Przezywalnosc enterotoksycznych Bacillus cereus w warunkach imitujacych srodowisko zoladka czlowieka

• Autorzy: Berthold A , Ramatowska J.

Warianty tytułu

EN

Survival of Bacillus cereus enterotoxic strains in medium simulating human stomach environment

• Języki publikacji: PL

Abstrakty

EN

The aim of this work was to determine the survival of spores and vegetative cells of enterotoxic strains of B. cereus in a medium (GM-milk) simulating human stomach environment after consumption of milk or dairy products. Gastric medium (GM-milk) was prepared by mixing equal volumes of a gastric electrolyte solution (4.8 g/l NaCl, 1.56 g/l NaHCO₃, 2.2 g/l KCl, 0.22 g/l CaCl₂, 500 U/l pepsin solution [Sigma-Aldrich Chemie GmbH, nr kat. P6887]) with UHT milk (0,5% fat content). The total count of B. cereus after 6-hours’ incubation in GM-milk (pH~2 and pH~4,5) was determined in a MYP [Merck nr kat. 1.05267.]. After incubating the spores or vegetative cells in a pH~4,5 medium, the count remained unchanged in 70% and 30% strains, decreased by about 1.0 log cfu/ml in 20% and 40% strains or decreased by about 2.0 log cfu/cm³ in 10% and 30% strains, respectively. After incubating the spores in a pH~2 medium, the count remained unchanged in 10% strains, decreased by about 1.0 log cfu/cm³ and 2.0 log cfu/cm3 in 40% and 50% of the strains, respectively. In the same medium no survival of any tested strains of vegetative cells in 1 ml was ascertained after 1 hour incubation. The study demonstrated that the survival of B. cereus depended on the pH of the medium simulating the stomach environment and the physiological state of the cells (spores or vegetative forms).

Słowa kluczowe

PL

szczepy enterotoksyczne; Bacillus cereus; przezywalnosc; zanieczyszczenia mikrobiologiczne; mleko; pozywka imitujaca srodowisko zoladka

• Wydawca: -
• Czasopismo: Medycyna Weterynaryjna
• Rocznik: 2008
• Tom: 64
• Numer: 01
• Opis fizyczny: s.101-104,rys.,tab.,bibliogr.

Twórcy

autor

Berthold A

• Szkola Glowna Gospodarstwa Wiejskiego, ul.Nowoursynowska 159 C, 02-787 Warszawa

autor

Ramatowska J.

Bibliografia

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