Design an economic culture medium from industrial by-products for the development of probiotic poultry strains

BERTANI MILENA SABRINA; PEREZ CHAIA, ADRIANA; GARRO MARISA SELVA; GRANDE SONIA MARÍA MERCEDES

San Miguel de Tucumán

Simposio; V Simposio Internacional de Bacterias Lácticas; 2016

Centro de Referencia para Lactobacilos

Probiotic strains are frequently used for poultry feed, especially lactobacilli and enterococci selected for their potential beneficial properties in vivo. It is currently known that the type of nutrient and selective agents used in isolation media determine the development of strains, which have characteristic hydrophobicity patterns for each medium. Thus, it is suggested that such components may influence the expression of cell-wall glycoproteins and carbohydrates. The aim of this work was to study the effect of different culture media composition on growth rate, biomass production and of cell-surface properties of Lactobacillus and Enterococcus strains isolated from poultry intestine. Conventional culture media (LAPTg, MRS, CAm, PAP) were used as well as media specifically designed with by-product from local industries such as cream yeast (Cervecería y Maltería Quilmes), cane molasses (Estación Experimental Agroindustrial Obispo Colombres EEAOC), milk whey and cheese whey (Trancas, Tucumán). Three strains were tested: E. faecium LET 301, L. salivarius LET 201 and L. reuteri LET 210. They were inoculated in all media and incubated at 37°C. In all cases, biomass was determined by viable cell counts in agar media. Growth rate and cell-surface properties were also assessed. Hydrophobicity was evaluated by partition assay with three different solvents (toluene, p-xylene and n-hexadecane). Autoaggregation test was performed by measuring variations of OD600 nm of cellular suspensions every 1 h during 4 h. All strains showed similar or higher growth in alternative medium compared to control media (LAPTg for Enterococcus and MRS for lactobacilli). E. faecium LET 301 showed similar hydrophobicity in all media evaluated, showing a low hydrophobicity or non-hydrophobic character, whatever the solvent used. The hydrophobic character of L. salivarius LET 201 was medium and high when assayed toward p-xylene, and medium and low toward toluene and n-hexadecane, respectively. L. reuteri LET 210 presented low hydrophobicity in all solvents assay. None of the strains evaluated evidenced autoaggregation. These results demonstrate that the evaluated by-products from local industries can be successfully used as substrates in economic culture media for the development of poultry probiotics. Nevertheless, it must be taken into account that each strain has different nutritional requirements.