Production of Organic Acids by Probiotic Lactobacilli Can Be Used to Reduce Pathogen Load in Poultry

Abstract

Probiotic Lactobacillus can be used to reduce the colonization of pathogenic bacteria in food animals, and therefore reduce the risk of foodborne illness to consumers. As a model system, we examined the mechanism of protection conferred by Lactobacillus species to inhibit C. jejuni growth in vitro and reduce colonization in broiler chickens. Possible mechanisms for the reduction of pathogens by lactobacilli include: 1) stimulation of adaptive immunity; 2) alteration of the cecal microbiome; and, 3) production of inhibitory metabolites, such as organic acids. The Lactobacillus species produced lactic acid at concentrations sufficient to kill C. jejuni in vitro. We determined that lactic acid produced by Lactobacillus disrupted the membrane of C. jejuni, as judged by biophotonics. The spectral features obtained using Fourier-transform infrared (FT-IR) and Raman spectroscopy techniques were used to accurately predict bacterial viability and differentiate C. jejuni samples according to lactic acid treatment. FT-IR spectral features of C. jejuni and Lactobacillus grown in co-culture revealed that the metabolism was dominated by Lactobacillus prior to the killing of C. jejuni. Based on our results, the development of future competitive exclusion strategies should include the evaluation of organic acid production.

Intestinal lactic acid bacteria from Muscovy duck as potential probiotics that alter adhesion factor gene expression

“…The use of probiotics sourced from indigenous microbiota could prevent pathogenic colonization in the digestive tract and act as a barrier against toxic substances and pathogens (Long and Swenson, 1977;Nemcova, 1997;Zoetendal et al, 2006;Neal-McKinney et al, 2012). Previous studies show that lactic acid bacteria (LABs) and related microorganisms initially colonize the intestinal tract and subsequently, prevent colonization of intestinal pathogens (Long and Swenson, 1977).…”

Edible mushroom powder (Agaricus bisporus) and flavophospholipol improve performance and blood parameters of broilers

“…Giannenas et al (2010) reported that A. bisporus has a prebiotic-like effect on turkeys since fermentable polysaccharide content in mushrooms may improve growth of Lactobacilli and Bifidobacteria populations and inhibit E. coli leading to a more balanced biota population in the gastrointestinal tract of poultry, as a consequence, to a greater efficiency in digestibility and feed utilization. Furthermore, Lactobacilli may produce organic acids such as lactic acid (Rehman et al, 2007) and bactericidal substances (Neal-McKinney et al, 2012) that may improve gastrointestinal function and feed digestibility, resulting in enhanced growth and improved FCR (Ferket, 2004). …”

Three New Lactobacillus plantarum Strains in the Probiotic Toolbox against Gut Pathogen Salmonella enterica Serotype Typhimurium

“…It seems that low pH of Lactobacillus CFS is most likely responsible for the inhibition of S. Typhymurium growth. The antimicrobial eff ect of organic acids has been observed when using several Lactobacillus species (26,36). The growth-inhibiting activity of diff erent probiotic bacteria against pathogens such as Gram-negative S. Typhimurium, E. coli or Campy lo bacter jejuni, and Gram-positive bacteria Enterococcus faeca lis and Clostridium diffi cile was att ributed to a pH reduction and/or to the production of organic acids (37).…”