Comparison of the Inhibitory Effects of Antibiotics With That of Pistachio Skin Extract on Enteric Bacteria

Background: In spite of many advantages of modern medicine in comparison with traditional treatments, chemical therapeutic agents have side effects. Pistachio skin extract has antibacterial effects, but side effect has not been reported. Objectives: The aim of this study was to compare the effects of pistachio skin extract with that of antibiotics such as amoxicillin, tetracycline, cefixime and ciprofloxacin, on enteric bacteria collected from patients with gastroenteritis. Patients and Methods: Experimental method was used for this study. One hundred samples were taken from patients with gastroenteritis; then, the samples were characterized and the diagnosis was made. The pistachios internal soft skin extracts were obtained, using the decoction method and water as the solvent. Afterwards, the solution was crystallized and placed on 37?C and its water has been evaporated. The solution required two days for the entire water loss process. Antibacterial effect of the extract was analyzed with the disc diffusion method using Mueller-Hinton agar medium. After steeping the blank disc in the extract, bacteria reached 0.5 McFarland density, were cultured on plates with four antibiotic discs including amoxicillin, tetracycline, cefixime and ciprofloxacin. Next, depending on the type of bacteria, the inhibition zones were compared to determine the antibiotic inhibitory effects. Statistical analysis for comparing the antibiotics and pistachio skin extract effects was performed using chi-square tests. Results: Shigella with 19% sensitivity and 1% resistance had the highest sensitivity and the lowest resistance to each of the antibiotics, including tetracycline, amoxicillin and ciprofloxacin; this difference was statistically significant (P < 0.05). The results showed that Escherichia coli with 13.6 mL sensitivity and 6.4 mL resistancy was the bacteria, for which antibiotics were least effective (amoxicillin: P = 0.000, tetracycline: P = 0.049, cefixime: P = 0.000); this finding was statistically significant (P < 0.05). Conclusions: Regarding the natural therapeutic effects of pistachio skin extract and obligations of the routine antibiotics such as resistancy, using pistachio extract as a co-therapeutical agent with ordinary antibiotics can enhance the success rate of the treatment