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A one-dimensional model of vertical stratification of Lake Shira focussed on winter conditions and ice cover / S. N. Genova [et al.] // Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - P571-584, DOI 10.1007/s10452-010-9327-7 . - ISSN 1386-2588
Кл.слова (ненормированные):
Convective mixed layer -- Ice formation -- Ice melting -- Simplified model -- Winter profiles -- anoxic conditions -- hydrogen sulfide -- ice cover -- inhomogeneity -- meromictic lake -- numerical model -- one-dimensional modeling -- pycnocline -- salinity -- seasonality -- stratification -- vertical profile -- water column -- water temperature -- Khakassia -- Lake Shira -- Russian Federation
Аннотация: In meromictic lakes such as Lake Shira, horizontal inhomogeneity is small in comparison with vertical gradients. To determine the vertical distribution of temperature, salinity, and density of water in a deep zone of a Lake Shira, or other saline lakes, a one-dimensional (in vertical direction) mathematical model is presented. A special feature of this model is that it takes into account the process of ice formation. The model of ice formation is based on the one-phase Stefan problem with the linear temperature distribution in the solid phase. A convective mixed layer is formed under an ice cover due to salt extraction in the ice formation process. To obtain analytical solutions for the vertical distribution of temperature, salinity, and density of water, we use a scheme of vertical structure in the form of several layers. In spring, the ice melts as top and bottom. These processes are taken into account in the model. The calculated profiles of salinity and temperature of Shira Lake are in good agreement with field measurement data for each season. Additionally, we focussed on the redox zone, which is the zone in which the aerobic layers of a water column meet the anaerobic ones. Hyperactivity of plankton communities is observed in this zone in lakes with hydrogen sulphide monimolimnion, and Lake Shira is among them. The location of the redox zone in the lake, which is estimated from field measurements, coincides with a sharp increase in density (the pycnocline) during autumn and winter. During spring and summer, the redox zone is deeper than the pycnocline. The location of pycnocline calculated with the hydro physical model is in good agreement with field measurement data. В© 2010 Springer Science+Business Media B.V.

Scopus
Держатели документа:
Institute of Computational Modeling SB RAS, Akademgorodok 50/44, Krasnoyarsk 660036, Russian Federation
Krasnoyarsk, Siberian Federal University, Institute of Mathematics, Svobodny 79, Krasnoyarsk 660041, Russian Federation
Institute of Biophysics SB RAS, Akademgorodok, Krasnoyarsk 660036, Russian Federation
Federal University, Institute of Mathematics, Svobodny 79, Krasnoyarsk 660041, Russian Federation
Netherlands Institute of Ecology, Center for Limnology, Rijksstraatweg 6, Nieuwersluis 3631 AC, Netherlands : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Genova, S.N.; Belolipetskii, V.M.; Rogozin, D.Y.; Degermendzhy, A.G.; Mooij, W.M.

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The physicochemical properties of polyhydroxyalkanoates with different chemical structures / T. G. Volova [et al.] // Polymer Science - Series A. - 2013. - Vol. 55, Is. 7. - P427-437, DOI 10.1134/S0965545X13070080 . - ISSN 0965-545X
Кл.слова (ненормированные):
Amorphous and crystalline phasis -- Degrees of crystallinity -- Physicochemical property -- Poly(3-hydroxybutirate) -- Polyhydroxyalkanoate copolymer -- Temperature characteristic -- Thermal degradation temperatures -- Thermoplastic materials -- Copolymers -- Monomers -- Thermoplastic elastomers -- Structure (composition)
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 В± 5 C and 275 В± 5 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 В± 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. В© 2013 Pleiades Publishing, Ltd.

Scopus
Держатели документа:
Institute of Biophysics, Siberian Branch, Russian Academy of Sciences, Akademgorodok 50, str. 50, Krasnoyarsk 660036, Russian Federation
Institute of Fundamental Biology and Biotechnology, Siberian Federal University, Svobodnyi pr. 79, Krasnoyarsk 660041, Russian Federation
Siberian State Technological University, pr. Mira 82, Krasnoyarsk 660049, Russian Federation
Kirensky Institute of Physics, Siberian Branch, Russian Academy of Sciences, Akademgorodok 50, str. 38, Krasnoyarsk 660036, Russian Federation
Massachusetts Institute of Technology, Cambridge, MA, United States : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Volova, T.G.; Zhila, N.O.; Shishatskaya, E.I.; Mironov, P.V.; Vasil'Ev, A.D.; Sukovatyi, A.G.; Sinskey, A.J.

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Physicochemical properties of multicomponent poly(hydroxyalkanoates) / T. G. Volova, P. V. Mironov, A. D. Vasil'ev // Biophysics. - 2007. - Vol. 52, Is. 3. - P293-297, DOI 10.1134/S0006350907030062 . - ISSN 0006-3509
Кл.слова (ненормированные):
Hydroxyhexanoate -- Hydroxyvalerate -- Poly(hydroxybutyrate) -- Bacteria (microorganisms) -- Cupriavidus necator -- Insectivora
Аннотация: The properties of new five-component poly(hydroxyalkanoates) (PHA) formed by short-and medium-chain monomers synthesized by the bacterium Wautersia eutropha B5786 were studied by X-ray diffraction, IR spectroscopy, differential thermal analysis, and viscometry. The degree of crystallinity of PHA decreased from 72 to 57% as the molar fraction of hydroxyhexanoate increased from 2.5 to 18.0 mol%. The melting temperature (T m) and decomposition temperature (T d) of the multicomponent PHA are lower than those for poly(hydroxybutyrate), whose T m and T d are 168-170 and 260-265В°C, respectively. Both parameters of the multicomponent PHA decrease to 156 and 252В°C, respectively, as the hydroxyhexanoate mole fraction is raised. The effect of hydroxyhexanoate on the physicochemical properties of the PHA is similar to that of hydroxyvalerate observed previously. В© 2007 Pleiades Publishing, Inc.

Scopus
Держатели документа:
Institute of Biophysics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk 660036, Russian Federation
Siberian State Technological University, Krasnoyarsk 660049, Russian Federation
Kirenskii Institute of Physics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Volova, T.G.; Mironov, P.V.; Vasil'ev, A.D.

