Detection of vitamin B12 derivatives in serum by thin-layer chromatography and bioautograph technique.

The authors report a modified T.L.C. - bioautograph method for detection of vitamin B12 active compounds in serum. This method offers particular advantages because it allows the identification and the quantitative assay of picograms of vitamin B12 active compounds.

Recurrence of Pelecypod-associated cholera in Sardinia.

From Oct. 30 to Nov. 7, 1979, 10 people in the Sardinian province of Cagliari had onset of bacteriologically confirmed cholera. Two symptom-free excretors of Vibrio cholerae O:1 were detected in household contacts of the patients. There were no deaths. All but 1 of the 12 people with V. cholerae O:1 infection gave a history of recent consumption of marine bivalves known locally as arselle (pelecypods). Triplicate matched neighbourhood controls for each of the first 7 cases identified were also interviewed; none had recently eaten arselle. V. cholerae O:1 was also recovered from samples of water and bivalves obtained from a lagoon on the outskirts of the city of Cagliari. Arselle had also been implicated as the vehicle of transmission in 1973 in the last outbreak of cholera in Sardinia. It seems unlikely that cholera transmission had persisted locally in the interim.

[Detection of heat-stable staphylococcal nucleases in foods of various kinds]. / Ricerca della termonucleasi stafilococciche in alimenti di varia natura.

Herewith are the results of a research on determination of staphylococcal heat-stable nuclease in food. From this research derives clearly the need to devote to the determination of heat-stable deoxyribonuclease as an useful indirect index, fit to give menful informations on the pollution of different kind of food by the side of patogen Staphylococci even on food products under processes of pasteurization or of sterilization.

[Study of piruvic acid pool as indirect index of microbial count in foods and beverages (author's transl)]. / Indagine sulla determinazione del "pool di acido piruvico" quale indice indiretto della carica microbica in alimenti e bevande

The quantities are given of pyruvate in a medium to remark any possible connection between varieties of pyruvate and present bacterial flora concentration. We found some connection between the two experiments, even though, not always are very easily to menage.

[Comparative studies on the course of microbial flora in natural mineral waters bottled in glass, PVC and laminated polyethylene]. / Osservazioni comparative sull'andamento della flora microbica delle acque minerali naturali confezionate in vetro, "PVC" e "tetrabrik"

The Authors report the results of comparative investigations carried out on some mineral waters bottled in various containers (laminated polyethylene, glass, PVC). The microbic charges vary in relation to the kind of container and resulted to be lower in the case of containers made of polyethylene.

[Improvement of an enrichment medium for Vibrio parahaemolyticus and Vibrio alginolyticus]. / Messa a punto di un terreno di arricchimento per il "Vibrio parahaemolyticus" ed il "Vibrio alginolyticus"

Enriched cultures ofsing a selective substratum treated with sulfisoxazolo. This substratum has a composition in aminoacids, vitamins of the B-group, glucides and sodium chloride similar to that of homogenized Mytilus edulis which had turned out to be an excellent natural medium for the growth of the aforecited halofilic vibrios.

[Determination of bacteria count by enumeration of microcolonies with an electronic counter apparatus (author's transl)]. / Determinazione della carica microbica mediante numerazione delle microcolonie eseguita al contatore elettronico di particelle

In this paper a method is described to determine the bacteria count of samples by enumerating the microcolonies with the aid of a "Coulter Counter" automatic apparatus. Samples of bacterial cultures were incubated in a suitable medium at 32 degrees C for 12 h, then passed through a Coulter Counter aperture of 200 mu diameter to count the microcolonies. Microcolonies from cultures grown in similar conditions were also enumerated by the classical plate method. Comparison showed a good correction between the two sets of results after logarithmic transformation. Some advantages and limitations of this automatic technique are discussed, in view of its routine employment in food analysis.