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Документ Industrial wastes as substrates for synthesis of surfactants with antiadhesive activity by Rhodococcus erythropolis IMV Ac-5017(2022) Pirog, Tatiana; Kliuchka, Igor; Kliuchka (Nykytyuk), LiliaMicrobial surfactants can affect the degree of microorganism’s adhesion to different surfaces and lead to biodegradation of the already formed biofilms. They are also non-toxic to the environment. These properties allow to use the microbial surfactants in medicine and food industry.Документ Synergistic effect of surfactants of Nocardia vaccinii IMV B-7405 and essential oils on Candida genus yeast(2022) Pirog, Tatiana; Kliuchka (Nykytyuk), Lilia; Shevchuk, Tetiana; Muchnyk, FainaThe increase in the number of resistant strains of Candida genus representatives, capable of forming biofi lms on various surfaces, stimulates the search for new, alternative methods of combating them, one of which is the use of compounds of natural origin, such as essential oils. However, at the same time, their concentration should be minimal, which is due to the ability of essential oils to cause severe damage of the human’s central nervous system and aspiration pneumonia. This leads to the necessity of searching for new methods to reduce the concentration of essential oils and at the same time to preserve their properties, in particular, by their use in a mixture with other antimicrobial agents, which can be microbial surfactants. Previously, it was found that the degree of yeast biofi lm destruction under the action of Nocardia vaccinii IMV B-7405 surfactants dependson the nature of the growth substrate and is the highest in the presence of preparations synthesized on purified glycerol. Aim. To study the synergism of antifungal activity and the role in the destruction of biofilms of a mixture of Nocardia vaccinii IMV B-7405 surfactants synthesized on glycerol of different quality and essential oils. Methods. N. vaccinii IMV B-7405 was grown in a medium containing purified glycerol or waste from biodiesel production at a concentration of 2% (v/v) as carbon sources. The surfactants were extracted from the supernatant of cultural liquid by a modified Folch mixture. The antimicrobial activity of essential oils, surfactants, and their mixtures was determined by the index of the minimum inhibitory concentration. To assess the synergistic effect of a mixture of surfactants with essential oils, the fractional inhibitory concentration index was used. The degree of biofi lm destruction (%) was determined as the difference between the cell adhesion in untreated and treated with surfactants, essential oil, or their mixture wells of the polystyrene microplates. Results. It was found that the surfactants synthesized by N. vaccinii IMV B-7405 on both purifi ed glycerol and waste from biodiesel production showed synergistic antifungal activity in mixtures with cinnamon and lemongrass essential oils. Thus, the minimum inhibitory concentrations against Candida albicans D-6, Candida utilis BVS-65, and Candida tropicalis RE-2 of a mixture of surfactants synthesized on purified glycerol with cinnamon and lemongrass essential oils were 1.8—7.5 and 3.7— 15 μg/mL, respectively, and were lower than in the case of using surfactants (30-60 μg/mL), cinnamon or lemongrass essential oil (156—312 μg/mL) alone. The use of a mixture of surfactants obtained on waste from biodiesel production and cinnamon or lemongrass essential oils made it possible to reduce the minimum inhibitory concentrations of the latter against studied yeast test cultures by 14—56 times. At the same time, the index of fractional inhibitory concentration did not exceed 0.5, which indicates the synergism of the antifungal activity of the mixture of these compounds. The destruction of Candida yeast biofi lms under the action of surfactants synthesized on both purified glycerol and waste from biodiesel production in a mixture with cinnamon or lemongrass essential oils reached 60—67 and 67—77%, respectively, which is an average of 25—35% higher compared to the use of each monopreparation separately. Conclusions. The results presented in this paper confirm the previously obtained data that N. vaccinii IMV B-7405 surfactants, synthesized on both traditional substrates and toxic industrial wastes, have antimicrobial and antiadhesive synergistic action with essential oils, which allows us to consider them as potential components of the so-called «antifungal locks» in the fight against of Candida genus representatives.