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A hybrid PHB-hydroxyapatite composite for biomedical application: Production, in vitro and in vivo investigation / E. I. Shishatskaya, I. A. Khlusov, T. G. Volova // Journal of Biomaterials Science, Polymer Edition. - 2006. - Vol. 17, Is. 5. - P481-498, DOI 10.1163/156856206776986242 . - ISSN 0920-5063
Кл.слова (ненормированные):
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.

Scopus
Держатели документа:
Institute of Biophysics, Siberian Branch, Russian Academy of Sciences, Akademgorodok, Krasnoyarsk 60036, Russian Federation
Tomsk State University, Tomsk 634021, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Shishatskaya, E.I.; Khlusov, I.A.; Volova, T.G.

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Physicochemical properties of two-component polyhydroxyalkanoates, 3-hydroxybutyrate-3-hydroxyvalerate copolymers / T. G. Volova [et al.] // Biophysics. - 2004. - Vol. 49, Is. 6. - P934-942 . - ISSN 0006-3509
Кл.слова (ненормированные):
Hydroxybutyrate-hydroxyvalerate copolymers -- Physicochemical properties -- Polyhydroxyalkanoates -- Structure -- Bacteria (microorganisms) -- Cupriavidus necator
Аннотация: A series of two-component polyhydroxyalkanoates composed of hydroxybutyrate-hydroxyvalerate copolymers with different monomer ratio was obtained with the use of bacteria Ralstonia eutropha B5786. The properties of the polyhydroxyalkanoates in comparison with the homopolymer of hydroxybutyric acid were studied by X-ray diffraction analysis, IR spectroscopy, differential thermal analysis, and viscometry. The ratio of crystalline to amorphous phase in the copolymers tends to unity with increasing hydroxyvalerate content. This is accompanied by a decrease in the degree of crystallinity of the copolymers from 70-80 to 45-50%, the dependence is virtually linear within the range, of hydroxyvalerate mole fraction from several to 25-30 mol%. Thermal characteristics, melting temperature (Tm) and decomposition temperature (Td), of the polyhydroxyalkanoate copolymers are lower than those for polyhydroxybutyrate, whose Tm and Td are 168-170 and 260-265В°C, respectively. Both parameters decrease to 150-160 and 200-220В°C, respectively, when the hydroxyvalerate mole fraction is raised. No distinct correlation between polymer composition and molecular weight has been revealed. Copyright В© 2004 by MAIK "Nauka/Interperiodica".

Scopus
Держатели документа:
Institute of Biophysics, Russian Academy of Sciences, Krasnoyarsk, 660036, Russian Federation
Siberian State Technological University, Krasnoyarsk, 660049, Russian Federation
Kirenskii Institute of Physics, Russian Academy of Sciences, Krasnoyarsk, 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Volova, T.G.; Plotnikov, V.F.; Shishatskaya, E.I.; Mironov, P.V.; Vasil'ev, A.D.

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Studies of Biodegradation of Microbial Polyhydroxyalkanoates / T. G. Volova [и др.] // Prikladnaya Biokhimiya i Mikrobiologiya. - 1998. - Vol. 34, Is. 5. - С. 543 . - ISSN 0555-1099
Аннотация: Biodegradation of polyhydroxyalkanoates (PHA) - polymers of hydroxylated fatty acids - differing in chemical composition, crystallinity, melting temperature, and molecular weight was studied in soil and water environments under conditions of varying ambient temperature and pH. Under similar conditions, homogeneous films of polyhydroxybutyrate (PHB) with different initial properties were degraded at virtually equal rates. Hydroxybutyrate-hydroxyvalerate copolymers with a lower crystallinity and different microstructure in comparison to PHB were degraded at a 20 to 30% higher rate on average. The ambient temperature significantly influenced the rate of PHA biodegradation.

Scopus
Держатели документа:
Institute of Biophysics, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Volova, T.G.; Belyaeva, O.G.; Plotnikov, V.F.; Puzyr', A.P.

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Studies of biodegradation of microbial polyhydroxyalkanoates / T. G. Volova [et al.] // Applied Biochemistry and Microbiology. - 1998. - Vol. 34, Is. 5. - P488-492 . - ISSN 0003-6838
Аннотация: Biodegradation of polyhydroxyalkanoates (PHA) - polymers of hydroxylated fatty acids - differing in chemical composition, crystallinity, melting temperature, and molecular weight was studied in soil and water environments under conditions of varying ambient temperature and pH. Under similar conditions, homogeneous films of polyhydroxybutyrate (PHB) with different initial properties were degraded at virtually equal rates. Hydroxybutyrate-hydroxyvalerate copolymers with a lower crystallinity and different microstructure in comparison to PHB were degraded at a 20 to 30% higher rate on average. The ambient temperature significantly influenced the rate of PHA biodegradation.

Scopus
Держатели документа:
Institute of Biophysics, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Volova, T.G.; Belyaeva, O.G.; Plotnikov, V.F.; Puzyr', A.P.

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A glucose-utilizing strain, cupriavidus euthrophus B-10646: Growth kinetics, characterization and synthesis of multicomponent PHAs / T. Volova [et al.] // PLoS ONE. - 2014. - Vol. 9, Is. 2, DOI 10.1371/journal.pone.0087551 . - ISSN 1932-6203
Кл.слова (ненормированные):
3 hydroxybutyrate 3 hydroxyhexanoate 3 hydroxyvalerate copolymer -- 3 hydroxybutyrate 4 hydroxybutyrate 3 hydroxyvalerate copolymer -- copolymer -- gamma butyrolactone -- glucose -- hexanoic acid -- poly(3 hydroxybutyric acid) -- polyhydroxyalkanoic acid -- polystyrene -- propionic acid -- unclassified drug -- valeric acid -- animal cell -- article -- bacterial growth -- bacterium culture -- cell adhesion -- cell proliferation -- crystal structure -- culture optimization -- Cupriavidus -- Cupriavidus euthrophus -- decomposition -- elasticity -- film -- glucose utilization -- kinetics -- mechanics -- melting point -- mouse -- nonhuman -- nucleotide sequence -- physical chemistry -- polymerization -- strength -- synthesis
Аннотация: This study investigates kinetic and production parameters of a glucose-utilizing bacterial strain, C. eutrophus B-10646, and its ability to synthesize PHA terpolymers. Optimization of a number of parameters of bacterial culture (cell concentration in the inoculum, physiological activity of the inoculum, determined by the initial intracellular polymer content, and glucose concentration in the culture medium during cultivation) provided cell concentrations and PHA yields reaching 110 g/L and 80%, respectively, under two-stage batch culture conditions. Addition of precursor substrates (valerate, hexanoate, propionate, ?-butyrolactone) to the culture medium enabled synthesis of PHA terpolymers, P(3HB/3HV/4HB) and P(3HB/ 3HV/3HHx), with different composition and different molar fractions of 3HB, 3HV, 4HB, and 3HHx. Different types of PHA terpolymers synthesized by C. eutrophus B-10646 were used to prepare films, whose physicochemical and physical-mechanical properties were investigated. The properties of PHA terpolymers were significantly different from those of the P3HB homopolymer: they had much lower degrees of crystallinity and lower melting points and thermal decomposition temperatures, with the difference between these temperatures remaining practically unchanged. Films prepared from all PHA terpolymers had higher mechanical strength and elasticity than P3HB films. In spite of dissimilar surface structures, all films prepared from PHA terpolymers facilitated attachment and proliferation of mouse fibroblast NIH 3T3 cells more effectively than polystyrene and the highly crystalline P3HB. Copyright: © 2014 Volova et al.

