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1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vladimirova A. V., Murueva A. V., Shershneva A. M., Prudnikova S. V., Shabanov A. V., Shishatskaya E. I.
Заглавие : Biocompatible systems for controlled delivery of antiseptics for topical application
Колич.характеристики :14 с
Место публикации : J. Sib. Fed. Univ. Biol. - 2024. - Vol. 17, Is. 1. - P.19-32. - ISSN 19971389 (ISSN); Журн. СФУ. Биол. - ISSN 23135530 (eISSN)
Примечания : Cited References: 28
Аннотация: Controlled drug delivery is one of the frontier areas of science, which uses an interdisciplinary approach. The delivery systems offer numerous advantages over conventional dosage forms, such as improved efficacy and patient compatibility, reduced toxicity, and ease of use. Such systems often use micro- and nanoparticles as carriers for drugs, the prolonged effect of which is achieved due to the controlled slow release of the encapsulated drug. This study investigated the effects of encapsulation of various antiseptics (brilliant green, miramistin, and furacilin) and the chemical composition of the polymer on the yield, structure, size, drug release kinetics, and antibacterial activity of microparticles produced from resorbable polyesters of microbiological origin, polyhydroxyalkanoates. Microparticles with a 5.6–94.8 μm diameter were produced. The form of the active substance molecule has been found to be the most significant factor affecting the characteristics of polyhydroxyalkanoate microparticles. The surface structure of particles is rather determined by the chemical composition of the polymer, and the release kinetics to the model medium depends on the encapsulated drug. Microparticles based on PHAs loaded with brilliant green and furacilin showed antibacterial effects in S. aureus and E. coli cultures. The study demonstrated that microparticles with antiseptics encapsulated in them have potential as prolonged drug delivery systems and are of interest for further research.Технология контролируемой доставки лекарств является одной из передовых областей науки, включающей междисциплинарный научный подход. Эти системы доставки обладают многочисленными преимуществами по сравнению с обычными лекарственными формами, такими как повышенная эффективность и биосовместимость, сниженная токсичность и простота использования. В таких системах в качестве носителей лекарственных средств часто используют микро- и наночастицы, пролонгированное действие которых достигается за счет контролируемого медленного высвобождения инкапсулированного лекарственного средства. В данном исследовании изучалось влияние включения различных антисептиков (бриллиантовый зелёный, мирамистин и фурацилин), а также химического состава полимера на выход, структуру, размер, кинетику высвобождения лекарственных средств и антибактериальную активность микрочастиц, полученных из резорбируемых полиэфиров микробиологического происхождения, полигидроксиалканоатов. Было получено семейство микрочастиц диаметром 5,6–94,8 мкм. Установлено, что наиболее значимым фактором, влияющим на характеристики микрочастиц полигидроксиалканоатов, является форма молекулы активного вещества. Структура поверхности частиц больше зависит от химического состава полимера, а кинетики выхода в модельную среду – от инкапсулированного лекарства. Микрочастицы на основе ПГА с депонированными бриллиантовым зеленым и фурацилином показали антибактериальное действие в культурах S. aureus и E. coli. Результаты продемонстрировали, что микрочастицы с депонированными антисептиками обладают потенциалом в качестве систем пролонгированной доставки и представляют интерес для дальнейших исследований.
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2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova, Tatiana G., Demidenko, Aleksey V., Murueva, Anastasiya V., Dudaev, Alexey E., Nemtsev I. V., Shishatskaya, Ekaterina I.
Заглавие : Biodegradable polyhydroxyalkanoates formed by 3- and 4-hydroxybutyrate monomers to produce nanomembranes suitable for drug delivery and cell culture
Колич.характеристики :23 с
Место публикации : Technologies. - 2023. - Vol. 11, Is. 4. - Ст.106. - ISSN 22277080 (eISSN), DOI 10.3390/technologies11040106
Примечания : Cited References: 116. - his research was funded by State Assignment of the Ministry of Science and Higher Education of the Russian Federation (project No. 0287-2021-0025)
Аннотация: Biodegradable polyhydroxyalkanoates, biopolymers of microbiological origin, formed by 3- and 4-hydroxybutyrate monomers P(3HB-co-4HB), were used to obtain nanomembranes loaded with drugs as cell carriers by electrospinning. Resorbable non-woven membranes from P(3HB-co-4HB) loaded with ceftazidime, doripinem, and actovegin have been obtained. The loading of membranes with drugs differently affected the size of fibers and the structure of membranes, and in all cases increased the hydrophilicity of the surface. The release of drugs in vitro was gradual, which corresponded to the Higuchi and Korsmeyer-Peppas models. Antibiotic-loaded membranes showed antibacterial activity against S. aureus and E. coli, in which growth inhibition zones were 41.7 ± 1.1 and 38.6 ± 1.7 mm for ceftazidime and doripinem, respectively. The study of the biological activity of membranes in the NIH 3T3 mouse fibroblast culture based on the results of DAPI and FITC staining of cells, as well as the MTT test, did not reveal a negative effect despite the presence of antibiotics in them. Samples containing actovegin exhibit a stimulating effect on fibroblasts. Biodegradable polyhydroxyalkanoates formed by 3-hydroxybutyrate and 4-hydroxybutyrate monomers provide electrospinning non-woven membranes suitable for long-term delivery of drugs and cultivation of eukaryotic cells, and are promising for the treatment of wound defects complicated by infection.
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3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova, Tatiana G., Zhila, Natalia O., Kiselev, Evgeniy G., Sukovatyi, Aleksey G., Lukyanenko A. V., Shishatskaya, Ekaterina I.
