Comparison of the antibacterial activity of aqueous extract Hypericom and its microemulsion form on Gram-negative clinical strains

Hypercom perfuratum has medicinal properties in traditional medicine with antidepressant and anti-microbial effects. In this study, a new form of aqueous extract of Hypercom was prepared as a micro emulsion form, and its antimicrobial properties was investigated in comparison with ordinary aqueous extract on clinical strains of gram-negative bacteria.
Ten types of clinical strains were investigated in this work. Hypericum extract was prepared by water in boiling temperature and micro emulsion with the help of two types of emulsifiers. Antibacterial properties of the two materials were performed by determining the inhibition zone in a disk diffusion method and the measurement of minimum inhibitory concentrations (MIC) by the microplate dilution and a ELISA reader device.
Salmonella typhi has the highest zone of inhibition around 42 mm at a concentration of 8 mg/ml for extract and 30 mm in 0.1mg/ml micro emulsion but Pseudomonas had no zone. The MIC with microplate for Salmonella had greatest effect on the amount of 0.01563 mg/ml for Shigella concentration of 0.00625 mg/ml respectively. MIC for E. coli and Proteus extract 0.5 mg/ml and the microemulsion 0.025 mg/ml for both bacteria.
Comparison of Hypercom extract and its microemulsion form on gram negative bacteria confirmed that microemulsion in lower concentrations had the antibacterial effect equal to aqueous extract. The use of microemulsion of the extract was recommended in clinical study of herbal medicines.