Scopus
Держатели документа:
Institute of Biophysics of Siberian Branch of Russian Academy of Sciences, Krasnoyarsk, Russian Federation
Siberian Federal University, Krasnoyarsk, Russian Federation
Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Science, Moscow, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Volova, T.; Kiselev, E.; Vinogradova, O.; Nikolaeva, E.; Chistyakov, A.; Sukovatiy, A.; Shishatskaya, E.

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A Glucose-Utilizing Strain, Cupriavidus euthrophus B-10646: Growth Kinetics, Characterization and Synthesis of Multicomponent PHAs [Text] / T. . Volova [et al.] // PLoS One. - 2014. - Vol. 9, Is. 2. - Ст. e87551, DOI 10.1371/journal.pone.0087551. - Cited References: 64. - This study was financially supported by Project "Biotechnologies of novel biomaterials: Innovative Biopolymers and Biomedicine Devices" (Agreement No. 11.G34.31.0013 with Amendment No. 1 of 15 February 2013) 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." The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. . - ISSN 1932-6203

РУБ Multidisciplinary Sciences
Рубрики:
RALSTONIA-EUTROPHA
   BIODEGRADABLE POLYHYDROXYALKANOATES
   AEROMONAS-HYDROPHILA
   ESCHERICHIA-COLI
   MOLECULAR-WEIGHT
   SURFACE-ENERGY
   NORTH PACIFIC
   TERPOLYESTER
   BIOSYNTHESIS
   POLY(3-HYDROXYBUTYRATE-CO-3-HYDROXYVALERATE-CO-3-HYDROXYHEXANOATE)
Аннотация: This study investigates kinetic and production parameters of a glucose-utilizing bacterial strain, C. eutrophus B-10646, and its ability to synthesize PHA terpolymers. Optimization of a number of parameters of bacterial culture (cell concentration in the inoculum, physiological activity of the inoculum, determined by the initial intracellular polymer content, and glucose concentration in the culture medium during cultivation) provided cell concentrations and PHA yields reaching 110 g/L and 80%, respectively, under two-stage batch culture conditions. Addition of precursor substrates (valerate, hexanoate, propionate, c-butyrolactone) to the culture medium enabled synthesis of PHA terpolymers, P(3HB/3HV/4HB) and P(3HB/3HV/3HHx), with different composition and different molar fractions of 3HB, 3HV, 4HB, and 3HHx. Different types of PHA terpolymers synthesized by C. eutrophus B-10646 were used to prepare films, whose physicochemical and physicalmechanical properties were investigated. The properties of PHA terpolymers were significantly different from those of the P3HB homopolymer: they had much lower degrees of crystallinity and lower melting points and thermal decomposition temperatures, with the difference between these temperatures remaining practically unchanged. Films prepared from all PHA terpolymers had higher mechanical strength and elasticity than P3HB films. In spite of dissimilar surface structures, all films prepared from PHA terpolymers facilitated attachment and proliferation of mouse fibroblast NIH 3T3 cells more effectively than polystyrene and the highly crystalline P3HB.

WOS
Держатели документа:
[Volova, Tatiana
Kiselev, Evgeniy
Nikolaeva, Elena
Sukovatiy, Aleksey
Shishatskaya, Ekaterina] Russian Acad Sci, Inst Biophys, Siberian Branch, Krasnoyarsk, Russia
[Volova, Tatiana
Vinogradova, Olga
Shishatskaya, Ekaterina] Siberian Fed Univ, Krasnoyarsk, Russia
[Chistyakov, Anton] Russian Acad Sci, Shemyakin Ovchinnikov Inst Bioorgan Chem, Moscow, Russia
ИБФ СО РАН : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Volova, T...; Kiselev, E...; Vinogradova, O...; Nikolaeva, E...; Chistyakov, A...; Sukovatiy, A...; Shishatskaya, E...; Project "Biotechnologies of novel biomaterials: Innovative Biopolymers and Biomedicine Devices" [11.G34.31.0013]

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10.

Physicochemical properties of two-component polyhydroxyalkanoates [Poly(3HB/3HV)] [Текст] / T. G. Volova [и др.] // Biofizika. - 2004. - Vol. 49, Is. 6. - P. 1038-1046. - Cited References: 21 . - ISSN 0006-3029

РУБ Biophysics
Рубрики:
BACTERIAL POLYHYDROXYALKANOATES
POLYESTERS
Кл.слова (ненормированные):
polyhydroxyalkanoates -- copolymers of hydroxybutyrate and hydroxyvalerate -- structure -- physicochemical properties
Аннотация: A series of two-component polyhydroxyalkanoates consisting of hydroxybutyrate and hydroxyvalerate monomer at different ratios were synthesized using the bacterium Ralstonia eutropha B5786. The properties of polyhydroxyalkanoates were compared with those of the homopolymer of hydroxybutyric acid by X-ray structure analysis, IR spectroscopy, differential scanning calorimetry, and viscosimetry. With an increase in the molar fraction of hydroxyvalerate, an equalization of the ratio of the crystalline and amorphous phases in the copolymer was observed. The degree of crystallinity of the polymer decreased from 70-80 to 45-50%; in the range of an increase in the hydroxyvalerate molar fraction from several to 25-30 mol %, the dependence was linear. The temperature characteristics, the melting temperature (T-m), and the degradation temperature (T-d) were lower in polyhydroxyalkanoates than in polyhydroxybutyrate, for which T-m and T-d were 168-170 and 260-265degreesC, respectively. In the copolymer, as the molar fraction of hydroxyvalerate grew, both parameters decreased. In the range of variation of monomer ratio studied, they decreased to 150-160 and 200-220degreesC, respectively. No distinct correlation between the composition of the polymer and its molecular mass was found.