Заглавие : Biodegradable polyhydroxyalkanoates with a different set of valerate monomers: Chemical structure and physicochemical properties
Колич.характеристики :21 с
Место публикации : Int. J. Mol. Sci. - 2023. - Vol. 24, Is. 18. - Ст.14082. - ISSN 16616596 (ISSN), DOI 10.3390/ijms241814082. - ISSN 14220067 (eISSN)
Примечания : Cited References: 99. - The study was funded by the Russian Science Foundation (project no. 23-64-10007)
Аннотация: The properties, features of thermal behavior and crystallization of copolymers containing various types of valerate monomers were studied depending on the set and ratio of monomers. We synthesized and studied the properties of three-component copolymers containing unusual monomers 4-hydroxyvalerate (4HV) and 3-hydroxy-4-methylvalerate (3H4MV), in addition to the usual 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV) monomers. The results showed that P(3HB-co-3HV-co-4HV) and P(3HB-co-3HV-co-3H4MV) terpolymers tended to increase thermal stability, especially for methylated samples, including an increase in the gap between melting point (Tmelt) and thermal degradation temperature (Tdegr), an increase in the melting point and glass transition temperature, as well as a lower degree of crystallinity (40–46%) compared with P(3HB-co-3HV) (58–66%). The copolymer crystallization kinetics depended on the set and ratio of monomers. For terpolymers during exothermic crystallization, higher rates of spherulite formation (Gmax) were registered, reaching, depending on the ratio of monomers, 1.6–2.0 µm/min, which was several times higher than the Gmax index (0.52 µm/min) for the P(3HB-co-3HV) copolymer. The revealed differences in the thermal properties and crystallization kinetics of terpolymers indicate that they are promising polymers for processing into high quality products from melts.
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4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Boyandin A. N., Prudnikova S. V., Filipenko M. L., Khrapov E. A., Vasil'ev A. D., Volova T. G.
Заглавие : Biodegradation of polyhydroxyalkanoates by soil microbial communities of different structures and detection of PHA degrading microorganisms
Место публикации : Appl. Biochem. Microbiol.: MAIK Nauka-Interperiodica / Springer, 2012. - Vol. 48, Is. 1. - P.28-36. - ISSN 0003-6838, DOI 10.1134/S0003683812010024
Примечания : Cited References: 39. - The work was supported by the project initiated by the Government of the Russian Federation for governmental support of scientific research conducted under the guidance of leading scientists at Russian institutions of higher learning (Agreement No. 11.G34.31.0013) and the Program of Integrated Research of the Presidium of the Siberian Branch of Russian Academy of Sciences (project no. 96).
Предметные рубрики: POLY-BETA-HYDROXYBUTYRATE
CHAIN-LENGTH POLYHYDROXYALKANOATES
DEGRADATION
FILMS
POLY(3-HYDROXYBUTYRATE-CO-3-HYDROXYVALERATE)
BACTERIA
ACID
Аннотация: Biodegradation of microbial linear polymers of hydroxyalkanoic acids (polyhydroxyalkanoates, PHAs) by soil microbial communities of different structures has been studied during two field seasons in different weather conditions. This process was shown to be influenced by the polymer chemical composition, temperature, humidity, and the microbial soil component. The PHA degradation was accompanied by a decrease in the polymer molecular weight and an increase in the degree of crystallinity, indicating the preferential destruction of the amorphous phase compared to the crystalline one. The quantity of the true PHA destructors developing at the surface of the polymer samples was lower than the quantity of accompanying bacteria. The dominant PHA degrading microorganisms under the test conditions were identified as bacteria of the genera Variovorax, Stenotrophomonas, Acinetobacter, Pseudomonas, Bacillus, and Xanthomonas and as micromycetes from Penicillium, Paecilomyces, Acremonium, Verticillium, and Zygosporium.
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5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T., Menshikova O., Zhila N., Vasiliev A. D., Kiselev E., Peterson I., Shishatskaya E., Thomas S.
Заглавие : Biosynthesis and properties of P(3HB-co-3HV-co-3H4MV) produced by using the wild-type strain Cupriavidus eutrophus B-10646
Место публикации : J. Chem. Technol. Biotechnol. - 2019. - Vol. 94, Is. 1. - P.195-203. - ISSN 02682575 (ISSN) , DOI 10.1002/jctb.5763
Примечания : Cited References: 32. - This study was supported financially by Project ‘Agropreparations of the new generation: a strategy of construction and realization’ (Agreement No 074‐02‐2018‐328) in accordance with Resolution No 220 of the Government of the Russian Federation of April 9, 2010, ‘On measures designed to attract leading scientists to the Russian institutions of higher learning’.
Ключевые слова (''Своб.индексиров.''): polyhydroxyalkanoates--3-hydroxy-4-methylvalerate--synthesis--physicochemical properties
Аннотация: BACKGROUND: Polyhydroxyalkanoates (PHA) containing 3-hydroxy-4-methylvalerate (3H4MV) have better processing properties than other PHA types and were not prone to ageing. The main challenge in the production of these polymers is to simultaneously achieve high cell biomass, high polymer content, and high molar fraction of 3H4MV. The aim of this study was to investigate the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-3-hydroxy-4-methylvalerate) [P(3HB-co-3 HV-co-3H4MV)] by Cupriavidus eutrophus B-10646, synthesize polymers with different contents of 3H4MV and investigate their properties. RESULTS: It was shown that 4-methylvalerate (4MV, the precursor substrate) concentration in the culture medium must not be higher than 1 g L−1, and that 4MV must be carefully dosed, with at least 10–12 h intervals between supplementations. A series of polymers with molar fractions of 3H4MV between 2.7 and 11.3 mol% was synthesized. Degrees of crystallinity, molecular weight characteristics, and thermal properties of the polymers have been investigated as dependent on proportions of monomers. CONCLUSION: The content of 3H4MV depends on the concentration of 4MV and conditions of carbon nutrition. The molar fraction of 3H4MV had a strong effect on the crystalline to amorphous region ratio. PHA containing 3H4MV specimens synthesized in this study had a degree of crystallinity of below 50%, which remained unchanged for 2.5 years.