Документ Destruction of biofilms on silicone tubes under the action of a mixture of Nocardia vaccinii IMV B-7405 surfactants with other biocides(2021) Pirog, Tatiana; Kliuchka (Nykytyuk), Lilia; Shevchuk, Tetiana; Iutynska, GalynaThe formation of pathogenic microorganisms biofilms on the central venous catheter is the cause of catheter-associated infections. An alternative method of combating biofilms is the use of “antibacterial” and “antifungal” locks, which are solutions of antibiotics or antifungal drugs in a mixture with other natural compounds, which can be microbial surface-active substances (surfactants) or essential oils. Aim. To investigate the role of Nocardia vaccinii IMV B-7405 surfactants mixture with other antimicrobial compounds in the destruction of biofilm on silicone tubes. Methods. N. vaccinii IMV B-7405 was grown in medium containing as carbon source purified glycerol and waste from biodiesel production, refined sunflower oil, oil after frying French-fried potatoes, Potato wedges and meat. The surfactants were extracted from supernatant of cultural liquid by modified Folch mixture. 2 mL of surfactant solutions, antifungal drugs (nystatin, fluconazole) or tea tree essential oil of the same concentration (5–640 μg/mL) were added to test tubes with silicone tubes (with pre-formed biofilm from test culture). To study the synergistic effect of the biofilms destruction, a mixture of surfactant solutions and antifungal substances (or essential oil) of the same concentration in a ratio of 1:1 (1 mL of each solution) was added to the test tubes. Sterile tap water (2 mL) was added to control test tubes instead of surfactants preparations, antifungal substances or essential oil. The degree of biofilm destruction (%) was determined as the difference between the adhesion of cells on the inner side of silicone tubes, untreated and treated with surfactants, antifungal drugs, essential oil, or their mixture. Results. It was found that surfactants synthesized by N. vaccinii IMV B-7405 on all substrates showed synergism of yeast and bacterial biofilms destruction on silicone tubes in a mixture with nystatin, fluconazole and tea essential oil in the whole range of investigated concentrations (5–640 μg/mL), but the highest effect was achieved at a concentration of 20–40 μg/mL. Thus, the degree of Candida albicans D-6, Candida utilis BVS-65 and Candida tropicalis PE-2 biofilms destruction under the action of a mixture of surfactants synthesized on waste from the biodiesel production and waste oil, with antifungal drugs was 45.8–71.8 % and was higher than with only surfactants (21.2–41.6 %), nystatin (22.4–24.1 %) or fluconazole (28.1–31.3 %). The destruction of Candida genus yeast biofilms under the action of surfactants synthesized on oil-containing substrates in a mixture with both nystatin and fluconazole reached 50.1–71.2 %, which is 10–30 % higher compared to the use of surfactants alone or only antifungal agents. The degree of Pseudomonas sp. MI-2, Escherichia coli IEM-1, Staphylococcus aureus BMS-1, Bacillus subtilis BT-2 (spores) biofilms destruction on silicone tubes treated with a mixture of tea tree essential oil and surfactants synthesized on all oil-containing substrates was 10–29 % higher than in the case of using only solutions of surfactants (11.5–45.4 %) or essential oil (21.4–34.5 %) for the tubes treatment. Conclusions. The data obtained make it possible to consider surfactants synthesized by N. vaccinii IMV B-7405 on a wide range of cheap and accessible substrates as promising components of “antibacterial” and “antifungal” locks in combination with essential oils and antifungal agents.Документ Synthesis and biological activity of Аcinetobacter calcoaceticus IMV B-7241 surfactants depending on monovalent cations content in cultivation medium(2021) Pirog, Tatiana; Lutsay, Dariya; Shevchuk, Tetiana; Iutynska, GalynaMicrobial surfactants (biosurfactants) are multifunctional preparations due to a combination of physicochemical (reduction of surface and interfacial tension, emulsifying activity) and biological (antimicrobial and antiadhesive activity, the ability to destroy biofilms) properties. However, the disadvantage of biosurfactants synthesized as a complex of compounds is the possibility of changing the biological activity depending on the conditions of producer cultivation. Aim. To study the effect of potassium and sodium cations on the NADP+-dependent glutamate dehydrogenase activity of cell-free extract of