Until recently, there were rare scientific reports on the biotechnological potential of non-pathogenic bacteria of the Acinetobacter genus. Although the first reports about the practically valuable properties of these bacteria date back to the 70s and 80s of the twentieth century and concerned the synthesis of the emulsan bioemulsifier. In the last decade, interest in representatives of the Acinetobacter genus as objects of biotechnology has significantly increased. The review presents current literature data on the synthesis by bacteria of this genus of high-molecular emulsifiers, low-molecular biosurfactants of glyco- and aminolipid nature, enzymes (lipase, agarase, chondroitinase), phytohormones, as well as their ability to solubilize phosphates and decompose various xenobiotics (aliphatic and aromatic hydrocarbons, pesticides, insecticides). Prospects for practical application of Acinetobacter bacteria and the metabolites synthesized by them in environmental technologies, agriculture, various industries and medicine are discussed. The data of own experimental studies on the synthesis and biological activity (antimicrobial, anti-adhesive, ability to destroy biofilms) of biosurfactants synthesized by A. calcoaceticus IMV B-7241 strain and their role in the degradation of oil pollutants, including complex ones with heavy metals, are presented. The ability of A. calcoaceticus IMV B-7241 to the simultaneous synthesis of phytohormones (auxins, cytokinins, gibberellins) and biosurfactants with antimicrobial activity against phytopathogenic bacteria allows us to consider this strain as promising for practical use in crop production to increase crop yields.

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The study provides evidence of the phage 49 abortive infection in the lysogenic culture of Erwinia horticola 450(59). Aim. To study the peculiarities of abortive infection in lysogenic system of E. horticola under the propagation of phage 49. Methods. Erwiniophage 49 was obtained by propagation on E. horticola 450(59). The phage lysates were studied by using centrifugation in CsCl-gradients, electron microscopy and SDS-PAGE of the virion polypeptides. Results. The Abi-phenotype is manifested through the reduced efficiency of virus plating and the decrease of amount of phage progeny. The phage lysates contain an excess of capsid structures, incomplete virions and polytails. The polypeptide profile of these capsid structures corresponds with the one of the native phage particles. Conclusions. The obtained data suggest that the current phage-bacterial system develops the Abi-phenotype affecting the phage morphogenesis.

Останнім часом інтерес до Pantoea agglomerans обумовлений біорізноманітністю і корисними властивостями її метаболітів. З іншого боку -необхідністю дослідження шкодочинності цієї бактерії. Мета. Дослідити інфікування рослин зернових культур видів Triticum aestivum L. і Secale cereale L. штамами Pantoea agglomerans за дії на фотохімічну та ферментативну активності фотосинтетичного апарату зернових культур. Методи. Культивування бактерій, приготування бактеріальних суспензій виконували за загально прийнятими методиками, штучну інокуляцію рослин здійснювали шляхом введення бактеріальної суспензії в стебло жита і пшениці в фазу трубкування. Фотохімічну активність листків визначали методом індукції флюоресценції хлорофілу, активність антиоксидантних ферментів -за швидкістю розкладання пероксиду водню: катала зи -перманганатометрично, а пероксидази -за реакцією із бензидином із подальшою фотометрією. Для статистичної обробки результатів використовували пакет програм MS Excel. Результати. Узагальнено дані впливу інокуляції рослин Triticum aestivum L. і Secale cereale L. фітопатогенними штамами P. agglomerans на активність антиоксидантних ферментів тканин і фотохімічну активність фотосинтетичного апарату. Виявлено найбільш істотне підвищення активності антиоксидантних ферментів листків жита за умов інфікування P. agglomerans 7460 порівняно з інтак-

