[HPLC study of the inhibition of enterobacterial cephalosporinases by cefmenoxime]

High performance liquid chromatography (HPLC) has shown that cefmenoxime and cefotaxime are stable to the cephalosporinase of Enterobacter cloacae P99 , Morganella morganii GN 1510 and Serratia liquefaciens 132. They are significantly resistant to hydrolysis by 100 cephalosporinase units (cephalosporinase production of 10(12) bacterial). Cefmenoxime and cefotaxime are also inhibitors of cephalosporinase at the concentration of 5.10-10 micrograms per 10-10 unit of enzyme.