Acinetobacter calcoaceticus ІМV B-7241 with subsequent appropriate modification of the nutrient medium composition and determination of antimicrobial and anti-adhesive activity of surfactant synthesized. Methods. A. calcoaceticus ІМV B-7241 strain was grown in media containing 2% of sunflower oil waste as a carbon source, as well as various concentrations of potassium and sodium chloride (basal – 1.0 g/l NaCl, medium # 1 that did not contains NaCl, medium # 2 in which the concentration of NaCl was 2.0 g/l, medium # 3 in which the concentration of NaCl and KCl was 1.0 g/l each). The surfactants were extracted from the supernatant liquid culture with a modified Folch mixture. Anti-adhesive activity and the degree of biofilms degradation were determined by spectrophotometric method, antimicrobial activity − by the indicator of the minimum inhibitory concentration (MIC). Activity of enzymes of surface-active aminolipids biosynthesis (NADP+-dependent glutamate dehydrogenase) and glycolipids (phosphoenolpyruvate (PEP) carboxylase, PEP-synthetase, PEP-carboxykinase, trehalose phosphate synthase) were analyzed in cell-free extracts obtained after the destruction of cells by ultrasound. Results. It was found that potassium and sodium cations in concentrations of 50 and 100 mM are inhibitors of NADP+-dependent glutamate dehydrogenase, and in lower concentrations (5–20 mM) – activators of this enzyme, as well as PEP-carboxykinase and PEP-synthetase. The increase in the biosurfactant concentration to 6.1−7.7 g/l during cultivation of A. calcoaceticus ІМV B-7241 in medium # 1 and # 3 was due to the predominant synthesis of glycolipids under such conditions, which was evidenced by the increase in 1.8−6.5 times in the activity of PEP-carboxylase, PEP-carboxykinase, PEP-synthetase and trehalose phosphate synthetase compared to the indicators on the basal medium. The concentration of surfactants synthesized in the basal medium was 3.6 g/l, but such surfactants were characterized by the highest antimicrobial and anti-adhesive activity. Their MIC against the test-cultures of studied bacteria (Pseudomonas sp. MI-2, Bacillus subtilis BT-2, Escherichia coli IEM-1, Staphylococcus aureus BMS-1, Enterobacter cloaceae C-8) and fungi (Candida albicans D-6, Rhizopus nigricans P1, Aspergillus niger P-3, Fusarium culmorum T-7) were 0.88−56 μg/ml and were by 2−3 orders of magnitude lower compared to established for surfactants synthesized in modified media # 1–3. In the case of treatment of abiotic materials with surfactant solutions obtained on the basal medium, the adhesion of bacteria and fungi was on average 10–20 % lower than after surface treatment by the surfactant synthesized in modified media. In the presence of 148−296 μg/ml of surfactants obtained in the basal medium, destruction of S. aureus BMS-1 and B. subtilis BT-2 biofilms was 45−66 %, and C. albicans D-6 yeast – 39−44 %. Under the action of similar concentrations of surfactants synthesized in modified media, the destruction of bacterial and yeast biofilms was lower: 6-52 and 20–46 %, respectively. Conclusions. The obtained results are consistent with the data of our previous studies on the possibility of regulating the antimicrobial and antiadhesive activity of surfactants in the process of producer cultivation by changing the content of cations in the medium, which are inhibitors/activators of enzymes responsible for the synthesis of components of the surfactants complex, which have certain biological properties.Документ Synergism of antimicrobial and anti-adhesive activity of Nocardia vaccinii IMV B-7405 surfactants in a mixture with essential oils(2020) Pirog, Tatiana; Kliuchka (Nykytyuk), Lilia; Kliuchka, Igor; Shevchuk, Tetiana; Iutynska, GalynaAn increase in the antibiotic resistance of pathogenic microorganisms has stimulated the search for alternatives to antibiotics substances of natural origin, which are essential oils (EO) and non-toxic biodegradable microbial surfactants. Aim. To investigate the antimicrobial and anti-adhesive activity of a mixture of EO and surfactants of Nocardia vaccinii IMV B-7405 synthesized on various oil-containing media. Methods. N. vaccinii IMV B-7405 was grown in medium containing as carbon source refined sunflower oil, oil after frying french fried potatoes, potato wedges and meat. The surfactants were extracted from supernatant of cultural liquid by modified Folch mixture. The antimicrobial action of tea tree, cinnamon and lemongrass EO, surfactants and their mixtures was determined