Antimicrobial Actions

Antimetastatic activity Antimicrobial action Antimicrobial activity... 

Sodium and potassium benzoate are employed in a wide range of preservative appHcations because they provide an effective combination of antimicrobial action, low cost, and safety. Although sodium and potassium benzoate are the preservatives offered in the marketplace, the actual active ingredient being sold is free (or undissociated) benzoic acid. The benzoate ion has essentially no antimicrobial properties. Since it is the undissociated (free) benzoic acid that provides the antimicrobial action, sodium benzoate and potassium benzoate are recommended for use in appHcation areas where the pH is at 4.5 or lower (Table 8). 

Sodium benzoate is also finding increasing appHcation as a corrosion inhibitor. It is incorporated into paper wrapping materials for the prevention of mst or corrosion in the production of such diverse items as razor blades, engine parts, bearings, etc. It is also used in the automotive industry as a corrosion inhibitor in engine cooling systems (at 1.5%), mainly in Europe and Japan. Unlike in its appHcation as a preservative where free benzoic acid is required to provide antimicrobial action, it appears to be the benzoate ion that provides the corrosion protection. 

The dissociation of hypochlorous acid depends on the pH. The unionized acid is present in greater quantities in acid solution, although in strongly acid solution the reaction with water is reversed and chlorine is Hberated. In alkaline solutions the hypochlorite ion OCL is increasingly Hberated as the pH is increased. The pH is important because unionized hypochlorous acid is largely responsible for the antimicrobial action of chlorine in water. Chlorine compounds are therefore more active in the acid or neutral range. The hypochlorites most commonly employed are sodium hypochlorite [7681-52-9] or calcium hypochlorite [7778-54-3]. 

Another compound, the antimicrobial action of which is associated with chelation, is 2-pyridinethiol-A/-oxide [3811-73-2] (Omadine). Activity has been shown to depend on coordinating property. The iron chelate is active, but not the free pyridine compound (200). In the form of its zinc chelate it is found in shampoos to control seborrheic dermatitis (201). Other appHcations of this useful chemical include preservation of adhesives, plastics, latex paints, polyurethane foam, and metal working fluids (202). 

Antimicrobial action peculiarities and pharmacokinetics of novel fluoroquinolones 98MI6. 

Because it only converts to benzoic acid in acidic environments, it is not used for its antimicrobial action unless the pH is 3.6 or below. In the food industry, it is used in items such as jams, salad dressing, juices, pickles, and carbonated drinks. 

The antimicrobial action of ethambutol, like that of isoniazid, is specific for mycobacteria, suggesting a target in the unique components of the mycobacterial cell wall. Cells treated with ethambutol accumulate an isoprenoid intermediate, decaprenyl-arabinose which is the source ofarabinose in the arabinogalactan polymer. This suggests that ethambutol blocks assembly of the arabinogalactan through inhibition of an arabinosyl transferase enzyme. 

Franklin J.J. Snow G.A. (19 9) Biochemistry of Antimicrobial Action, 4th edn. London Chapman Hall. 

The efficacy of an antimicrobial agent must be investigated by appropriate capacity, challenge and in-use tests to ensure that a standard is obtained which is appropriate to the intended use (Chapter 11). In practice, it is not usually possible to know which organisms are present on the articles being treated. Thus, it is necessary to categorize chemicals according to their antimicrobial capabilities and for the user to have an awareness of what level of antimicrobial action is required in a particular situation (Table 10.1). 

McComb, D. Ericson, D. (1987). Antimicrobial action of new, proprietary lining cements. Journal of Dental Research, 66, 1025-8. 

Different organic acids, primarily lactic acid, have been successfully used for decontamination of whole livestock carcasses, and the application of different organic acids used for decontamination has also been tested in the fruit and vegetable industry. Organic acids other than lactic acid that are known to have bactericidal effects are acetic, benzoic, citric, malic, propanoic, sorbic, succinic and tartaric acids (Betts and Everis 2005). The antimicrobial action is due to a reduction in the pH in the bacterial environment, disruption of membrane transport, anion accumulation or a reduction in the internal pH in the cell (Busta et al., 2001). Many fruits contain naturally occurring organic acids. Nevertheless, some strains, for example E. coli 0157, are adapted to an acidic environment. Its survival, in combination with its low infective dose, makes it a health hazard for humans. 

In terms of the spectrum of antimicrobial action, oxacillin is analogous to benzylpenicillin. However, it combines the resistance to penicillinase with durability in an acidic medium, which allows it to be used not only intramuscularly, but also orally. It is used for infections caused by... 

Despite the few differences in these dmgs in terms of pharmacokinetic features, then-broad spectrum of antimicrobial action is similar in many regards. 

Kanamycin A is similar to streptomycin and neomycines and has a broad spectrum of antimicrobial action. It is active with respect to most Gram-positive as well as Gram-negative microorganisms (staphylococci, gastric bacilli, rabbit fever, Fridlender s bacillus, proteus, shigella, salmonella). 

Pyrimethamine, a folic acid antagonist, exhibits antimicrobial action against the causative agent of malaria and possesses sporontocidal action. It is also effective with respect to the causative agent of toxoplasmosis. It is used for preventing malaria and treating toxoplasmosis. 

For damaged skin, mild, nonantimicrobial skin-cleansing products may be used to remove dirt and debris. If antimicrobial action is needed (e.g.,... 

Solvolysis of the thiadiazine 184 leads to gradual elimination of a variety of small aliphatic molecules. They have been observed to recombine partly to four-membered N,N- and N,S-containing heterocycles via secondary condensation reactions (Eq. 40). It is proposed that the antimicrobial action of thiadiazines can in part be correlated to their hydrolysis products. 

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