Publicaciones científicas SCI 1988
Considerations on the distribution of aflatoxigenic Aspergillus flavus in feeds
Mycopathologia 104(3):149-51.
The distribution of aflatoxin producing isolates of the Aspergillus flavus group in feeds was studied. Aflatoxin production was investigated by a sequential method previously reported (fluorescence in Coconut Agar Medium, rapid extraction from a wheat medium, and total extraction from the same wheat medium). Twenty-seven of 32 samples contained A. flavus, and 21 of them had at least one aflatoxicogenic isolate of A. flavus. Of the 115 isolates analysed, 65 produced aflatoxins, mainly B aflatoxins… Leer más
Moreno MA., Pro MJ., Olivares A. y Suarez G.
Assessment of different selective agar media for enumeration and isolation of Listeria from dairy products
The Journal Of Dairy Research 55(4):579-83.
Different selective agar media were compared for the recovery and isolation of five species of Listeria from raw milk and cheese. The selective media examined were Beerens medium, MacBride medium and that described by Dominguez et al. (1984) with 6 mg/l acriflavine, listeria selective agar medium (LSAM), and LSAM with 12 mg/l acriflavine (LSAM X 2A); a non-selective yeast glucose Lemco agar was included for comparison. When the difference between listeria and the natural microflora of raw milk and cheese was 10(2) cfu/ml, listeria could be isolated by direct plating on all media tested. When it was lower than 10(3)-10(4) cfu/ml, listeria were isolated by direct plating only on LSAM and LSAM X 2A. When the difference was greater than 10(4) c… Leer más
Dominguez L., Fernandez-Garayzabal JF., Briones V., Blanco JL. y Suarez G.
Immunocytochemical detection of Listeria monocytogenes in tissue with the peroxidase-antiperoxidase technique
Veterinary Pathology 25(5):385-7.
Listeria monocytogenes has been detected with the peroxidase-antiperoxidase (PAP) method on formalin-fixed,
paraffin-embedded organs from mice experimentally infected.6 The technique also has been successfully used to diagnose
natural avian listeriosis.8 Using this immunohistological
method we report the detection of L. monocytogenes in natural cases of encephalitis in sheep and cattle. The PAP method can be used as an aid to the routine diagnosis of listeriosis in these species, and a final etiological diagnosis can be established soon after the histopathological study.… Leer más
Marco A., Ramos JA., Dominguez L., Domingo M. y Gonzalez L.
Presence of aflatoxin M1 in commercial ultra-high-temperature-treated milk
Applied And Environmental Microbiology 54(6):1622-3.
Forty-seven samples of commercial ultra-high-temperature-treated milk from a dairy facility in the northwest part of Spain were analyzed for the presence of aflatoxin M1. A total of 14 samples (29.8%) were positive for aflatoxin M1 (4 in May, 3 in November, 3 in December, 1 in January, 1 in April, 1 in July, and 1 in August), 29 (61.7%) were negative, and 4 (8.5%) were doubtful, i.e., they showed trace quantities of aflatoxin M1. The range of aflatoxin M1 content was 0.02 to 0.1 ng/ml… Leer más
Blanco JL., Dominguez L., Gomez-Lucia E., Fernandez-Garayzabal JF., Garcia JA. y Suarez G.
Serological studies on Listeria grayi and Listeria murrayi
The Journal Of Applied Bacteriology 64(5):371-8.
A cross-agglutination study between somatic antigens from reference strains of Listeria grayi and Listeria murrayi with rabbit antisera was done. L. murrayi antisera reacted, at low titres, with L. grayi but L. grayi antisera did not react with L. murrayi antigen. These results, together with agglutinin-absorption tests, led to the conclusion that the serologic relationship between L. grayi and L. murrayi is not as close as is thought. The two species seem to differ in at least one somatic factor, that might be designated O-XVI for L. grayi and O-XVII for L. murrayi. The serologic relationship of L. grayi and L. murrayi with other serovars of Listeria is discussed. The agglutination titre of 180 healthy ruminants against O-antigens of L. gr… Leer más
Vazquez-Boland JA., Dominguez L., Fernandez-Garayzabal JF., Blanco JL., Gomez-Lucia E., Briones V. y Suarez G.
Experimental aflatoxin production in home-made yoghurt
Zeitschrift Für Lebensmittel-Untersuchung Und -Forschung 186(4):323-6.
