Minimum Bactericidal Concentrations

Minimum bactericidal concentration The lowest concentration of antibiotic that will eliminate 3 logs or 99.9% of bacteria. 

The evaluation of patients treated for IE includes assessment of signs and symptoms, blood cultures, microbiologic tests (e.g., MIC, minimum bactericidal concentration [MBC], or serum bactericidal titers), serum drug concentrations, and other tests to evaluate organ function. 

Minimal Risk Level (MRL), 25 239 Minimum allowable continuous stable flow (MCSF) limits, for pumps, 21 83 Minimum bactericidal concentrations (MBCs), 18 262... 

In severe bacterial infections that are difficult to eradicate, such as endocarditis or osteomyehtis, it may be important to ensure that the patient s serum remains bactericidal at the lowest, or trough, concentration in the dosing interval. Dilutions of patient s serum can be incubated with the organism isolated from the patient and the minimum bactericidal concentration determined through serial dilutions. Treatment is considered adequate if the serum remains bactericidal at a dilution of 1 8. 

Table 9. Antimicrobial activity of compounds 11 and 49-53 Minimum Inhibitory Concentration, Minimum Bactericidal Concentration is reported in parentheses (fig/ml)...

Structure—Activity Relationships. Biological evaluation of penicillins yields information such as in vitro and in vivo antibacterial activities, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), protective effectiveness in laboratory animals (PD50), and pharmacokinetic characteristics including efficiency of absorption, serum levels, tissue distribution, urinary excretion, recycling, etc. Penicillins are also tested for ability to resist inactivation by (S-lactamase produced by both gram-positive and gram-negative bacteria,... 

In the laboratory, the relationship between an antimicrobial drug and a pathogen is described by the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). The MIC is the lowest drug concentration that inhibits bacterial growth. The MBC is the lowest drug concentration that kills 99.9% of the bacteria. 

Minimum bactericidal concentration (MBC) testing is required for the evaluation of novel antimicrobials. The MBC is the lowest concentration (in mg/L) of antimicrobial that results in >99.9% killing of the bacterium under test. The 99.9% cutoff is an arbitrary in vitro value with 95% confidence limits that has uncertain clinical relevance. 

FDA Food and Drug Administration GI gastrointestinal Hib H. influenzae type b HIV human immunodeficiency virus ICP intracranial pressure IL-1 interleukin 1 INF interferon LPS lipopolysaccharide MBC minimum bactericidal concentration MIC minimum inhibitory concentration NCCLS National Committee for Clinical Laboratory Standards... 

The PD of antimicrobial dmgs against microorganisms comprises three main aspects spectmm of activity, bactericidal and bacteriostatic activity, and the type of killing action (i.e., concentration-dependent, time-dependent, or co-dependent). Each of these is discussed below. Also described are the PD indices—minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC)—and the mechanisms of action of antimicrobial drugs. 

Minimum Inhibitory Concentration and Minimum Bactericidal Concentration... 

The broth dilution method is a simple procedure for testing a small number of isolates, even a single isolate. It has the added advantage that the same tubes can also be used for minimum bactericidal concentration(s) (MBC) tests. 

Antibacterial activity testing. Determined using the broth microdilution method. Incubations were performed for 18 h using an Ominolog automated incubator (Biolog Inc. 21,124 Cabot Boulevard, Hayward, CA 94545, USA). After this period MIC were checked by eye-ball observation and all weUs plated to determine the minimum bactericidal concentration (MBC). 

The antibacterial activity of the essential oil of Lippia multiflora was rst examined in vitro for antimicrobial activity against American type culture collection (ATCC) strains and clinical isolates of the buccal ora. A signi cant activity was found, with an minimum bactericidal concentration (MBC) of 1/1400 for streptococci and staphylococci, 1/800 for enterobacteria and neisseria, and 1/600 for Candida. A mouthwash was prepared with the essential oil at a 1/500 dilution, and this was used in two clinical trials. 

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