Enterococcus faecium M7AN10 probiótico em matriz alimentar para cães / Enterococcus faecium M7AN10 probiotic in food matrix for dogs / Enterococcus faecium M7AN10 probiótico en matriz alimentaria para perros

Probióticos são capazes de melhorar o equilíbrio da microbiota intestinal, trazendo benefícios ao hospedeiro. Atualmente no mercado há poucas opções de alimentos, com probióticos em sua composição, destinados a cães e gatos. Portanto, o objetivo deste trabalho foi desenvolver uma matriz alimentar canina (ração úmida) com o probiótico Enterococcus faecium M7AN10. Para tal, avaliou-se a inocuidade, atividade enzimática, atividade antimicrobiana, potencial probiótico e a viabilidade do microrganismo em matriz alimentar canina. O isolado foi considerado inócuo, pois apresentou ausência de atividade hemolítica e de gelatinase, além de ser suscetível a diversos antimicrobianos. E. faecium M7AN10 apresentou atividade proteolítica e capacidade de produção de exoplissacarídeo. Em relação a atividade antimicrobiana pelo método da estria radial, o isolado inibiu Acinetobacter sp. 1, Corynebacterium sp. 4, Micrococcus luteus 33, Micrococcus luteus 43, Micrococcus sp. 3, Micrococcus sp. 20, Micrococcus sp. 36. Além disso, E. faecium M7AN10 apresentou capacidade de autoagregação de 33,50% e resistiu de forma constante quando submetido ao trato gastrointestinal in vitro em conjunto com Lacticaseibacillus rhamnosus LB 1.5 e Lacticaseibacillus paracasei LB 6.4. O cultivo misto manteve-se viável em matriz alimentar canina durante o período de oito dias. Com base nesses resultados, o isolado E. faecium M7AN10 foi considerada uma bactéria candidata a probiótico que pode vir a ser usada como aditivo em alimento para cães.

Probiotics are capable of improving the balance of the intestinal microbiota, bringing benefits to the host. Currently, on the market, there are few food options with probiotics in their composition intended for dogs and cats. Therefore, this research aimed to develop a canine food matrix (wet food) with the probiotic Enterococcus faecium M7AN10. To this end, the harmlessness, enzymatic activity, antimicrobial activity, probiotic potential, and viability of the microorganism in the canine food matrix were evaluated. The isolate was considered harmless, as it showed no hemolytic and gelatinase activity and was susceptible to several antimicrobials. E. faecium M7AN10 showed proteolytic activity and exopolysaccharide production capacity. Regarding antimicrobial activity using the radial stria method, the isolate inhibited Acinetobacter sp. 1, Corynebacterium sp. 4, Micrococcus luteus 33, Micrococcus luteus 43, Micrococcus sp. 3, Micrococcus sp. 20, Micrococcus sp. 36. Furthermore, E. faecium M7AN10 showed a self-aggregation capacity of 33.50% and resisted consistently when subjected to the gastrointestinal tract in vitro together with Lacticaseibacillus rhamnosus LB 1.5 and Lacticaseibacillus paracasei LB 6.4. The mixed culture remained viable in a canine food matrix over eight days. Based on these results, the isolate E. faecium M7AN10 was considered a candidate bacterium for a probiotic that could be used as an additive in dog food.

Los probióticos son capaces de mejorar el equilibrio de la microbiota intestinal, aportando beneficios al huésped. Actualmente en el mercado existen pocas opciones de alimentos con probióticos en su composición, destinados a perros y gatos. Por lo tanto, el objetivo de este trabajo fue desarrollar una matriz alimentaria canina (comida húmeda) con el probiótico Enterococcus faecium M7AN10. Para ello se evaluó la inocuidad, actividad enzimática, actividad antimicrobiana, potencial probiótico y viabilidad del microorganismo en matriz alimentaria canina. El aislado fue considerado inofensivo, ya que no mostró actividad hemolítica ni gelatinasa, además de ser susceptible a varios antimicrobianos. E. faecium M7AN10 mostró actividad proteolítica y capacidad de producción de exoplisacáridos. En cuanto a la actividad antimicrobiana mediante el método de las estrías radiales, el aislado inhibió a Acinetobacter sp. 1, Corynebacterium sp. 4, Micrococcus luteus 33, Micrococcus luteus 43, Micrococcus sp. 3, Micrococcus sp. 20, Micrococcus sp. 36. Además, E. faecium M7AN10 mostró una capacidad de autoagregación del 33,50% y resistió consistentemente cuando se sometió al tracto gastrointestinal in vitro junto con Lacticaseibacillus rhamnosus LB 1.5 y Lacticaseibacillus paracasei LB 6.4. El cultivo mixto permaneció viable en una matriz de alimento canino durante un período de ocho días. Con base en estos resultados, el aislado E. faecium M7AN10 se consideró una bacteria candidata para un probiótico que podría usarse como aditivo en la comida para perros.

Characterization of the antimicrobial activity produced by Bacillus sp. isolated from wetland sediment.

Bacteria of the genus Bacillus sp. present the potential for inhibiting various pathogens, making them a promising starting point in the search for new antimicrobial substances. In this study, bacteria were isolated from sediment samples from humid areas of a Natural Conservation Unit in the state of Rio Grande do Sul, Brazil. The isolate Bacillus sp. sed 1.4 was selected for production of antimicrobial activity, and was characterized by MALDI-TOF and 16S rDNA sequencing. Phylogenetic analysis showed that Bacillus sed 1.4 was closely related to Bacillus altitudinis and Bacillus pumilus. The cell-free supernatant was partially purified using ammonium sulfate precipitation, gel filtration chromatography (Sephadex G-200) and an ultrafiltration membrane. Partial purification resulted in specific activity of 769.23 AU/mg, with a molecular mass of approximately 148 kDa. This antimicrobial substance showed stability at 100°C for 5 min, and was inactivated by proteolytic enzymes. An antimicrobial effect against Listeria species was observed. Considering the importance of the Listeria genus in the area of food safety, this antimicrobial activity should be further explored, specifically in the field of dairy products and with a focus on food biopreservation studies.

Biological activity of bacteria isolated from wetland sediments collected from a conservation unit in the southern region of Brazil.

Wetlands are ecosystems rich in biodiversity and their ecological importance is recognized worldwide. Sediment samples were subjected to physical-chemical analysis and organic carbon content varied from 3.0% to 4.8%, the clay between 32 and 40%, silt with 41% and 43%, sand coarse varied between 6 and 11% and fine sand between 7 and 16%. The nitrogen values ​​varied from 0.25% to 0.48%, the pH from 5.4 to 7.5 and the humidity ​​varied from 44 to 56%. The selected isolates were evaluated for enzymatic properties and 64% showed positive results for amylase, 16% for gelatinase, 37% for lipase, 91% for protease and 2.7% for inulinase. Six bacterial isolates were selected for the overlapping assay and Bacillus sp. sed 2.2 showed inhibitory activity against Corynebacterium fimi NCTC 7547, and the antimicrobial substance was partially purified. The characterization of the substance was carried and the substance was stable at 100° C for up to 10 minutes and sensitive to the enzymes papain and trypsin. This substance was active against some species of Listeria, including Listeria monocytogenes ATCC 7644. The microorganims obtained from sediment samples were important sources of bioactive compounds, including enzymes and peptides, being a source of bioactive compounds to be studied.