头孢哌酮舒巴坦复方制剂的抗菌活性及其对细菌β-内酰胺酶的稳定性研究

Studies on stability of cefoperozone to bacterial β-Iactamase and inhibitory action of sulbactam on β-Iactamases

目的观察头孢哌酮 (CPZ)和舒巴坦 (SBT)复方制剂 (1∶1)的体外抗菌活性及其对细菌 β 内酰胺酶的稳定性 ,并检测SBT对 β 内酰胺酶的抑制作用。方法用琼脂二倍稀释法测定药物的最低抑菌浓度 (MIC) ,以头孢噻吩为酶解底物 ,用紫外分光光度计测定酶对各种抗生素的水解率。结果SBT显著降低CPZ的MIC ,所试细菌的 β 内酰胺酶对头孢噻吩和头孢哌酮的平均水解率分别为 75 .1%和 4 9.1% ,加用等浓度SBT后 ,酶对头孢哌酮的平均水解率降至 8.2 % (P <0 .0 5 )。结论SBT增强CPZ抗菌作用可能与抑酶作用有关。

Objective To detect the β-lactamase-inhibiting activities of sulbactam(SBT) and the stability of cefoperozonc(CPZ)/sulbactam(1∶1) preparation to bacterial 13-lactamases. Methods The inhibitory action of SBT on β-laetamases fromstandard β-lactamase- producing strains and clinical isolated ones were determined by ultraviolet spectrophotometer. Results When the concentration of the antibiotics was 0. lmmol/L, the average hydrolysis rates(HR) of CPT and CPZ by eightβ-lactamases were 75.1% and 49.1%, respectively. After adding the same concentration of SBT, the HR dropped to 8. 2 % (P<0.01). Conclusion The synergism of CPZ and SBT against bacteria may be due to β-lactamase-inhibiting activities ofSBT.