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1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E.I., Khlusov I.A., Volova T.G.
Заглавие : A hybrid PHB-hydroxyapatite composite for biomedical application: Production, in vitro and in vivo investigation
Место публикации : Journal of Biomaterials Science, Polymer Edition. - 2006. - Vol. 17, Is. 5. - С. 481-498. - ISSN 09205063 (ISSN) , DOI 10.1163/156856206776986242
Ключевые слова (''Своб.индексиров.''): biocompatibility--hydroxyapatite (ha)--phb-hydroxyapatite composite--polyhydroxyalkanoate (pha)--polyhydroxybutyrate (p(3hb))--properties--biocompatibility--differential thermal analysis--electron microscopy--free energy--interfacial energy--physical properties--surface properties--x ray analysis--biomedical application--physicochemical properties--polyhydroxyalkanoate (pha)--polyhydroxybutyrate (phb)--hydroxyapatite--hydroxyapatite--poly(3 hydroxybutyric acid)--polymer--biomaterial--hydroxybutyric acid--adhesion--animal cell--animal tissue--article--biomedicine--bone marrow cell--cell differentiation--cell growth--chemical structure--composite material--controlled study--crystallization--decomposition--electron microscopy--in vitro study--in vivo study--melting point--mouse--nonhuman--ossification--osteoblast--physical chemistry--priority journal--rat--strength--structure analysis--surface property--synthesis--temperature measurement--thermal analysis--tissue engineering--wettability--animal--biomechanics--bioremediation--bone prosthesis--cattle--cell culture--chemistry--cytology--differential scanning calorimetry--drug effect--human--materials testing--prostheses and orthoses--scanning electron microscopy--standard--wistar rat--murinae--animals--biocompatible materials--biodegradation, environmental--biomechanics--bone substitutes--cattle--cells, cultured--differential thermal analysis--durapatite--humans--hydroxybutyrates--materials testing--microscopy, electron, scanning--osteoblasts--prostheses and implants--rats--rats, wistar--surface properties
Аннотация: Samples of a hybrid composite of polyhydroxybutyrate (PHB), a biodegradable polyester, and hydroxyapatite (HA), with different PHB/HA ratios, have been prepared using mechanical-physical method. Electron microscopy, X-ray structure analysis and differential thermal analysis have been used to investigate the structure and physicochemical properties of the composite, depending on the PHB/HA ratio. The properties of the surface of the HA-loaded composite are significantly different from those of the pure polymer. As the HA percentage in the composite increases, free interface energy, the cohesive force, i.e., the strength of the adhesive bond between the composite surface and the water phase, and surface wettability increase. The HA percentage of the composite does not influence its melting temperature, but affects the temperature for the onset of decomposition: as the HA content increases from 0 to 10% (w/w), Td decreases from 260В°C to 225В°C. The degree of crystallinity of PHB/HA increases from 77% to 89% with an increase in the HA fraction from 10% to 50%. Functional properties of the composites have been investigated in vitro and in vivo. The best parameters of growth and differentiation of murine marrow osteoblasts are registered on PHB/HA samples containing 10% and 20% HA. In ectopic bone formation assay it has been proven that the hybrid PHB/HA composites can function as scaffolds and that bone tissue develops on their surface and in pores. В© VSP 2006.
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2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Kalacheva G.S.
