Detection of the antibacterial activity of Lactobacillus CFS against Proteus bacteria

Abstract

Urinary tract infections are among the most common bacterial infections affecting humans, with Proteus species frequently identified as a primary cause. The increasing resistance of these bacteria to antibiotics has prompted the search for safe biological alternatives, such as probiotics. In this study, the antibacterial action of the cell-free supernatant obtained from Lactobacillus isolates was evaluated against Proteus spp. adjusted to 0.50 McFarland turbidity using the well diffusion technique. Out of 150 urine samples collected from patients showing UTI symptoms, 20 samples (13.3%) were confirmed positive for Proteus. The infection rate was highest among patients aged between 21 and 40 years, Pearson Chi-square p-value = 0.000, which is less than 0.05, (statistically significant), relationship between age groups and the isolation of Proteus isolates, whereas there was no statistically significant relationship (p = 1.000) between gender (male and female) and Proteus isolation Meanwhile, 200 specimens taken from both clinical sources (healthy urine and vaginal swabs) and non-clinical sources (fermented foods) yielded 20 Lactobacillus isolates (10%).  The supernatant of Lactobacillus exhibited a clear inhibitory effect on all Proteus isolates, forming inhibition zones ranging from 9 to 18 mm. Overall, these findings suggest the potential use of Lactobacillus supernatant as a natural suppressive agent against resistant Proteus strains in urinary tract infections.