Effect of inoculants combining Lactobacillus buchneri strain LN40177 in different strata of the silo

The objective of this work was to evaluate the chemical composition and rumen disappearance rate of dry matter of corn silages with inoculants combining L. buchneri strain LN40177 in different strata of the silo. The experimental design was a 3x2 randomized complete block design, with three treatments: Control: corn silage without inoculant; 11CFT: corn silage with inoculant which combines L. buchneri strain LN40177 (1.1 x 1011 CFU g-1 ) with L. casei (1.1 x 1011 CFU g-1 ); and 11C33: corn silage with inoculant which combines L. buchneri strain LN40177 (1.1 x 1011 CFU g-1 ) with L. plantarum (1.1 x 1011 CFU g-1 ) and Enterococcus faecium (1 x 1010 CFU g-1 ), associated with two strata of the silo (lower and upper). The silage inoculated with 11C33 presented higher contents of crude protein and NDF and lower hemicellulose content in relation to the control treatment and 11CFT. The use of both inoculants resulted in silages with higher concentrations of soluble nutrients. Lower stratum silage had a higher rumen disappearance rate of dry matter compared to the upper stratum. In general, the combinations of L. buchneri promoted nutritional improvements in corn silage, but in presence of L. casei, there were more outstanding improvements.(AU)

Effect of inoculants combining Lactobacillus buchneri strain LN40177 in different strata of the silo

The objective of this work was to evaluate the chemical composition and rumen disappearance rate of dry matter of corn silages with inoculants combining L. buchneri strain LN40177 in different strata of the silo. The experimental design was a 3x2 randomized complete block design, with three treatments: Control: corn silage without inoculant; 11CFT: corn silage with inoculant which combines L. buchneri strain LN40177 (1.1 x 1011 CFU g-1 ) with L. casei (1.1 x 1011 CFU g-1 ); and 11C33: corn silage with inoculant which combines L. buchneri strain LN40177 (1.1 x 1011 CFU g-1 ) with L. plantarum (1.1 x 1011 CFU g-1 ) and Enterococcus faecium (1 x 1010 CFU g-1 ), associated with two strata of the silo (lower and upper). The silage inoculated with 11C33 presented higher contents of crude protein and NDF and lower hemicellulose content in relation to the control treatment and 11CFT. The use of both inoculants resulted in silages with higher concentrations of soluble nutrients. Lower stratum silage had a higher rumen disappearance rate of dry matter compared to the upper stratum. In general, the combinations of L. buchneri promoted nutritional improvements in corn silage, but in presence of L. casei, there were more outstanding improvements.

Effect of Lactobacillus sp. isolates supernatant on Escherichia coli O157: H7 enhances the role of organic acids production as a factor for pathogen control / Efeito do sobrenadante de isolados de Lactobacillus sp. sobre Escherichia coli O157: H7 reforça o papel da produção de ácidos orgânicos como fator de controle patogênico

Many attempts have been made to establish the control of foodborne pathogens through Lactobacillus isolates and their metabolism products with success being obtained in several situations. The aim of this study was to investigate the antagonistic effect of eight Lactobacillus isolates, including L. casei subsp. pseudoplantarum, L. plantarum, L. reuteri and L. delbrueckii subsp. delbrueckii, on the pathogenic Escherichia colistrain O157:H7. The inhibitory effect of pure cultures and two pooled cultures supernatants of Lactobacillus on the growth of pathogenic bacteria was evaluated by the spot agar method and by monitoring turbidity. Antimicrobial activity was confirmed for L. reuteri and L. delbrueckii subsp. delbrueckii and for a pool of lactic acid bacteria. The neutralized supernatant of the pool exerted a higher antimicrobial activity than that of the individual strains. Furthermore, D-lactic acid and acetic acid were produced during growth of the Lactobacillus isolates studied.(AU)

Muitas tentativas têm sido feitas para se estabelecer o controle de patógenos de origem alimentar através do uso de estirpes de Lactobacillus e dos seus produtos de metabolismo, com sucesso sendo sucedido em várias situações. O objetivo deste trabalho foi investigar o efeito antagônico do sobrenadante de culturas de oito isolados de Lactobacillus, incluindo L. casei subsp. pseudoplantarum, L. plantarum L. reuteri e L. delbrueckii subsp. delbrueckii, sobre Escherichia coli amostra O157:H7. Os efeitos inibidores de culturas puras e de dois "pools" de cultura de Lactobacillus sobre o crescimento da bactéria foram avaliados através do método de inibição em ágar e através do monitoramento da turbidez da cultura bacteriana. A atividade antimicrobiana foi confirmada para Lactobacillus reuteri e Lactobacillus delbrueckii subsp. delbrueckii e para o "pool" de bactérias acido-láctica. O sobrenadante neutralizado do "pool" de Lactobacillus exerceu uma atividade antimicrobiana mais elevada do que aquela das estirpes individuais. Além disso, ácido D-láctico e ácido acético foram produzidos durante o crescimento dos Lactobacillusestudados.(AU)