INCREASED RIBOFLAVIN CONCENTRATION IN MILK THROUGH FERMENTATION WITH SELECTED LACTIC ACID BACTERIA

JUAREZ DEL VALLE, M; LAIÑO, J; SAVOY DE GIORI, G; LEBLANC, JG

Horco Molle, San Miguel de Tucumán

Jornada; XXIX Jornadas Científicas de la Asociación de Biología de Tucumán; 2012

Asociación de Biología de Tucumán

Riboflavin (vitamin B2) plays an important role in cellular metabolism and is the precursor of the coenzymes FMN and FAD that participate in numerous oxidation-reduction reactions and energy metabolism. In this work, lactic acid bacteria (LAB) able of produce vitamin B2 in milk were identified. 180 strains, belonging to the collection of CERELA, were inoculated in a riboflavin-free synthetic medium and incubated at 37ºC for 16 h. The concentration of riboflavin was determined by means of a microbiological method using as reference strain Lactobacilus (L.) rhamnosus ATCC7469. Only 43 strains were able to grow in this medium. Of these, 12 strains were selected because their high production of riboflavin; L. plantarum (2), L. reuteri (2), L. fermentum (2), L. paracasei (2), L. bulgaricus (2), Lactococcus lactis (1) and Streptococcus thermophilus (2); and were inoculated in cow´s milk and incubated at 37°C for 24h. Some of the strains were able to increase up to 20% the vitamin concentrations in milk with respect to its initial concentration, whereas others decreased B2 concentrations. LAB capable of synthesizing riboflavin in milk constitutes a biotechnology strategy for the elaboration of novel vitamin bio-enriched foods.