Bacteria Antimicrobial

Bacteria, antimicrobials against, 12, 456 Baeyer-Villiger oxidation, via tin amides, 9, 370 Barbier-Grignard-type reactions, and sonochemical metal insertions, 1, 315 Barbier-type reactions allenyl and propargyl tins, 9, 358 with allylic tins, 9, 357 with antimony(III) compounds, 9, 426 with bismuth(III) compounds, 9, 433 with cerium reagents, 10, 409 with indium compounds, 9, 685... 

Piddock L J1994 New quinolones and Gram-positive bacteria. Antimicrobial Agents Chemotherapy 38 163-169... 

Costerton J, EUis B, Lam K, Johnson F, Khoury A. (1994). Mechanism of electrical enhancement of efficacy of antibiotics in killing biofihn bacteria. Antimicrobial Agents and Chemotherapy 38 2803-2809. 

Preservatives keep food fresh by slowing the growth of mold and bacteria (antimicrobial preservatives), preventing oxidation (antioxidants), or slowing enzymes from continuing the ripening process after a fruit or vegetable was picked or cut. 

Reis, J., Paula, A., Casarotti, S., and Penna, A. (2012) Lactic acid bacteria antimicrobial compounds characteristics and apphcations. Food Eng. Rev., 4, 124-140. 

Therefore, besides strict hygienic rules during insertion of the device, the development of new materials able to counteract microbial adhesiveness and colonization has become a critical issue in recent years. The two principal approaches to prevent microbial adhesiveness are (1) the development of polymers with antifouling properties, and (2) the development of polymers with antimicrobial properties. Such materials either repel microbes (antifouhng) or kill bacteria (antimicrobial) present in the surface proximity. 

Alkaliphilic bacteria Antimicrobial compound produced Inhibitory activity against Reference... 

Other Properties. Polyester fibers have good resistance to uv radiation although prolonged exposure weakens the fibers (47,51). PET is not affected by iasects or microorganisms and can be designed to kill bacteria by the iacorporation of antimicrobial agents (19). The oleophilic surface of PET fibers attracts and holds oils. Other PET fiber properties can be found ia the Hterature (47,49). 

Preservatives. Without control of yeasts (qv), molds, and bacteria, the food industry would experience considerable economic losses each year owing to spoilage. Sugar, salt, and wood smoke have been used for centuries to preserve food. These methods, however, are not compatible with all food products thus preservatives, also known as antimicrobials, are used. 

Resistance to antimicrobial agents is of concern as it is well known that bacterial resistance to antibiotics can develop. Many bacteria already derive some nonspecific resistance to biocides through morphological features such as thek cell wall. Bacterial populations present as part of a biofilm have achieved additional resistance owkig to the more complex and thicker nature of the biofilm. A system contaminated with a biofilm population can requke several orders of magnitude more chlorine to achieve control than unassociated bacteria of the same species. A second type of resistance is attributed to chemical deactivation of the biocide. This deactivation resistance to the strong oxidising biocides probably will not occur (27). 

Other Nitrogen Compounds. The basis of the sophisticated nitrogen compounds Hsted in Table 10 is the reaction of formaldehyde with amino compounds. A significant amount of Hterature details investigation of the mechanism of action, particularly whether or not the antimicrobial activity depends on decomposition to formaldehyde (40—42). These compounds tend to have substantial water solubiUty and are more effective against bacteria than fungi and yeasts. Key markets for these compounds are metalworking fluids, cosmetics, and in-can preservation of paints (see Alkanolamines Amines, fatty amines). 

Other appHcations of firefly hioluminescence include measurement of the activity of bacteria in secondary sewage treatment activated sludge (296,297), detection of bacteria in clean rooms and operating rooms, measurement of bacteria in bottled foods, beverages (298), and pharmaceuticals (299), determination of the antimicrobial activity of potential dmgs (300), determination of the viabiHty of seeds (301), and measuring marine biomass concentrations as a function of ocean depth or geographical location (302). 

Antibiotic and Antimicrobial Drugs. The antimicrobial agents (119) flumequiae (160) and (161), and methylflumequiae (S-25930) (162) and (163) effectively eliminate a number of microbial pathogens via inhibition of the topoisomerase II enzyme of c-DNA containing bacteria (120) (see... 

Cooling water pH affects oxidizing antimicrobial efficacy. The pH determines the relative proportions of hypochlorous acid and hypochlorite ion or, in systems treated with bromine donors, hypobromous acid and hypobromite ion. The acid forms of the halogens are usually more effective antimicrobials than the dissociated forms. Under some conditions, hypochlorous acid is 80 times more effective in controlling bacteria than the hypochlorite ion. Hypochlorous acid predominates below a pH of 7.6. Hypobromous acid predominates below pH 8.7, making bromine donors more effective than chlorine donors in alkaline cooling waters, especially where contact time is limited. 

Ghlorhexidine Gluconate. Chlorhexidine gluconate [18472-51 -0] (l,l -hexamethylene bis[5-(p-chlorophenyl) biguanide] di-D-gluconate) is used as an antimicrobial against both aerobic and anaerobic bacteria ia the oral cavity. It is used as a therapeutic supplement ia the treatment of gingivitis, periodontal disease, and dental caries. A mouth riase form is available as a 0.12 wt% aqueous solution (288). 

Povidone—iodine is a brown, water-soluble powder containing approximately 10% iodine. However, the amount of free iodine, which is responsible for the antimicrobial activity, is low in a concentrated solution, but is released as the solution is diluted (41). Concentrated solutions have actually been contaminated with bacteria (42). For use as an antiseptic, povidine—iodine is diluted with water or alcohol to a concentration of 1% iodine. Detergents are added if it is used as a surgical scmb. lodophors are important as broad-spectmm antiseptics for the skin, although they do not have the persistent action of some other antiseptics. They are also used as disinfectants for clinical thermometers that have been used by tuberculous patients, for surface disinfection of tables, etc, and for clean equipment in hospitals, food plants, and dairies, much as chlorine disinfectants are used. 

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