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6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zhila, Natalia O., Sapozhnikova, Kristina Yu., Berezovskaya, Arina V., Kiselev, Evgeniy G., Shishatskaya, Ekaterina I., Vasiliev A. D., Thomas, Sabu, Volova, Tatiana G.
Заглавие : Biosynthesis and properties of sulfur-containing polyhydroxyalkanoates (PHAs) produced by wild-type strain Cupriavidus necator B-10646
Место публикации : Polymers. - 2023. - Vol. 15, Is. 4. - Ст.1005. - ISSN 20734360 (eISSN), DOI 10.3390/polym15041005
Примечания : Cited References: 53. - The study was funded by State Assignment of the Ministry of Science and Higher Education of the Russian Federation (project No. 0287-2021-0025)
Аннотация: The study addresses the growth of the wild-type strain Cupriavidus necator B-10646 and the synthesis of sulfur-containing polyhydroxyalkanoates (PHA) by this strain on media containing fructose and three different precursors (3-mercaptopropionic acid, 3′,3′-dithiodipropionic acid and 3′,3′-thiodipropionic acid). By varying the concentration and number of doses of the precursors added into the bacterial culture, it was possible to find conditions that ensure the formation of 3-mercaptopropionate (3MP) monomers from the precursors and their incorporation into the C-chain of poly(3-hydroxybutyrate). A series of P(3HB-co-3MP) copolymer samples with different content of 3MP monomers (from 2.04 to 39.0 mol.%) were synthesized and the physicochemical properties were studied. The effect of 3MP monomers is manifested in a certain decrease in the molecular weight of the samples and an increase in polydispersity. Temperature changes are manifested in the appearance of two peaks in the melting region with different intervals regardless of the 3MP content. The studied P(3HB-co-3MP) samples, regardless of the content of 3MP monomers, are characterized by equalization of the ratio of the amorphous and crystalline phases and have a close degree of crystallinity with a minimum of 42%, = and a maximum of 54%.
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7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T. G., Kiselev E. G., Shishatskaya E. I., Zhila N. O., Boyandin A. N., Syrvacheva D. A., Vinogradova O. N., Kalacheva G. S., Vasiliev A. D., Peterson I. V.
Заглавие : Cell growth and accumulation of polyhydroxyalkanoates from CO2 and H2 of a hydrogen-oxidizing bacterium, Cupriavidus eutrophus B-10646
Место публикации : Bioresource Technol. - 2013. - Vol. 146. - P.215-222. - ISSN 0960-8524, DOI 10.1016/j.biortech.2013.07.070
Ключевые слова (''Своб.индексиров.''): autotrophic synthesis--cupriavidus eutrophus--polyhydroxyalkanoates
Аннотация: Synthesis of polyhydroxyalkanoates (PHAs) by a new strain of Cupriavidus - Cupriavidus eutrophus B-10646 - was investigated under autotrophic growth conditions. Under chemostat, at the specific flow rate D=0.1h-1, on sole carbon substrate (CO2), with nitrogen, sulfur, phosphorus, potassium, and manganese used as growth limiting elements, the highest poly(3-hydroxybutyrate) [P(3HB)] yields were obtained under nitrogen deficiency. In batch autotrophic culture, in the fermenter with oxygen mass transfer coefficient 0.460h-1, P(3HB) yields reached 85% of dry cell weight (DCW) and DCW reached 50g/l. Concentrations of supplementary PHA precursor substrates (valerate, hexanoate, ?-butyrolactone) and culture conditions were varied to produce, for the first time under autotrophic growth conditions, PHA ter- and tetra-polymers with widely varying major fractions of 3-hydroxybutyrate, 4-hydroxybutyrate, 3-hydroxyvalerate, and 3-hydroxyhexanoate monomer units. Investigation of the high-purity PHA specimens showed significant differences in their physicochemical and physicomechanical properties. В© 2013 Elsevier Ltd.
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8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Boyandin A. N., Sukhanova, Anna Alekseevna, Nikolaeva, Elena Dmitrievna, Nemtsev I. V.
Заглавие : Chemical modification of films from biosynthetic poly-3-hydroxybutyrate aimed to improvement of their surface properties
Коллективы : International Conference on Progress on Polymers and Composites , Ministry of Science and Higher Education of the Russian Federation [FEFE-2020-0015]
Место публикации : International Conference on Progress on Polymers and Composites (4th ; 26-28 Nov. 2020). Macromolecular Symposia. - 2021. - Vol. 395: 4th International Conference on Progress on Polymers and Composites (NOV 26-28, 2020, Electr. Network), Is. 1. - Ст.2000281. - ISSN 1022-1360, DOI 10.1002/masy.202000281. - ISSN 1521-3900(eISSN)
Примечания : Cited References: 11. - This work was carried out by the team of the scientific laboratory "Smart Materials and Structures" within the state assignment of the Ministry of Science and Higher Education of the Russian Federation for the implementation of the project "Development of multifunctional smart materials and structures based on modified polymer composite materials capable to function in extreme conditions" (No. FEFE-2020-0015). The surface of the samples was investigated using a scanning electron microscope Hitachi TM3000 in the Krasnoyarsk Regional Center of Research Equipment of Federal Research Center "Krasnoyarsk Science Center SB RAS"
Аннотация: Films from biodegradable poly-3-hydroxybutyrate are treated with chemical reagents to improve their hydrophilicity and biocompatibility. Two approaches are tested: a single treatment with alkali, acids, oxidizing or reducing agents, and a step-by step treatment of the alkali pre-activated surface of polymer films with bromine water and amino-compounds (ammonia or triethylamine). The maximal level of hydrophilicity (the lowest water contact angle and the highest polar component of the surface free energy) is registered after a single treatment with NaOH and after the step-by-step treatment. These samples also showed the best adhesion of mouse fibroblasts of NIH 3T3 line on the film surface. So, the proposed methods can be used to enhance hydropilicity and biocompatibility of biopolymer surface.
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9.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T., Kiselev E., Nemtsev I. V., Lukyanenko A. V., Sukovatyi A., Kuzmin A., Ryltseva G., Shishatskaya E.
