Enumeration of sublethally heated staphylococci in some dried foods.
The effect of 45 substances to restore the salt tolerance of sublethally heat-injured Staphylococcus aureus was tested. Sodium pyruvate, yeast extract, L-histine, casitone (Difco), adenosine triphosphate, and acetylphosphate were effective. For enumeration a repair medium was first used, containing sodium pyruvate and penicillin in 1% skim milk. This step was followed by counting on Baird-Parker agar with penicillinase. This method was selective; fewer than 100 staphylococci/g food could be enumerated and it gave counts about 8 times higher than the method of Giolitti and Cantoni used as a five-tube most probable number technique. Heat injury sensitized S. aureus to polymyxin.
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001431:Bacteriological Techniques; D002452:Cell Count; D004352:Drug Resistance, Microbial; D005506:Food Contamination; D005516:Food Microbiology; D005958:Glucosephosphates / Q000494:pharmacology; D006639:Histidine / Q000494:pharmacology; D006358:Hot Temperature; D008892:Milk; D009943:Organophosphorus Compounds / Q000494:pharmacology; D010461:Peptones / Q000494:pharmacology; D011113:Polymyxins / Q000494:pharmacology; D011773:Pyruvates / Q000494:pharmacology; D012440:Saccharomyces; D012965:Sodium Chloride / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects / Q000302:isolation & purification*
D005958:Glucosephosphates; D009943:Organophosphorus Compounds; D010461:Peptones; D011113:Polymyxins; D011773:Pyruvates; D012965:Sodium Chloride; D006639:Histidine; D000255:Adenosine Triphosphate