Viricide activities

Although many papers have been published on the virucidal (viricidal) activity of biocides there is little information available about the uptake of bioeides and their penetration into viruses of different types, or of their interaction with viral protein and nucleic acid. 

J-Y MaiUard, AD Russell. Viricidal activity and mechanisms of action of biocides. Sci Prog 80 287-315, 1997. 

Some secondary metabolites of lichens were also reported to have antiviral effects. Perry and coworkers in 1999 reported the antiviral activity of ( )-usnic acids (50 and 51) against the Poho and Herpes simplex type 1 viruses [63]. The viricidal activity of parietin (3), a secondary metabolite of Teloschistes chrysophthalmus (L.) Th. Fr., was reported against Junin and Tacaribe arena viruses [85]. Tobacco mosaic virus inhibition potential of lichenan (73), a metabolite of many lichens, was also reported in the literature [86]. Usnic acid (50) was also reported to exhibit activity against same viruses as tested for parietin (3) [6] (Table 3). 

Adansonia digitata root-bark and leaf methanol extracts have shown high antiviral activity (against Herpes simplex, Sindbis and Polio), together with viricidal (direct inactivation of virus particles) and also intracellular antiviral activity, which could indicate the presence of multiple antiviral compounds, or a single compound with multiple actions (17, 27). Whether such studies will show... 

Among disinfectants, such as inorganic chloramines, chlorine and chlorine dioxide, the latest is the most efficient disinfectant for bacteria, having both the lowest effective dose and the shortest contact time [16], but human health problems can arise with its use [31]. Increasing pH increases the bactericidal activity of chlorine dioxide [32]. However, at higher pH values (> 7.0) chlorine becomes less effective because hypochlorite ions are formed. Increased pH levels (> 7.5) also convert dichloramines to monochloramines which are less bactericidal [16]. On the other hand, monochloramines are more efficient viricides than dichloramines [33]. 

---