IN VITRO CHARACTERIZATION OF PROBIOTIC PROPERTIES AND ANTI-CAMPYLOBACTER ACTIVITY OF LACTOBACILLUS SPP. ISOLATED FROM POULTRY, FERMENTED FOODS AND HUMAN FAECES - M. Khan; A. A. Anjum; M. Nawaz; A. R. Awan (Journal of Animal and Plant Sciences, 2020)
The aim of the present study was to isolate and characterize indigenous lactobacilli targeting inhibition of Campylobacter jejuni. Lactobacilli (n=150) were isolated from poultry droppings (62), fermented foods (yogurt and pickles) (78) and human faeces (10). Selected isolates were identified to specie level by amplifying and sequencing their 16SrDNA universal primers. All isolates were screened for their anti-Campylobacter activity by well diffusion assay. Out of 150, 07 isolates (PL22, PL53, PL120, PL135, PL141, PL145 and PL149) had stable anti-Campylobacter activity at pH 7. Selected isolates (n=08) were further characterized for their tolerance to low pH and bile salts, antibiotic susceptibility, auto-aggregation and co-aggregation properties. All selected isolates had significant tolerance to low pH (>50% survival at pH 3), bile salts (0.3%), auto-aggregation and co-aggregation properties. Selected isolates were had no acquired resistance to penicillin, tetracycline, ampicillin and erythromycin. PL53, PL120 and PL149 showed significantly higher (p<0.05) reduction (> 3 log10) of Campylobacter jejuni ATCC 33291 in broth culture. It is concluded that L. gallinarum PL53, L. paracasei PL120 and L. gallinarum PL149 have probiotic properties and anti-campylobacter activity.
Keywords: journal article; Probiotics; Lactobacillus; Campylobacter; pH tolerance; antimicrobial activity