ABSTRACT
The ability of 30 compounds to protect infection bacteria and baculoviruses from the damaging effect of ultraviolet (UV) irradiation was investigated. For this B. thuringiensis var. israelensis spores and gypsy moth (Lymantria dispar L.) nuclear polyhedrosis virus were mixed with different components and exposed to UV irradiation at 0.25 WI cm2 for 60 min. Then spore viability and viral pathogenicity were studied in third instar gypsy moth larvae. The composition comprising sodium alginate, albumin, and ascorbic acid ensured the most effective protection of the viruses and bacteria. These components were shown to provide protection from exposure to UV irradiation even at a low concentration. Their incorporation into biopesticides will assist in enhancing the efficiency of their use.
Subject(s)
Moths , Pest Control, Biological/methods , Radiation-Protective Agents , Alginates , Animals , Bacillus thuringiensis/radiation effects , Baculoviridae , Chitosan , Glucuronic Acid , Hexuronic Acids , Moths/microbiology , Moths/virology , Nucleopolyhedroviruses/radiation effects , Spores, Bacterial/radiation effects , Starch/analogs & derivatives , Ultraviolet RaysABSTRACT
AIM: To study antiviral activity of extracts obtained from basidial fungi against influenza viruses of different subtypes. MATERIALS AND METHODS: Antiviral activity of extracts obtained from basidial fungi against influenza virus A/chicken/Kurgan/05/2005 (H5N1) was determined in in vitro experiments. Changes in infectiousness of pandemic influenza virus A/Moscow/226/2009 (HIN1)v caused by extracts of basidial fungi was studied in experiments in vitro and in vivo. RESULTS: Seventy water extracts of basidial fungi were studied, of which 10 were able to inhibit infectiousness of influenza virus strain A/ chicken/Kurgan/05/2005 (H5N1) in MDCK cell culture. Also, several studied extracts decreased infectiousness of pandemic influenza virus strain A/ Moscow/226/2009 (H1N1)v in MDCK cells and inhibit its reproduction in lungs of infected mice. CONCLUSION: High antiviral activity of extracts obtained from basidial fungi against influenza viruses opens perspectives for development of drugs with preventive and treatment effects.
Subject(s)
Antiviral Agents/pharmacology , Basidiomycota/chemistry , Complex Mixtures/pharmacology , Influenza A Virus, H1N1 Subtype/metabolism , Influenza A Virus, H5N1 Subtype/metabolism , Influenza, Human/drug therapy , Orthomyxoviridae Infections/drug therapy , Animals , Antiviral Agents/chemistry , Complex Mixtures/chemistry , Dogs , Humans , Influenza A Virus, H1N1 Subtype/growth & development , Influenza A Virus, H5N1 Subtype/growth & development , Influenza, Human/virology , Mice , Mice, Inbred BALB C , Orthomyxoviridae Infections/virologyABSTRACT
The paper considers horizontal transmission routes of baculovirus infection in the gypsy moth (Lymantria dispar L.). The original method for modeling natural processes in controllable conditions allowed one to estimate the influence of factors on the occurrence of epizooties. The authors investigated 3 possible models of virus transmission from infected to uninfected gypsy moths: 1) infected and test caterpillars were kept and fed together (a complex route); 2) those which were in the immediate vicinity, but deprived of eating together (an aerial route); 3) test caterpillars were fed on the leaves on which infected caterpillars had eaten (an oral route). The investigations have shown that the complex and oral routes out of the considered models may be considered to be effective infection transmission routes for the horizontal spread of epizooties. Furthermore, the availability of sufficient amount of infected caterpillars in the population leads to a reduction in the resistance of healthy insects to other diseases. Thus, by taking into account the capacity of larvae for passive migration, the purpose of insecticidal treatment is to set up a few infection foci that will be a source for the spread of epizootias and contribute to an overall viability reduction of a pest population.
Subject(s)
Baculoviridae , Insect Control/methods , Moths/virology , Animals , Larva/virologyABSTRACT
Sixty preparations of basidiomycetes (Ganoderma, Lentinus, Pleurotus, Laetiporus, Polyporus, Inonotus, Flammulina, Grifola, Trametes) were investigated with respect to their toxicity for Vero cells and antiviral activity. The antiviral activity was estimated with the use of the West Nile virus and type 2 Herpes simplex. It was shown that 11 preparations of Ganoderma, Lentinus and Pleurotus completely inhibited the infective activity in doses not lower than 1000 TCD50 (the West Nile virus) and 100 PPU (type 2 Herpes simplex). The antiviral activity of the preparations was likely due to the content of polysaccharides or their derivatives in the composition. It increased with increasing of the quantity of the total polysaccharide fraction or its concentration.