WOS
Держатели документа:
Russian Acad Sci, Inst Biophys, Siberian Div, Krasnoyarsk, Russia
Siberian State Technol Univ, Krasnoyarsk, Russia
Russian Acad Sci, LV Kirensky Phys Inst, Siberian Div, Krasnoyarsk, Russia
ИФ СО РАН
ИБФ СО РАН : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Volova, T.G.; Plotnikov, V.F.; Shishatskaya, E.I.; Mironov, P.V.; Vasil'ev, A.D.

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11.

Properties of a novel quaterpolymer P(3HB/4HB/3HV/3HHx) / T. G. Volova [et al.] // Polymer. - 2016. - Vol. 101. - P67-74, DOI 10.1016/j.polymer.2016.08.048 . - ISSN 0032-3861
Кл.слова (ненормированные):
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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WOS
Держатели документа:
Siberian Federal University, 79 Svobodnyi Avenue, Krasnoyarsk, Russian Federation
Institute of Biophysics of Siberian Branch of Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, Russian Federation
Institute of Chemistry and Chemical Technology of Siberian Branch of Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, Russian Federation
L.V. Kirensky Institute of Physics of Siberian Branch of Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, Russian Federation

Доп.точки доступа:
Volova, T. G.; Vinogradova, O. N.; Zhila, N. O.; Peterson, I. V.; Kiselev, E. G.; Vasiliev, A. D.; Sukovatiy, A. G.; Shishatskaya, E. I.

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12.

Contrasting relationship between macro- and microviscosity of the gelatin- and starch-based suspensions and gels [Text] / D. V. Gulnov, E. V. Nemtseva, V. A. Kratasyuk // Polym. Bull. - 2016. - Vol. 73, Is. 12. - P3421-3435, DOI 10.1007/s00289-016-1664-9. - Cited References:42. - Authors thank Alexander Kheruvimov (REC "Composite Materials and Structures", SUSU, Chelyabinsk, Russia) for assistance in rheological experiments. The research was partially supported by the grants No. 11.G34.31.0058 and 1762 from The Ministry of Education and Science of the Russian Federation and by the state budget allocated to the fundamental research at the Russian Academy of Sciences (Project No. 01201351504). . - ISSN 0170-0839. - ISSN 1436-2449

РУБ Polymer Science
Рубрики:
FLUORESCENT MOLECULAR ROTORS
INTRACELLULAR VISCOSITY
DRUG-DELIVERY
Кл.слова (ненормированные):
Biopolymer -- Gelatin -- Starch -- Physical gel -- Microviscosity -- Molecular -- rotor
Аннотация: The problem of correlation between rheological properties in macro- and micro- scales of media with biopolymers of polypeptide (gelatin) and polysaccharide (starch) nature is investigated. The viscosity of the biopolymer solutions with concentrations 0.5-5 wt% was estimated by standard rotational rheometry technique and with fluorescent molecular rotor at 15-50 A degrees C. Opposite trends were observed for relationship between microviscosity eta (m) and macroviscosity eta for two biopolymers: eta (m) << eta for gelatin and eta (m) >> eta for starch solutions. The temperature dependence of eta (m) followed the monoexponential decay law in all samples over the whole temperature range indicating insensitivity of microviscosity to gel mesh melting under heating. The dissimilarity of macro- and micro-rheological properties of gelatin and starch-containing media is discussed in terms of difference in architecture of the gels.

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Держатели документа:
Siberian Fed Univ, Lab Bioluminescent Biotechnol, Krasnoyarsk 660041, Russia.
Inst Biophys SB RAS, Krasnoyarsk 660036, Russia.

Доп.точки доступа:
Gulnov, Dmitry V.; Nemtseva, Elena V.; Kratasyuk, Valentina A.; Ministry of Education and Science of the Russian Federation [11.G34.31.0058, 1762]; Russian Academy of Sciences [01201351504]

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13.

Physicochemical properties of multicomponent polyhydroxyalkanoates: Novel aspects / T. G. Volova [et al.] // Polym. Sci. Ser. A. - 2017. - Vol. 59, Is. 1. - P98-106, DOI 10.1134/S0965545X17010163 . - ISSN 0965-545X
Кл.слова (ненормированные):
Glycols -- Medical problems -- Melting -- Molecular mass -- Monomers -- Polymers -- Chemical compositions -- Degree of crystallinity -- Degrees of crystallinity -- Multi-component polyhydroxyalkanoates -- Physicochemical property -- Polyhydroxyalkanoates -- Temperature intervals -- Thermal degradation temperatures -- Organic polymers
Аннотация: The physicochemical properties such as the degree of crystallinity and temperature and molecularmass characteristics of a number of polyhydroxyalkanoates of various chemical composition synthesized on a complex carbon substrate by bacteria Cupriavidus eutrophus В10646 have been investigated. Two-, three-, and four-component copolymer samples have different sets and ratios of monomers with various lengths of carbon chains: 3-hydroxybutyrate (3HB), 4-hydroxybutyrate (4HB), 3-hydroxyvalerate (3HV), 3-hydroxyhexanoate (3HH), 3-hydroxy-4-methyl valerate (3H4MV), and diethylene glycol (DEG). It has been shown that weight-average molar mass Мw and polydispersity vary in a wide range with no correlation existing with the composition of copolymer polyhydroxyalkanoates and that thermal stability is preserved in the temperature interval between the melting temperature and the thermal degradation temperature from 100 to 120–140°С. The composition and ratio of monomers most notably affect the degree of crystallinity of polyhydroxyalkanoates. Significant differences between the degrees of crystallinity of three- and four-component polyhydroxyalkanoates have been found for the first time. The degree of crystallinity for copolymers P(3HB/3HV/4HB) is 9–22%, and the degree of crystallinity for copolymers P(3HB/3HV/3HH) and P(3HB/3GV/3H4MV) is 41–63%; this value is close to the degree of crystallinity for diblock copolymers P(3HB)/DEG, which is 56–69%. For the four-component copolymers P(3HB/3GV/4HB/3HH), the degree of crystallinity is 30–41%. The values of Мw for the copolymers P(3HB/DEG) are inhomogeneous and the polymers contain fractions uneven with respect to molecular mass: a high-molecular-mass polymer (Мw from 2700 to 4900 kDa) and a low-molecular-mass polymer (Мw = 46–167 kDa). For the copolymers P(3HB)/DEG and P(3HB/3HV/3H4MV), two peaks are observed in the region of melting with the gap between these peaks being 4–20°С. All of the types of copolymer samples, regardless of the monomer ratio, show an increase in elongation at break against the background of a decrease in tensile stress and Young’s modulus, with these effects being pronounced to different extents. On the whole, the properties of multicomponent polyhydroxyalkanoates differ appreciably. © 2017, Pleiades Publishing, Ltd.

