Effect of Commercially Available Synthetic Insulin on the Biofilm Formation in S. aureus and E. coli Bacterial Strains

摘要

Biofilms are microorganisms that play a huge role in various fields of study. Bacterial ability for biofilm formation can be examined in the presence of different host substances which may affect the biofilm formation capability in different ways. Synthetically used hormones are substances used by patients in order to supply their hormonal deficit. One of the most widely used synthetically-produced hormones is insulin. The hormone is used for treatment of diabetes patients. In our study we examined the antibacterial effect of several V/V solutions of commercially available insulin as well as the biofilm forming capacity for the following bacterial strains: Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, a clinical strain of Escherichia coli and a clinical strain of methicillin-resistant Staphylococcus aureus (MRSA). The results of our study showed that insulin detemir does not have any antibacterial capabilities for the four tested bacterial strains. The results also indicate that Staphylococcus aureus ATCC 25923 mixed with a V/V insulin detemir diluted suspension at all tested concentrations (from 10% to 10~8%) elevated biofilm formation while the other three tested strains showed no change in biofilm formation upon addition of insulin. This refers to a utilization process of the insulin detemir suspension from the three mentioned bacterial strains. From this it is evident that the effect different drugs have on the biofilm forming capacity of bacteria is significant in ordinating therapy for patients who take the drug of choice on a regular basis.