TY  - JOUR
AU  - Dajić-Stevanović, Zora
AU  - Sieniawska, Elwira
AU  - Glowniak, Kazimierz
AU  - Obradović, Nataša
AU  - Pajić-Lijaković, Ivana
PY  - 2020
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5275
AB  - Essential oils (EOs) and their main constituents, the terpenes, are widely studied, mostly relating to their antioxidant ability and bioactivity, such as antimicrobial, anticancer, anti-inflammatory, and range of other actions in the living systems. However, there is limited information on their bioavailability, especially upon clinical studies. Having in mind both strong biological effects and health benefits of EOs and their specific physicochemical properties (volatility, lipophilic character, low water solubility or insolubility, viscosity, expressed odor, concentration-dependent toxicity, etc.), there is a need for their encapsulation for target delivery. Encapsulation of EOs and their constituents is the prerequisite for enhancing their oxidative stability, thermostability, photostability, shelf life, and biological activity. We considered various carrier types such a (1) monophase and polyphase polysaccharide hydrogel carriers, (2) polysaccharide-protein carriers, and (3) lipid carriers in the context of physicochemical and engineering factors. Physicochemical factors are encapsulation efficiency, chemical stability under gastric conditions, mechanical stability, and thermal stability of carrier matrices. Choice of carrier material also determines the encapsulation technique. Consequently, the engineering factors are related to the advantage and disadvantage of various encapsulation techniques frequently used in the literature. In addition, it was intended to address the interactions between (1) main carrier components, such as polysaccharides, proteins, and lipids themselves (in order to form chemically and mechanically stable structure); (2) main carrier components with pepsin under gastric conditions (in order to form resistant material under gastric conditions); and (3) main carrier components with EOs (in order to enhance encapsulation efficiency), as a necessary precondition for whole process optimization. Finally, different sources for obtaining natural carrier macromolecules are surveyed, especially the agro-waste materials and agricultural and food by-products. This review article highlights the bioavailability aspects of encapsulated EOs and physicochemical and engineering factors concerning natural macromolecule carriers for their target delivery and application.
PB  - Frontiers Media Sa, Lausanne
T2  - Frontiers in Bioengineering and Biotechnology
T1  - Natural Macromolecules as Carriers for Essential Oils: From Extraction to Biomedical Application
VL  - 8
DO  - 10.3389/fbioe.2020.00563
ER  - 

@article{
author = "Dajić-Stevanović, Zora and Sieniawska, Elwira and Glowniak, Kazimierz and Obradović, Nataša and Pajić-Lijaković, Ivana",
year = "2020",
abstract = "Essential oils (EOs) and their main constituents, the terpenes, are widely studied, mostly relating to their antioxidant ability and bioactivity, such as antimicrobial, anticancer, anti-inflammatory, and range of other actions in the living systems. However, there is limited information on their bioavailability, especially upon clinical studies. Having in mind both strong biological effects and health benefits of EOs and their specific physicochemical properties (volatility, lipophilic character, low water solubility or insolubility, viscosity, expressed odor, concentration-dependent toxicity, etc.), there is a need for their encapsulation for target delivery. Encapsulation of EOs and their constituents is the prerequisite for enhancing their oxidative stability, thermostability, photostability, shelf life, and biological activity. We considered various carrier types such a (1) monophase and polyphase polysaccharide hydrogel carriers, (2) polysaccharide-protein carriers, and (3) lipid carriers in the context of physicochemical and engineering factors. Physicochemical factors are encapsulation efficiency, chemical stability under gastric conditions, mechanical stability, and thermal stability of carrier matrices. Choice of carrier material also determines the encapsulation technique. Consequently, the engineering factors are related to the advantage and disadvantage of various encapsulation techniques frequently used in the literature. In addition, it was intended to address the interactions between (1) main carrier components, such as polysaccharides, proteins, and lipids themselves (in order to form chemically and mechanically stable structure); (2) main carrier components with pepsin under gastric conditions (in order to form resistant material under gastric conditions); and (3) main carrier components with EOs (in order to enhance encapsulation efficiency), as a necessary precondition for whole process optimization. Finally, different sources for obtaining natural carrier macromolecules are surveyed, especially the agro-waste materials and agricultural and food by-products. This review article highlights the bioavailability aspects of encapsulated EOs and physicochemical and engineering factors concerning natural macromolecule carriers for their target delivery and application.",
publisher = "Frontiers Media Sa, Lausanne",
journal = "Frontiers in Bioengineering and Biotechnology",
title = "Natural Macromolecules as Carriers for Essential Oils: From Extraction to Biomedical Application",
volume = "8",
doi = "10.3389/fbioe.2020.00563"
}

