Abstract:

BACKGROUND: There are high rates of bacterial infection on the surface of implanted biomaterials in diabetic patients; it is uncertainly high of infection rate in non-diabetic patients with hyperglycemia during the operation. Few studies report the effect of different concentrations of glucose on the bacterial biofilms formed on the surface of biomaterial in vitro.
OBJECTIVE: To investigate the effect of high concentration of glucose on the biofilms on the surface of biomaterial in Staphylococcus epidermidis.
METHODS: Staphylococcus epidermidis model of biomaterial infection was cultured in different concentrations of glucose. Biofilms mass was semi-quantified by crystal violet dye. The thicknesses of biofilms were measured by confocal laser scanning microscope.
RESULTS AND CONCLUSION: Semi-quantitative experiments showed that the absorbance values of biofilm formation positive strains (Staphylococcus epidermidis ATCC35984) was greater than 0.12, with the increasing concentration of glucose in the culture medium, the absorbance values also raised and reached a peak at 50 mmoL/L glucose concentration. Confocal laser microscopy demonstrated that, on biofilm formation positive strains (Staphylococcus epidermidis ATCC35984), the biofilm was significantly thicker in ≥ 11.1 mmoL/L glucose group compared with no glucose group (P < 0.05). The maximum value of biofilm formation occurred with 50 mmoL/L glucose. There were no biofilms formed in biofilm negative strains (Staphylococcus epidermidis ATCC12228). High concentration of glucose can induce the formation of biofilms in Staphylococcus epidermidis, controlling glucose is more important to decrease the incidence rate of biomaterial infection in diabetes mellitus.