INVESTIGADORES
PATRIARCA Andrea Rosana
artículos
Título:
Ochratoxin A production by a mixed inoculum of Aspergillus carbonarius at different conditions of water activity and temperature
Autor/es:
STELLA MARIS ROMERO; VIRGINIA FERNÁNDEZ PINTO; ANDREA PATRIARCA; GRACIELA VAAMONDE
Revista:
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2010 p. 277 - 281
ISSN:
0168-1605
Resumen:
Growth rate, lag phase and OTA production of a mixed
inoculum of four Aspergillus carbonarius strains
were compared to the behaviour of the single strains at 30 °C on Czapek Yeast Extract
Agar. Significant differences between radial growth rates and lag phases of the
different isolates were observed; however, no significant differences between
growth rates of each strain and the mixed inoculum were detected. When the four
strains were inoculated simultaneously, the lag phase was the same than the
higher value obtained for individual strains, suggesting mycelial interactions
between the A. carbonarius isolates. The four strains differed in maximum OTA
yield, and the toxin accumulation by the mixed inoculum showed intermediate
levels at each time point. The effects of water activity (0.83, 0.85, 0.87,
0.89, 0.90, 0.93 and 0.95) and temperature (15, 20, 25, 30, and 35 °C) on OTA production by
the mixed inoculum were studied at 7, 14, 21 and 28 days of incubation. The
limiting water activity for OTA production by the mixed inoculum was 0.87,
showing xerotolerant behaviour of the strains isolated from dried vine fruits.
Results obtained were similar to those reported for single A. carbonarius strains from European countries, Israel, Australia
and South America. The similar trend in the response of the different isolates
to the variation of environmental parameters may be of interest for the
building of predictive models.