title: Presumptive identification of group D streptococci: the bile-esculin test.
abstract: Six tests commonly used for the presumptive identification of group D streptococci were evaluated. Strains tested included 282 group D streptococci and 366 non-group D. Ratios of percentages of group D to non-group D strains which gave positive reactions for each test are as follows: bile-esculin, 100:2; salt tolerance, 88:24; heat tolerance, 100:80; SF broth, 86:1; KF broth, 99:40; and methylene blue milk reduction, 90:17. These data indicate that the bile-esculin test provided a reliable means of identifying group D streptococci and differentiating them from non-group D streptococci. Methodology for reading and interpreting positive reactions and time of incubation of the bile-esculin medium was defined. Evidence of the need for standardization of salt and heat-tolerance tests was obtained.
mesh_terms: D000362:Agar; D000818:Animals; D001431:Bacteriological Techniques; D001647:Bile Acids and Salts; D003470:Culture Media; D004352:Drug Resistance, Microbial; D005419:Flavonoids; D006461:Hemolysis; D006358:Hot Temperature; D008722:Methods; D008751:Methylene Blue / Q000378:metabolism; D008892:Milk; D012703:Serotyping; D012965:Sodium Chloride / Q000494:pharmacology; D013291:Streptococcus / Q000145:classification / Q000187:drug effects / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D001647:Bile Acids and Salts; D003470:Culture Media; D005419:Flavonoids; D012965:Sodium Chloride; D000362:Agar; D008751:Methylene Blue