The effect of selenium biocomposites obtained from medical macrobasidiomycetes Ganoderma lucidum, Grifola umbellata, Laetiporus sulphureus, Lentinula edodes, and Pleurotus ostreatus on the viability of the phytopathogenic gram-positive bacteria Clavibacter michiganensis subsp. sepedonicus (Cms) and its ability to form biofilms has been studied. A decrease in the viability of the bacterial cells as a result of incubation with biocomposites is shown. The determining effect of the selenium component of the composites on the studied biological activity is investigated. The dependence of the antimicrobial action of selenium-containing experimental samples on the biological species of the fungus is revealed. Biocomposites based on extracellular metabolites of Lentinula edodes and Ganoderma lucidum possess maximal activity. When biopolymer samples of fungal origin are added to the bacterial suspension, the ability of Cms to form biofilms differs depending on the type of biocomposite; it decreases significantly in some cases.

The impact of selenium biocomposites obtained from the medicinal macrobasidiomycetes Ganoderma lucidum, Grifola umbellata, Laetiporus sulphureus, Lentinula edodes , and Pleurotus ostreatus on the viability and biofilm formation capability of the phytopathogenic Gram-positive bacterium Clavibacter michiganensis ssp. sepedonicus (Spieck. et Kotth.) ( Cms ) was studied. Impairment of bacterial cell viability resulting from their incubation with biocomposites was shown. The decisive role of the composites’ selenium component on the biological activity under question was established. The dependence of antimicrobial effect of the selenium-containing specimen on the mushroom systematic position was revealed. The maximal activity was found for the biocomposites based on the extracellular metabolites of L. edodes and G. lucidum . When the biopolymer specimen of fungal origin was added to bacterial suspension, the Cms capability of forming biofilms was found to be distinctly dependent of the biocomposite type, and it was substantially reduced in a number of cases.

Biochemical investigations of 3-substituted chromen-2-ones (coumarins) and those condensed with biologically active azaheterocycles assessed their toxic effects and influence on the blood-coagulation system. The studied group of compounds behaved in the initial time period like the well-known anticoagulant warfarin and exhibited insignificant toxic effects.

Аннотация. На примере ряда культур ксилотрофных базидиомицетов разных

Effect of selenium-containing biocomposites obtained from submerged cultures of macrobasidiomycetes Ganoderma applantum, G. cattienensis, G. colossus G. lucidum, G. neojaponicum, and G. valesiacum, on plant pathogenic bacteria Clavibacter michiganensis ssp. sepedonicus (Cms), Micrococcus luteus, Pectobacterium atrosepticum, Pectobacterium carotovorum subsp. carotovorum, Pseudomonas fluorescens, Pseudomonas viridiflava, and Xanthomonas campestris was studied. Oxopropyl-4-hydroxychromenones were used as components of the fungal nutrient media. The bacteriostatic and bactericidal activity of the Se-containing and Se-free substances of fungal origin against plant pathogenic bacteria was determined using colony-forming units count, the agar well diffusion method, and by turbidity measurements of bacterial suspensions. The composites produced from the extracellular metabolites of G. cattienensis SIE1302 with 4-hydroxy-3-(3-oxo-1,3-diphenyl propyl)-chromen-2-one (S(45)), and of G. lucidum SIE1303 with 4-hydroxy-3-(3-oxo-1-(3-nitrophenyl)-3-phenylpropyl)-chromen-2-one (S(NO2)) possessed the most pronounced antibacterial action against Cms. The composites produced from the isolates of G. valesiacum 120702 with S(NO2) showed the maximal antibacterial activity against Xanthomonas campestris B-610. High antimicrobial effect of G. lucidum 1315 with S(NO2) against Xanthomonas campestris B-610 and of G. colossus SIE1301 against Pseudomonas fluorescens EL-2.1 was revealed. The pioneering information on the biological activity of coumarin series compounds in their application for producing the substances of fungal origin was obtained.

The results of studying the effect of biologically obtained selenium nanocomposites on the bacterium Clavibacter michiganensis ssp. sepedonicus (Cms) are presented. Cms is a Gram-positive bacterium, which causes one of the most dangerous potato diseases, ring rot. The effective alongside ecologically safe methods for combating Cms are lacking. As the agents feasible for use in this purpose, we examined the selenium nanocomposites obtained from the macrobasidiomycetes' submerged cultures. For exploring the bionanocomposites effect on Cms, the methods of agar well diffusion, the suspension turbidity measurement, and the colony-forming units count were applied. The results showed that all the nanocomposites under study lowered the bacterial suspension's absorption values compared to the reference specimen, that testified to the observation of bacteriostatic effect of the agents tested. The suppression action of nanocompostes was elucidated by means of both agar well diffusion assay and colony-forming units count. Thus, the results obtained demonstrate the occurrence of bacteriostatic and bactericidal effects of the substances under study, and favor the supposition on advisability of further research into the selenium nanocomposites as the agents for agricultural recovery from the bacterial pathogens.

Concise outline of the chemical components of the representatives of five species of Ganoderma mushroom is presented. The fungal isolates collected from different areas of Vietnamese National Parks (Ganoderma colossus, G. neojaponicum, G. cattienensis, G. lucidum, G. applanatum) serve as a source of collection cultures. Three additional herbarium strains of Ganoderma from Russian regions are implemented in the present framework for the purposes of comparison. Low-molecular-weight constituents of the mycelia are characterized by means of the GC-MS and GLC techniques as variants of gas chromatographic analysis. In the pigmented mycelium on solid media, and in the submerged mycelial cultures under varied growth conditions, several valuable lipidic substances are detected. Those are of promising biotechnological applications including the food supplement, biodiesel-related items, and lipid-based drug delivery systems. The peculiarities of fatty-acid composition of several species' mycelia are quite interesting for taxonomy studies. Thus, only G. neojaponicum is characterized by the high level of fatty acid with an odd number of carbon atoms C-15:0 along with the presence of C2-OH (16:0) hydroxyacid. Exclusively G. cattienensis shows the presence of 3-hydroxyacid C3-OH (14:0). Finding the 3-hydroxyacids (C3-OH (12:0) and C3-OH (14:0), therewith in only two species just mentioned) is uncommon for higher fungi, and could be useful for chemosystematics.