33G-6 |
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T. GONZÁLEZ1, I. Guerrero2, A. González, and M. Zamudio. (1) Facultad de Ingeniería Química, Universidad Autónoma de Yucatán, Av. Juárez 421 Cd. Industrial, Mérida, Yucatán, 97288, Mexico, (2) Universidad Autónoma Metropolitana-Iztapalapa, México, D.F:, Mexico Probiotics are live microbial feed supplements which beneficially affect the host by improving its intestinal microbial balance. The probiotic activity of Lactic Acid Bacteria (LAB) has been emphasized in recent years. Although there are many products announced with probiotic activity in the market, not all of them are effective since they sometimes may lack the probiotic capacity or because this activity may also be influenced by the diet or the geographical region. The objective of the present study was to isolate LAB from different substrates of Yucatan, Mexico in order to characterize their in vitro probiotic activity for further suitable applications to indigenous population. In this work were obtained 110 pure strains of microorganisms and 82 of them displayed characteristics of LAB group. These LAB strains were examined for tolerance to acid (pH 2.5) and 0.3% oxgall, antimicrobial activities against enteric pathogenic bacteria and production of organic acids and hydrogen peroxide, finally some of the strains were identified with API 50CHL system. Most of the isolated strains can not tolerate and survived the acid conditions used, but grown well in presence of bile. In this test 19 strains, with tolerances similar to Lactobacillus johnsonii, were obtained; these also presented high antimicrobial activities against E. coli, S. aureus, Salmonella sp. and Shigella sp. Only four strains produce hydrogen peroxide, almost all the strains produces L (+)-lactic acid during glucose fermentation in amounts up to 200 mg/dL and none of them forms acetic, propionic, butyric or valeric acid. The lactic acid production is in the ranks reported for similar microorganisms. Most of the selected strains belong to Pediococcus genus (7), though the rest are Lactobacillus, Aerococcus and Enterococcus. All of the 19 selected strains display desirable characteristics for its use as probiotics. These results can be used to develop fermented functional traditional foods, with these microorganisms, for the indigenous population in order to diminish the rate of gastrointestinal diseases.
Session 33G, Nutraceuticals & Functional Foods: Lipid and probiotic functional foods
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