IDENTIFICATION OF VITAMIN B2 PRODUCING STRAINS OF LACTIC ACID BACTERIA FOR THE DESIGN OF NOVEL BIO-ENRICHED FERMENTED FOODS

LAIÑO J; LEBLANC JG; SAVOY G

Tafi del Valle, Tucuman

Jornada; XXVII Jornadas Científicas de la Asociación de Biología de Tucumán.; 2010

Asociación de Biología de Tucumán.

Riboflavin (vitamin B2) is involved in energy metabolism, and is an integral component of the coenzymes (FAD) and flavin mononucleotide (FMN). Vitamin B2 deficiency is common in many parts of the world. The aim of this study was to examine native lactic acid bacteria (LAB) belonging to Lactobacillus (Lb.) bulgaricus (22 strains), Lb. rhamnosus (1), Streptococcus (St.) thermophilus (21) and Lactococcus (Lc.) lactis (1) to identify strains that have the capability to produce riboflavin. The growth in absence and presence of B2, and concentration of extracellular, intracellular and total B2 were evaluated. Vitamin concentration was determined by the microbiological assay technique using Lb. rhamnosus ATCC7469 as the test organism. Approx. 50% of the LAB (12 Lb. bulgaricus, 8 St. thermophilus and 1 Lc. lactis) grew in absence of B2 and produced a mean total concentration of 40.0 ± 0.1mg B2/l. St. thermophilus CRL1766, Lb. bulgaricus CRL543 and CRL865 secreted significant amounts of B2 (>80.0 ±0.1mg/l), whereas St. thermophilus CRL417 retained the highest vitamin concentration (63.4 ± 0.1mg/l). The results show the presence of wild-type strains of LAB able to produce and secrete B2 in significant amounts allowing their use in the design of riboflavin bio-enriched fermented products.