Inhibition of Antimicrobial Resistant Salmonella Heidelberg by a Synbiotic Combination of Prebiotics and Probiotics in an in Vitro Model (P20-011-19)

Abstract

Objectives: The aim of this study was to compare effects of different probiotic strains with and without prebiotics on lowering Salmonella heidelberg CFU in vitro. Methods: The different inhibition levels of three strains of probiotics, Bifidobacterium lactis (Danisco Bl-04), Lactobacillus rhamnosus (Danisco Lr-32TM) and Lactobacillus acidophilus (Danisco La-14) on S. heidelberg were assessed and compared in presence and absence of 2.5% prebiotic cocktail of mannose (Acros Organics), xylose (Fisher Scientific), and inulin (MP Biomedicals) using Mueller-Hinton agar wells diffusion (factorial experiment). Recommendations for growth of selected microorganisms such as temperature and oxygen conditions were taken into consideration. All the analysis was conducted in triplicates. Results: The results showed that three probiotics strains were able to significantly (P < 0.05) inhibit growth of S. heidelberg with and without prebiotics. Moreover, results showed that zones of inhibition were significantly (P = 0.03) greater with addition of prebiotics regardless of probiotic strains used. Conclusions: According to the Centers for Disease Control (CDC), salmonella causes about 1.2 million illnesses, 23,000 hospitalizations, and 450 deaths in US every year. S. heidelberg is a multidrug-resistant strain that has been associated with high risk of hospitalizations. Probiotics produce organic acids that lower pH of intestines thus inhibiting pathogenic microorganisms. Probiotics may be utilized in livestock feed to reduce the chance of any contamination before the materials undergo processing, thereby developing sustainable food products that are safe from farm to fork. Funding Sources: USDA-NIFA. Supporting Tables Images and/or Graphs: