Insecticidal, antimicrobial, and antiviral activity of Bacillus thuringiensis ssp. kurstaki strains isolated from atmospheric aerosols in the South of Western Siberia

Abstract

The data on insecticidal, antimicrobial, and antiviral activity of Bacillus thuringiensis (Bt) strains isolated in the microbiological study of height and ground atmospheric aerosol samples taken in the South of Western Siberia are presented. Among 36 isolated bacteria determined as related to the Bt species, 15 strains were relegated to the Bt ssp. kurstaki subspecies by results of intraspecific testing and studied for the presence of antagonistic attributes. In spite of long wandering in extreme conditions in the composition of atmospheric aerosols, including higher atmospheric layer (up to 7 km), the isolated Bt ssp. kurstaki strains keep high (inherent to this subspecies) entomopathogenic activity, possessed the ability to inhibit the multiplication of such pathogenic microorganisms as Staphylococcus aureus, Salmonella thyphimurium, Shigella sonnei, Candida albicans, and others, and manifested the ability to effectively neutralize the multiplication of the A/chicken/Kurgan/05/2005 (A/H5N1) avian influenza virus and A/Aichi/2/68 (A/H3N2) human virus. Properties of Bt strains isolated from atmospheric aerosols not only verified their well known resistance to unfavorable factors of the environment but also exhibited the possibility of using them for developing viri cides.

Evaluation of the efficacy of benzothiazole against the red flour beetle, Tribolium castaneum (Herbst)

“…[12][13][14] For example, bacteria such as Bacillus thuringiensis have been reported for microbiological control of pests, especially Lepidoptera. 15,16 Spinosad, a metabolite of the actinomycete Saccharopolyspora spinosa, has been identified to provide great control for some storage pests, such as Sitophilus zeamais and Rhyzopertha dominica, but has poor efficacy for T. castaneum. 17,18 It seems that using natural products that are ecofriendly, biosafe and have insecticidal activity is a feasible method.…”

“…In recent years, plant‐derived and microbial‐derived pesticides have attracted increasing attention because they represent abundant secondary metabolites that exhibit repellent activity and insecticidal properties . For example, bacteria such as Bacillus thuringiensis have been reported for microbiological control of pests, especially Lepidoptera . Spinosad, a metabolite of the actinomycete Saccharopolyspora spinosa , has been identified to provide great control for some storage pests, such as Sitophilus zeamais and Rhyzopertha dominica , but has poor efficacy for T. castaneum .…”