Antimicrobial performance

Superior antimicrobial activity in alkaline pH (seawater is always above pH 8), in the presence of nitrogenous organic matter, and due to lower volatility has been documented for bromine antimicrobials3 4. The pKa acid dissociation constants for HOC1 and HOBr are 7.4 and 8.7, respectively the dissociated acids are less effective antimicrobials4,5. Undissociated hypohalous acids are more effective because they are far better halogenating agents compared to the dissociated anion (hypohalite). Table 1 shows the effect of acid dissociation on antimicrobial performance in well-controlled laboratory experiments. 

Table 1. The effect of acid dissociation on antimicrobial performance against...

In the CIT/MIT blend the chlorinated species has by far the greater biocidal efficacy but is also the less stable of the two components. Although MIT alone has relatively low antimicrobial performance it has recently been discovered that this compound has truly synergistic activity when combined with BIT and such a blend has several advantages over CIT/MIT products. 

Study of the antimicrobial performance of silver-containing nanofibrous webs necessitates their contact with water. The water-swelling performance of nanofibrous... 

In recent years, silver has been gaining importance as an effective antimicrobial gent that does not result in bacteria resistance. Silver containing antimicrobial products have been developed so that a low concentration of silver ions can be released over time. A number of labaratoiy studies have shown the excellent antimicrobial performances of the silver containing antimicrobial products ... 

Staszewski, M., Pilosof, A.M.R., and Jagus, R.J. 2011. Antioxidant and antimicrobial performance of different Argentinean green tea varieties as affected by whey proteins Food Chemistry. 125 186-192. 

There are many ways textiles can be contaminated, due to their uses and/or through their environment. Potential threats include germs and fungi. However, there are a number of antimicrobial and antifungal medical textiles available nowadays. Antimicrobial performance testing using appropriate standard methods, test results, validation, and documentation is important. These tests are described in the foUowing section. 

The antimicrobial activ component of Sanitized MB PA 99-57 is ceramic based silver. The product is incorporated into the fiber made of polyamide PA 6 during the melt spinning process. The resulting fabric was tested according to the Japanese test method JIS L 1902 1998 (E) in the treated and unwashed state and after 5, 10 and 20 washings according to ISO 105/C01 at 40°C. The detailed results are given in table 7 and show the excellent antimicrobial performance. 

It is interesting to observe that the antimicrobial performance is seen to be even better after washing than before. This can be explained by the effect that the spin finishing oil used in the fiber spinning process reduces the availability of the... 

Product Chemically COSAN PMO-30 is a 30% solution of phenyl-mercuric oleate, which has the longest history of successful antimicrobial performance in the coatings industry. 

Chemical suppHers include basic manufacturers of active ingredients, formulators, and distribution or service industries. The relative importance of each depends greatly upon the industry being suppHed. In many instances, the vendor may supply a number of performance chemicals (eg, corrosion control agents or stabilizers) in addition to the antimicrobial agent. 

Microbiologists have developed the following hierarchy to categorize the expected level of performance of antimicrobial treatments ... 

Liquid Dosage Forms. Simple aqueous solutions, symps, elixirs, and tinctures are prepared by dissolution of solutes in the appropriate solvent systems. Adjunct formulation ingredients include certified dyes, flavors, sweeteners, and antimicrobial preservatives. These solutions are filtered under pressure, often using selected filtering aid materials. The products are stored in large tanks, ready for filling into containers. QuaUty control analysis is then performed. 

Relatively high levels of copper in pig diets can improve nutritional performance due to the antimicrobial effects in the gastrointestinal tract. However, if land is fertilized with dung from pigs and subsequently grazed by sheep, the sheep may suffer copper toxicity because of their increased susceptibility to copper compared with pigs. Similarly, pig diets would be unacceptable for sheep because of the high levels of copper therein. 

The sulfosuccinate monoester based on undecylenic acid monoethanolamide and its antimicrobial properties was described shortly before [12]. In comparison of shampoos containing different antidandruff agents, this sulfosuccinate s performance was favorably evaluated [13]. It was neutral with respect to lipid replacement on scalp and forehead after application of the respective shampoo. This undecylenic acid-based sulfosuccinate was also found to reduce dandruff formation in another investigation [14]. 

Salicylic acid peelings performed at 3- to 4-week intervals are a good choice for patients with rosacea. Salicylic acid peeling has antimicrobial activity, reduces erythrosis and prevents relapses. 

The intended application of an antimicrobial agent, whether for preservation, antisepsis or disinfection, will influence its selection and also affect its performance. For example, in medicinal preparations the ingredients in the formulation may antagonize preservative activity. The risk to the patient will depend on whether the antimicrobial is in close contact with a break in the skin or mucous membranes or is introduced into a sterile area of the body. 

Preexisting antimicrobial resistance is an increasing cause of treatment failure and is estimated to account for up to 70% of all treatment failures. Geography is the most important factor in HP resistance. Metronidazole-resistant strains are more prevalent in Asia (85%) than North America (30%).15 Primary resistance to amoxicillin and tetracycline remains low in both the United States and Europe. Clarithromycin resistance rates are estimated to be approximately 10% in the United States. Another confounding factor when evaluating potential antibiotic resistance is that culture and sensitivity studies are not routinely performed with HP infection. 

Reculture of specimens is not performed routinely except in few cases (e.g., endocarditis) or where a secondary infection is suspected because data may be misleading and lead to the addition of broader or more powerful antimicrobials... 

Ideally, lumbar puncture to obtain cerebrospinal fluid (CSF) for direct examination and laboratory analysis, as well as blood cultures and other relevant cultures, should be obtained before initiation of antimicrobial therapy. However, initiation of antimicrobial therapy should not be delayed if a pretreatment lumbar puncture cannot be performed. 

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