Заглавие : The synthesis of hydroxybutyrate and hydroxyvalerate copolymers by the bacterium Ralstonia eutropha
Место публикации : Mikrobiologiya. - 2005. - Vol. 74, Is. 1. - С. 63-69. - ISSN 00263656 (ISSN)
Ключевые слова (''Своб.индексиров.''): ?-ketothiolase--controlled synthesis--poly(hydroxybutyrate-co-hydroxyvalerate)--ralstonia eutropha--bacteria (microorganisms)--cupriavidus necator--acetoacetyl coenzyme a--acetyl coenzyme a acyltransferase--acyl coenzyme a--acyltransferase--butyric acid derivative--carbon dioxide--fructose--hydrogen--poly(3 hydroxybutyrate) co (3 hydroxyvalerate)--poly(3-hydroxyalkanoic acid) synthase--poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate)--polyester--polyhydroxyalkanoate synthase--valeric acid derivative--article--chemistry--crystallization--culture medium--metabolism--wautersia eutropha--acetyl-coa c-acyltransferase--acyl coenzyme a--acyltransferases--butyrates--carbon dioxide--crystallization--culture media--cupriavidus necator--fructose--hydrogen--polyesters--valerates
Аннотация: The paper deals with the study of the synthesis of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV) copolymers by the bacterium Ralstonia eutropha B-5786 grown under different carbon nutrition conditions (growth on carbon dioxide, fructose, and CO2-valerate and fructose-valerate mixtures). The parameters to be analyzed included the yield of biomass, the yield, synthesis rate, and composition of copolymers, the activity of the key enzymes of polyhydroxyalkanoate (PHA) synthesis (?-ketothiolase, acetoacetyl-CoA reductase, and PHA synthase), the maximum tolerable concentration of valerate to the bacterium, and the conditions that govern the incorporation of hydroxyvalerate to copolymers. This allowed the relationship between cultivation conditions and the proportion of monomers in the copolymers to be deduced. We were able to synthesize a range of 3HB/3HV copolymers and found that the thermal characteristics and the degree of crystallinity of these copolymers depend on the molar fraction of 3HV.
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3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Kalacheva G.S., Altukhova O.V.
Заглавие : Autotrophic synthesis of polyhydroxyalkanoates by the bacteria Ralstonia eutropha in the presence of carbon monoxide
Место публикации : Applied Microbiology and Biotechnology. - 2002. - Vol. 58, Is. 5. - С. 675-678. - ISSN 01757598 (ISSN) , DOI 10.1007/s00253-002-0941-8
Ключевые слова (''Своб.индексиров.''): 3 hydroxybutyric acid--acetoacetyl coenzyme a reductase--acetyl coenzyme a acyltransferase--beta hydroxyvalerate--butyrate dehydrogenase--carbon monoxide--electrolyte--hydrogen--oxidoreductase--poly(3 hydroxybutyric acid)--poly(3 hydroxybutyric acid)synthase--polyhydroxyalkanoic acid--polymer--unclassified drug--valeric acid--bacterium--article--autotrophy--bacterial growth--bacterial strain--biomass production--controlled study--crystallization--enzyme activity--molecular weight--nonhuman--synthesis--temperature--wautersia eutropha--carbon monoxide--culture media--cupriavidus necator--fatty acids--lipids--polyesters--bacteria (microorganisms)--negibacteria--ralstonia--wautersia eutropha
Аннотация: It has been found that the carbon monoxide (CO)-resistant strain of the hydrogen bacteria Ralstonia eutropha B5786 is able to synthesise polyhydroxy-alkanoates (PHAs) in the presence of CO under autotrophic conditions. This strain, grown on model gas mixtures containing 5-25% CO (v/v), accumulates up to 70-75% (of absolutely dry matter) PHA, without significant variation in the yield coefficient on hydrogen. No suppression of the activities of the key enzymes of PHA synthesis (?-ketothiolase, acetoacetyl-CoA-reductase, butyrate dehydrogenase and poly-3-hydroxybutyrate synthase) was recorded. The PHA synthesised is a copolymer containing mostly ?-hydroxybutyrate (more than 99 mol%) with trace amounts of ?-hydroxyvalerate. The investigated properties of the polymer (molecular weight, crystallinity, temperature characteristics) do not differ from those of the polymer synthesised on electrolytic hydrogen.
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4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T.G., Vasil'ev A.D., Zeer E.P., Petrakovskaia E.A., Falaleev O.V.
