The chromogenic cephalosporin beta-lactamase test is a qualitative procedure for detecting the production of beta-lactamase by bacteria. The reaction is based on the production of a colored compound when the substrate, nitrocefin, is exposed to a ß-lactamase-producing culture. The enzyme, beta-lactamase, originally described by Abraham and Chain, is produced by various organisms and is a mechanism of their resistance to penicillins and cephalosporins. Test methods used to detect ß-lactamase include iodometric, acidimetric and chromogenic cephalosporin procedures..Some staphylococci may require induction (exposure to a ß-lactam agent) to increase production of beta-lactamase to detectable levels. According to standard references, any negative ß-lactamase test result from a non-induced stapylococcal isolate, despite the test method, should be confirmed by induction of the isolate and repeat testing. BBL BD DrySlide Nitrocefin employs nitrocefin, a cephalosporin compound first described by Glaxo Research (Middlesex, England), in the chromogenic cephalosporin test methodology. BBL BD DrySlide Nitrocefin discounts available for Government, Universities and resale orders.