by index of the minimum inhibitory concentration (MIC). Synergistic effect of surfactants and EO was evaluated by indicator of fractional inhibitory concentration. The degree of bacteria and fungi biofilms destruction under the action of surfactants, EO and their mixtures was determined by spectrophotometric method. Results. It was found that N. vaccinii IMV B-7405 surfactants synthesized on all oil-containing substrates showed a synergistic antimicrobial and anti-adhesive activity with the investigated EO. MIC of a surfactants and EO mixture against bacteria (Bacillus subtilis BT-2 (spores), Escherichia coli IEM-1, Staphylococcus aureus BMS-1) and yeast (Candida albicans D-6, Candida utilis BVS-65 and Candida tropicalis RE-2) were 2–20 μg/ml and were significantly lower than each compound separately (156–625 and 8–80 μg/ml for EO and surfactants, respectively). The destruction of bacterial and yeast biofilms under the action of a mixture of surfactants (20–40 μg/ml) and EO (20–40 μg/ml) was 1.3–2.9 times higher compared with using of each component separately at similar concentrations. Conclusions. The data presented the possibility of using a mixture of EO and surfactants not only to reduce their MIC, but also as effective antimicrobial and anti-adhesive agents.Документ Effect of tryptophane on synthesis of certain exometabolites by bacteria of genus Acinetobacter, Nocardia, and Rhodococcus and their properties(2022) Pirog, Tatiana; Piatetska, Daria; Zhdanyuk, Valentina; Leonova, Natalia; Shevchuk, TetianaThe efficiency of integrated microbial biotechnologies for obtaining several practically valuable metabolites in one technological process is determined both by the maximum concentration of these substances and their properties. This is especially true for secondary metabolites, the composition and properties of which vary depending on the cultivation conditions of the producer. Aim. To research the eff ect of tryptophan (a precursor of auxin biosynthesis) in the culture media on the synthesis of certain exometabolites by Rhodococcus erythropolis IMV Ac-5017, Acinetobacter calcoaceticus IMV B-7241, and Nocardia vaccinii IMV B-7405 as well as their properties. Methods. R. erythropolis IMV Ac-5017, A. calcoaceticus IMV B-724, and N. vaccinii IMV B-7405 were cultivated in a medium containing refi ned and waste sunflower oil, biodiesel waste, or ethanol as a carbon source. The concentration of tryptophan in the medium was 300 mg/L. Surfactants were extracted from the supernatant of the cultural liquid with a modified Folch mixture. Phytohormones were isolated from the supernatant by sequential extraction with organic solvents after surfactant extraction. Thin-layer chromatography was used for preliminary purification and concentration of phytohormones. Qualitative and quantitative determination of auxins was performed using high-performance liquid chromatography. The antimicrobial activity of surfactants was analysed by the minimum inhibitory concentration. The activity of enzymes of surface-active glycoand aminolipids biosynthesis (phosphoenolpyruvate synthetase, phosphoenolcarboxykinase, and NADP+-dependent glutamate dehydrogenase) was determined spectrophotometrically during the oxidation of NADH or NADP. Results. It was found that the presence of tryptophan in the culture medium of the strains under study did not affect the number of synthesized surfactants, which was 1.80−1.90, 1.55−1.75, and 1.50−1.65 g/L, respectively. At the same time, cultivation of R. erythropolis IMV Ac-5017, A. calcoaceticus IMV B-724, and N. vaccinii IMV B-7405 in the media with tryptophan increased the number of phytohormones: it was higher than the amount of phytohormones synthesized during cultivation without a precursor. The introduction of tryptophan into the culture medium of the strains was accompanied by the formation of surfactants. These compounds showed 2−4 times higher antimicrobial activity against the phytopathogenic bacteria (Agrobacterium tumefaciens UCM B-1000, Pseudomonas syringae UCM B-1027T, Xanthomonas vesicatoria UCM B-1106, Pectobacterium carotovorum UCM B-1075T, Clavibacter michiganensis IMV B-102 and Pseudomonas syringae pv. tomato IMV B-9167) than compounds synthesized on a medium without a precursor. The antimicrobial activity of surfactants synthesized by A. calcoaceticus IMV B-7241 in the presence of tryptophan either did not change compared to that for surfactants obtained without tryptophan, or increased slightly. Data on the activity of surfactant