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Документ Ethapolan synthesis by Acinetobacter sp. IMV B-7005 on the mixture of С2-С6-substrates and waste sunflower oil(2021) Voronenko, Andryi; Pirog, TatianaThe cultivation conditions of Acinetobacter sp. IMV B-7005, which would provide maximum synthesis of the microbial exopolysaccharide (EPS) ethapolan on the mixture of C2-C6–substrates (molasses, acetate, or ethanol) and waste sunflower oil was studied.Документ Intensification of microbial exopolysaccharide ethapolan synthesis on the mixture of energy-excessive substrates(2021) Voronenko, Andryi; Pirog, TatianaIntroduction. The cultivation conditions of Acinetobacter sp. IMV B-7005, providing maximum synthesis of exopolysaccharide (EPS) ethapolan on the mixture of ethanol and sunflower oil were studied, as well as the possibility of replacing refined oil in the mixture with ethanol on a waste one was demonstrated. Materials and methods. Strain IMV B-7005 was grown in liquid mineral media, containing the mixture of ethanol and sunflower oil of various quality, as well as appropriate monosubstrates. The optimal molar ratio of the concentrations of substrates in the mixture was calculated theoretically according to Babel’s concept. The EPS concentration was determined gravimetrically after precipitation with isopropanol, the EPS-synthesizing ability – as the ratio of the EPS concentration to the concentration of biomass and expressed in g EPS/g biomass. Results and discussion. The highest rates of ethapolan synthesis were observed with the molar ratio of concentrations of ethanol and refined sunflower oil in the mixture of 1:0.056, as close as possible to the theoretically calculated (1:0.076), and the use of inoculum grown on ethanol. Further increasing of the concentrations of ethanol and oil led to a decrease in pH of the culture fluid to a suboptimal level for the EPS synthesis (4.5-4.8). To ensure the synthesis of ethapolan on a medium with high concentrations of ethanol (4%) and oil (1.2%) ammonium nitrate was replaced with an equimolar amount of nitrogen KNO3 (0.8 g/l), which is transported into cells by the symport with proton; fractional introduction of substrates in five equal portions during cultivation was carried out and was increased the concentration of Mg2+ cations, which are one of the activators of acetyl-CoA synthetase in Acinetobacter sp. IMV B-7005 affecting the enzymatic activity of systems responsible for the catabolism of fatty acids. Under such cultivation conditions, regardless of the type of used sunflower oil (refined or mixed waste) in the mixture with ethanol, the concentration of ethapolan reached 13.5-16.0 g/l, and EPS-synthesizing ability – 3.1-3.7 g EPS/g of biomass, which were respectively 3.2-3.8 and 1.6-1.9 times higher than before optimization. Conclusions. Based on determining the optimal molar ratio of monosubstrate concentrations in the mixture, modification of the medium composition (replacement of ammonium nitrate with potassium nitrate, increasing the content of magnesium cations, replacement of refined oil on a mixed waste one) and fractional addition of substrates the possibility of intensification of ethapolan synthesis on the mixture of energy-excessive substrates (ethanol and sunflower oil) was established.Документ Peculiarities of microbial exopolysaccharide ethapolan synthesis on mixed waste oils(2018) Ivahniuk, Mykola; Voronenko, Andryi; Pirog, TatianaPossibility of the microbial exopolysaccharide (EPS) ethapolan (the producer − Acinetobacter sp. IMB B-7005) synthesis intensification on the mixture of waste oils of various types and quality, as well as the emulsifying properties of that EPS, synthesized in such conditions, were studied. Materials and methods. Cultivation of Acinetobacter sp. IМV B-7005 strain was performed in liquid medium, containing as a carbon source waste oils (sunflower, corn, olive) at concentration 5%, v/v. EPS concentration was determined gravimetrically after precipitation with isopropanol, EPS-synthesizing ability − as a ratio of EPS concentration to biomass concentration, wich was expressed as g EPS / g biomass. Results and discussions. Regardless of the oil type in the inoculum obtaining medium (olive or sunflower), the ethapolan synthesis indexes on the mixture of waste sunflower and olive oils (in the ratio of 1:4; 4:1; 1:1) were slightly lower than in conditions of the producer growth on refined sunflower oil, but at the same time increasing of the EPS-synthesizing ability on 14−41% was observed. Using mixed after frying meat, potatoes, onions and cheese sunflower oil as a substrate for the ethapolan production accompanied by the synthesis of the same polysaccharide concentration, as well as on refined oil. Reduction of the initial quantity of mixed sunflower oil to 1.25−2% with followed fractional adding in portions of 1.25−1.5% in the cultivation process to the final amount of 5% was accompanied by increase of ethapolan concentration on 15−20% compared to a one-time addition of 5% substrate. Solutions of the synthesized under such conditions polysaccharide at concentration of 0.05% emulsified hexadecane, gasoline, diesel fuel (emulsification index 48−52%), and the formed emulsion was stable for 20 days. Conclusion. The results demonstrate the possibility of universal technology creating for microbial exopolysaccharide ethapolan production on mixed waste sunflower oil, regardless of the substrate type and supplier. Можливість інтенсифікації синтезу мікробного екзополісахариду (ЕПС) етаполана (продуцент − Acinetobacter sp. IMB B-7005) на суміші відпрацьованих масел різного типу та якості, а також емульгуючі властивості цього ЕПС, синтезованого в таких умовах, були вивчені. Матеріали та методи. Культивування Acinetobacter sp. Штам IМV B-7005 проводили на рідкому середовищі, що містить як джерело вуглецю відпрацьовані олії (соняшникова, кукурудзяна, оливкова) у концентрації 5 % об./об. Концентрацію ЕПС визначали гравіметрично після осадження ізопропанолом, ЕПС-синтезуючу здатність − як відношення концентрації ЕПС до концентрації біомаси, яке виражали як г ЕПС / г біомаси. Результати та обговорення. Незалежно від типу олії в середовищі отримання інокулята (оливкова чи соняшникова) показники синтезу етаполану на суміші відходів соняшникової та оливкової олій (у співвідношенні 1:4; 4:1; 1:1) були дещо нижчими, ніж в умовах зростання продуцента на рафінованій соняшниковій олії, але при цьому спостерігалося підвищення ЕПС-синтезуючої здатності на 14−41%. Використання змішаної після смаження м’яса, картоплі, цибулі та сиру соняшникової олії як субстрат для виробництва етаполану, що супроводжується синтезом полісахаридів такої ж концентрації, як і на рафінованій олії. Зменшення вихідної кількості суміші соняшникової олії до 1,25−2 % з наступним дробовим додаванням порціями 1,25−1,5 % у процесі культивації до кінцевої кількості 5 % супроводжувалося підвищенням концентрації етаполану на 15−20 % порівняно з одноразове додавання 5% субстрату. Розчини синтезованого в таких умовах полісахариду концентрацією 0,05 % емульгували гексадекан, бензин, дизельне паливо (індекс емульгування 48−52 %), і утворена емульсія була стабільною протягом 20 діб. Висновок. Результати демонструють можливість створення універсальної технології виробництва мікробного екзополісахариду етаполану на змішаних відходах соняшникової олії незалежно від типу субстрату та постачальника.Документ Non-traditional producers of microbial exopolysaccharides(2018) Pirog, Tatiana; Voronenko, Andryi; Ivahniuk, MykolaData on exopolysaccharides synthesis by psychrophilic fungi and bacteriae, halo- and thermophilic archaea and bacteriae, including those isolated from deep-sea hydrothermal vents − sources − were provided. Physiologic significance, physico-chemical properties and possible practical applications of exopolysaccharides from unusual sources were analyzed. Most of them have immunomodulating, antiviral, anticoagulant, antitumor, antioxidant activities promising for medical and pharmaceutical applications. Meanwhile, based on the literature date, the conclusion follows about the urgent necessity to develop efficient technologies for synthesis of these exopolysaccharides by nontraditional producers, which currently lags far behind common techniques. Наведено дані про синтез екзополісахаридів психрофільними грибами та бактеріями, гало- та термофільними археями та бактеріями, у тому числі виділеними з глибоководних гідротерм – джерел. Було проаналізовано фізіологічне значення, фізико-хімічні властивості та можливі практичні застосування екзополісахаридів з незвичайних джерел. Більшість із них мають імуномодулюючу, противірусну, антикоагулянтну, протипухлинну, антиоксидантну активність, перспективну для застосування в медицині та фармацевтиці. Водночас, виходячи з літературних даних, випливає висновок про нагальну необхідність розробки ефективних технологій синтезу цих екзополісахаридів нетрадиційними продуцентами, які на сьогодні значно відстають від загальноприйнятих.Документ Exopolysaccharides synthesis on industrial waste(2016) Pirog, Tatiana; Ivahniuk, Mykola; Voronenko, AndryiData from the literature and our own studies on the synthesis of microbial exopolysaccharides on various industrial waste (food industry, agricultural sector, biodiesel production, etc.) are reviewed here. Utilization of industrial waste to obtain exopolysaccharides will solve not only the problem of secondary raw materials accumulation, but also will reduce the costs of the biosynthesis of practically valuable metabolites. In addition, some kinds of waste have a number of advantages compared to traditional carbohydrate substrates: aside from environmental health benefits, there are technological ones, like the presence of growth factors. There is also no need to use anti-foam substances and substrate sterilization in the latter case.