Inhibition of toxicogenic Bacillus cereus in rice-based foods by enterocin AS-48.
The antimicrobial effect of the broad-spectrum bacteriocin enterocin AS-48 against the toxicogenic psychrotrophic strain Bacillus cereus LWL1 has been investigated in a model food system consisting of boiled rice and in a commercial infant rice-based gruel dissolved in whole milk stored at temperatures of 37 degrees C, 15 degrees C and 6 degrees C. In food samples supplemented with enterocin AS-48 (in a concentration range of 20-35 mug/ml), viable cell counts decreased rapidly over incubation time, depending on the bacteriocin concentration, the temperature of incubation and the food sample. Enterotoxin production at 37 degrees C was also inhibited. Heat sensitivity of endospores increased markedly in food samples supplemented with enterocin AS-48: inactivation of endospores was achieved by heating for 1 min at 90 degrees C in boiled rice or at 95 degrees C in rice-based gruel. Activity of enterocin AS-48 in rice gruel was potentiated by sodium lactate in a concentration-dependent way.
Grande
Maria J
MJ
Area de Microbiología, Departamento de Ciencias de la Salud, Facultad de Ciencias Experimentales, Universidad de Jaén, Campus Las Lagunillas s/n, 23071-Jaén, Spain.
Lucas
Rosario
R
Abriouel
Hikmate
H
Valdivia
Eva
E
Omar
Nabil Ben
NB
Maqueda
Mercedes
M
Martínez-Bueno
Manuel
M
Martínez-Cañamero
Magdalena
M
Gálvez
Antonio
A
D001409:Bacillus cereus / Q000187:drug effects* / Q000254:growth & development; D001430:Bacteriocins / Q000494:pharmacology*; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D005511:Food Handling / Q000379:methods*; D006801:Humans; D007223:Infant; D007225:Infant Food; D007231:Infant, Newborn; D012275:Oryza / Q000382:microbiology*; D013696:Temperature; D013997:Time Factors
D001430:Bacteriocins; C107799:enterocin A; C466236:enterocin AS-48, Enterococcus faecalis