Fungal growth and aflatoxin production by an aflatoxigenic strain during the manufacture of yoghurt are described. This completes previous studies which show that yoghurt may be a good substrate for aflatoxin production. Two factors were of special interest: (a) the temperature of the elaboration process (45 degrees C) and (b) the effect of lactic bacteria. Either during the elaboration of yoghurt or during its cooling from 45 degrees C to 4 degrees C, the necessary conditions required to start fungal growth are given; these are adequate enough for the synthesis of small quantities of aflatoxins. However our results do not clearly show that lactic bacteria have an influence on fungal growth and aflatoxin production… Leer más
Blanco JL., Dominguez L., Gomez-Lucia E., Fernandez-Garayzabal JF., Goyache J. y Suarez G.
Experimental aflatoxin production in commercial yoghurt
Zeitschrift Für Lebensmittel-Untersuchung Und -Forschung 186(3):218-22.
The production of aflatoxins in commercial yoghurt inoculated with Aspergillus parasiticus NRRL 2999 was studied, using different incubation conditions. In all of the experiments, the level of aflatoxins was higher at 28 degrees C than at 15 degrees C and higher in a "damaged" container than in an "intact" container (related to microaerophilic conditions). No fungal growth or aflatoxin production was seen at 10 degrees C. Both fungal growth and aflatoxin concentration vary throughout the incubation period instead of progressively increasing. The ratio of aflatoxin B and G (B:G) at 28 degrees C was almost 1:1, but generally more aflatoxin G was detected at 15 degrees C. The distribution in mycelium/substrate was approximately 1:1 at both 28 … Leer más
Blanco JL., Dominguez L., Gomez-Lucia E., Fernandez-Garayzabal JF., Goyache J. y Suarez G.
Experimental aflatoxin production in Manchego-type cheese
The Journal Of Applied Bacteriology 64(1):17-26.
Manchego-type cheese, a typical Spanish cheese, was inoculated in various ways with an aflatoxigenic organism, Aspergillus parasiticus NRRL 2999, to study the production of aflatoxin. When the original milk was contaminated with a spore suspension, aflatoxin was not detected in paraffin-covered cheeses although it was present in the top layer of non-paraffin-covered cheeses after ripening at 15 degrees C for 60 d. When the cheese surface was inoculated, no aflatoxins were detected in paraffin-covered cheeses after ripening for 60 d although they were found when the cheeses were ripened for 30 d. In non-paraffin-covered cheeses aflatoxins were detected only in the top layer and in the second 10 mm layer when cheeses were incubated after the … Leer más
Blanco JL., Dominguez L., Gomez-Lucia E., Fernandez-Garayzabal JF., Goyache J. y Suarez G.
Behaviour of aflatoxin during the manufacture, ripening and storage of Manchego type cheese
Journal Of Food Science 53(5):1373-1388.
The behavior of aflatoxins B1, B2, G1, G2, and M1 was investigated during manufacture, ripening, refrigeration, and frozen storage of Manchego-type cheese. More aflatoxins (per weight or volume) occurred in curd than in whey, although total quantity was greater in whey. Aflatoxins B1 B2, and M1 remained stable during ripening, but G1 and G2 levels increased. Concentration of B1, B2, and M1 decreased after 15 and 30 days refrigeration storage, but after 60 days 100% recovery occurred in the inner portion and only 60% in the outer. Concentrations of G1 and G2 also decreased during the first 30 days, but on day 60 an increase was observed, 200% in the inner and 120% in the outer portions. Aflatoxins were stable after 90 days in frozen storage.… Leer más
Blanco JL., Dominguez L., Gomez-Lucia E., Fernandez-Garayzabal JF., Goyache J. y Suarez G.
Immunohistologic diagnosis of avian listeriosis
Avian Pathology: Journal Of The W.V.P.A 17:227-233.
Listeriosis in a chicken from a small farm was diagnosed by the per-oxidase-antiperoxidase (PAP) method. The animal had diffuse myocarditis and necrotic foci in the liver and in the spleen. PAP technique performed on formalin-fixed tissues confirmed the presumptive diagnosis. Serological and microbiological studies were also done. It is concluded that PAP method is useful for the diagnosis of avian listeriosis allowing retrospective studies with formalin-fixed, paraffin-embedded tissues, avoiding cumbersome microbiological culture.… Leer más
Ramos JA., Domingo M., Dominguez L., Ferrer L. y Marco A.