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Держатели документа:
Institute of Biophysics, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, Russian Federation

Доп.точки доступа:
Volova, T. G.; Vinogradova, O. N.; Zhila, N. O.; Kiselev, E. G.; Peterson, I. V.; Vasil’ev, A. D.; Sukovatyi, A. G.; Shishatskaya, E. I.

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14.

The novel extremely psychrophilic luciferase from Metridia longa: Properties of a high-purity protein produced in insect cells / M. D. Larionova, S. V. Markova, E. S. Vysotski // Biochem. Biophys. Res. Commun. - 2017. - Vol. 483, Is. 1. - P772-778, DOI 10.1016/j.bbrc.2016.12.067. - Cited References:24. - The cloning of cDNAs encoding MLuc2 isoforms of M. longa was supported by Bayer AG (Germany) and the state budget allocated to the fundamental research at the Russian Academy of Sciences (project No. 01201351504); all other studies were funded by RFBR and Government of Krasnoyarsk Territory according to the research project No. 16-44-242099. . - ISSN 0006-291X. - ISSN 1090-2104

РУБ Biochemistry & Molecular Biology + Biophysics
Рубрики:
CDNA CLONING
EXPRESSION
ENZYME
Кл.слова (ненормированные):
Bioluminescence -- Coelenterazine -- Bioluminescent reporter -- Psychrophilic -- enzyme -- Molecular adaptation
Аннотация: The bright bioluminescence of copepod Metridia longa is conditioned by a small secreted coelenterazinedependent luciferase (MLuc). To date, three isoforms of MLuc differing in length, sequences, and some properties were cloned and successfully applied as high sensitive bioluminescent reporters. In this work, we report cloning of a novel group of genes from M. longa encoding extremely psychrophilic isoforms of MLuc (MLuc2-type). The novel isoforms share only similar to 54-64% of protein sequence identity with the previously cloned isoforms and, consequently, are the product of a separate group of paralogous genes. The MLuc2 isoform with consensus sequence was produced as a natively folded protein using baculovirus/ insect cell expression system, purified, and characterized. The MLuc2 displays a very high bioluminescent activity and high thermostability similar to those of the previously characterized M. longa luciferase isoform MLuc7. However, in contrast to MLuc7 revealing the highest activity at 12-17 degrees C and 0.5 M NaCl, the bioluminescence optima of MLuc2 isoforms are at similar to 5 degrees C and 1 M NaCl. The MLuc(2) adaptation to cold is also accompanied by decrease of melting temperature and affinity to substrate suggesting a more conformational flexibility of a protein structure. The luciferase isoforms with different temperature optima may provide adaptability of the M. longa bioluminescence to the changes of water temperature during diurnal vertical migrations. (C) 2016 Elsevier Inc. All rights reserved.

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Держатели документа:
Fed Res Ctr Krasnoyarsk Sci Ctr SB RAS, Inst Biophys SB RAS, Photobiol Lab, Krasnoyarsk, Russia.
Siberian Fed Univ, Krasnoyarsk, Russia.

Доп.точки доступа:
Larionova, Marina D.; Markova, Svetlana V.; Vysotski, Eugene S.; Bayer AG (Germany); Russian Academy of Sciences [01201351504]; RFBR; Government of Krasnoyarsk Territory [16-44-242099]

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15.

Properties of PHA bi-, ter-, and quarter-polymers containing 4-hydroxybutyrate monomer units / N. Zhila, E. Shishatskaya // Int. J. Biol. Macromol. - 2018. - Vol. 111. - P1019-1026, DOI 10.1016/j.ijbiomac.2018.01.130. - Cited References:39. - The research was supported by the Russian Science Foundation (grant No. 17-15-01352). . - ISSN 0141-8130. - ISSN 1879-0003

РУБ Biochemistry & Molecular Biology + Chemistry, Applied + Polymer Science
Рубрики:
ALCALIGENES-FAECALIS T1
COMAMONAS-ACIDOVORANS
ENZYMATIC DEGRADATION
Кл.слова (ненормированные):
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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Держатели документа:
Siberian Fed Univ, 79 Svobodnyi Ave, Krasnoyarsk 660041, Russia.
RAS, Krasnoyarsk Sci Ctr, Fed Res Ctr, Inst Biophys,SB, Krasnoyarsk 660036, Russia.

Доп.точки доступа:
Zhila, Natalia; Shishatskaya, Ekaterina; Russian Science Foundation [17-15-01352]

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16.