Dajić-Stevanović, Z., Sieniawska, E., Glowniak, K., Obradović, N.,& Pajić-Lijaković, I.. (2020). Natural Macromolecules as Carriers for Essential Oils: From Extraction to Biomedical Application. in Frontiers in Bioengineering and Biotechnology
Frontiers Media Sa, Lausanne., 8.
https://doi.org/10.3389/fbioe.2020.00563

Dajić-Stevanović Z, Sieniawska E, Glowniak K, Obradović N, Pajić-Lijaković I. Natural Macromolecules as Carriers for Essential Oils: From Extraction to Biomedical Application. in Frontiers in Bioengineering and Biotechnology. 2020;8.
doi:10.3389/fbioe.2020.00563 .

Dajić-Stevanović, Zora, Sieniawska, Elwira, Glowniak, Kazimierz, Obradović, Nataša, Pajić-Lijaković, Ivana, "Natural Macromolecules as Carriers for Essential Oils: From Extraction to Biomedical Application" in Frontiers in Bioengineering and Biotechnology, 8 (2020),
https://doi.org/10.3389/fbioe.2020.00563 . .

TY  - CHAP
AU  - Pajić-Lijaković, Ivana
AU  - Milivojević, M.
AU  - Lević, Steva
AU  - Trifković, Kata
AU  - Balanc, Bojana
AU  - Nedović, Viktor
AU  - Dajić-Stevanović, Zora
AU  - Radošević, Radenko
AU  - Bugarski, Branko
PY  - 2019
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5142
AB  - Some of the main rheological properties that Ca-alginate hydrogel matrix should satisfy for biomedical and biotechnological applications are the matrix viscoelasticity and the ability of stress relaxation. Although alginate satisfies both of them, experimental data note that cell growth is significantly reduced by microenvironmental effects. Microenvironmental restriction effects are connected to matrix resistance stress accumulation. Matrix stress is generated within the boundary layers around the cell aggregates under compression caused by cell rearrangement and growth. Simultaneously induced relaxation phenomena of both subsystems: (1) immobilized cells and (2) hydrogel matrix occur at three time scales through successive relaxation cycles. Complex dynamics of matrix compression intensifies mechanical and electrostatic cell-matrix interactions. Minimizing of the resistance stress is the strategy for improving the matrix performances. Cell action could be simulated in the experiments without cells during repeated stress relaxation cycles. We consider the physical and chemical modifications of Ca-alginate hydrogel.
PB  - Elsevier
T2  - Materials for Biomedical Engineering: Bioactive Materials, Properties, and Applications
T1  - Matrix resistance stress reduction-prerequisite for achieving higher concentration of immobilized cells
EP  - 306
SP  - 281
DO  - 10.1016/B978-0-12-818431-8.00009-X
ER  - 

@inbook{
author = "Pajić-Lijaković, Ivana and Milivojević, M. and Lević, Steva and Trifković, Kata and Balanc, Bojana and Nedović, Viktor and Dajić-Stevanović, Zora and Radošević, Radenko and Bugarski, Branko",
year = "2019",
abstract = "Some of the main rheological properties that Ca-alginate hydrogel matrix should satisfy for biomedical and biotechnological applications are the matrix viscoelasticity and the ability of stress relaxation. Although alginate satisfies both of them, experimental data note that cell growth is significantly reduced by microenvironmental effects. Microenvironmental restriction effects are connected to matrix resistance stress accumulation. Matrix stress is generated within the boundary layers around the cell aggregates under compression caused by cell rearrangement and growth. Simultaneously induced relaxation phenomena of both subsystems: (1) immobilized cells and (2) hydrogel matrix occur at three time scales through successive relaxation cycles. Complex dynamics of matrix compression intensifies mechanical and electrostatic cell-matrix interactions. Minimizing of the resistance stress is the strategy for improving the matrix performances. Cell action could be simulated in the experiments without cells during repeated stress relaxation cycles. We consider the physical and chemical modifications of Ca-alginate hydrogel.",
publisher = "Elsevier",
journal = "Materials for Biomedical Engineering: Bioactive Materials, Properties, and Applications",
booktitle = "Matrix resistance stress reduction-prerequisite for achieving higher concentration of immobilized cells",
pages = "306-281",
doi = "10.1016/B978-0-12-818431-8.00009-X"
}

