Isolation of potential beneficial bacteria with proteolytic activity from poultry feed

QUIROGA, MARÍA; PEREZ CHAIA, ADRIANA; ARGAÑARAZ MARTINEZ, ELOY; BERTANI, MILENA SABRINA

Congreso; LII Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB 2016); 2016

Many bacteria possess proteases and peptidases active on proteins and peptides present in wheat, soybeans and other grains, so they could contribute to the production of aminoacids and small peptides in the gut of poultry, fed with cereals and seeds. With the aim of obtain proteolytic strains to be used as poultry feed supplements, different bacteria were isolated from meat meal, soybean meal and feed ready to eat provided by poultry farms. Colonies were obtained from selective media, and morphological characteristics, Gram stain, spore formation, catalase reaction and the response to several biochemical tests were assessed. Then a soybean protein isolate (SPI) was prepared and partially purified to evaluate the proteolytic activity of the isolates. SPI was used as the only source of protein in a modified culture medium. Considering all the results obtained we concluded that 26% of the isolated bacteria from feed and soybean meal belong to the genusLactobacilluswhile in meat meal this genus was not present. The genusEnterococcuswas at the same proportion, 19 %, in all the samples analyzed. The genusBacillusrepresented only 4 % of strains isolated from meals. Proteolytic activity was detected in 67% of strains of Lactobacillus, 78% ofEnterococciand in all theBacillus isolated. Further studies will be used for the selection of new supplements for poultry breeding.