Заглавие : Corrigendum to "Properties of degradable polyhydroxyalkanoates with different monomer compositions" International Journal of Biological Macromolecules; Volume 182, Pages 98–114
Колич.характеристики :3 с
Место публикации : Int. J. Biol. Macromol. - 2024. - Vol. 263, Pt. 1. - Ст.130252. - ISSN 01418130 (ISSN), DOI 10.1016/j.ijbiomac.2024.130252. - ISSN 18790003 (eISSN)
Примечания : Cited References: 1
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T., Goncharov D., Sukovatyi A. G., Shabanov A. V., Nikolaeva E., Shishatskaya E.
Заглавие : Electrospinning of polyhydroxyalkanoate fibrous scaffolds: effects on electrospinning parameters on structure and properties
Коллективы : Project 'Biotechnologies of novel biomaterials: innovative biopolymers and devices for biomedicine' [1, 11.G34.31.0013]; Government of the Russian Federation [220]; RF President for supporting young Doctors of Sciences [MD-3112.2012.4]
Место публикации : J. Biomater. Sci.-Polym. Ed.: Taylor & Francis, 2014. - Vol. 25, Is. 4. - P.370-393. - ISSN 0920-5063, DOI 10.1080/09205063.2013.862400. - ISSN 1568-5624
Примечания : Cited References: 52. - This study was financially supported by Project 'Biotechnologies of novel biomaterials: innovative biopolymers and devices for biomedicine' (Agreement No. 1 of 15.02.2013 to Agreement No. 11.G34.31.0013) in accordance with Resolution No. 220 of the Government of the Russian Federation of April 9, 2010, 'On measures designed to attract leading scientists to the Russian institutions of higher learning' and Grant of the RF President for supporting young Doctors of Sciences No. MD-3112.2012.4.
Предметные рубрики: TISSUE ENGINEERING APPLICATIONS
FIBER MATS
POLY 3-HYDROXYBUTYRATE
POLY(3-HYDROXYBUTYRATE-CO-3-HYDROXYVALERATE)
BIOCOMPATIBILITY
PROLIFERATION
FABRICATION
NANOFIBERS
COPOLYMERS
MEMBRANES
Ключевые слова (''Своб.индексиров.''): electrospinning--polyhydroxyalkanoates--ultrafine fibers--physical-mechanical properties--fibroblast cells
Аннотация: IIn this study, electrospinning was used to prepare ultrafine fibers from PHAs with different chemical compositions: P(3HB) and copolymers: P(3HB-co-4HB), P(3HB-co-3HV), and P(3HB-co-3HHx). The main process parameters that influence ultrafine fiber diameter and properties (polymer concentration, solution feeding rate, working distance, and applied voltage) have been investigated and their effects evaluated. The study revealed electrospinning parameters for the production of high-quality ultrafine fibers and determined which parameters should be varied to tailor the properties of the products. This study is the first to compare biological and physical-mechanical parameters of PHAs with different chemical compositions as dependent upon the fractions of monomers constituting the polymers and ultrafine fiber orientation. Mechanical strength of aligned ultrafine fibers prepared from different PHAs is higher than that of randomly oriented ones; no significant effect of ultrafine fiber orientation on surface properties has been found. None of the fibrous scaffolds produced by electrospinning from PHAs had any adverse effects on attachment, growth, and viability of NIH 3T3 mouse fibroblast cells, and all of them were found to be suitable for tissue engineering applications.
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11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T. G., Shishatskaya E. I., Zhila N. O., Киселев, Евгений Геннадьевич, Mironov P. V., Vasil'ev A. D., Peterson I. V., Sinskey A. J.
Заглавие : Fundamental basis of production and application of biodegradable polyhydroxyalkanoates
Место публикации : J. Sib. Fed. Univ. Biol. - 2012. - Vol. 5, Is. 3. - P.280-299; Журн. СФУ. Сер. "биология"
Ключевые слова (''Своб.индексиров.''): biopolymers--polyhydroxyalkanoates--substrates--synthesis--properties--processing--biomedical applications--биополимеры--полигидроксиалканоаты--субстраты--синтез--свойства--обработка--медико-биологическое применение
Аннотация: Microbial polyhydroxyalkanoates (PHAs) have long been studied due to their potential for replacement of petroleum-based plastic. The study addresses the effect of different conditions of carbon nutrition on synthesis of polyhydroxyalkanoates by the bacterium Ralstonia eutropha. First and foremost, PHAs are carbon storage compounds for many organisms. There are still many aspects of the physiology of PHA accumulation and degradation that are still not understood. Measurements of key P3HBrelated enzyme activities throughout cell growth reveal correlations of acetoacetyl-CoA reductase and synthase enzyme activity maxima with P3HB biosynthesis. The investigation addressed kinetic parameters of growth and accumulation of polyhydroxyalkanoates and gas exchange parameters of the culture of the CO-resistant strain of the hydrogen bacteria Ralstonia eutropha B 5786 cultivated on synthesis gas - a product of gasification of brown coals. The results were compared with those obtained by growing the bacteria on electrolytic hydrogen and it was concluded that synthesis gas can be successfully used to produce PHAs. In experiments with wild-type strain it has been first found that under mixotrophic growth conditions - CO2 + co-substrate (alcanoic acids) - bacteria can synthesize multi-component PHAs, consisting of short- and medium-chain-length monomers with carbon chains containing 4 to 8 atoms. It has been shown that PHA composition is determined by the type of the co-substrate. Fatty acids with odd number of carbons induce bacteria to synthesize multi-component PHAs with 3-hydroxybutyrate, 3-hydroxyvalerate, and 3-hydroxyhexanoate as major monomers and 3-hydroxyheptanoate and 3-hydroxyoctanoate as minor, occasionally occurring, ones. Fatty acids with even number of carbons induce synthesis of not only their respective monomers (3-hydroxyhexanoate and 3-hydroxyoctanoate) but also 3-hydroxyvalerate, making possible synthesis of four-component PHAs, containing 3-hydroxybutyrate and 3-hydroxyhexanoate as major components. A family of short- and medium-chain-length four- and five-component PHAs has been synthesized and their physicochemical and biomedical-properties examined.