biosynthesis enzymes correlated with the indicators of their antimicrobial activity. In the presence of tryptophan in the culture medium of N. vaccinii IMV B-7405 and R. erythropolis IMV Ac-5017, NADP+-dependent glutamate dehydrogenase activity in the cells of these strains (a key enzyme for biosynthesis of aminolipids responsible for antimicrobial activity) increased almost by 1.4 times compared to that on a tryptophan-free medium. Conclusions. As a result of this work, it was found that the presence of tryptophan in the culture medium of researched strains did not affect the number of surfactants. The antimicrobial activity of surfactants against phytopathogenic bacteria either increased or remained unchanged compared to that established for surfactants synthesized without a precursor of auxin biosynthesis. The obtained data testify to the high efficiency of the potential use of surfactants complex preparations and phytohormones in crop production to stimulate the growth of plants and biocontrol of phytopathogenic bacteria.Документ Destruction of biofilms under the influence of Acinetobacter calcoaceticus IMV B-7241 surfactants, synthesized in the presence of competitive microorganisms(2022) Pirog, Tatiana; Ivanov, MykytaIntroduction. The aim of this study was to investigate the role of surfactants synthesized by Acinetobacter calcoaceticus IMV B-7241 in media with glycerol in the presence of biological inductors in destruction of biofilms. Materials and methods. Cultivation of A. calcoaceticus IMV B-7241 was carried out in a mineral medium using refined glycerol or crude glycerol, the waste of biodiesel production, as carbon sources. Biological inductors were introduced as live or inactivated cells of Bacillus subtilis BT-2, as well as the supernatant after strain BT-2 cultivation. Surfactants were extracted from the supernatant of the culture liquid with a modified mixture of Folch (chloroform and methanol, 2:1). The degree of biofilm destruction in the presence of surfactants was determined by spectrophotometric method. Results and discussion. Regardless of the substrate used, the introduction of both live and inactivated cells of B. subtilis BT-2 into medium used for cultivation of A. calcoaceticus IMV B-7241 was accompanied by the synthesis of surfactants, the degree of biofilm destruction of which was higher than those obtained in the medium without an inductor. The degree of destruction of bacterial and yeast biofilms achieved by the action of A. calcoaceticus IMV B-7241 surfactants obtained on refined glycerol in the presence of inductor cells was 36.5–85% and was 1.5-3 times higher compared to using surfactants synthesized in medium without inductors. Note that, surfactants synthesized in the presence of biological inductors destroyed biofilms of the test cultures at fairly low (7.5–960 μg/ml) concentrations. Similar results were observed for the usage of surfactants obtained on the waste of biodiesel production. Therefore, introduction of live cells of B. subtilis BT-2 into the medium with the crude glycerol was accompanied by synthesis of surfactants, which at concentration 1.8-960 μg/ml caused destruction of B. subtilis BT-2, Proteus vulgaris PA-12 and Enterobacter cloacae C-8 biofilms at 30.1–80.7% and was higher than using similar surfactant concentrations obtained during cultivation without inductors (24.1–75%). The destruction of biofilms of Staphylococcus aureus BMS-1, Candida albicans D-6 and Candida tropicalis PE-2 under the action of surfactants (1.8-960 μg/ml) synthesized on crude glycerol in the presence of both live or inactivated cells of B. subtilis BT-2 was 1.5–8 times higher than surfactants synthesized in medium without inductor. Conclusion. The possibility to regulate the ability to destroy bacterial and yeast biofilms of surfactants synthesized by A. calcoaceticus IMV B-7241 by introducing into the medium competitive bacteria B. subtilis BT-2 was found.