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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 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.