Полигидроксиалканоаты (ПГА) - перспективные материалы, которые могут заменить пластмассы на углеводородной основе, и они исследуются уже в течение длительного времени. Данная работа рассматривает воздействие различных условий углеродного питания на синтез полигидроксиалканоатов бактериями Ralstonia eutropha. Прежде всего ПГА являются запасными веществами для многих организмов. Многие аспекты физиологии накопления и разрушения ПГА остаются пока не изученными. Измерение активности ключевых ферментов 3ПГБ на протяжении роста клетки показывает связь максимумов активности ацетоацетил-КоА редуктазы и синтазы с биосинтезом 3ПГБ. Были исследованы кинетические параметры роста и накопления полигидроксиалканоатов и параметры газообмена культуры штамма водородных бактерий Ralstonia eutropha B 5786, устойчивого к СО, при культивировании на синтез-газе - продукте газификации бурых углей. Проведено сравнение полученных результатов с данными, полученными при выращивании бактерий на электролитическом водороде, и показано, что синтез-газ может успешно применяться для получения ПГА. В экспериментах с природным штаммом бактерий впервые было показано, что при миксотрофных условиях роста - CO2 + дополнительный субстрат (алкановые кислоты) - бактерии способны синтезировать многокомпонентные ПГА, состоящие из коротко- и среднецепочечных мономеров с длиной цепи от 4 до 8 атомов углерода. Показано, что состав ПГА зависит от типа дополнительного субстрата. Жирные кислоты с нечётным количеством атомов углерода стимулируют бактерии синтезировать многокомпонентные ПГА, состоящие из таких основных компонентов, как 3-гидроксибутират, 3-гидроксивалерат и 3-гидроксигексаноат, и второстепенных, эпизодических компонентов: 3-гидроксигептаноата и 3-гидроксиоктаноата. Жирные кислоты с чётным количеством атомов углерода стимулируют синтез как соответствующих им мономеров (3-гидроксигексаноата и 3-гидроксиоктаноата), так и 3-гидроксивалерата, что позволяет получать четырёхкомпонентные ПГА, содержащие 3-гидроксибутират и 3-гидроксигексаноат в качестве основных компонентов. Было синтезировано семейство коротко- и среднецепочечных четырёх- и пятикомпонентных ПГА и проведено исследование их физико-химических и медико-биологических свойств.
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12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya, Ekaterina I., Zhila, Natalia O., Dudaev, Alexey E., Nemtsev I. V., Lukyanenko A. V., Volova, Tatiana G.
Заглавие : Modification of polyhydroxyalkanoates polymer films surface of various compositions by laser processing
Место публикации : Polymers. - 2023. - Vol. 15, Is. 3. - Ст.531. - ISSN 20734360 (eISSN), DOI 10.3390/polym15030531
Примечания : Cited References: 91. - The study was funded by the State Assignment of the Ministry of Science and Higher Education of the Russian Federation (Project No. 0287-2021-0025)
Аннотация: The results of surface modification of solvent casting films made from polyhydroxyalkanoates (PHAs) of various compositions are presented: homopolymer poly-3-hydroxybutyrate P(3HB) and copolymers comprising various combinations of 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), 4-hydroxybutyrate(4HB), and 3-hydroxyhexanoate (3HHx) monomers treated with a CO2 laser in continuous and quasi-pulsed radiation modes. The effects of PHAs film surface modification, depending on the composition and ratio of monomers according to the results of the study of SEM and AFM, contact angles of wetting with water, adhesion and growth of fibroblasts have been revealed for the laser radiation regime used. Under continuous irradiation with vector lines, melted regions in the form of grooves are formed on the surface of the films, in which most of the samples have increased values of the contact angle and a decrease in roughness. The quasi-pulse mode by the raster method causes the formation of holes without pronounced melted zones, the total area of which is lower by 20% compared to the area of melted grooves. The number of viable fibroblasts NIH 3T3 on the films after the quasi-pulse mode is 1.5–2.0 times higher compared to the continuous mode, and depends to a greater extent on the laser treatment mode than on the PHAs’ composition. The use of various modes of laser modification on the surface of PHAs with different compositions makes it possible to influence the morphology and properties of polymer films in a targeted manner. The results that have been obtained contribute to solving the critical issue of functional biodegradable polymeric materials.
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13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Menzyanova, Natalia G., Pyatina, Svetlana V., Nikolaeva, Elena D., Shabanov A. V., Nemtsev I. V., Stolyarov D. P., Dryganov, Dmitry B., Sakhnov, Eugene V., Vinokurova, Daria A., Shishatskaya, Ekaterina I.
Заглавие : Morphological aspects of monocyte/macrophage polarization on biopolymer scaffolds in atherosclerosis patients
Место публикации : J. Biotechnol. Biomater. - 2018. - Vol. 8, Is. 3. - Ст.1000284. - ISSN 2155-952X, DOI 10.4172/2155-952X.1000284
Примечания : Cited References: 67. - The study was supported by the State budget allocated to the fundamental research at the Russian Academy of Sciences (project No 01201351505).