Документ Antimicrobial activity of a mixture of surfactants produced by Acinetobacter calcoaceticus IMV B-7241 with antifungal drugs and essential oils(2022) Pirog, Tatiana; Kliuchka, Igor; Kliuchka (Nykytyuk), LiliaIntroduction. The aim of the work was to study the effect of a mixture of surfactants synthesized by Acinetobacter calcoaceticus IMV B-7241 under various cultivation conditions with antifungal drugs (clotrimazole and fluconazole) and essential oils (cinnamon and lemongrass) on yeast of genus Candida. Material and methods. The cultivation of A. calcoaceticus IMV B-7241 was carried out in a basic medium that did not contain NaCl (medium 1), contained NaCl, 2.0 g/l (medium 2), contained NaCl, 2.0 g/l, and KCl, 1.0 g/l (medium 3). The surfactants were extracted from supernatant of cultural liquid by modified Folch mixture. Antimicrobial properties of the surfactants, antifungal drugs and essential oils were determined by index of the minimum inhibitory concentration (MIC). To assess the synergistic effect of a mixture of surfactants with antifungal drugs or essential oils the fractional inhibitory concentration index was used. Results and discussion. Surfactants synthesized by A. calcoaceticus IMV B-7241 on the basic medium were the most effective antimicrobial agents against the yeasts strains Candida albicans D-6, C. tropicalis RE-2 and C. utilis BVS-65 with MIC 22.5–45 μg/ml that were 2.6–17 times lower than the values determined for surfactants synthesized on modified media. At the same time, regardless of the strain cultivation in different media, all surfactants showed synergism of antifungal activity with clotrimazole, fluconazole, cinnamon or lemongrass essential oils. Thus, in the presence of surfactants synthesized on basic and modified media in a mixture with antifungal drugs, MIC of clotrimazole and fluconazole against the studied yeast test cultures decreased by 4–32 times. The use of a mixture of essential oils with surfactants synthesized by A. calcoaceticus IMV B-7241 growing in different media made it possible to reduce MIC of cinnamon and lemongrass oils against yeasts of Candida genus 4–18 and 8–32 times, respectively. At the same time, the index of fractional inhibitory concentration did not exceed 0.5, which indicates the synergism of anifungal activity between the studied compounds. Conclusion. The results confirm the possibility to reduce the minimum inhibitory concentrations of antifungal drugs or essential oils against members of genus Candida by their mixture with microbial surfactants.Документ Regulation of biological activity of surfactants under cultivation of Acinetobacter calcoaceticus IMB B-7241 on glycerol(2021) Pirog, Tatiana; Lutsay, Dariya; Yarova, HannaIntroduction. The aim of this research was to study the biological activity of surfactants synthesized by Acinetobacter calcoaceticus IMV B-7241 in the medium with glycerol of various degrees of purification and high content of calcium cations (activators of NADH+-dependent glutamate dehydrogenase, which is a key enzyme of biosynthesis of surface-active aminolipids responsible for antimicrobial activity of surfactant complex). Materials and methods. Cultivation of A. calcoaceticus was carried out in liquid mineral medium using as substrates refined glycerol and the waste from biodiesel production. The base medium did not contain calcium chloride, the content of CaCl2 in the modified medium was 0.1 and 0.2 g/l. Surfactants were extracted from the supernatant of the culture luquid with a modified mixture of Folch. The number of adhered cells and the degree of biofilm destruction in the presence of surfactants was determined by spectrophotometric method, antimicrobial activity of surfactants - by the minimum inhibitory concentration (MIC). Results and discussion. It was found that the additional introduction of 0.1−0.2 g/l of CaCl2 into cultivation medium with refined glycerol was accompanied by the synthesis of surfactants, the MIC of which against bacteria (Bacillus subtilis BТ-2, Enterobacter cloacae C-8, Staphylococcus aureus BМS-1) and yeast (Candida albicans D-6) were 1.01–21.3 μg/ml and were 1.4–29 times lower compared to the MIC of surfactants obtained in base medium (1.83−58.8 μg/ml). The adhesion of test cultures on abiotic materials treated with such surfactants was 8–13% lower, and the degree of biofilms destruction was 5–19% higher compared to the values, established for surfactants obtained on base medium. The increasіng antimicrobial and anti-adhesive activity of surfactants synthesized on waste of biodiesel production was observed only when CaCl2 was introduced into the medium at a concentration of 0.2 g/l. Surfactants synthesized in the presence of calcium cations in the medium with the waste of biodiesel production proved to be more effective destructors of bacterial biofilms in comparison with those obtained in the base medium only at low concentrations (0.7–5.5 μg/ml). Conclusion. The results demonstrate the possibility of regulating the biological activity of A. calcoaceticus IMV B-7241 surfactants by changing in the composition of medium content of calcium cations - activators of NADH+-dependent glutamate dehydrogenase (key enzyme of surface-active aminolipids biosynthesis). Surfactants synthesized under different cultivation conditions of A. calcoaceticus IMB B-7241 on glycerol are more effective biofilm destructors and antimicrobial and anti-adhesive agents compared to the known lipopeptides and rhamnolipids formed on glycerol.