RESUMO
A Mexican staple food prepared with corn "tortilla" (Zea mays L.) and common beans (Phaseolus vulgaris L.) is named as "taco". It was fermented in an in vitro colonic Simulator of Human Microbial Ecosystem (SHIME®) to evaluate the effect in short chain fatty acids (SCFA), ammonia production, and the growth of total presumptive counts for anaerobic bacteria, Lactobacillus spp., Bifidobacterium spp., Clostridium spp., and total coliforms in the three simulated reactors of the human colon. After two weeks of stabilization, the simulator was fed during 9â¯days with the mixture of 50â¯g of beans and 50â¯g of tortilla mixed with 100â¯mL of carbohydrate based medium. Every third day, samples were collected from the three simulated colon vessels for the corresponding analysis. The production of the SCFA was higher during the treatment period than the basal period in the three colon sections. The acetate was produced in higher concentration (191.9â¯mmol/L) than propionate and butyrate (29.1 and 55.0â¯mmol). During the treatment period, the higher molar ratio (%) for acetate, propionate, and butyrate were 84: 14: 24, respectively. The ammonia ions as well as the growth of presumptive coliforms were reduced (pâ¯<â¯0.05) in the three simulated colon vessels during the treatment. Finally, in vitro fermentation of Mexican "taco" showed a possible potential functional profile of an ancestral staple food due to the production of SCFA that may exert beneficial effects.
Assuntos
Pão/análise , Colo/metabolismo , Colo/microbiologia , Fabaceae/química , Fermentação , Microbioma Gastrointestinal/fisiologia , Zea mays/química , Acetatos/metabolismo , Amônia/análise , Bifidobacterium , Butiratos/metabolismo , Clostridium , Ecossistema , Ácidos Graxos Voláteis/análise , Bactérias Gram-Negativas , Humanos , Lactobacillus , Propionatos/metabolismoRESUMO
BACKGROUND: Some probiotic strains have the potential to assist in relieving the symptoms of inflammatory bowel disease. The impact of daily ingestion of a soy-based product fermented by Enterococcus faecium CRL 183 and Lactobacillus helveticus 416 with the addition of Bifidobacterium longum ATCC 15707 on chemically induced colitis has been investigated thereof within a period of 30 days. METHODS: Colitis was induced by dextran sulfate sodium. The animals were randomly assigned into five groups: Group C: negative control; Group CL: positive control; Group CLF: DSS with the fermented product; Group CLP: DSS with the non-fermented product (placebo); Group CLS: DSS with sulfasalazine. The following parameters were monitored: disease activity index, fecal microbial analyses, gastrointestinal survival of probiotic microorganisms and short-chain fatty acids concentration in the feces. At the end of the protocol the animals' colons were removed so as to conduct a macroscopical and histopathological analysis, cytokines and nitrite quantification. RESULTS: Animals belonging to the CLF group showed fewer symptoms of colitis during the induction period and a lower degree of inflammation and ulceration in their colon compared to the CL, CLS and CLP groups (p<0.05). The colon of the animals in groups CL and CLS presented severe crypt damage, which was absent in CLF and CLP groups. A significant increase in the population of Lactobacillus spp. and Bifidobacterium spp. at the end of the protocol was verified only in the CLF animals (p<0.05). This group also showed an increase in short-chain fatty acids (propionate and acetate). Furthermore, the intestinal survival of E. faecium CRL 183 and B. longum ATCC 15707 in the CLF group has been confirmed by biochemical and molecular analyzes. CONCLUSIONS: The obtained results suggest that a regular intake of the probiotic product, and placebo to a lesser extent, can reduce the severity of DSS-induced colitis on rats.