The effect of deicing salt solutes on Moina macrocopa and Allium cepa in a toxicity test experiment / T. S. Lopatina, Y. V. Aleksandrova, O. V. Anishchenko [и др.] // Vestn. Tomsk. Gos. Univ. Biol. - 2020. - Is. 51. - С. 162-178, DOI 10.17223/19988591/51/9 . - ISSN 1998-8591
Кл.слова (ненормированные):
Aquatic ecosystems -- Cladocera, Allium-test -- Salinity -- Toxicity test
Аннотация: Chloride salts are the most commonly used deicing materials for winter maintenance of roads. Numerous studies indicate a significant increase in the salinity of aquatic ecosystems associated with the long-term use of deicing materials in countries located in cold climates. The functioning of ecosystems largely depends on salinity, since salinity is one of the key factors determining the species composition, the structure of food webs and the productivity of aquatic communities. Given the growing threat of salinization of groundwater and surface waters, it is extremely important to study the effect of deicing materials on the biota and functioning of aquatic ecosystems. The aim of this research is to determine the threshold concentrations of solutions of the deicing salt mixture “Bionord” containing sodium and calcium chlorides, at which negative effects on the development of animal and plant test objects are observed. In this study, we used the salt-containing mixture “Bionord” as a model deicer. Similarly, with the most commonly used ice melting chemicals, the «Bionord» salt mixture contains a large amount of sodium and calcium chlorides (about 85% of the total weight). To evaluate the toxicity of the deicer solutions, we used acute and chronic toxicity tests with cladoceran Moina macrocopa (Straus, 1820) (Cladocera: Moinidae) and standard onion-based test with Allium cepa L. (Liliopsida: Amaryllidaceae) (Allium-test). In acute and chronic toxicity tests with Cladocera, the females on the first day of their life (body size 0.5-0.6 mm) were placed individually in jars with aged (not less than for 72 h) tap water with a volume of 20 ml with the addition of a deicer at a certain concentration. A group of animals that was placed in the medium without the deicer was used as a control. In the acute toxicity tests, we used the following concentration of the deicer: 1.3; 2.5; 4.0, 5.0; 6.0; 8.0; 10.0 g/l. The mortality of animals was recorded 24 and 48 hours after the start of the experiment. The concentration of the deicer (LC50) at which 50% of animals was observed to die, compared to the control, was determined in the acute toxicity test. In a chronic toxicity test, animals were tested in the following range of concentrations of the deicer: 0.3; 0.6; 1.3; 2.5; 5.0; 6.0 and 8.0 g/l. The chronic toxicity test was conducted until the death of all test animals. Based on the data obtained in the chronic toxicity test, the specific growth rate of juvenile females, average fecundity, and average life span of M. macrocopa were calculated for each concentration of the deicer. Bulbs of onions of the Stuttgartenrisen variety with a diameter of 1.8 ± 0.1 cm and a weight of 2.27 ± 0.17 g were used in the onion test. Bulbs with their bottoms were placed in test tubes containing 20 ml of a solute of the deicer or tap water for 48 hours. Three bulbs were tested for each concentration and for the control. The following concentrations of the deicer were used in the onion test: 1.0; 2.5; 5.0; 7.0; 10.0; 15.0; 20.0; 50.0 g/l. The general toxic and cytotoxic effects were evaluated in the onion test. The average root length and the total root length on each bulb were used as indicators of the total toxicity of the solutions of deicer. To evaluate proliferative activity, we calculated the mitotic index as the fraction of dividing cells in the apical root meristem to the total number of cells. Based on the results of the experiments, we determined median effective mixture concentrations (EC50) at which there is a 50% decrease, compared to the control, in the values of root growth indicators: average root length, sum of root lengths on each bulb and mitotic index. Median lethal concentration (LC50) of the deicing salt determined in the 48-hour acute toxicity test with females of M. macrocopa was equal to 5.1 g/l. In the chronic test, we showed that the exposure to the solutions of the deicing salt in the range of concentrations from 0.3 to 5.0 g/l does not affect the life span, specific growth rate of juveniles and fecundity of females of M. macrocopa. The median effective concentration (EC50) of the deicing salt determined in the Allium-tests were 6.3, 5.2 and 10.4 g/l for the sum of root lengths, average root length on each bulb and proliferative activity at the tips of roots (mitotic index), respectively (See Table 1 and 2). Complete inhibition of onion root growth was observed at the concentration of the decider equal to 20 g/l, while the death of all test animals in the acute toxicity test occurred at the concentration of the deicer equal to 8,0 g/l (See Fig. 1). Thus, we demonstrated that similar concentrations of the deicer induced 50% inhibition of the growth of onion roots and 50% mortality of cladocerans. These values, in general, corresponded to a critical salinity of 5-8 % above which qualitative changes occur both in the external and internal condition of aquatic animals. The electrical conductivity of the deicer solutions, which had a negative effect on the selected test species, coincides with the previously obtained values of the electrical conductivity of sodium chloride solutions harmful to cladocerans. We can assume that the main mechanism of the effect of the deicing material that we study is associated with the biological effect of its chlorine and sodium salts. Taking this into account, the value of electrical conductivity measured for solutions of deicing salt can be used to assess its negative potential effects. We estimated that in the absence of timely cleaning, regulated by the rules for using the material, the runoff from each square meter of the treated surface can lead to the pollution of 8-13 liters of fresh water. Thus, the basic requirement for the use of deicing salts on roads is the need to comply with the cleaning regime of the treated surfaces. Otherwise, the gradual accumulation of sodium and calcium chlorides in water bodies can cause an increase in salinity which will affect the survival of freshwater aquatic organisms and lead to serious disturbances in the functioning of aquatic ecosystems. © 2020 Tomsk State University. All rights reserved.

Scopus
Держатели документа:
Laboratory of Ecosystem Biophysics, Institute of Biophysics, Federal Research Centre Krasnoyarsk Scientific Centre, Siberian Branch, Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, 660036, Russian Federation
Laboratory of Bioluminescent and Environmental Technologies, Institute of Biophysics, Federal Research Centre Krasnoyarsk Scientific Centre, Siberian Branch, Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, 660036, Russian Federation
Analytical Laboratory, Institute of Biophysics, Federal Research Centre Krasnoyarsk Scientific Centre, Siberian Branch, Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, 660036, Russian Federation
Department of Biophysics, School of Fundamental Biology and Biotechnology, Siberian Federal University, 79 Svobodniy Ave, Krasnoyarsk, 660041, Russian Federation
Laboratory of Ecosystem Biophysics, Institute of Biophysics, Federal Research Centre Krasnoyarsk Scientific Centre, Siberian Branch, Russian Academy of Sciences, 50/50 Akademgorodok, Krasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Lopatina, T. S.; Aleksandrova, Y. V.; Anishchenko, O. V.; Gribovskaya, I. V.; Oskina, N. A.; Zotina, T. A.; Zadereev, E. S.

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17.

