title: Factors stimulating riboflavin produced by Lactobacillus plantarum CRL 725 grown in a semi-defined medium.
abstract: Riboflavin (vitamin B2) is one of the B-group water-soluble vitamins and is essential for energy metabolism of the cell. The aim of this study was to determine factors that affect riboflavin production by Lactobacillus (L.) plantarum CRL 725 grown in a semi defined medium and evaluate the expression of its rib genes. The factors found to enhance riboflavin production in this medium were incubation at 30 °C, and the addition of specific medium constituents, such as casamino acids (10 g L-1), guanosine (0.04 g L-1), and sucrose as carbon source (20 g L-1). In these conditions, higher riboflavin concentrations were directly associated with significant increases in the expression of ribA, ribB, and ribC genes. The culture conditions defined in this work and its application to a roseoflavin resistant mutant of L. plantarum allowed for a sixfold increase in riboflavin concentrations in our semi-defined medium which were also significantly higher than those obtained previously using the same strain to ferment soymilk. These conditions should thus be evaluated to increase vitamin production in fermented foods.
authors.affiliation: Centro de Referencia para Lactobacilos (CERELA-CONICET), Tucumán, Argentina.
authors.forename: Marianela
authors.initials: M
authors.lastname: Juarez Del Valle
authors.affiliation: Centro de Referencia para Lactobacilos (CERELA-CONICET), Tucumán, Argentina.
authors.forename: Jonathan Emiliano
authors.initials: JE
authors.lastname: Laiño
authors.affiliation: Centro de Referencia para Lactobacilos (CERELA-CONICET), Tucumán, Argentina.|Cátedra de Microbiología Superior, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Tucumán, Argentina.
authors.forename: Graciela
authors.initials: G
authors.lastname: Savoy de Giori
authors.affiliation: Centro de Referencia para Lactobacilos (CERELA-CONICET), Tucumán, Argentina.
authors.forename: Jean Guy
authors.initials: JG
authors.lastname: LeBlanc
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics; D003470:Culture Media / Q000737:chemistry; D005285:Fermentation; D005798:Genes, Bacterial; D006151:Guanosine / Q000378:metabolism; D048191:Lactiplantibacillus plantarum / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D009154:Mutation; D009713:Nucleotidyltransferases / Q000235:genetics; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics; D012256:Riboflavin / Q000096:biosynthesis*; D041942:Soy Milk / Q000378:metabolism; D013395:Sucrose / Q000378:metabolism
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D003470:Culture Media; C017721:casamino acids; D006151:Guanosine; D013395:Sucrose; C105392:RibC protein, bacteria; D017853:Phosphotransferases (Alcohol Group Acceptor); D009713:Nucleotidyltransferases; D012256:Riboflavin
keywords: chemically defined medium; lactic acid bacteria; rib gene expression; riboflavin; vitamin biosynthesis