Effect of beef broth protein on the thermal inactivation of staphylococcal enterotoxin B1

Abstract

Enterotoxin B produced by Staphylococcus aureus 243 in brain heart infusion broth was concentrated by dialysis against 40% polyethylene glycol (20 M), partially purified on a Sephadex G-100 column and heated at 1100C in thermal death time cans. Various heating menstrua included 0.04 M Veronal buffer (pH 7.4), beef broth, and fractions of beef broth obtained by ultrafiltration or precipitation with ammonium sulfate. The toxin was assayed serologically using the microslide gel double-diffusion method. The time required for 90% inactivation at 1100C (D110 value) obtained in buffer and in beef broth was 18 and 60 min, respectively. When the concentration of beef broth was increased fivefold, the

Staphylococcus aureus and related staphylococci in foods: ecology, proliferation, toxinogenesis, control and monitoring

“…Cardinal Fung 1976;Lee et al 1977; Stelma & Bergdoll 1982; Bergdoll 1989) make it impossible to give an accurate figure for the extent of their heat resistance. This is compounded by the effect of the composition of the food substrate on heat inactivation of enterotoxins.…”

Growth and Production of Enterotoxin A by Staphylococcus aureus on “Home‐style” French Fries

“…The toxin can remain serologically and biologically active after exposure to 121 °C for 19 to 30 min in buffer or beef bouillon (Denny et al, 1971, Humber et al, 1975, Tibana et al, 1987, Anderson, 1996. Denny et al (1971) and Lee et al (1977) demonstrated that using food as the heating medium was shown to increase the thermal stability of staphylococcal enterotoxin Ϸ 2-to 5-fold. They suggested that the food components provided some protective effect possibly through protein-protein interactions (Denny et al, 1971).…”

Comparison of Reverse Passive Latex Agglutination Test and Immunoblotting for Detection of Staphylococcal Enterotoxin a and B

“…SEs are resistant to inactivation by gastrointestinal proteases such as pepsin. Heat stability is one of the most important physical and chemical properties of SEs in terms of food safety (Denny et al 1971;Humber et al 1975;Lee et al 1977;Hoover et al 1983).…”