Activity of roemerine against MRSA XJ75302 in a mouse sepsis model.

<p>Survival of BALB/c mice inoculated by i.p. injection with MRSA XJ75302 and treated with 20 mg/kg roemerine, oxacillin, vancomycin or sterile water by i.p. administration. Values with statistical significance by the log-rank test are indicated by an asterisks: *<i>P</i><0.05, ***<i>P</i><0.001 versus Model group.</p

Effects of roemerine on the growth of bacteria colonies.

<p>Roemerine, vancomycin and oxacillin were added to cell cultures containing <i>S</i>. <i>aureus</i> ATCC29213, MRSA XJ75302, Mu50, or LAC, respectively, with addition of an equal volume of sterile water as a control. Aliquots of each culture were collected at 0, 3, 6, 12, and 24 h, and were then diluted and inoculated on solid agar. The number of colony-forming units (CFUs) was calculated from the number of colonies growing on plates, and the data are the means for three replicates. CON, control; ROE, roemerine; VAN, vancomycin; OXA, oxacillin. *<i>P</i><0.05, **<i>P</i><0.01, ***<i>P</i><0.001 versus Control.</p

Roemerine-mediated bacterial membrane permeabilization (original magnification, ×1000).

<p>(A) Cultured <i>S</i>. <i>aureus</i> ATCC29213 was treated with 0, 32, 64 or 128 μg/mL of roemerine for 6 h, then were stained with the dyes SYTO 9 (which stains live bacteria) and propidium iodide (which stains dead bacteria). The stained bacteria were analyzed by fluorescence microscopy to assess viability. (B) The numbers indicate the percentages of live bacteria within <i>S</i>. <i>aureus</i> ATCC29213 after treatment with different concentrations of Roemerine. (C) The numbers indicate the percentages of dead bacteria within <i>S</i>. <i>aureus</i> ATCC29213 after treatment with different concentrations of Roemerine.</p

Concentration-dependent inhibition of roemerine on the growth of four <i>S</i>. <i>aureus</i>.

<p>Roemerine was added to cell cultures containing different tested strains to a final concentration 8, 16, 32, or 64 μg/mL, with addition of an equal volume of sterile water as a control. The growth curves for four tested strains were measured using a BioscreenC™ instrument in the absence and presence of different concentrations of roemerine. The sample frequency was one hour and data at time points are the means for three replicates. ROE, roemerine. *<i>P</i><0.05, **<i>P</i><0.01, ***<i>P</i><0.001 versus Control.</p