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the effect of b a c i l l u s a m y l o l iq u e f a c ie n s SUBSP. PLANTARUM IMV B-7524 STRAIN exometabolites on the induction of defense reactions in winter wheat plants Aim. To study the effect o f antibiotic exometabolites o f Bacillus amyloliquefaciens subsp. plantarum IM V B-7524 strain on the induction o f defense responses in young plants o f winter wheat. Methods. Microbiological, biochemical, phytopathological, statistical. Results. It was found that, when pre-watering winter wheat plants with salicylic acid, the cell-free culture supernatant and lipopeptide fraction o f IM V B-7524 strain exometabolites during the further infection with phytopathogen Bipolaris sorokiniana, the damaged sur face area o f leaves decreased more than 10 times compared to the control. It was shown that in the roots and shoots o f winter wheat plants L-phenylalanine ammonia-lyase (PAL) activity increased about 3 times in 2 hours after treatment. Conclusion. Reduction o f the damaged surface area o f leaves by the action o f fungal phytopathogen and change o f PAL activity in plants indicate the induction o f defense responses under the influence o f antibi otic exometabolites o f B. amyloliquefaciens subsp. plantarum IM V B-7524 strain. K e y w o r d s: Bacillus amyloliquefaciens subsp. plantarum IM V B-7524, winter wheat, antibiotic exometabolites, Bipolaris sorokiniana, infected leaf area, L-phenyl-alanine ammonia-lyase, defense reactions o f plants.

Microscopic fungi synthesize a wide range of phenolic compounds that play an important role in cell wall formation, as well as perform signaling and protective functions. One of the important functions of phenolic compounds, primarily polyphenols, is antioxidant activity. The most active polyphenols are flavonoids, their synthesis in microscopic fungi has not been studied enough. The aim of the study was to determine the total phenols and flavonoids content and antioxidant activity of Talaromyces funiculosus strains isolated from different econiches. Methods. 20 strains of the microscopic fungus T. funiculosus – 10 endophytes and 10 saprotrophs were used in the experiments. Cultivation of filamentous fungi was performed under submerged conditions with shaking at 210–230 rpm in Erlenmeyer flasks containing 200 ml of Czapek liquid medium at a temperature 26±2°C for 6 days. The biomass of the strains was filtered, dried at 70°C and extracted with 95% methanol (1:50 w/v). The total phenols content was determined using Folin-Ciocalteu reagent by the method of Arora, Chandra (2010) with some modifications and expressed as mg of gallic acid equivalents (GAE) per g of dry weight mycelium. Flavonoids in each extract were determined spectrophotometrically with AlCl3 and expressed as mg of quercetin equivalents (QE) per g of dry weight mycelium. Antioxidant activity of methanolic extracts was measured as radical scavenging activity by the percentage inhibition of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Results. The total phenolic content of methanolic extracts of T. funiculosus strains ranged from 0.12±0.007 to 1.97±0.150 mg GAE/g. The highest level of phenolic compounds was found for saprotroph UCM F-16790 (1.97±0.150) and endophyte UCM F-16795 (1.71±0.137 mg GAE/g). The flavonoid content in methanolic extracts of the studied strains varied in the range of 0.02±0.001–0.39±0.041 mg QE/g. All studied strains of T. funiculosus showed antioxidant activity against DPPH radical, which was 12.19±2.34–60.37±7.24% inhibition. Statistical analysis revealed a strong positive correlation between the total phenols and flavonoids content (Pearson’s correlation coefficient r=0.92); between antioxidant activity, phenols (r=0.82) and flavonoids (r=0.81) content in methanol extracts of T. funiculosus strains. The total content of phenols and flavonoids and antioxidant activity did not depend on the trophic group of the studied strains. The moderate correlation between flavonoids content and antioxidant activity of methanolic extracts of endophytic T. funiculosus strains (r=0.46) may be related to their ability to synthesize a wider range of polyphenolic compounds with antioxidant activity. Conclusions. The studied T. funiculosus strains have the ability to synthesize phenolic compounds and flavonoids in different concentrations. Correlation analysis revealed strong correlations between total phenolic and flavonoid contents and antioxidant activity. The reason for phenomenon of moderate correlation (r=0.46) between flavonoid content and antioxidant activity in endophytic strains may be the synthesis of other compounds by individual strains. The determination of individual components synthesized by the most active strains is of scientific interest for further study. T. funiculosus UСM F-16795 and UСM F-16790 strains had a quite high level of phenols and flavonoids. Obtained data may be promising for the search for phenolic compounds with antioxidant properties to increase plant resistance to negative impacts of environmental stress factors.