Microbicidal compound

Natural high-molecular weight sulphated or sulphonated PS, such as cellulose sulphate and dextran sulphate, may be useful non-toxic microbicidal compounds that are active against a variety of sexually-transmitted disease agents, including bovine papillomavirus type 1 and human papilloma virus type 11 and type 40 [111],... 

As a rule it has to be stated that halogenated alkylphenols are more active and broader in effectiveness than the alkylphenols. It is therefore in no way astonishing that some of the most important phenol derivatives in practical application are found in this class of phenolics. Among others Klarmann et al. (1933) have carried out systematic examinations of the relationship between chemical structure and antimicrobial activity with regard to halogenated alkylphenols. However, one should not overestimate the value of the data obtained when decisions and selections have to be made for practical application, as other properties of the microbicidal compounds, such as water-solubility, partition coefficient, activity in the presence of interfering factors encountered in practice, and toxicity, are of the same or of even more importance. Although there are available a lot of data and experience, often the optimum compound and formulation must be determined by experiment. 

Biological Aspects.—The modes and rates of dissipation of the two microbicidal compounds 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (both calcium chloride addition compounds) over a range of environmental conditions have been studied, and the degradation products identified. ... 

Further to these results, the microbicidal activities of FIBCIDE-KF and KATHON WT were evaluated. The minimum inhibitory concentrations (MIC) for Pseudomonas aeruginosa, Pseudomonas putida, Bacillus subtilis and Microbacterium sp. are identical for both compounds, so the microbicidal effect has not diminished (Figure 10). It appears that the biocidal effects are similar because the Cl-MIT in the inclusion complex is released into water, as shown in Figure 6. 

The ability of halogens to form chemical compounds with all metals and most nonmetals has led to a wide variety of uses for these elements. Chlorine is used as a bleach and a disinfectant. Iodine has been used as a topical microbicide. Iodine and bromine are added to halogen lamps to lengthen... 

A number of reports have suggested that sulfated compounds, such as DS, bind the V3 loop of X4 viruses more readily than they bind the loop of R5 viruses [76]. Consistent with this is the demonstration that DS fails to inhibit R5 strains in vitro [75]. Because the envelope of R5 viruses is less positively charged than that of X4 viruses [77,78], there is controversy over whether sulfated polymers will be effective in blocking R5 viruses. Ability to block R5 viruses is critical for a microbicide, because even if both phenotypes are transmitted together, it is the R5 viruses that are amplified during the initial infection [79,80]. 

Taking into account the above considerations, the SPs were suggested to be ideal microbicides for topical use [105]. A number of potential candidate microbicides have been shown to inhibit virus attachment, fusion, and entry into host target cells for sexually transmitted infections. These include cellulose sulfate, poly(styrene 4-sulfonate), polystyrene sulfonate, polymethylene-hydroquinone sulfonate, naphthalene sulfonate polymer, and a carrageenan derived from seaweed (Carraguard) that may prevent viral entry. Several candidate compounds have already progressed to various stages of clinical trials [106]. Currently, some of them have been formulated and are in phase II/III clinical trials. 

---