Minimum inhibition concentration

TABLE 4. Minimum inhibition concentrations (MIC, mmoll 1) of diorganotin chlorides and carboxylates82... 

Minimum inhibition concentration frog sciatic nerve... 

A water soluble quaternary ammonium derivative of chitosan (N-(2-hydroxy)propy 1-3 -trimethylammonium chitosan chloride, HTCC) was used as an antimicrobial agent for cotton fabrics. HTCC had a lower minimum inhibition concentration against Staphylococcus aureirs, Klebsiella pneumoiniae and Escherichia coU compared with that of chitosan, but the antimicrobial activity was lost on laundering. However, when cotton fabrics were treated simultaneously with HTCC and polycarboxylic acids (particularly butanetetracarboxylic acid) (BTCA),... 

Minimum inhibition concentration (ppm of the active ingredient in PVC film) against a number of bacteria Citrobacter freundii, Escherichia coli, Proteus vulgaris, Staphylococcus aureus, Salmonella choleraesuis. Enterococcus faecalis. Pseudomonas aeruginosa, Klebsiella pneumoniae) varied between (<200 and 400-600 ppm (<0.02-0.06%). It should be noted here that these bacteria are practically not relevant to WPCs, but rather to plasic-made biomedical devices. This example just shows a range of active antibacterial concentrations of the biocide. 

Fig. 22.4 Molecular properties can be divided into experimental (subdivided into biological and physicochemical) and in silico (subdivided into structural and substructural) properties, physicochemical and biological properties. Examples of experimental data are IC50 (binding affinity), MIC (antibacterial minimum inhibition concentration), LD50 (lethal dose), Vd (volume of distribution), F% (bioavailability), pKg (ionization constant), log P (partition coefficient from shake flask determination), log kn,(lipophilicity from HPLC measurement), A (hydrogen bond capability), solubility. Examples of calculated properties, either for whole molecule or for substituents or buildings blocks, are MW (molecular weight), MR (molar refractivity), molecular volume, PSA (polar surface area), HA (number of H-bond acceptors), HD (number of H-bond donors), CLOGP (calculated log P values), L (substituent length), B5 (substituent width), cr (Hammett constant), F, R (field and resonance parameters), TT (Hansch constant), f (hydrophobic fragmental constant).

To determine what microorganism types are susceptible to the antimicrobial soap product, as well as the rates of microbial inactivation, in vitro tests should be conducted. These include time-kill kinetic evaluations, minimum inhibition concentration evaluations, and microbial sensitivity tests. However, in order to determine the actual effectiveness, human-use studies must be conducted. There are three common ways of evaluating antimicrobial hand soaps (1) the health care personnel handwash evaluation, (2) the modified Cade handwash procedure, and (3) the general-use handwash evaluation. 

The agar plate method was used to determine the minimum inhibition concentration (MIC) of CM, Q, and CMQ as follows the samples were prepared at a concentration of 1% (w/v) and then autoclaved at 121°C for 25 min. Duplicate twofold serial dilutions of each sample were added to nutrient broth (beef extract 5 g, peptone 10 g to 1000 mL distilled water, pH 7.0) for final concentration of 0.1%, 0.05%, 0.025%, 0.0125%, 0.00625%, and 0.00313%. Some samples were prepared and diluted by the same way except for a final concentration of 0.00065% and 0.00033%. The culture of each bacterium was diluted by sterile distilled water to 105-106 CPU mL. A loop of each suspension was inoculated on nutrient medium with sample or control added. After inoculation, the plates were incubated at 37°C for 72 h, the colonies were counted, and the MIC values were obtained. The MIC was considered to be the lowest concentration that completely inhibited against on agar plates comparing, disregarding a single colony or a faint haze caused by the inoculum (Speciale et al. 2002). 

The minimum inhibition concentrations in Table 1 also show that, by virtue of intrinsic resistance, Escherichia coli, is less sensitive than the gram-positive bacterium Staphylococcus aureus, but more sensitive than Pseudomonades. The phenomenal resistance of Pseudomanas aeruginosa to quaternary ammonium salts (III. 16) enables this non-sporing bacterimn to survive in solutions of QACs. This intrinsic QAC resistance is attributed to the special composition of the... 

Table 1. Sensitivities of Gram-negative and Gram-positive Bacteria to Phenol Derivatives Arranged in a Succession of Increasing Degrees of Hydrophobicity — Minimum Inhibition Concentrations (mg/litre) in Nutrient Agar...

Table 2. Minimum Inhibition Concentrations (MIC) of Ethanol in Nutrient Agar...

Because of its effectiveness against slime forming microbes (minimum inhibition concentration approx. 2-5 mg/litre) glutaraldehyde may be used in paper mills as a slimicide which does not cause any waste water problems. Especially since paper mills increase the pH in their process water to 7 or even to the slightly alkaline state, they profit from the higher activity of glutaraldehyde in such media. 

Substance classes Properties — Effectiveness — Applications Minimum inhibition concentrations for ... 

The action of -butanolhemiformal corresponds to its formaldehyde content. Minimum inhibition concentrations ... 

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