Antibacterial Effect of Arginine, Protamine, Aqueous Extracts of Green Tea, and Aloe Vera against Escherichia Coli

E. coli is one of the failure factors in the pulpectomy of primary and permanent teeth. It is also responsible for many infectious diseases in Humans. This study aimed to determine antibacterial effect of arginine, protamine, aqueous extract of green tea, and Aloe vera against Escherichia coli (E. coli).

Aqueous extract of green tea, Aloe vera, and protamine with a concentration of 400 mg/ml, and arginine at a concentration of 160 mg/ml were used in this experimental study. E. coli was cultured on Mueller-Hinton broth and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the test materials against this microorganism was determined using micro-dilution test. Sodium hypochlorite 2.5% was used as a positive control.

It was found that protamine had the highest antibacterial activity (with MIC and MBC 0.62 mg/mL) and aqueous extract of green tea showed the lowest antibacterial activity against E. coli (with MIC100 mg/ml and MBC 200 mg/ml). Positive control (sodium hypochlorite 2.5%) showed better antibacterial activity against E. coli compared to other test materials.

Apart from sodium hypochlorite, among the tested materials, protamine had the maximum effect and aqueous extract of aloe vera, arginine, and aqueous extract of green tea showed the lowest antibacterial effect against E. coli., respectively.