Ключевые слова (''Своб.индексиров.''): monocytes--macrophages--cell morphology--polyhydroxyalkanoates--pha--copolymers--atherosclerosis--intravascular stenting
Аннотация: The morphotypes of human macrophages (MPh) were studied in the culture on nano-structured substrates, made from polyhydroxyalcanoates (PHAs) of various monomer compositions, prepared by casting polymer solutions on a defatted glass and followed by the solvent evaporation. Its surface relief, being further in direct contact with human cells in vitro was analyzed by AFM and SEM scanning. It was shown, that the features of micro/nano relief depend on the monomeric composition of polymer substrates. Monocytes (MNs) of patients with atherosclerosis and cardiac ischemia undergoing stenting and conventional anti-atherosclerotic therapy were harvested prior to and after stenting. After isolation MNs were cultured and transformed into MPh in direct contact with biopolymer culture substrates with different monomer composition and Nano-reliefs in comparison with culture plastic. Sub-populations of cells with characteristic morphology in each phenotypic class were described and their ratios for five samples of polymers were counted as an intermediate result in the development of “smart” material for blood vessel recovery. The results obtained allow us to assume that the processes of MPh differentiation and polarization in vitro depend not only on the features of the micro/nano relief of biopolymer substrates but also on the initial state of MNs in vivo and the general response of patients.
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14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova, Tatiana G., Kiselev, Evgeniy G., Demidenko, Alexey V., Zhila, Natalia O., Nemtsev I. V., Lukyanenko A. V.
Заглавие : Production and properties of microbial polyhydroxyalkanoates synthesized from hydrolysates of Jerusalem artichoke tubers and vegetative biomass
Коллективы : Project "Agropreparations of the new generation: a strategy of construction and realization" [075-15-2021-626]; State Assignment of the Ministry of Science and Higher Education of the Russian Federation [FSRZ-2020-0006]
Место публикации : Polymers. - 2022. - Vol. 14, Is. 1. - Ст.132. - ISSN 2073-4360(eISSN), DOI 10.3390/polym14010132
Примечания : Cited References: 93. - This study was financially supported by Project "Agropreparations of the new generation: a strategy of construction and realization" (Agreement No. 075-15-2021-626) in accordance with Resolution No. 220 of the Government of the Russian Federation of 9 April 2010, "On measures designed to attract leading scientists to the Russian institutions of higher learning" (polymer synthesis, properties), and by the State Assignment of the Ministry of Science and Higher Education of the Russian Federation No. FSRZ-2020-0006 (films production, surface properties)
Предметные рубрики: GLUCOSE-UTILIZING STRAIN
RALSTONIA-EUTROPHA
ASPERGILLUS-NIGER
ACID
Аннотация: One of the major challenges in PHA biotechnology is optimization of biotechnological processes of the entire synthesis, mainly by using new inexpensive carbon substrates. A promising substrate for PHA synthesis may be the sugars extracted from the Jerusalem artichoke. In the present study, hydrolysates of Jerusalem artichoke (JA) tubers and vegetative biomass were produced and used as carbon substrate for PHA synthesis. The hydrolysis procedure (the combination of aqueous extraction and acid hydrolysis, process temperature and duration) influenced the content of reducing substances (RS), monosaccharide contents, and the fructose/glucose ratio. All types of hydrolysates tested as substrates for cultivation of three strains—C. necator B-10646 and R. eutropha B 5786 and B 8562—were suitable for PHA synthesis, producing different biomass concentrations and polymer contents. The most productive process, conducted in 12-L fermenters, was achieved on hydrolysates of JA tubers (X = 66.9 g/L, 82% PHA) and vegetative biomass (55.1 g/L and 62% PHA) produced by aqueous extraction of sugars at 80 °C followed by acid hydrolysis at 60 °C, using the most productive strain, C. necator B-10646. The effects of JA hydrolysates on physicochemical properties of PHAs were studied for the first time. P(3HB) specimens synthesized from the JA hydrolysates, regardless of the source (tubers or vegetative biomass), hydrolysis conditions, and PHA producing strain employed, exhibited the 100–120 °C difference between the Tmelt and Tdegr, prevailing of the crystalline phase over the amorphous one (Cx between 69 and 75%), and variations in weight average molecular weight (409–480) kDa. Supplementation of the culture medium of C. necator B-10646 grown on JA hydrolysates with potassium valerate and ε-caprolactone resulted in the synthesis of P(3HB-co-3HV) and P(3HB-co-4HB) copolymers that had decreased degrees of crystallinity and molecular weights, which influenced the porosity and surface roughness of polymer films prepared from them. The study shows that JA hydrolysates used as carbon source enabled productive synthesis of PHAs, comparable to synthesis from pure sugars. The next step is to scale up PHA synthesis from JA hydrolysates and conduct the feasibility study. The present study contributes to the solution of the critical problem of PHA biotechnology—finding widely available and inexpensive substrates.
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15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T. G., Vinogradova O. N., Zhila N. O., Peterson I. V., Kiselev E. G., Vasiliev A. D., Sukovatiy A. G., Shishatskaya E. I.
Заглавие : Properties of a novel quaterpolymer P(3HB/4HB/3HV/3HHx)
Место публикации : Polymer: Elsevier, 2016. - Vol. 101. - P.67-74. - ISSN 00323861 (ISSN), DOI 10.1016/j.polymer.2016.08.048
Ключевые слова (''Своб.индексиров.''): physicochemical and mechanical properties--polyhydroxyalkanoates--quaterpolymers--biocompatibility--cell culture--chain length--chains--decomposition--3-hydroxyhexanoate--degrees of crystallinity--elongation at break--physico-chemical and mechanical properties--polyhydroxyalkanoates--quaterpolymers--short chain lengths--thermal decomposition temperature--film preparation
Аннотация: Cupriavidus eutrophus В10646 was used to synthesize a series of polyhydroxyalkanoate (PHA) quaterpolymers composed of the short-chain-length 3-hydroxybutyrate (3HB), 4-hydroxybutyrate (4HB), and 3-hydroxyvalerate (3HV) and the medium-chain-length 3-hydroxyhexanoate (3HHx). The molar fraction of 3HB in the quaterpolymers varied between 63.5 and 93.1 mol.%, 3HV – between 1.1 and 24.6 mol.%, 4HB – between 2.4 and 15.6 mol.%, and 3HHx – between 0.4 and 4.8 mol.%. The properties of PHA quaterpolymers were significantly different from those of the P(3HB) homopolymer: they had much lower degrees of crystallinity (up to 30–45%), and lower melting points and thermal decomposition temperatures, with the interval between these temperatures remaining practically unchanged. Films prepared from PHA quaterpolymers were rougher and more porous than P(3HB) films; they showed higher values of elongation at break (up to 6–113%), i.e. were more elastic. Films prepared from PHA quaterpolymers were biocompatible and had no toxic effect on mouse fibroblast NIH 3T3 cells. © 2016 Elsevier Ltd
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16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zhila N. O., Sapozhnikova K. Yu., Kiselev E. G., Vasiliev A. D., Nemtsev I. V., Shishatskaya E. I., Volova T. G.
