CERELA   05438
CENTRO DE REFERENCIA PARA LACTOBACILOS
Unidad Ejecutora - UE
artículos
Título:
CULTURE MEDIA DESIGN FOR SCREENING OF BIOGENIC AMINE PRODUCING LACTIC ACID BACTERIA
Autor/es:
SAVINO M.J.; ARENA M. E.; MANCA DE NADRA M. C
Revista:
BIOCELL
Editorial:
INCA
Referencias:
Lugar: Mendoza-Argentina; Año: 2007 vol. 31 p. 301 - 301
ISSN:
0327-9545
Resumen:
Biogenic amines (BA),
organic bases, generated by microorganisms could spoilage fermented foods. BA
are measured by complex and expensive techniques, for this reason is important
to set a reliable method for detection of lactic acid bacteria (LAB) that produce
BA. The objective was to design a culture media that allows a qualitative
detection of LAB isolated from apples that produce tyramine (tyra) from
tyrosine (tyr). Two culture media were assayed: Media 1 (M1) in g/l: peptone, 5; yeast, 3; glucose (glc) 0.5;
tomato juice, 2%v/v; bromocresol green, 0.04%; Media 2 (M2): peptone and yeast
were not modified; glc, 1 g/l; tomato juice 5%v/v, bromocresol purple,
0.04%. The cultures media were added
with tyr 1g/l, pyridoxal phosphate, 0.006 g/l; two initial pH values were
tested: 4.5 and 5.2. Tyra was quantified by HPLC. In the first 5 days
incubation pH indicators showed an acidification. The production of BA is
indicated by media alkalization changing the colour media (M1). This fact was
observed after 5 days incubation for strains 44, 66, 68 of L. plantarum and 37, 72 of L.
brevis, at both pH. In M2 persisted yellow colour during the 10 days
incubation. Tyr decarboxylase activity was corroborated for the strains 44 and
72 of L. plantarum. The initial pH
did not modify the results. The design M1 appears to be a simple method to
detect LAB that produce tyr.