OTHER ANTIMICROBIAL AGENTS

Lysozyme is a bacteriolytic enzyme isolated initially by Alexander Fleming in 1922 from human mucousal secretions. It has since been reported from bovine and human milk, and the msgor commercial source, egg white. Lysozyme has been used in the pharmaceutical industry since 1954 and, additionally, is currently used in cheese. Recent work has suggested its applicability in prevention and/or management of MLF. It is presently in the process of registration for winemaking (Villa, 1996). 

Lysozyme brings about hydrolysis of the bacterial cell wall, specifically, the P-1, 4-glycosidic bonds. Activity toward gram-negative species is limited because of the protective outer cell membrane in this group (Villa, 1996). Lysozyme has no effect on yeasts. 

Lysozyme s application is directed primarily toward white wines for the control of LAB. Unlike compounds previously discussed, lysozyme exhibits activity toward all species and strains of LAB studied. At its suggested use level of 250-500 mg/L, the enzyme preparation may be added before alcoholic fermentation to prevent MLF, at some time during MLF, or upon completion to prevent subsequent activity of unwanted LAB. Its activity is not affected by ethanol, although upon reaction with tannin and pigment complexes, activity decreases (Villa, 1996). Similarly, bentonite dramatically decreases activity. In white juice, this ranged from 37% reduction after bentonite additions of 0.25 g/L to complete inactivation with additions of 1 g/L. In white wines, the impact of bentonite was less, ranging from 10% reduction with 0.25 g/L to 75% reduction at 1.0 g/L. The effect of sulfur dioxide additions in white wine was also investigated. In this case. Villa reports that SO2 at 80 mg/L had an indirect effect on lysozyme activity 

As noted previously, lysozyme complexes with and is partially inactivated by red wine phenolics and bentonite. In red wines, utilization may have an indirect sensory impact on palate structure similar to that of proteinaceous fining agents. In white wines, potential protein instability may result from its utilization. Thus, treated wines should be evaluated and treated with bentonite as appropriate. As of this writing, lysozyme is in the process of approval for winemaking purposes. 

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Other antimicrobial agents Triclosan MnP from P. chrysosporium LAC from T. versicolor Flask scale Flask scale... 

Penicillin antibiotics must be used with caution because some strains of Bacillus anthracis possess an enzyme that inactivates penicillin. Other antimicrobial agents can be used as alternatives if the listed drugs are unavailable or in short supply. These include erythromycin, imipenem, clindamycin, vancomycin, and chloramphenicol.3... 

Mastitis is nearly always caused by bacterial infection. The introduction of benzyl penicillin for the treatment of intramammary infections (IMI) caused by Gram positive bacteria, followed by products containing other antimicrobial agents, was a major advance in... 

Superinfection As with other antimicrobial agents, superinfections caused by resistant organisms (eg. Pseudomonas or Candida species) can occur. 

May be effective in the treatment of acute urinary tract infections caused by susceptible strains of gram-positive and gram-negative bacteria, especially Enterobacter sp. and Escherichia coii. It usually is less effective than other antimicrobial agents in the treatment of urinary tract infections caused by bacteria other than mycobacteria. Consider using only when the more conventional therapy has failed and when the organism has demonstrated sensitivity. 

Other antimicrobial agents used in urinary tract infection e.g. sulfonamides, quinolones, penicillins, ... 

Certain antimicrobial agents used to treat urinary tract infections act better in acidic pH i.e. nitrofurantoin, tetracycline, methenamine, cloxacillin. Certain other antimicrobial agents such as gentamicin, cephalosporins, fluoroquinolones, cotri-... 

Nitrofurantoin is bacteriostatic and bactericidal for many gram-positive and gram-negative bacteria but P aeruginosa and many strains of proteus are resistant. There is no cross-resistance between nitrofurantoin and other antimicrobial agents and resistance emerges slowly. As Escherichia coli resistant to trimethoprim-sulfamethoxazole and fluoroquinolones has become more common, nitrofurantoin has become an important alternative oral agent for treatment of uncomplicated urinary tract infection. 

Rutala (1996) prepared a comprehensive set of guidelines for sporicidal agents to combat bacterial spores and in 1996 provided guidelines for the selection of topical and other antimicrobial agents. 

Fosfomycin trometamol, a stable salt of fosfomycin (phosphonomycin), inhibits a very early stage of bacterial cell wall synthesis (Figure 43-5). An analog of phosphoenolpyruvate, it is structurally unrelated to any other antimicrobial agent. It inhibits the cytoplasmic enzyme enolpyruvate transferase by covalently binding to the cysteine residue of the active site and blocking the addition of phosphoenolpyruvate to UDP-V-acetylglucosamine. This reaction is the first step in the... 

In vitro activity of Bay O 9867, a new quinoline derivative, compared with those of other antimicrobial agents. Antimicrob. Agents Chemother., 1983, 23, 559-564. 

Garcia-Rodriguez JA, et al. In vitro activity of BAY y 3118, and nine other antimicrobial agents against anaerobic bacteria./. Chemother., 1995, 7, 189-196. 

Aldridge KE. Increased activity of a new chlorofluoroquinolone, BAYy3118, compared with activities of ciprofloxacin, sparfloxacin, and other antimicrobial agents against anaerobic bacteria. Antimicrob. Agents Chemother., 1994, 38, 1671-1674. 

Esposito S, Noviello S, Ianniello F. Activity of moxifloxacin and twelve other antimicrobial agents against 216 clinical isolates of Streptococcus pneumoniae. Chemotherapy, 2001, 47, 90-96. 

Berron S, Vazquez JA, Gimenez MJ, de la Fuente L, Aguilar L. In vitro susceptibihties of 400 Spanish isolates of Neisseria gonorrhoeae to gemifloxacin and 11 other antimicrobial agents. Antimicrob Agents Chemother 2000 44(9) 2543-4. 

Cohen LS, Wechsler AS, Mitchell JH,GlickG, Depression of cardiac function by streptomycin and other antimicrobial agents. Am J Cardiol, 1970,26 505-11. 

It may be used either alone or in combination with other paraben esters or with other antimicrobial agents. In cosmetics, it is the fourth most frequently used preservative. ... 

The parabens are effective over a wide pH range and have a broad spectrum of antimicrobial activity, although they are most effective against yeasts and molds. Antimicrobial activity increases as the chain length of the alkyl moiety is increased, but aqueous solubility decreases therefore a mixture of parabens is frequently used to provide effective preservation. Preservative efficacy is also improved by the addition of propylene glycol (2-5%), or by using parabens in combination with other antimicrobial agents such as imidurea see Section 10. 

Other antimicrobial agents that have been used intraarticularly include methicillin, ticardlUn-clavulanic acid, ceftiofur and imipenem. Ceftiofur has been shown to develop high synovial fluid concentrations following intraarticular... 

Other antimicrobial agents that have been incorporated into PMMA beads and shown to have useful elution profiles include penicillin G (ben-zylpenicillin), ampicillin, amoxicillin, flucloxacillin, amoxiciUin-clavulanate, cefamandole, cefazolin, tobramycin, netilmicin, imipenem, erythromycin, ciprofloxacin, trimethoprim-sulfamethoxazole, chloramphenicol and vancomycin (Ethell et al 2000, Mader et al 1997, Veyries et al 2000). 

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