Заглавие : Properties of degradable polyhydroxyalkanoates (PHAs) synthesized by a new strain, Cupriavidus necator IBP/SFU-1, from various carbon sources
Место публикации : Polymers. - 2021. - Vol. 13, Is. 18. - Ст.3142. - ISSN 20734360 (ISSN), DOI 10.3390/polym13183142
Примечания : Cited References: 78. - This work was financially supported by Project “Agropreparations of the new generation: a strategy of construction and realization” (Agreement No 075-15-2021-626) in accordance with Resolution No 220 of the Government of the Russian Federation of 9 April 2010, “On measures designed to attract leading scientists to the Russian institutions of higher learning” (strain isolation, polymer synthesis and investigation), and by the State Assignment of the Ministry of Science and Higher Education of the Russian Federation No. FSRZ-2020-0006 (study of film properties)
Аннотация: The bacterial strain isolated from soil was identified as Cupriavidus necator IBP/SFU-1 and investigated as a PHA producer. The strain was found to be able to grow and synthesize PHAs under autotrophic conditions and showed a broad organotrophic potential towards different carbon sources: sugars, glycerol, fatty acids, and plant oils. The highest cell concentrations (7–8 g/L) and PHA contents were produced from oleic acid (78%), fructose, glucose, and palm oil (over 80%). The type of the carbon source influenced the PHA chemical composition and properties: when grown on oleic acid, the strain synthesized the P(3HB-co-3HV) copolymer; on plant oils, the P(3HB-co-3HV-co-3HHx) terpolymer, and on the other substrates, the P(3HB) homopolymer. The type of the carbon source influenced molecular-weight properties of PHAs: P(3HB) synthesized under autotrophic growth conditions, from CO2, had the highest number-average (290 ± 15 kDa) and weight-average (850 ± 25 kDa) molecular weights and the lowest polydispersity (2.9 ± 0.2); polymers synthesized from organic carbon sources showed increased polydispersity and reduced molecular weight. The carbon source was not found to affect the degree of crystallinity and thermal properties of the PHAs. The type of the carbon source determined not only PHA composition and molecular weight but also surface microstructure and porosity of the polymer films. The new strain can be recommended as a promising P(3HB) producer from palm oil, oleic acid, and sugars (fructose and glucose) and as a producer of P(3HB-co-3HV) from oleic acid and P(3HB-co-3HV-co-3HHx) from palm oil.
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17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T., Kiselev E., Nemtsev I. V., Lukyanenko A. V., Sukovatyi A., Kuzmin A., Ryltseva G., Shishatskaya E.
Заглавие : Properties of degradable polyhydroxyalkanoates with different monomer compositions
Место публикации : Int. J. Biol. Macromol. - 2021. - Vol. 182. - P.98-114. - ISSN 01418130 (ISSN), DOI 10.1016/j.ijbiomac.2021.04.008
Примечания : Cited References: 109. - The part of the reported study on polymer synthesis and examination was funded by RFBR and KKRF [Grant No. 19-43-240012 “Biological and physical principles of production of new generation biomaterials”]. The work on production and investigation of polymer films was carried out as part of the State Assignment of the Ministry of Education and Science of the Russian Federation [Grant No. FSRZ-2020-0006]
Аннотация: Purpose: To synthesize and investigate polyhydroxyalkanoates (PHAs) with different monomer composition and percentages and polymer films prepared from them. Results: Various PHAs: homopolymer poly-3-hydroxybutyrate P(3HB) and 2-, 3-, and 4-component copolymers comprising various combinations of 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), 4-hydroxybutyrate (4HB), and 3-hydroxyhexanoate (3HHx) monomers were synthesized under specialized conditions. Relationships were found between the monomer composition of PHAs and their molecular-weight and thermal properties and degree of crystallinity. All copolymers had decreased weight average molecular weights, Mw (to 390–600 kDa), and increased values of polydispersity (3.2–4.6) compared to the P(3HB). PHA copolymers showed different thermal behavior: an insignificant decrease in Tmelt and the presence of the second peak in the melting region and changes in parameters of crystallization and glass transition. At the same time, they retained thermostability, and the difference between Tmelt and Tdegr was at least 100–120 °C. Incorporation of 4HB, 3HV, and 3HHx monomer units into the 3-hydroxybutyrate chain caused changes in the amorphous to crystalline ratio and decreased the degree of crystallinity (Cx) to 20–40%. According to the degree to which the monomers reduced crystallinity, they were ranked as follows: 4HB – 3HHx – 3HV. A unique set of films was produced; their surface properties and physical/mechanical properties were studied as dependent on PHA composition; monomers other than 3-hydroxybutyrate were found to enhance hydrophilicity, surface development, and elasticity of polymer films. Conclusion: An innovative set of PHA copolymers was synthesized and solution-cast films were prepared from them; the copolymers and films were investigated as dependent on polymer chemical composition. Results obtained in the present study contribute to the solution of a critical issue of producing degradable polymer materials.
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18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Menzyanova N. G., Pyatina S. А., Nikolaeva E. D., Shabanov A. V., Nemtsev I. V., Stolyarov D. P., Dryganov D. B., Sakhnov E. V., Shishatskaya E. I.
