Strenuous physical activity, sleep deprivation, and psychological stress are common features of military field training. This study aimed to evaluate the effects of supplementation with a synbiotic ice cream on salivary IgA, gastrointestinal symptoms, well-being indicators, and gut microbiota in young military participants undergoing field training. Sixty-five military completed the study: one group was supplemented for 30 days with synbiotic ice cream containing: 2.1x108 CFU/g for L. acidophilus LA-5 and 2.7x109 CFU/g for B. animalis BB-12 and 2.3g of inulin in the 60g of ice cream at manufacture, and the other with a placebo ice cream. Volunteers were evaluated at pre-supplementation (baseline), post-supplementation, and after a five-day military training. Bifidobacterium and Lactobacillus genera were measured in stool samples and both showed a higher differential abundance post-supplementation and training. Salivary IgA and gastrointestinal symptoms decreased at post-training in both groups (p<0.05; main effect of time); however, supplementation with synbiotic did not mitigate this effect. Tenseness and sleepiness were decreased in the synbiotic-treated group, but not in the placebo group at post-military training (p=0.01 and p=0.009, respectively; group x time effect). The other well-being indicators were not affected by the synbiotic supplementation. In conclusion, 30 days of synbiotic ice cream supplementation containing inulin, L. acidophilus LA-5, and B. animalis BB-12 favourably modulated gut microbiota and improved tenseness and sleepiness in healthy young military undergoing a 5-day field training. These improvements may be relevant to this population as they may influence the decision-making process in an environment of high physical and psychological stress.

This research evaluated the functional potential of a fermented milk made with Streptococcus thermophilus, a probiotic (Bifidobacterium animalis subsp. lactis) and pomegranate juice. Ferric-reducing antioxidant potential, Trolox equivalent antioxidant capacity, scavenging effect on 1,1-diphenyl-2-picrylhydrazyl free radical, oxygen radical absorbance capacity and Folin-Ciocalteu assays were used to estimate antioxidant activity and phenolic content. Probiotic survival, release and absorption of polyphenols were evaluated using in vitro gastrointestinal digestion. The concentration of polyphenols increased during digestion from 608 mg to 1417 gallic acid equivalents (GAE) /L. About 14% of polyphenols were found on the dialysate portion. The beverage presented high viability of probiotics with high survival rate after digestion (above 7 log cfu/mL).

O exercício físico de alta intensidade está relacionado com diversas alterações sistêmicas que podem prejudicar a performance do indivíduo, tais como: a queda da imunidade, a perda de massa muscular, a insônia, entre outros. Os probióticos, quando administrados regularmente para esse público, podem reduzir os sintomas relacionados ao overtraining. O presente estudo buscou selecionar uma cepa probiótica para empregar em uma bebida esportiva (a base de leite fermentado), contendo elevada quantidade de compostos fenólicos e adicionada de cepas probióticas, sendo utilizadas como principal critério de escolha a sobrevivência da mesma após digestão simulada. Foram avaliados os probióticos Lactobacillus casei (BGP93), Lactobacillus rhamnosus (SP1) e Lactobacillus acidophilus (LA3) e Bifidobacterium animalis subsp. lactis (BB12), utilizando-se como cultura starter o Streptococcus thermophilus (TA072). Em paralelo foi realizada avaliação da resistência das culturas probióticas em solução adicionada de suco de romã, tendo em vista a potencial atividade antimicrobiana desta fruta. Neste teste foi observado que as culturas probióticas não foram inibidas pelo suco de romã, com exceção do L. acidophilus LA3. Para digestão in vitro foi utilizado protocolo validado composto pelas fases gástrica e entérica, a viabilidade dos probióticos na bebida esportiva foi acompanhada durante armazenamento refrigerado a 6 °C por 28 dias e a sobrevivência foi avaliada, por meio de contagem seletiva em DeMan, Rogosa & Sharpe (MRS) ágar acidificado e incubação em anaerobiose. Os resultados demonstraram que o Lactobacillus casei cepa BGP93 apresentou adequada viabilidade durante o armazenamento e maior taxa de sobrevivência à digestão, quando comparado aos demais probióticos, representando um bom candidato para a elaboração da bebida esportiva. Palavras chave: Leite Fermentado. Compostos Fenólicos. Alimento Funcional. Viabilidade de Probióticos.    Abstract High-intensity physical exercise is related to several systemic alterations that may impair the individual's performance, such as immunity depletion, muscle mass loss, insomnia, among others. Probiotics, when given regularly to this public, may reduce symptoms related to overtraining. The present study aimed to select a probiotic strain for use in a sports drink (based on fermented milk) containing a high amount of phenolic compounds, and added probiotic strains, being the main criterion of choice the survival of the strain after simulated digestion. The probiotics Lactobacillus casei (BGP93), Lactobacillus rhamnosus (SP1) and Lactobacillus acidophilus (LA3) and Bifidobacterium animalis subsp. lactis (BB12), using as starter culture Streptococcus thermophilus (TA072). At the same time, resistance evaluation of probiotic cultures in pomegranate juice solution was carried out, considering the potential antimicrobial activity of this fruit. In this test, it was observed that probiotic cultures were not inhibited by pomegranate juice, except for L. acidophilus LA3. For in vitro digestion a validated protocol consisting of gastric and enteric phases was used, the viability of probiotics in the sports drink was monitored during cold storage at 6 ° C for 28 days and survival was evaluated by selective counting in acidified DeMan, Rogosa & Sharpe (MRS) agar and incubation in anaerobiosis. The results showed that Lactobacillus casei strain BGP93 showed adequate viability during storage and higher survival rate to digestion when compared to other probiotics, representing a good candidate for the sport drink preparation Keywords: Fermented Milk. Phenolic Compounds. Functional Food. Probiotics Viability.