Tejuino: bebida típica mexicana com potencial probiótico

Abstract

Fermentation increases nutritional value by essential amino acids, vitamins and other compounds synthesis, besides that, also preserves the food. Moreover, the microorganisms responsible for fermentation and in the food, still viable, can bring benefits to humans, showing probiotic characteristics. Cereals, on the other hand, are nondigestible carbohydrates sources that act as prebiotics. Therefore, the fermentation of cereals, combined with probiotic microorganisms use, consist in an area of interest for new functional foods investigation. In Mexico, there are several traditional fermented products from corn, including tejuino. This study was performed in order to select potential probiotic bacteria from tejuino. Initially, 81 bacteria that were isolated and identified from tejuino passed for selection based on two main criteria: no pathogenicity and consist of new species with potential probiotic. The 11 selected bacteria were adapted to the temperature of 37 ° C, crucial to the success of the following analysis. Those that best adapted were Leuconostoc citreum, Weissella cibaria, Chryseobacterium bovis and Bacillus safensis. The bacteria were grown in their respective culture media until reaching a population of Log 8-9 cfu / ml and inoculated separately in equipment that simulates the human gastrointestinal tract (automatic robotic intestinal system, ARIS), first with 0.9% saline and then with simulated "food". The bacteria recovered at this stage were subjected to pathogen inhibition test (Salmonella typhimurium, Salmonella typhimurium isolated from chicken, Staphylococcus aureus and Listeria monocytogenes) by Kirby-Bauer technique and evaluated for production of fatty acids of short chain by HPLC and the cells ability to adhere to HT-29. The species were confirmed by molecular techniques at the end of the experiment. he bacteria L. citreum, and W. cibaria survived the passage through the simulator (7 and 6 Log UFC/mL recovered at the end, respectively) and showed good results in the Probiotics in vitro tests. Both were able to inhibit the tested pathogens and analysis of fatty acid profiles showed the production of propionic and butyric acids that are involved in improving the health and consumer welfare. The ability to adhere to colorectal adenocarcinoma cells was observed only for L. citreum (approximately 25% of adherence) while W. cibaria not reached 1%. Thereby, the tejuino beverage has not only great culture value, but also nutritional, since it can be treat as a probiotic food and has the presence of bacteria with potential probiotic.