Germicidal activity

Alkylbenzyldimethyl quaternaries (ABDM) are used as disinfectants (49) and preservatives. The most effective alkyl chain length for these compounds is between 10 and 18 carbon atoms. Alkyltrimethyl types, alkyl dimethylbenzyl types, and didodecyl dimethyl ammonium chloride [3401-74-9] exhibit excellent germicidal activity (151—159). Dialkyldimethyl types are effective against anaerobic bacteria such as those found in oil wells (94—97). One of the most effective and widely used biocides is didecyl dimethyl ammonium chloride [7173-57-5]. 

Germicidal Properties. The germicidal activity of aqueous chlorine is attributed primarily to HOCl. Although the detailed mechanism by which HOCl kills bacteria and other microorganisms has not been estabUshed, sufficient experimental evidence has been obtained to suggest strongly that the mode of action involves penetration of the cell wall followed by reaction with the enzymatic system. The efficiency of destmction is affected by temperature, time of contact, pH, and type and concentration of organisms (177). 

PhenoHc dispersions made using natural soaps are sensitive to hard water, but under proper formulation they can tolerate water of 400 ppm total hardness and maintain complete clarity and germicidal activity. The highest activity for phenols was found when using secondary alkane sulfonates as solubilising agents (75). 

Consider using quaternary ammonium compounds if the product is intended to be used at pH = 8-9 and in the absence of anionics, proteins, and milk residues. Their germicidal activity increases in the order of monomer = dimer < trimer < tetramer < polymer, with a peak of efficacy for C12 - C16 compounds [17],... 

While studying antiseptic and germicidal activity in the thiophene series, several quaternary thenylamines were prepared by the following method (54) ... 

Phenolic compounds typically possess anti-diarrheal and anti-motility properties germicidal activity , herbicidal effect and antiseptic properties". They have also been used in the tanning of leather , as dyes , as a thermal insulating material, as food aroma and liquid smoke". In some cases, the smoke flavour has been attributed to the presence of phenols and sometimes to a single component. The phenols forming the "liquid smoke" which is used to smoke foods are well studied but their role and extent of flavouring have been clarified recently . ... 

Guha G., D. Das P.D. Grover, Guha, B.K. (1987) Germicidal Activity of Tar Distillate Obtained from Pyrolysis of Rice Husk. Biol. Wastes. 21, 93-100,... 

PVP-I also has been reported to give better penetration of eschar [12,60] and to maintain germicidal activity in the presence of blood, serum, or pus that is superior to that of several other topical antimicrobials [30]. With regard to the... 

RCS Woodroffe. A respirometer technique for extimating germicidal activity on skin. J Hyg Cambr 61 283, 1963. 

Many topicals require the addition of water to prepare their use dilution, but product labels often do not clearly specify the type of water to be used for this purpose. Normally, one would use tap water for this purpose, but label claims for germicidal activity may be based on distilled water as the product diluent. Current regulations in the United States assume that distilled water is used and do not require that this be stated on the label. Consumers are usually unaware of the need to use distilled water. 

Testing Using the Umbilical Cord as a Model for Mucous Membranes. The topography, moisture level, microbial ecology, and surface temperature of mucous surfaces are quite different from those of skin. It would, therefore, be safe to assume that the behavior of microbial pathogens on mucous membranes may also be different from that on skin. Each of these differences may also influence the germicidal activity of an antiseptic applied to mucous membranes. 

---