Документ Post-harvest treatment of vegetables with exometabolites of Nocardia vaccinii IMV B-7405, Acinetobacter calcoaceticus IMV B-7241 and Rhodococcus erythropolis IMV Aс-5017 to extend their shelf life(2019) Pirog, Tatiana; Geichenko, Bogdana; Zvarych, AnnaThe aim of the work was to study the possibility of Nocardia vaccinii IMV B-7405, Acinetobacter calcoaceticus IMV B-7241 and Rhodococcus erythropolis IMV Ac-5017 supernatants usage with various concentrations of surfactants for post-harvest treatment of vegetables. N. vaccinii IMV B-7405, A. calcoaceticus IMV B-7241 and R. erythropolis IMV Ac-5017 were grown on waste sunflower oil and ethanol. For vegetables treatment, supernatants of the culture broth with surfactant concentration of 0.01–0.5 g/l were used. The concentration of surfactants was determined by the gravimetric method after extraction with Folch mixture. The total number of heterotrophic bacteria and fungi on the surface of vegetables was determined by the Koch method on meat-peptone agar and wort agar, respectively. It was shown that treatment of broccoli, Brussels sprouts, sweet pepper and tomatoes with N. vaccinii IMV B-7405, A. calcoaceticus IMV B-7241 and R. erythropolis IMV Ac-5017 supernatants was accompanied by 6–17 and 8–50 times decrease of bacteria and fungi number on their surface, respectively, compared with that on the surface of vegetables washed with tap water. The possibility of double use of the same supernatant for various batches of vegetables washing was established. Non-treated and water-washed vegetables rotted faster than those treated with surfactant-containing supernatants. N. vaccinii IMV B-7405, R. erythropolis IMV Ac-5017 and A. calcoaceticus IMV B-7241 exometabolites used for treating vegetables to extend their shelf life have the following advantages in comparison with known microbial surfactants: they exhibit high antimicrobial activity when the surfactant concentration was several times lower and in the form of supernatant, which lets you exclude the expensive stage of isolation and purification of the target product from the technological process. In addition, surfactant-containing supernatants are highly effective in their repeated use. Метою роботи було вивчити можливість використання супернатантів Nocardia vaccinii ІМВ В-7405, Acinetobacter calcoaceticus ІМВ В-7241 та Rhodococcus erythropolis ІМВ Ас-5017 з різними концентраціями ПАР для післязбиральної обробки овочів. N. vaccinii IMV B-7405, A. calcoaceticus IMV B-7241 та R. erythropolis IMV Ac-5017 вирощували на відпрацьованій соняшниковій олії та етанолі. Для обробки овочів використовували супернатанти культурального бульйону з концентрацією ПАР 0,01–0,5 г/л. Концентрацію ПАР визначали гравіметричним методом після екстракції сумішшю Фольха. Загальну кількість гетеротрофних бактерій та грибів на поверхні овочів визначали методом Коха на м’ясо-пептонному агарі та сусло-агарі відповідно. Показано, що обробка брокколі, брюссельської капусти, солодкого перцю та томатів супернатантами N. vaccinii IMV B-7405, A. calcoaceticus IMV B-7241 та R. erythropolis IMV Ac-5017 супроводжувалася 6–17 та 8–50 разів зменшується кількість бактерій і грибків на їх поверхні відповідно в порівнянні з такою на поверхні овочів, промитих водопровідною водою. Встановлено можливість дворазового використання одного і того ж супернатанту для різних партій миття овочів. Необроблені та промиті водою овочі гнили швидше, ніж ті, що були оброблені супернатантами, що містять ПАР. Екзометаболіти N. vaccinii IMV B-7405, R. erythropolis IMV Ac-5017 та A. calcoaceticus IMV B-7241, які використовуються для обробки овочів з метою подовження терміну їх зберігання, мають наступні переваги порівняно з відомими мікробними поверхнево-активними речовинами: вони виявляють високу антимікробну активність, коли концентрація ПАР була в рази нижчою і у вигляді супернатанту, що дозволяє виключити з технологічного процесу дорогий етап виділення та очищення цільового продукту. Крім того, супернатанти, що містять поверхнево-активні речовини, є високоефективними при багаторазовому застосуванні.