Biomedical subjects

G Szita

Publications and source records attributed to G Szita.

9 recordsLinked to original sources

PubMed1998

A novel, selective synthetic acetamide containing culture medium for isolating Pseudomonas aeruginosa from milk.

A selective synthetic medium has been developed both in liquid (Z-broth) and solid (Z-agar) forms for selective isolation of Pseudomonas aeruginosa from foods. The simple, easy to prepare peptone-free synthetic medium contained acetamide that is metabolized to ammonia and acetic acid providing nitrogen and carbon supply. The medium contained no inhibitors. Selectivity of the liquid medium was tested by inoculation of pure cultures of different bacteria belonging to the groups Bacillus, Pseudomonas, Enterobacteriaceae and Staphylococcus. It was found that the selectivity of the medium was complete for the examined range of bacteria. However, a similar result was obtained when nitrofurantoin broth was used. Applicability of the synthetic agar medium was also tested by a nation-wide inter-laboratory test using two milk samples containing 10(3)/ml (sample I) and 10(5)/ml (sample II) Pseudomonas aeruginosa. According to this test, no microbiologically relevant differences were found between the results obtained by Z-agar and cetrimide-agar a frequently used selective agar in case of sample II. However, a relevant and statistically significant difference was found in the results of sample I in favour of the Z-agar, that could indicate the presence of a low number of bacteria. Concerning repeatability and reproducibility, Z-agar proved to be superior to cetrimide agar.

Acetamides↗

PubMed1998

Comparison of the protein composition of Erysipelothrix rhusiopathiae strains of subtype 1A isolated from ducks and pigs.

Erysipelothrix rhusiopathiae strains isolated from duck carcasses and pigs were examined by sodium dodecyl sulphate--polyacrylamide gel electrophoresis (SDS-PAGE) and the results were evaluated by a computerised method in order to compare the strains for protein composition according to molecular mass. To characterise the similarity of the strains, Pearson's correlation coefficient was calculated. The degree of similarity between duck strains originating from the same flock was 980-991, while that of strains isolated from ducks and pigs varied between 836 and 991 on a scale of 0 to 1000. The method gives highly reproducible results and can be utilised in epidemiological investigations. Its use may provide new data on E. rhusiopathiae strains, complementing the results of methods recommended for this purpose earlier and increasing the efficiency of epidemiological investigations.

Animals↗

PubMed1998

Relationship of dietary fat and lysine level with body composition in broiler chickens.

The effect of dietary fat and/or lysine supplementation on the body composition of broiler chickens was studied. Body composition was measured by computed tomography (CT) and direct chemical analysis. Cockerel chicks from a previous experiment (Fekete et al., 1992) were used in this study. Ten chickens from each treatment group were euthanised, deep frozen and subjected to CT. Subsequently the bodies were dissected and ground to obtain homogeneous samples for chemical analysis. Supplementation of the diet with 6 g/kg lysine did not change total body composition but positively influenced the final body weight. In the treatment group receiving 40 g/kg added fat and 3 g/kg feed lysine (F-LYS-I) the higher body weight ran parallel with a higher fat content. The difference between the frozen body weight and final live body weight shows that lysine supplementation increased the water-holding capacity of muscle, which was the best in groups receiving a diet of normal energy content plus high lysine supplementation.

Animal Feed↗

PubMed1990

A synthetic, selective culture medium for Pseudomonas aeruginosa.

Selective and differentiating media consisting of simple chemical components have been developed, both in solid and in liquid form, for culturing Pseudomonas aeruginosa from foodstuffs. These media work on the basic principle that Gram-negative bacteria can utilize ammonia as inorganic nitrogen source. This principle has already been utilized for developing a culture medium for coliform bacteria (Szita and Biró, 1986; Szita et al., 1988). P. aeruginosa can produce the ammonia needed for its growth by decomposing acetamide. The liquid synthetic medium was compared with the nitrofurantoin broth and the solid one with cetrimide agar by parallel inoculation of 60 raw milk samples and 20 P. aeruginosa pure cultures. The main advantages of the synthetic media are their high selectivity, high sensitivity and rapidity. Owing to their advantageous properties, the new media can be recommended for replacing cetrimide agar and nitrofurantoin broth.

Acetamides↗

PubMed1986