Fig. 4.

a - f Average effective virus-inhibiting concentration (EC₅₀,mg/ml) of preprarations against influenza virus strains H3N2 (a), H1N1 (b), H5N3 (c), H7N1 (d) and PMV-1/Beadette (e), Sendai. strain 960 (f). Virus-inhibition activity of preparations obtained from extremophilic actinomycetes against Influenza virus H3N2 in dose 100 EID₅₀/ml. The specific virus-inhibitory activity of the studied preparations was determined in accordance with the guidelines of the “Pre-clinical Drug Research Guide” [21, 22]. Various doses of extract preparations were mixed with an equal volume of 100 EID50/ml of the tested virus. After 30 min of incubation at 370 С, the mixture was inoculated into the chorionic-allantoic cavity of 10-days old chicken embryos. Viruses were grown for 24–72 h at 370С depending on the viral strain. The presence of the viruses was indicated by the hemagglutination test (HA-test). The ability of investigated preparations to inhibit virus infectious activity was estimated by comparison of the results of HA-test in experimental and control samples. As a control, the buffered saline pH 7.2, was used and the allantoic fluid with viruses but without the addition of preparations obtained from extremophilic actinomycetes