Olga Lucia Mondragon-Bernal
University of Lavras, Brazil
Posters & Accepted Abstracts: Health Care Current Reviews
Resistance to drastic gastrointestinal tract (GIT) conditions is one prime functional characteristic of probiotic strains. Pure Lactobacillus rhamnosus (LR32) and with Lactobacillus paracasei sp (LBC81) strain was digested in enzymatic solutions (0.25%) at GITīs pH with or without soy extract (10%). Enzymatic tests were carried out in pH 6.0 (pepsin), pH 7.0 (lipase), pH 5.2 (lysozyme) and pH 2.0 (gastric juice) buffers. Controls without enzymes+soy extract were tested at pH 8.0, 7.0, 6.0 and 5.2. 1mL of pure LR32 or mixed LR32: LBC81 (1:1) was diluted in 9mL of the enzymatic solution. The digestion was made in the water bath at 37°C for 3h. pH2.0 was the one that most affected the resistance of the pure and mixed LR32. At 1h of digestion, the loss of viability was higher than 75% in all cases, a reduction was more than 6 log of the initial counts. The viability of LR32+soy at pH 2.0 and lysozyme reduced by 68% in 1h and in 3h the losses remained high. The lowest losses occurred at pHs 7.0, 6.0 and 5.2 with or without enzymes, in the first case, after 3h the viability reduction was 7.6%. With LR32+soy the viability lost 4.9% in pH 7.0 after 3h and with the control was 7.6%. At pH 6.0+pepsin, LR32+soy reduced by 68% in 3h and 12.5% with lysozyme (controls ranged between 79-22%). LR32+LBC81 after 3h and pH 7.0 without enzymes lost cells at 6.77%. Soy extract showed the protective effect for LR32 in GIT resistance. pH 2.0+pepsin were drastic for LR32 and LBC81 did not improve its resistance.
Olga Lucia Mondragon-Bernal is bachelor's at Food Engineering from the University of Bogota Jorge Tadeo Lozano (1994) in Bogota/Colombia, Master and Doctor in Food Engineering at State University of Campinas (2004 e 2009) in Campinas/Brazil. Worked in the food industry (1994-1998). She was a Professor in UPTC-Tunja/Colombia (1998-2001). She is currently Adjunct III Professor at the Federal University of Lavras at Department of Food Sciences. She has experience in Food bioengineering; functional foods developing; lactic fermentation; industrial microbiology; food analysis; syntropy, symbiosis, and synergy in bioprocesses; process optimization; food safety; and, assurance, control and quality in the food industry.
E-mail: olga@dca.ufla.br