Заглавие : Study of molecular structure of polyhydroxybutyrate-a termoplastic anddegradable biopolymer
Место публикации : Biofizika. - 2000. - Vol. 45, Is. 3. - С. 445-451. - ISSN 00063029 (ISSN)
Ключевые слова (''Своб.индексиров.''): carbon--hydroxybutyric acid--polyester--alcaligenes--article--chemistry--crystallization--alcaligenes--carbon--crystallization--hydroxybutyrates--polyesters
Аннотация: The molecular structure of polyhydroxybutyrate from hydrogen-oxidizing bacteria Alcaligenes eutrophus was studied by X-ray diffraction analysis. It was shown that the degree of crystallinity of various samples depends little on the conditions of their preparation and is equal to 0.62-0.76. The molecular structure of solid samples and solution of polyhydroxybutyrate in chloroform were studied by the NMR and EPR methods. The conclusion is made that the molecular structure of polyhydroxybutyrate does not depend on the features of the strain and conditions of carbon nutrition of microorganisms producing polyhydroxybutyrate. Defects induced by gamma-radiation in polyhydroxybutyrate were studied. Free radicals were isolated, and their structure was decoded.
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5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Deng L..., Markova S.V., Vysotski E.S., Liu Z.J., Lee J..., Rose J..., Wang B.C.
Заглавие : Preparation and X-ray crystallographic analysis of the Ca2+-discharged photoprotein obelin
Колич.характеристики :3 с
Место публикации : Acta Crystallogr. Sect. D-Biol. Crystallogr.: BLACKWELL MUNKSGAARD, 2004. - Vol. 60. - С. 512-514. - ISSN 0907-4449, DOI 10.1107/S090744490302852X
Примечания : Cited References: 18
Предметные рубрики: VIOLET BIOLUMINESCENCE
ANGSTROM RESOLUTION
W92F OBELIN
AEQUORIN
SEQUENCE
PROTEIN
CLONING
CDNA
Аннотация: Ca2+-regulated photoproteins belong to the EF-hand Ca2+-binding protein family. The addition of calcium ions initiates bright blue bioluminescence of the photoproteins, a result of the oxidative breakdown of coelenterazine peroxide to coelenteramide. Crystals of the Ca2+-discharged W92F mutant of obelin from Obelia longissima have been grown, representing the first crystallization of a photoprotein after the Ca2+-triggered bioluminescence. A green fluorescence observed from the crystals clearly demonstrates that coelenteramide, the bioluminescence product of coelenterazine peroxide, is bound within the protein. The diffraction pattern exhibits tetragonal Laue symmetry. Systematic absences indicate that the space group is either P4(3)2(1)2 or P4(1)2(1)2. The unit-cell parameters are a=b=53.4, c=144.0 Angstrom. The crystals diffract to 1.9 Angstrom resolution.
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6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vysotski E.S., Liu Z.J., Rose J..., Wang R.C., Lee J...
Заглавие : Preparation and X-ray crystallographic analysis of recombinant obelin crystals diffracting to beyond 1.1 angstrom
Колич.характеристики :3 с
Место публикации : Acta Crystallogr. Sect. D-Biol. Crystallogr.: MUNKSGAARD INT PUBL LTD, 2001. - Vol. 57. - С. 1919-1921. - ISSN 0907-4449, DOI 10.1107/S0907444901016523
Примечания : Cited References: 16
Предметные рубрики: PHOTOPROTEIN AEQUORIN
LONGISSIMA
EVOLUTION
CDNA
Аннотация: Crystals of recombinant obelin, the Ca2+-regulated photoprotein from the marine hydroid Obelia longissima, have been grown from a solution containing PEG 8000 and potassium phosphate. Hexamine-cobalt trichloride was used as an additive to increase the chance of crystallization. The crystals grow in a light yellow cubic form (0.5 x 0.5 x 0.45 mm) which diffracts to beyond 1.1 Angstrom resolution. The crystals belong to the space group C2, with unit-cell parameters a=83.43, b=54.92, c=52.99 Angstrom, beta = 112.00 degrees. The asymmetric unit contains one molecule. Crystals exposed to calcium ion before and after X-ray irradiation emit light, confirming that the crystals consist of an active photoprotein.