РУБ Biology + Ecology
Рубрики:
DAPHNIA-MAGNA
   NACL SALINITY
   ROAD SALTS
   WATER
   FRESH
   CHLORIDE
Кл.слова (ненормированные):
salinity -- toxicity test -- Cladocera -- Allium-test -- aquatic ecosystems
Аннотация: Chloride salts are the most commonly used deicing materials for winter maintenance of roads. Numerous studies indicate a significant increase in the salinity of aquatic ecosystems associated with the long-term use of deicing materials in countries located in cold climates. The functioning of ecosystems largely depends on salinity, since salinity is one of the key factors determining the species composition, the structure of food webs and the productivity of aquatic communities. Given the growing threat of salinization of groundwater and surface waters, it is extremely important to study the effect of deicing materials on the biota and functioning of aquatic ecosystems. The aim of this research is to determine the threshold concentrations of solutions of the deicing salt mixture "Bionord" containing sodium and calcium chlorides, at which negative effects on the development of animal and plant test objects are observed. In this study, we used the salt-containing mixture "Bionord" as a model deicer. Similarly, with the most commonly used ice melting chemicals, the "Bionord" salt mixture contains a large amount of sodium and calcium chlorides (about 85% of the total weight). To evaluate the toxicity of the deicer solutions, we used acute and chronic toxicity tests with cladoceran Moina macrocopa (Straus, 1820) (Cladocera: Moinidae) and standard onion-based test with Allium cepa L. (Liliopsida: Amaryllidaceae) (Allium-test). In acute and chronic toxicity tests with Cladocera, the females on the first day of their life (body size 0.5-0.6 mm) were placed individually in jars with aged (not less than for 72 h) tap water with a volume of 20 ml with the addition of a deicer at a certain concentration. A group of animals that was placed in the medium without the deicer was used as a control. In the acute toxicity tests, we used the following concentration of the deicer: 1.3; 2.5; 4.0, 5.0; 6.0; 8.0; 10.0 g/l. The mortality of animals was recorded 24 and 48 hours after the start of the experiment. The concentration of the deicer (LC50) at which 50% of animals was observed to die, compared to the control, was determined in the acute toxicity test. In a chronic toxicity test, animals were tested in the following range of concentrations of the deicer: 0.3; 0.6; 1.3; 2.5; 5.0; 6.0 and 8.0 g/l. The chronic toxicity test was conducted until the death of all test animals. Based on the data obtained in the chronic toxicity test, the specific growth rate of juvenile females, average fecundity, and average life span of M. macrocopa were calculated for each concentration of the deicer. Bulbs of onions of the Stuttgartenrisen variety with a diameter of 1.8 +/- 0.1 cm and a weight of 2.27 +/- 0.17 g were used in the onion test. Bulbs with their bottoms were placed in test tubes containing 20 ml of a solute of the deicer or tap water for 48 hours. Three bulbs were tested for each concentration and for the control. The following concentrations of the deicer were used in the onion test: 1.0; 2.5; 5.0; 7.0; 10.0; 15.0; 20.0; 50.0 g/l. The general toxic and cytotoxic effects were evaluated in the onion test. The average root length and the total root length on each bulb were used as indicators of the total toxicity of the solutions of deicer. To evaluate proliferative activity, we calculated the mitotic index as the fraction of dividing cells in the apical root meristem to the total number of cells. Based on the results of the experiments, we determined median effective mixture concentrations (EC50) at which there is a 50% decrease, compared to the control, in the values of root growth indicators: average root length, sum of root lengths on each bulb and mitotic index. Median lethal concentration (LC50) of the deicing salt determined in the 48-hour acute toxicity test with females of Al. macrocopa was equal to 5.1 g/l. In the chronic test, we showed that the exposure to the solutions of the deicing salt in the range of concentrations from 0.3 to 5.0 g/l does not affect the life span, specific growth rate of juveniles and fecundity of females of M. macrocopa. The median effective concentration (EC50) of the deicing salt determined in the Allium-tests were 6.3, 5.2 and 10.4 g/l for the sum of root lengths, average root length on each bulb and proliferative activity at the tips of roots (mitotic index), respectively (See Table 1 and 2). Complete inhibition of onion root growth was observed at the concentration of the decider equal to 20 g/l, while the death of all test animals in the acute toxicity test occurred at the concentration of the deicer equal to 8,0 g/l (See Fig. 1). Thus, we demonstrated that similar concentrations of the deicer induced 50% inhibition of the growth of onion roots and 50% mortality of cladocerans. These values, in general, corresponded to a critical salinity of 5-8 %o above which qualitative changes occur both in the external and internal condition of aquatic animals. The electrical conductivity of the deicer solutions, which had a negative effect on the selected test species, coincides with the previously obtained values of the electrical conductivity of sodium chloride solutions harmful to cladocerans. We can assume that the main mechanism of the effect of the deicing material that we study is associated with the biological effect of its chlorine and sodium salts Taking this into account, the value of electrical conductivity measured for solutions of deicing salt can be used to assess its negative potential effects. We estimated that in the absence of timely cleaning, regulated by the rules for using the material, the runoff from each square meter of the treated surface can lead to the pollution of 8-13 liters of fresh water. Thus, the basic requirement for the use of deicing salts on roads is the need to comply with the cleaning regime of the treated surfaces. Otherwise, the gradual accumulation of sodium and calcium chlorides in water bodies can cause an increase in salinity which will affect the survival of freshwater aquatic organisms and lead to serious disturbances in the functioning of aquatic ecosystems.

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Держатели документа:
Russian Acad Sci, Fed Res Ctr, Inst Biophys, Siberian Branch,Krasnoyarsk Sci Ctr,Lab Ecosyst B, 50-50 Akademgorodok, Krasnoyarsk 660036, Russia.
Russian Acad Sci, Fed Res Ctr, Inst Biophys, Siberian Branch,Krasnoyarsk Sci Ctr,Lab Biolumine, 50-50 Akademgorodok, Krasnoyarsk 660036, Russia.
Russian Acad Sci, Fed Res Ctr, Inst Biophys, Siberian Branch,Krasnoyarsk Sci Ctr,Analyt Lab, 50-50 Akademgorodok, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, Sch Fundamental Biol & Biotechnol, Dept Biophys, 79 Svobodniy Ave, Krasnoyarsk 660041, Russia.

Доп.точки доступа:
Lopatina, Tatiana S.; Aleksandrova, Yuliyana, V; Anishchenko, Olesya, V; Gribovskaya, Iliada, V; Oskina, Nataliya A.; Zotina, Tatiana A.; Zadereev, Egor S.; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR); Government of Krasnoyarsk Krai; Krasnoyarsk Krai Fund for Supporting Scientific and Scientific-Technical Activities [19-44-240014]

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18.

