[Measure by turbidimetry and bactericidal effect of the speed of action of clavulanic acid, amoxicillin and their combinations on a Haemophilus influenzae producer of beta-lactamase].
The amoxicillin-acid clavulanic acid combination is known to be active on H. influenzae beta-lactamase producer. Clavulanic acid possesses its own antibacterial activity at high concentrations. As the combination of two beta-lactams is sometimes antagonist, we studied the action of amoxicillin, clavulanic acid alone and in combination on H. influenzae beta-lactamase producer by kinetic turbidimetry and time-kill curve. Clavulanic acid alone has slowed down the growth at 8 micrograms/ml, has inhibited at 32 micrograms/ml and was bactericidal at 128 micrograms/ml. The amoxicillin-clavulanic acid combination (proportion 4/1) was bactericidal at 2-0.5 micrograms/ml. The speed of bactericidal activity was only slightly dependent on concentrations. The increase in biomass measured by turbidimetry has been important. As for all beta-lactams it was due to the formation of spheroplasts, non viable after 24 h.
Yourassowsky
E
E
Van der Linden
M P
MP
Lismont
M J
MJ
Crokaert
F
F
Glupczynski
Y
Y
D000658:Amoxicillin / Q000494:pharmacology*; D002969:Clavulanic Acids / Q000494:pharmacology*; D004359:Drug Therapy, Combination; D006193:Haemophilus influenzae / Q000187:drug effects* / Q000201:enzymology; D009391:Nephelometry and Turbidimetry; D001618:beta-Lactamases / Q000378:metabolism*
D002969:Clavulanic Acids; D000658:Amoxicillin; D001618:beta-Lactamases
Mesure par turbidométrie et bactéricidie de la vitesse d'action de l'acide clavulanique, de l'amoxicilline et de leurs associations sur Haemophilus influenzae producteur de bêtalactamase.