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7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zhila, Natalia, Shishatskaya, Ekaterina
Заглавие : Properties of PHA bi-, ter-, and quarter-polymers containing 4-hydroxybutyrate monomer units
Колич.характеристики :8 с
Коллективы : Russian Science Foundation [17-15-01352]
Место публикации : Int. J. Biol. Macromol.: ELSEVIER SCIENCE BV, 2018. - Vol. 111. - С. 1019-1026. - ISSN 0141-8130, DOI 10.1016/j.ijbiomac.2018.01.130. - ISSN 1879-0003(eISSN)
Примечания : Cited References:39. - The research was supported by the Russian Science Foundation (grant No. 17-15-01352).
Предметные рубрики: ALCALIGENES-FAECALIS T1
COMAMONAS-ACIDOVORANS
ENZYMATIC DEGRADATION
Ключевые слова (''Своб.индексиров.''): polyhydroxyalkanoates--4-hydroxybutyrate monomer units--physicochemical--and mechanical properties
Аннотация: The present study investigates physicochemical, mechanical, and biological properties of polyhydroxyalkanoate (PHA) copolymers containing 4-hydroxybutyrate (4HB) synthesized in Cupriavidus eutrophus B10646 culture. In poly(3-hydroxybutyrate/4-hydroxybutyrate) [P(3HB/4HB)]bipolymers, 4HB varied between 10.4 and 75.0 mol%; in poly(3-hydroxybutyrate/3-hydroxyvalerate/4-hydroxybutyrate) terpolymers, 4HB constituted 28.7-55.6 mol%; and in poly(3-hydroxybutyrate/3-hydroxyvalerate/4-hydroxybutyrate/3-hydroxyhexanoate) quaterpolymers, 4HB varied between 9.3 and 13.3 mol%. The degree of crystallinity of P(3HB/4HB) copolymers decreased consistently with an increase in 4HB content, reaching 38%. The incorporation of 3-hydroxyvalerate and 3-hydroxyhexanoate into copolymers enhanced that effect. The effect of 4HB monomer units on temperature properties of copolymers was exhibited as lowering of the melting temperature and crystallization temperature, which improved the processing-related properties of the copolymers. All copolymers containing 4HB showed enhanced elongation at break compared to poly(3-hydroxybutyrate). Polymer films prepared from PHA5 with different chemical composition had similar microstructure and porosity and had no toxic effect on mouse fibroblast NIH 3 T3 cells, proving their high biocompatibility. (C) 2018 Elsevier B.V. All rights reserved.
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8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Prudnikova S. V., Evgrafova S. Y., Volova T. G.
Заглавие : Metabolic activity of cryogenic soils in the subarctic zone of Siberia towards “green” bioplastics
Место публикации : Chemosphere: Elsevier Ltd, 2021. - Vol. 263. - Ст.128180. - ISSN 00456535 (ISSN), DOI 10.1016/j.chemosphere.2020.128180
Аннотация: The present study investigates, for the first time, the structure of the microbial community of cryogenic soils in the subarctic region of Siberia and the ability of the soil microbial community to metabolize degradable microbial bioplastic – poly-3-hydroxybutyrate [P(3HB)]. When the soil thawed, with the soil temperature between 5-7 and 9–11 °C, the total biomass of microorganisms at a 10-20-cm depth was 226–234 mg g?1 soil and CO2 production was 20–46 mg g?1 day?1. The total abundance of microscopic fungi varied between (7.4 ± 2.3) ? 103 and (18.3 ± 2.2) ? 103 CFU/g soil depending on temperature; the abundance of bacteria was several orders of magnitude greater: (1.6 ± 0.1) ? 106 CFU g?1 soil. The microbial community in the biofilm formed on the surface of P(3HB) films differed from the background soil in concentrations and composition of microorganisms. The activity of microorganisms caused changes in the surface microstructure of polymer films, a decrease in molecular weight, and an increase in the degree of crystallinity of P(3HB), indicating polymer biodegradation due to metabolic activity of microorganisms. The clear-zone technique – plating of isolates on the mineral agar with polymer as sole carbon source – was used to identify P(3HB)-degrading microorganisms inhabiting cryogenic soil in Evenkia. Analysis of nucleotide sequences of rRNA genes was performed to identify the following P(3HB)-degrading species: Bacillus pumilus, Paraburkholderia sp., Pseudomonas sp., Rhodococcus sp., Stenotrophomonas rhizophila, Streptomyces prunicolor, and Variovorax paradoxus bacteria and the Penicillium thomii, P. arenicola, P. lanosum, Aspergillus fumigatus, and A. niger fungi. © 2020 Elsevier Ltd
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9.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Jose C., Chan C. H., Winie T., Joseph B., Tharayil A., Maria H. J., Volova T., Mantia F. P.L., Rouxel D., Morreale M., Laroze D., Mathew L., Thomas S.