Заглавие : Screening of biopolymeric materials for cardiovascular surgery toxicity—Evaluation of their surface relief with assessment of morphological aspects of monocyte/macrophage polarization in atherosclerosis patients
Место публикации : Toxicol. Rep. - 2019. - Vol. 6. - P.74-90. - ISSN 22147500 (ISSN), DOI 10.1016/j.toxrep.2018.11.009
Примечания : Cited References: 85. - The study was supported by the Russian Science Foundation , Project No 17-15-01352 .
Ключевые слова (''Своб.индексиров.''): monocytes--macrophages--cell morphology--polyhydroxyalkanoates--atherosclerosis--intravascular stenting
Аннотация: The morphotypes of human macrophages (MPh) were studied in the culture on nano-structured biopolymer substrates, made from polyhydroxyalcanoates (PHAs) of five various monomer compositions, followed by the solvent evaporation. Its surface relief, which was further in direct contact with human cells in vitro, was analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). It was shown, that the features of the micro/nano relief depend on the monomeric composition of the polymer substrates. Monocytes (MN) of patients with atherosclerosis and cardiac ischemia, undergoing stenting and conventional anti-atherosclerotic therapy, were harvested prior and after stenting. MN were isolated and cultured, with the transformation into MPh in direct contact with biopolymer culture substrates with different monomer composition and nano-reliefs, and transformed into MPh, in comparison with the same process on standard culture plastic. Sub-populations of cells with characteristic morphology in each phenotypic class were described, and their quantitative ratios for each sample of polymers were counted as an intermediate result in the development of “smart” material for cardiovascular devices. The results obtained allow us to assume, that the processes of MPh differentiation and polarization in vitro depend not only on the features of the micro/nano relief of biopolymer substrates, but also on the initial state of MN in vivo and general response of patients.
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19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E. I., Nikitovic D., Shabanov A. V., Tzanakakis G. N., Tsatsakis A. M., Menzianova N. G.
Заглавие : Short-term culture of monocytes as an in vitro evaluation system for bionanomaterials designated for medical use
Место публикации : Food Chem. Toxicol.: Elsevier, 2016. - Vol. 96. - P.302-308. - ISSN 02786915 (ISSN), DOI 10.1016/j.fct.2016.08.025
Примечания : Cited References: 46
Предметные рубрики: MAGNETIC NANOPARTICLES
CELLULAR REDUCTION
PROTEIN CORONA
CELLS
MECHANOTRANSDUCTION
NANOMATERIALS
LOCALIZATION
BIOMATERIALS
CYTOSKELETON
ACTIVATION
Ключевые слова (''Своб.индексиров.''): biocompatible biopolymers--polyhydroxyalkanoates--nanomaterials--nanodiamonds--fullerenes--bio-nanomaterials--monocytes
Аннотация: We studied the feasibility of using a short-term culture of monocytes, isolated from peripheral donor blood, to assess the biological activity of different types of bionanomaterials (BNM): biodegradable polimeric particles, fiber and film substrates of micro- and nano-dimensions, fullerenes (F) and nanodiamonds (ND), which are either currently in use and/or potentially applicable in medicine. Additionally, the effect of creating a protein corona on ND and F particles was investigated. The cellular reduction of (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) is a well-established tool for assessing the viability/metabolic activity of cells. The scanning electron microscopy assay can detect fine changes in cell morphology. In the present study BNM have been shown to affect; in a size, chemical composition and morphological characteristics-dependent manner, the ability of monocytes to reduce MTT as well as their morphology. Moreover, the specific effects of ND and F on MTT reduction and cell morphology were exhibited in a dose-dependent manner and sensitive to the formation of surface protein corona. Our results suggest that short-term culture of monocytes is a sensitive model system for assessing the biological effects of BMPs in vitro. © 2016 Elsevier Ltd
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20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T. G., Zhila N. O., Shishatskaya E. I., Mironov P. V., Vasil'ev A. D., Sukovatyi A. G., Sinskey A. J.
Заглавие : The physicochemical properties of polyhydroxyalkanoates with different chemical structures
Место публикации : Polym. Sci. Ser. A: MAIK Nauka-Interperiodica / Springer, 2013. - Vol. 55, Is. 7. - P.427-437. - 11. - ISSN 0965-545X, DOI 10.1134/S0965545X13070080
Примечания : Cited References: 41
Предметные рубрики: MICROBIAL SYNTHESIS
RALSTONIA-EUTROPHA
COMAMONAS-ACIDOVORANS
AEROMONAS-HYDROPHILA
POLY(3-HYDROXYBUTYRATE-CO-4-HYDROXYBUTYRATE)
BIOSYNTHESIS
COPOLYMERS
POLY(3-HYDROXYBUTYRATE-CO-3-HYDROXYHEXANOATE)
POLYMERS
Аннотация: A set of polyhydroxyalkanoates are synthesized, and a comparative study of their physicochemical properties is performed. The molecular masses and polydispersities of polyhydroxyalkanoates are found to be independent of their chemical structures. It is shown that the temperature characteristics and degrees of crystallinity of polyhydroxyalkanoates are affected by the chemical compositions of the monomers and their quantitative contents in the polymers. The incorporation of 4-hydroxybutyrate, 3-hydroxyvalerate, and 3-hydroxyhexanoate units into the chain of poly(3-hydroxybutyrate) decreases its melting point and thermal degradation temperature relative to these parameters of a homogeneous poly(3-hydroxybutyrate) sample (175 +/- 5A degrees C and 275 +/- 5A degrees C, respectively). The higher the content of the second monomer units in the poly(3-hydroxybutirate) chain, the greater the changes. The degrees of crystallinity of polyhydroxyalkanoate copolymers are generally lower than that of poly(3-hydroxybutyrate) (75 +/- 5%). The effect on the ratio of the amorphous and crystalline phases of the copolymer samples becomes more pronounced in the series 3-hydroxy-valerate-3-hydroxyhexanoate-4-hydroxybutyrate. The prepared samples exhibit different properties ranging from rigid thermoplastic materials to engineering elastomers.
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