Pajić-Lijaković, I., Milivojević, M., Lević, S., Trifković, K., Balanc, B., Nedović, V., Dajić-Stevanović, Z., Radošević, R.,& Bugarski, B.. (2019). Matrix resistance stress reduction-prerequisite for achieving higher concentration of immobilized cells. in Materials for Biomedical Engineering: Bioactive Materials, Properties, and Applications
Elsevier., 281-306.
https://doi.org/10.1016/B978-0-12-818431-8.00009-X

Pajić-Lijaković I, Milivojević M, Lević S, Trifković K, Balanc B, Nedović V, Dajić-Stevanović Z, Radošević R, Bugarski B. Matrix resistance stress reduction-prerequisite for achieving higher concentration of immobilized cells. in Materials for Biomedical Engineering: Bioactive Materials, Properties, and Applications. 2019;:281-306.
doi:10.1016/B978-0-12-818431-8.00009-X .

Pajić-Lijaković, Ivana, Milivojević, M., Lević, Steva, Trifković, Kata, Balanc, Bojana, Nedović, Viktor, Dajić-Stevanović, Zora, Radošević, Radenko, Bugarski, Branko, "Matrix resistance stress reduction-prerequisite for achieving higher concentration of immobilized cells" in Materials for Biomedical Engineering: Bioactive Materials, Properties, and Applications (2019):281-306,
https://doi.org/10.1016/B978-0-12-818431-8.00009-X . .

TY  - JOUR
AU  - Dajić-Stevanović, Zora
AU  - Bosnjak-Neumuller, Jasna
AU  - Pajić-Lijaković, Ivana
AU  - Raj, Jog
AU  - Vasiljević, Marko
PY  - 2018
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4631
AB  - The inconsistency of phytogenic feed additives' (PFA) effects on the livestock industry poses a risk for their use as a replacement for antibiotic growth promoters. The livestock market is being encouraged to use natural growth promotors, but information is limited about the PFA mode of action. The aim of this paper is to present the complexity of compounds present in essential oils (EOs) and factors that influence biological effects of PFA. In this paper, we highlight various controls and optimization parameters that influence the processes for the standardization of these products. The chemical composition of EOs depends on plant genetics, growth conditions, development stage at harvest, and processes of extracting active compounds. Their biological effects are further influenced by the interaction of phytochemicals and their bioavailability in the gastrointestinal tract of animals. PFA effects on animal health and production are also complex due to various EO antibiotic, antioxidant, anti-quorum sensing, anti-inflammatory, and digestive fluids stimulating activities. Research must focus on reliable methods to identify and control the quality and effects of EOs. In this study, we focused on available microencapsulation techniques of EOs to increase the bioavailability of active compounds, as well as their application in the animal feed additive industry.
PB  - MDPI, BASEL
T2  - Molecules
T1  - Essential Oils as Feed AdditivesFuture Perspectives
IS  - 7
VL  - 23
DO  - 10.3390/molecules23071717
ER  - 

@article{
author = "Dajić-Stevanović, Zora and Bosnjak-Neumuller, Jasna and Pajić-Lijaković, Ivana and Raj, Jog and Vasiljević, Marko",
year = "2018",
abstract = "The inconsistency of phytogenic feed additives' (PFA) effects on the livestock industry poses a risk for their use as a replacement for antibiotic growth promoters. The livestock market is being encouraged to use natural growth promotors, but information is limited about the PFA mode of action. The aim of this paper is to present the complexity of compounds present in essential oils (EOs) and factors that influence biological effects of PFA. In this paper, we highlight various controls and optimization parameters that influence the processes for the standardization of these products. The chemical composition of EOs depends on plant genetics, growth conditions, development stage at harvest, and processes of extracting active compounds. Their biological effects are further influenced by the interaction of phytochemicals and their bioavailability in the gastrointestinal tract of animals. PFA effects on animal health and production are also complex due to various EO antibiotic, antioxidant, anti-quorum sensing, anti-inflammatory, and digestive fluids stimulating activities. Research must focus on reliable methods to identify and control the quality and effects of EOs. In this study, we focused on available microencapsulation techniques of EOs to increase the bioavailability of active compounds, as well as their application in the animal feed additive industry.",
publisher = "MDPI, BASEL",
journal = "Molecules",
title = "Essential Oils as Feed AdditivesFuture Perspectives",
number = "7",
volume = "23",
doi = "10.3390/molecules23071717"
}