Заглавие : Thermomechanical analysis of isora nanofibril incorporated polyethylene nanocomposites
Место публикации : Polym.: MDPI AG, 2021. - Vol. 13, Is. 2. - Ст.299. - С. 1-15. - ISSN 20734360 (ISSN), DOI 10.3390/polym13020299
Аннотация: The research on cellulose fiber-reinforced nanocomposites has increased by an unprecedented magnitude over the past few years due to its wide application range and low production cost. However, the incompatibility between cellulose and most thermoplastics has raised significant challenges in composite fabrication. This paper addresses the behavior of plasma-modified polyethylene (PE) reinforced with cellulose nanofibers extracted from isora plants (i.e., isora nanofibrils (INFs)). The crystallization kinetics of PE–INF composites were explained using the Avrami model. The effect of cellulose nanofillers on tuning the physiochemical properties of the nanocomposite was also explored in this work. The increase in mechanical properties was due to the uniform dispersion of fillers in the PE. The investigation on viscoelastic properties confirmed good filler–matrix interactions, facilitating the stress transfer. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Jose, Cintil, Chan, Chin Han, Winie, Tan, Joseph, Blessy, Tharayil, Abhimanyu, Maria, Hanna J., Volova, Tatiana, La Mantia, Francesco Paolo, Rouxel, Didier, Morreale, Marco, Laroze, David, Mathew, Lovely, Thomas, Sabu
Заглавие : Thermomechanical Analysis of Isora Nanofibril Incorporated Polyethylene Nanocomposites
Колич.характеристики :15 с
Коллективы : project "Agro preparations of the new generation: a strategy of construction and realization" [074-02-2018-328]; Government of the Russian Federation [220]
Место публикации : Polymers: MDPI, 2021. - Vol. 13, Is. 2. - Ст.299. - ISSN 2073-4360(eISSN), DOI 10.3390/polym13020299
Примечания : Cited References:46. - This study (polymer synthesis and investigation) was financially supported by the project "Agro preparations 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 on 9 April 2010, "On measures designed to attract leading scientists to the Russian institutions of higher learning".
Аннотация: The research on cellulose fiber-reinforced nanocomposites has increased by an unprecedented magnitude over the past few years due to its wide application range and low production cost. However, the incompatibility between cellulose and most thermoplastics has raised significant challenges in composite fabrication. This paper addresses the behavior of plasma-modified polyethylene (PE) reinforced with cellulose nanofibers extracted from isora plants (i.e., isora nanofibrils (INFs)). The crystallization kinetics of PE-INF composites were explained using the Avrami model. The effect of cellulose nanofillers on tuning the physiochemical properties of the nanocomposite was also explored in this work. The increase in mechanical properties was due to the uniform dispersion of fillers in the PE. The investigation on viscoelastic properties confirmed good filler-matrix interactions, facilitating the stress transfer.
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11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gorokhovatsky A. Y., Chepurnykh T. V., Shcheglov A. S., Mokrushina Y. A., Baranova M. N., Goncharuk S. A., Purtov K. V., Petushkov V. N., Rodionova N. S., Yampolsky I. V.