Документ Effect of environmental factors on the synthesis and properties of Acinetobacter sp. exopolysaccharides(1998) Pirog, Tatiana; Grinberg, Tamara; Malashenko, YuriEffects of external factors on the synthesis and physicochemical properties of Acinetobacter sp. exopolysaccharides (EPSs), which determine the biological functions of this microorganism, were studied. The cultivation temperature, medium pH, and oxygen concentration in the medium (p02) affected the viscosity of EPS solutions in the presence of monovalent cations, in the H+-form, and in a Cu2+-glycine system. All the EPSs studied were precipitated with heavy metal ions (Cr3+, Cu2+, Pb2+, Cd2+, etc.). No changes in the EPS yield were observed under unfavorable environmental conditions. At high pO2 values (up to 80% of saturation), the maximum specific rates of bacterial growth and EPS synthesis increased. It was suggested that Acinetobacter sp. EPSs perform different biological functions under optimal and nonoptimal conditions.Документ Ethapolan: a new microbial exopolysaccharide for oil industry(1995) Grinberg, Tamara; Pirog, Tatiana; Malashenko, Yuri; Vlasov, Sergei A.Ethapolan, a new high-viscous exopolysaccharide, was obtained in the course of microbial synthesis. Its chemical content and some characteristics of its solutions are explored in the present study. By its structure ethapolan may be considered a polysaccharide of xanthan type. More definitely, as compared to xanthan, the emulsifying efficiency and hydrophobic nature of ethapolan may be attributed to the presence of the fatty acids residues and to 6-desoxysaccharide—rhamnose residues. It was found that a few factors impact the increasing viscosity of ethapolan solutions: first, the presence of the cations; second, low shearing rates; and, finally, low pH values. Ethapolan is resistant to heating. On this basis, it may be concluded that ethapolan appears to be a universal and quite competitive microbial exopolysaccharide for the oil industry.Документ The influence of culture conditions on the physico-chemical properties of exopolysaccharide etapolana(2009) Pirog, Tatiana; Korzh, Yuliya; Shevchuk, TetianaThe physicochemical properties of the complex exopolysaccharide ethapolan (EPS) produced by Acinetobacter sp. 12S during growth on media with various C/N ratios and different concentrations of mineral components and phosphate buffer were studied. Irrespective of the cultivation conditions, the concentrations of carbohydrates (38–44%) and pyruvic acid (3.2–3.7%) in the total EPS, as well as in the acylated (AP) and nonacylated (NAP) polysaccharides obtained from them, were practically the same. The EPS, AP, and NAP were also identical in their monosaccharide composition: the molar ratio of glucose, mannose, galactose, and rhamnose was 3 : 2 : 1 : 1. The polysaccharides contained different concentrations of mineral salts (6–28%), uronic acid (3.7–22.0%), and fatty acids (5.8–15.4%); they also differed in the ratio of acetylated and nonacetylated polysaccharides. Due to the differences in the chemical composition and molecular mass (500 kDa – 1.5 MDa), the viscosities of the EPS solutions (in the presence of 0.1 M KCl, in the H+–form, and in Cu2+–glycine system) were different as well. The mechanisms responsible for changes in the physicochemical properties of the total EPS, AP, and NAP synthesized on various media are discussed.Документ Formation of the Exopolysaccharide ethapolan by acinetobacter sp. IMV B-7005 on a fumarate–glucose mixture(2007) Pirog, Tatiana; Vysyatetska, Nadezhda; Korzh, YuliyaOur studies enabled us to intensify the synthesis of the microbial exopolysaccharide (EPS) ethapolan produced by Acinetobacter sp. IMV B-7005 grown on a mixture of fumarate (an energy-excessive substrate) and glucose (an energy-deficient substrate). Supplementing glucose-containing medium with sodium (potassium) fumarate at a molar ratio of 4 : 1 resulted in a 1.3–2.2-fold increase of the EPS amount synthesized and in a 1.3–2-fold increase of the EPS yield relative to the biomass compared to cultivation on monosubstrates. The conversion of the carbon of both substrates to EPS was the highest if the carbon/nitrogen ratio in the cultivation medium was 70.5 and inoculum grown on glucose monosubstrate was used.Документ Exopolysaccharide Production and Peculiarities of C6-Metabolism in Acinetobacter sp. Grown on Carbohydrate Substrates(2002) Pirog, Tatiana; Kovalenko, M.; Kuzminska, Yu.An Acinetobacter sp. strain grown on carbohydrate substrates (mono- and disaccharides, molasses, starch) was shown to synthesize exopolysaccharides (EPS). Glucose catabolism proved to proceed via the Embden–Meyerhof–Parnas and Entner–Doudoroff pathways. Pyruvate entered the tricarboxylic acid cycle due to pyruvate dehydrogenase activity. Pyruvate carboxylation by pyruvate carboxylase was the anaplerotic reaction providing for the synthesis of intermediates for the constructive metabolism of Acinetobacter sp. grown on C6-substrates. The C6-metabolism in Acinetobacter sp. was limited by coenzyme A. Irrespective of the carbohydrate growth substrate (glucose, ethanol), the activities of the key enzymes of both C2- and C6-metabolism was high, except for the isocitrate lyase activity in glucose-grown bacteria. Isocitrate lyase activity was induced by C2-compounds (ethanol or acetate). After their addition to glucose-containing medium, both substrates were utilized simultaneously, and an increase was observed in the EPS synthesis, as well as in the EPS yield relative to biomass. The mechanisms responsible for enhancing the EPS synthesis in Acinetobacter sp. grown on a mixture of C2- and C6-substrates are discussed.