SCI scientific publications 1986
Growth and enterotoxin A production by Staphylococcus aureus S6 in Manchego type cheese
The Journal Of Applied Bacteriology 61(6):499-503.
Milk (from cow, goat and sheep) was inoculated with Staphylococcus aureus strain S6, which is generally considered to be a strong enterotoxin B producer and a weak enterotoxin A producer. It was then used to make Manchego type cheese as prepared industrially. Two concentrations of starter culture (1% and 0.1%) were tested. Staphylococcal growth was good in both but better in the more dilute culture. Staphylococcal enterotoxin B was not detected at any stage of the ripening process of any cheese tested. However enterotoxin A was detected in both starter concentrations, reaching as high as 769 ng/100 g of cheese in the 0.1% starter batches… Leer más
Gomez-Lucia E., Blanco JL., Goyache J., de la Fuente R., Vazquez JA., Rodriguez EF. and Suarez G.
Aflatoxin-producing potential of Aspergillus flavus strains isolated from Spanish poultry feeds
Mycopathologia 95(3):129-32.
A total of 126 fungal strains belonging to the Aspergillus flavus group isolated from commercial poultry mixed feeds were studied. One hundred and twenty-five were identified as A. flavus and one as A. parasiticus. Forty nine strains (39%) produced aflatoxins on a crushed moist wheat medium (28 degrees C/10 days), whereas only sixteen (13%) showed specific fluorescence on Aflatoxin-Producing Ability Medium. In both media, mainly aflatoxins B1 and B2 were detected, the average concentration of aflatoxins being 4 294 +/- 1 083 micrograms/kg in crushed moist wheat medium, and 877 +/- 257 micrograms/kg in Aflatoxin-Producing Ability Medium… Leer más
Moreno MA. and Suarez G.
Minimal moisture content for growth and aflatoxin production by Aspergillus parasiticus in mixed feeds
Mycopathologia 95(3):145-8.
Minimal moisture content for growth and aflatoxin production by Aspergillus parasiticus in mixed feeds was studied. Minimal moisture content for growth is 16.51% +/- 0.45. Very low amounts of aflatoxins are accumulated at days 1 or 2 after the growth started when the initial moisture content of the mixed feed was 17% or lower; on the other hand, significant amounts of aflatoxin are detected when it was 18% or higher… Leer más
Moreno MA., Ramos MC., Rodriguez EF. and Suarez G.
Demonstration of Listeria monocytogenes with the PAP technique in formalin fixed and paraffin embedded tissues of experimentally infected mice
Zentralblatt Für Veterinarmedizin. Reihe B. Journal Of Veterinary Medicine. Series B 33(7):537-42.
This report describes the demonstration of Listeria monocytogenes in routinely formalin-fixed and paraffin-embedded tissues using the peroxidase-antiperoxidase (PAP) method. Liver and spleen of mice inoculated intraperitoneally with Listeria monocytogenes serotype 1/2 a showed focal necrosis which contained a large number of bacteria. A rabbit anti-Listeria monocytogenes serum reacted with bacteria in the foci of necrosis. No reaction was observed with other tissues from different species, which contained various known and unknown bacteria. This technique could be helpful in routine diagnosis and pathogenic studies of Listeriosis.… Leer más
Domingo M., Ramos JA., Dominguez L., Ferrer L. and Marco A.
Microplate technique to determine hemolytic activity for routine typing of Listeria strains
Journal Of Clinical Microbiology 24(1):99-103.
Because the hemolysis produced by Listeria monocytogenes and Listeria seeligeri on blood agar is frequently difficult to interpret, we developed a microplate technique for the routine determination of hemolytic activity with erythrocyte suspensions. This microtechnique is a simple and reliable test for distinguishing clearly between hemolytic and nonhemolytic strains and could be used instead of the CAMP (Christie-Atkins-Munch-Petersen) test with Staphylococcus aureus in the routine typing of Listeria strains. Furthermore, our results suggest that the quantitation of the hemolytic activity of the Listeria strains, along with the D-xylose, L-rhamnose, and alpha-methyl-D-mannoside acidification tests, allows the differentiation of L. monocyto… Leer más
Dominguez L., Vazquez-Boland JA., Fernandez-Garayzabal JF., Echalecu P., Gomez-Lucia E., Rodriguez-Ferri E. and Suarez G.
Listeria monocytogenes dans le lait pasteurisé
Canadian Journal Of Microbiology 32(2):149-150.
An haemolytic Listeria monocytogenes strain pathogenic to mice was isolated from 6 out of 28 (21.4%) pasteurized milk samples (3.2% fat milk treated at 78 degrees C for 15 s) marketed by a Madrid processing plant. Listeria grayi was recovered from 25 of the samples (89.2%) and L. innocua from 3 samples (10.7%). One milk sample was contaminated with L. welshimeri. No strains of L. ivanovii, L. seeligeri, L. murrayi, or L. denitrificans were isolated. These results show that pathogenic Listeria strains can be isolated from pasteurized milk and reinforce the hypothesis that this food product may be the source of numerous human listeriosis… Leer más
Fernandez-Garayzabal JF., Dominguez L., Vazquez-Boland JA., Blanco JL. and Suarez G.