Effect of Selenium-containing Biocomposites from Medicinal Mushrooms on the Potato Ring Rot Causative Agent.

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.

[Effect of Selenium-Containing Biocomposites Based on Ganoderma Mushroom Isolates Grown in the Presence of Oxopropyl-4-Hydroxycoumarins, on Bacterial Phytopathogens].

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 Sefree 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.