Antimicrobial Effects of Garlic (Allium sativum) on Albino Rats Experimentally Infected with Escherichia coli

Abstract

Escherichia coli is among the most prevalent bacterial species that cause food-borne diseases, gastroenteritis, urinary tract infections, and septicemia. The rising incidence of antibiotic-resistant strains of E. coli has become a matter of great concern, especially in the developing world where antibiotics are misused. This has led to renewed interest in medicinal plants that possess antimicrobial properties. Garlic (Allium sativum) is well-documented for its broad antimicrobial activity that is mainly attributed to sulfur-containing compounds such as allicin, ajoene, and diallyl sulfides. The current study was undertaken to determine the antimicrobial efficacy of orally administered garlic decoction in albino rats infected with Escherichia coli. An experimental study was conducted using albino rats infected with E. coli. The animals were treated with oral administration of garlic decoction at 3.2 ml/kg and 9.6 ml/kg. The control group received amoxicillin (27.14 mg/kg), while the negative control group was left untreated. The bacterial load was estimated before treatment, immediately after treatment, and at the end of treatment. Analysis of variance (ANOVA) was used to analyze the results with a Games-Howell post hoc comparison test. The significance threshold was set at P < 0.05. Garlic decoction was found to have significant antimicrobial activity against E. coli infection. The treatment regimens were associated with progressive decreases in the bacterial load (P < 0.001). The 3.2 ml/kg dose regimen was associated with a reduction of the bacterial load from 37.68 ± 7.10 CFU/ml to 0.00 ± 0.00 CFU/ml at the end of treatment. The 9.6 ml/kg dose regimen was associated with a rapid decrease in the bacterial load from 35.59 ± 7.90 CFU/ml to 6.34 ± 8.00 CFU/ml immediately after treatment followed by complete clearance of the organism. Amoxicillin cleared the organism immediately after treatment, while the untreated control animals showed a marked increase in the bacterial load. Garlic decoction was found to be highly effective against E. coli infection in an animal model. The antimicrobial activity was dose-dependent and comparable to that of standard antibiotic therapy, especially with prolonged treatment. The current findings demonstrate the therapeutic potential of garlic in the treatment of infections caused by E. coli. Further studies to evaluate the phytochemical composition, pharmacokinetic properties, and toxicity profile are needed before clinical applications can be considered.