National Natural Scientific Foundation (81000369)the Doctor Foundation of Shandong Province (BS2009SW018)
文摘Objective Fungal keratitis（FK） is a vision-threatening infection,whose treatment requires more effective and safer anti-fungal agent exploitation urgently.With this aim,we focused on the effect of an extracellular polysaccharide on fungal adhesion to human corneal epithelial cells.Methods We performed the cytotoxicity assays of the extracellular polysaccharide EPS-II from an antarctic bacterium Pseudoaltermonas and evaluated its inhibitory effect on Candida albicans cells＇ adherence to human corneal epithelial cells（HCECs）.Results EPS-II,which displayed minor cytotoxicity but also promoted proliferation of HCECs,could inhibit the adherence of yeast cells to HCECs in a dose-dependent manner.EPS-II could also suppress the subsequent PI3K/AKT signaling pathway,and thereby decrease the expression of early inflammatory cytokines.Conclusions ExtracellularpolysaccharideEPS-IIwassuggestedasanewnaturalagentforattenuatingFK.
文摘The rough crystal of exopolysaccharide produced by Enterococcus durans, a strain of lactic acid bacteria screened from the intestine of a cock in our laboratory, was purified by CM-cellulose column chromatography, DEAE-Sephadex A-25 ionexchange and Sephadex G-100 gel chromatography to give EPS-Ⅰ. The EPS-Ⅰ was eluted as a single peak in HPLC analysis, indicating the homogeneity of EPS-Ⅰ and free from low-molecular-weight polysaccharides. The molecular weight of the EPS-Ⅰ was determined as 42 000 by the light scattering method. The result of its elemental analysis was C 41.08% and H 7.23% without the elements of N, P and S. Monosaccharide analysis showed that it was composed of Glc and Man in a molar ratio of 4∶1. Sugar composition analysis, methylation analysis and 1H and 13C NMR spectroscopy revealed that the EPS-Ⅰ was composed of pentasaccharide repeating units. The sequence of sugar residues was determined by using two-dimensional NMR, including heteronuclear multiple-bond correlation(HMBC) and nuclear overhauser effect spectroscopy(NOESY). The structure of the pentasaccharide repeating unit of EPS-Ⅰ was given, a new excellular polysaccharide from lactic acid bacterium compared with other EPSs was reported.
基金Supported by National Natural Science Foundation of China(31472230)Natural Science Foundation of Hebei Province(C2014407068)Project of Science and Technology Department of Hebei Province(14966610D)
文摘[Objective] The aim was to investigate the effect of Echinacea purpurea polysaccharide （EPS） on IL-6 mRNA expression level in IEC-6 cell after lipopolysac- charide （LPS） injury. [Method] Total RNA of IEC-6 cell was extracted with TRIzon reagent and amplified by R-r-PCR. The amplification products were examined by a- garose gel electrophoresis and graphed for analysis. [Result] After stimulation by LPS, the IL-6 mRNA expression level in iEC-6 cell increased. However, EPS could inhibit this effect, and the inhibitory effect was dose-dependent. At the concentration of 50 μg/ml, EPS could partially inhibit the IL-6 mRNA expression in IEC-6 cell after LPS stimulation; in the concentration range of 100-500 μg/ml, the inhibitory effect of EPS on IL-6 mRNA expression in iEC-6 cell increased with the increase of con- centration. When the IEC-6 cell was pre-treated with EPS （50, 100, 200 and 500 μg/ml） for 24 h and then stimulated with LPS （10 μg/ml） for 1 and 4 h, respectively, it was found that the LPS-induced mRNA expression of IL-6 in IEC-6 cell was in- hibited by EPS, and this kind of inhibitory effect was time-dependent. [Conclusion] After small intestinal epithelial cells were stimulated by LPS, the IL-6 mRNA expres- sion level increased. However, EPS could inhibit the LPS-induced mRNA expression of IL-6, thus protecting the intestinal mucosa. In addition, this kind of inhibitory effect showed time and concentration dependence.
文摘The influencing factors of extracellular polysac-charide(EPS)produced from a strain of lactic acid bacteria(LAB L15)were studied by using the phenol-H2SO4 method.It was demonstrated that the strain produced EPS at the most amount when it was incubated for 40-48 h and when the pH value was 4 under 30℃.Glucose was the most suitable carbon source for LAB-producing EPS.The rough EPS was obtained from L15 culture after centrifugation,dialysis,deprotein,decoloration,and ethanol-precipitation.The sample was at least composed of two polysaccharides that were completely different in molecular weight and the amount.The purified EPS was passed through the SephadexG-200 column and it showed that it was a sample purified by thin layer chromatography.
