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4-Chloro-2-phenylphenol 2-Benzyl-4-chlorophenol (MCOPP) organisms but against Gram-negative bacteria the factor is only one-fiftieth. Octylphenol is also fungistatic, and has been used as a preservative for proteinaceous products, such as glues and nonfood gelatins. Its activity is reduced in the presence of some emulgents, a property that might render it unsuitable for the preservation of soaps and cutting oils. 2.5.2 2-Phenylphenol (2-phenylphenoxide) This occurs as a white crystalline...

Derivatives of imidazole

Imidazolines (Fig. 2.29) are 2,3-dihydroimida-zoles 2-heptadecyl-2-imidazoline was introduced as an agricultural fungicide as far back as 1946. Other derivatives containing the imidazole ring have recently found successful application as preservatives. Two are derivatives of 2,4-dioxote-trahydroimidazole, the imidazolidones the parent diketone is hydantoin. A 55 solution of this compound (Fig. 2.29) is available commercially as Glydant (Lonza U.K. Ltd., Cheltenham, U.K.). This product is...

Types of antimicrobial agents

2.1 Sources of phenols the coal-tar industry 2.2 Properties of phenolic fractions 2.3 Formulation of coal-tar disinfectants 2.4 The modern range of solubilized and emulsified 2.4.1 Cresol and soap solution British Pharmacopoeia (BP) 1963 (Lysol) 2.5.2 2-Phenylphenol (2-phenylphenoxide) 2.6.2 Pentachlorophenol (2-phenylphenoxide) 2.6.3 4-Chloro-3-methylphenol (chlorocresol) (chloroxylenol para-chloro-meta-xylenol PCMX) DCMX) 2.6.6 4-Chloro-3-methylphenol (para-chloro-meta-cresol PCMC) 2.6.8...

Other chelating agents

Chelating agents other than EDTA are described chemically in Fig. 2.25, and some of their properties (based in part on the excellent book of West, 1969) are listed in Table 2.11. While EGTA forms a stronger complex with Ca than does EDTA, for most other metals, except Ba and Hg, it is a weaker complexing agent than EDTA. Notably, there is a divergency of 5.79 log K units between the stability constants of the Ca and Mg complexes with EGTA (West, 1969). Compared with EDTA, CDTA has superior...

Info

Contact time 10min at room temperature. Neutralizer egg-yolk medium. Inoculum 105 in distilled water. Contact time 10min at room temperature. Neutralizer egg-yolk medium. function ensues, with precipitation of intracellular constituents leading to a bactericidal effect. Because of the residual positive charges on the polymer, PHMB is precipitated from aqueous solutions by anionic compounds, which include soaps and detergents based on alkyl sulphates. It is also...

Essential oils

Essential oils have been used empirically throughout history as preservatives. Their re-examination as antimicrobial agents has received attention from many workers, as their use as natural preservatives has contemporary appeal. Melaleuca alternifolia (tea tree) oil has been included increasingly in consumer products as an antimicrobial agent. Studies have shown that Tea tree oil is an effective antimicrobial agent demonstrating activity against methicillin-resistant Staph, aureus (Carson...

Historical introduction

Throughout history it is remarkable how hygienic concepts have been applied. Examples may be found in ancient literature of the Near and Middle East, which date from when written records first became available. An interesting example of early written codes of hygiene may be found in the Bible, especially in the Book of Leviticus, chapters 11-15. Disinfection using heat was recorded in the Book of Numbers, in which the passing of metal objects, especially cooking vessels, through fire was...

Peracetic acid

Peracetic acid, CH3-COOOH, was introduced as an antibacterial agent in 1955. It is available commercially as a 15 aqueous solution, in which an equilibrium exists between peracetic acid and its decomposition products acetic acid (CH3-COOH) and hydrogen peroxide. Peracetic acid solution has a broad spectrum of activity, including bacteria and their spores, moulds, yeasts, algae and viruses. It finds extensive use in the food industry and for disinfecting sewage sludge. It is a powerful oxidizing...

Derivatives of hexamine

Hexamine (hexamethylene tetramine 1,3,5,7-tri-aza-l-azonia-adamantane) has been used as a urinary antiseptic since 1894. Its activity is attributed to a slow release of formaldehyde. Other formaldehyde-releasing compounds are considered in sections 7.2.4,17.2,17.5 and 17.6. Wohl in 1886 was the first to quaternize hexamine, and in 1915-16 Jacobs and co-workers attempted to extend the antimicrobial range of hexamine by quaternizing one of its nitrogen atoms with halo-hydrocarbons (Jacobs &...

Peroxygens 121 Hydrogen peroxide

Hydrogen peroxide (H202) is a familiar household antiseptic. It was discovered in 1818 and was early recognized as possessing antibacterial properties. These were extensively investigated in 1893 by Traugott. Hydrogen peroxide is available as a solution designated as 20- or 10-volume, a means of indicating its strength by describing the volume (20 or 10, respectively) of oxygen evolved from 1 volume of the peroxide solution. Strengths for industrial use of 35, 50 or 90 are available. Hydrogen...

Contents

List of contributors, vii Preface to the fourth edition, ix Preface to the first edition, x 1 Historical introduction, 3 Adam P Fraise 2 Types of antimicrobial agents, 8 Suzanne L Moore and David N Payne 3 Factors influencing the efficacy of antimicrobial agents, 98 4 Biofilms and antimicrobial resistance, 128 Peter Gilbert, Alexander H Rickard and Andrew J McBain 5 Mechanisms of action of biocides, 139 Peter A Lambert 6.1 Intrinsic resistance of Gram-negative bacteria, 154 6.2 Acquired...

List of contributors

Jeremy Bagg PhD FDS RCS Ed FDS RCPS Glasg FRCPath Professor of Clinical Microbiology University of Glasgow Dental School Glasgow, UK Rosamund M Baird BPharm PhD MRPharmS School of Pharmacy University of Bath Bath, UK Laboratory Manager Hospital Infection Research Laboratory City Hospital Birmingham, UK Reading Public Health Laboratory Reading, UK Stephen P Denyer BPharm PhD FRPharmS Head of School Welsh School of Pharmacy Cardiff University Cardiff, UK Department of Bacteriology and Virology Sp...