Заглавие : The Recombinant Luciferase of the Fungus Neonothopanus nambi: Obtaining and Properties
Место публикации : Doklad. Biochem. Biophys.: Pleiades journals, 2021. - Vol. 496, Is. 1. - С. 52-55. - ISSN 16076729 (ISSN), DOI 10.1134/S1607672921010051
Аннотация: Abstract: A key component of the recently described bioluminescent system of higher fungi is luciferase, a new class of proteins. The properties of fungal luciferase and their relationship with its structure are interesting both for improving autoluminescent systems already created on its basis and for creating new ones. Therefore, it is extremely important to understand the spatial structure of this protein. We have performed heterologous expression and purification of Neonothopanus nambi luciferase, obtained a protein suitable for subsequent crystallization, and also determined some biochemical properties of the recombinant luciferase. © 2021, The Author(s),.
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12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gorokhovatsky, A. Yu, Chepurnykh, T., V, Shcheglov A. S., Mokrushina, Yu A., Baranova M. N., Goncharuk S. A., Purtov, K., V, Petushkov V. N., Rodionova N. S., Yampolsky, I., V
Заглавие : The Recombinant Luciferase of the Fungus Neonothopanus nambi: Obtaining and Properties
Колич.характеристики :4 с
Коллективы : Russian Science FoundationRussian Science Foundation (RSF) [16-14-00052-P]; President's grant for state support of the leading scientific schools of the Russian Federation [NSh-2605.2020.4]
Место публикации : Dokl. Biochem. Biophys.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2021. - Vol. 496, Is. 1. - С. 52-55. - ISSN 1607-6729, DOI 10.1134/S1607672921010051. - ISSN 1608-3091(eISSN)
Примечания : Cited References:10. - The work was supported by the Russian Science Foundation (project no. 16-14-00052-P). The creation of the luciferase-producing yeast strain nnLuz was supported by the President's grant for state support of the leading scientific schools of the Russian Federation (NSh-2605.2020.4).
Аннотация: A key component of the recently described bioluminescent system of higher fungi is luciferase, a new class of proteins. The properties of fungal luciferase and their relationship with its structure are interesting both for improving autoluminescent systems already created on its basis and for creating new ones. Therefore, it is extremely important to understand the spatial structure of this protein. We have performed heterologous expression and purification of Neonothopanus nambi luciferase, obtained a protein suitable for subsequent crystallization, and also determined some biochemical properties of the recombinant luciferase.
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13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T., Kiselev E., Nemtsev I., Lukyanenko А., Sukovatyi A., Kuzmin A., Ryltseva G., Shishatskaya E.
Заглавие : Properties of degradable polyhydroxyalkanoates with different monomer compositions
Место публикации : Int. J. Biol. Macromol.: Elsevier B.V., 2021. - Vol. 182. - С. 98-114. - ISSN 01418130 (ISSN), DOI 10.1016/j.ijbiomac.2021.04.008
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. © 2021 Elsevier B.V.
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14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T., Kiselev E., Nemtsev I., Lukyanenko A., Sukovatyi A., Kuzmin A., Ryltseva G., Shishatskaya E.
Заглавие : Properties of degradable polyhydroxyalkanoates with different monomer compositions
Колич.характеристики :17 с
Коллективы : RFBRRussian Foundation for Basic Research (RFBR) [19-43-240012]; Ministry of Education and Science of the Russian FederationMinistry of Education and Science, Russian Federation [FSRZ-2020-0006]
Место публикации : Int. J. Biol. Macromol.: ELSEVIER, 2021. - Vol. 182. - С. 98-114. - ISSN 0141-8130, DOI 10.1016/j.ijbiomac.2021.04.008. - ISSN 1879-0003(eISSN)
Примечания : Cited References:106. - The part of the reported study on polymer synthesis and examinationwas 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].
Предметные рубрики: PALM KERNEL OIL
RALSTONIA-EUTROPHA
BIODEGRADABLE POLYMERS
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 degrees 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 3hydroxybutyrate 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. (C) 2021 Elsevier B.V. All rights reserved.
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