Constructing Slow-Release Metribuzin Formulations by Co-extrusion of the Pesticide with Poly-?-Caprolactone / A. N. Boyandin, E. A. Kazantseva // Macromol. Sympos. - 2021. - Vol. 395, Is. 1. - Ст. 2000283, DOI 10.1002/masy.202000283 . - ISSN 1022-1360
Кл.слова (ненормированные):
extrusion -- herbicides -- long-term -- pesticides -- polycaprolactone -- Biodegradable polymers -- Biodegradation -- Degradation -- Extrusion -- Melting -- Soils -- Weed control -- Biodegradable polyesters -- Caprolactone -- Degradation rate -- Long-term release -- Low cost methods -- Pesticide formulations -- Soil applications -- Soil degradation -- Herbicides
Аннотация: A simple and low-cost method of obtaining slow-release pesticide formulations is proposed by co-extrusion of a herbicide metribuzin with a low-melting biodegradable polyester poly-?-caprolactone, at a temperature above the melting points of both components. Formulations containing 10%, 20%, and 40% herbicide are prepared. Metribuzin release in water during 7 days of exposition reached 81% from the formulations with the 10% loading and 96% from the specimens with the 40% herbicide loading. Biodegradation and pesticide release from the polymer constructs are studied in the model soil for 14 weeks. Degradation rates of the specimens increased with an increase in pesticide content: between 9% for the 10%-loaded specimen and 20% for the 40%-loaded specimen over 14 weeks. The release of metribuzin from the specimens with the 10–20% and 40% loadings reached 37–38% and 55%, respectively; thus, taking into account soil degradation of the herbicide, the herbicide content in soil reached 23–25% and 33%, respectively, of the initially loaded into the polymer matrix. The used approach is promising to obtain long-term release formulations for soil application. © 2021 Wiley-VCH GmbH

Scopus
Держатели документа:
Institute of Biophysics of the Siberian Branch of the Russian Academy of Sciences, Federal Research Center “Krasnoyarsk Science Center of the Siberian Branch of the Russian Academy of Sciences”, 50/50 Akademgorodok, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, 79 Svobodny pr., Krasnoyarsk, 660041, Russian Federation

Доп.точки доступа:
Boyandin, A. N.; Kazantseva, E. A.

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19.

Constructing Slow-Release Metribuzin Formulations by Co-extrusion of the Pesticide with Poly-epsilon-Caprolactone / A. N. Boyandin, E. A. Kazantseva // Macromol. Symp. - 2021. - Vol. 395: 4th International Conference on Progress on Polymers and Composites (NOV 26-28, 2020, ELECTR NETWORK), Is. 1. - Ст. 2000283, DOI 10.1002/masy.202000283. - Cited References:6. - This study was financially supported 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". . - ISSN 1022-1360. - ISSN 1521-3900

РУБ Polymer Science

Кл.слова (ненормированные):
extrusion -- herbicides -- long‐ -- term -- pesticides -- polycaprolactone
Аннотация: A simple and low-cost method of obtaining slow-release pesticide formulations is proposed by co-extrusion of a herbicide metribuzin with a low-melting biodegradable polyester poly-epsilon-caprolactone, at a temperature above the melting points of both components. Formulations containing 10%, 20%, and 40% herbicide are prepared. Metribuzin release in water during 7 days of exposition reached 81% from the formulations with the 10% loading and 96% from the specimens with the 40% herbicide loading. Biodegradation and pesticide release from the polymer constructs are studied in the model soil for 14 weeks. Degradation rates of the specimens increased with an increase in pesticide content: between 9% for the 10%-loaded specimen and 20% for the 40%-loaded specimen over 14 weeks. The release of metribuzin from the specimens with the 10-20% and 40% loadings reached 37-38% and 55%, respectively; thus, taking into account soil degradation of the herbicide, the herbicide content in soil reached 23-25% and 33%, respectively, of the initially loaded into the polymer matrix. The used approach is promising to obtain long-term release formulations for soil application.

WOS
Держатели документа:
Russian Acad Sci, Krasnoyarsk Sci Ctr, Inst Biophys, Siberian Branch,Fed Res Ctr, 50-50 Akademgorodok, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, 79 Svobodny Pr, Krasnoyarsk 660041, Russia.

Доп.точки доступа:
Boyandin, Anatoly Nikolayevich; Kazantseva, Eugenia Andreevna; Government of the Russian Federation [220, 074-02-2018-328]

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20.

Constructing slow-release formulations of herbicide metribuzin using its co-extrusion with biodegradable polyester poly-epsilon-caprolactone / A. N. Boyandin, E. A. Kazantseva // J. Environ. Sci. Health Part B-Pestic. Contam. Agric. Wastes. - 2021, DOI 10.1080/03601234.2021.1911206. - Cited References:43. - This study was financially supported 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". . - Article in press. - ISSN 0360-1234. - ISSN 1532-4109

РУБ Environmental Sciences + Public, Environmental & Occupational Health

Кл.слова (ненормированные):
Polycaprolactone -- herbicide -- pesticide -- long-term -- extrusion
Аннотация: Different technologies to prepare long term pesticide forms include polymer coating, preparing composites and encapsulating pesticides in nanoparticles. A simple and low-cost method was proposed to obtain slow-release formulations by co-extrusion of a pesticide with a biodegradable polymer at a temperature above the melting points of both components. A herbicide metribuzin and low-melting polyester poly-epsilon-caprolactone were chosen for this work. Formulations containing 10%, 20%, and 40% herbicide were prepared. During 7 days of their exposition in water, it was released from 81% to 96% of initially loaded metribuzin; the highest release was detected for 40%-loaded forms. Biodegradation of the constructs and pesticide release were further studied in the model soil. Degradation rates of the specimens increased with an increase in pesticide content, from 9% to 20% over 14 weeks for the 10%/20%-loaded and the 40%-loaded specimens, respectively. The release of metribuzin reached, respectively, 37-38% and 55%. The herbicide content in soil was lower due to its partial degradation in soil; it reached 23-25% and 33%, respectively, from initially loaded into the polymer matrix. Release kinetics of metribuzin in water as in soil best fitted the First-order model. The used approach is promising for obtaining long-term release formulations for soil applications.

WOS
Держатели документа:
Russian Acad Sci, Krasnoyarsk Sci Ctr SB RAS, Fed Res Ctr, Inst Biophys,Siberian Branch, 50-50 Akademgorodok, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, Krasnoyarsk, Russia.

Доп.точки доступа:
Boyandin, Anatoly N.; Kazantseva, Eugenia A.; Boyandin, Anatoly; Project "Agropreparations of the new generation: a strategy of construction and realization" [074-02-2018-328]; Government of the Russian Federation [220]

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