Dajić-Stevanović, Z., Bosnjak-Neumuller, J., Pajić-Lijaković, I., Raj, J.,& Vasiljević, M.. (2018). Essential Oils as Feed AdditivesFuture Perspectives. in Molecules
MDPI, BASEL., 23(7).
https://doi.org/10.3390/molecules23071717

Dajić-Stevanović Z, Bosnjak-Neumuller J, Pajić-Lijaković I, Raj J, Vasiljević M. Essential Oils as Feed AdditivesFuture Perspectives. in Molecules. 2018;23(7).
doi:10.3390/molecules23071717 .

Dajić-Stevanović, Zora, Bosnjak-Neumuller, Jasna, Pajić-Lijaković, Ivana, Raj, Jog, Vasiljević, Marko, "Essential Oils as Feed AdditivesFuture Perspectives" in Molecules, 23, no. 7 (2018),
https://doi.org/10.3390/molecules23071717 . .

TY  - JOUR
AU  - Volić, Mina
AU  - Pajić-Lijaković, Ivana
AU  - Djordjević, Verica B.
AU  - Knežević-Jugović, Zorica
AU  - Pećinar, Ilinka
AU  - Dajić-Stevanović, Zora
AU  - Veljović, Djordje
AU  - Hadnadjev, Miroslav
AU  - Bugarski, Branko
PY  - 2018
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4665
AB  - Preparation of alginate-soy protein isolate (AL/SPI) complex beads containing essential oil of thyme was carried out by emulsification of thyme oil in aqueous sodium alginate solution blended with SPI solution, followed by atomization via electrostatic extrusion and gelification with calcium ions. The process parameters were optimized by variation of the alginate (1-2.5 wt.%) and SPI (0-1.5 wt.%) concentrations. Dry alginate-SPI particles exhibited wrinkle surface while shape distortion of hydrogel beads occurred with >= 1.5 wt.% alginate concentration, whereas SPI induced reduction of the particle size. Encapsulation efficiency of 72-80 % based on total polyphenols was achieved. In SGF the samples exhibited oil release of 42-55 % (due to matrix shrinkage and proteins degradation by pepsin activity), while the rest was delivered in SIF within 2.5 h simultaneously with swelling and degradation of the matrix.
PB  - Elsevier Sci Ltd, Oxford
T2  - Carbohydrate Polymers
T1  - Alginate/soy protein system for essential oil encapsulation with intestinal delivery
EP  - 24
SP  - 15
VL  - 200
DO  - 10.1016/j.carbpol.2018.07.033
ER  - 

@article{
author = "Volić, Mina and Pajić-Lijaković, Ivana and Djordjević, Verica B. and Knežević-Jugović, Zorica and Pećinar, Ilinka and Dajić-Stevanović, Zora and Veljović, Djordje and Hadnadjev, Miroslav and Bugarski, Branko",
year = "2018",
abstract = "Preparation of alginate-soy protein isolate (AL/SPI) complex beads containing essential oil of thyme was carried out by emulsification of thyme oil in aqueous sodium alginate solution blended with SPI solution, followed by atomization via electrostatic extrusion and gelification with calcium ions. The process parameters were optimized by variation of the alginate (1-2.5 wt.%) and SPI (0-1.5 wt.%) concentrations. Dry alginate-SPI particles exhibited wrinkle surface while shape distortion of hydrogel beads occurred with >= 1.5 wt.% alginate concentration, whereas SPI induced reduction of the particle size. Encapsulation efficiency of 72-80 % based on total polyphenols was achieved. In SGF the samples exhibited oil release of 42-55 % (due to matrix shrinkage and proteins degradation by pepsin activity), while the rest was delivered in SIF within 2.5 h simultaneously with swelling and degradation of the matrix.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Carbohydrate Polymers",
title = "Alginate/soy protein system for essential oil encapsulation with intestinal delivery",
pages = "24-15",
volume = "200",
doi = "10.1016/j.carbpol.2018.07.033"
}

Volić, M., Pajić-Lijaković, I., Djordjević, V. B., Knežević-Jugović, Z., Pećinar, I., Dajić-Stevanović, Z., Veljović, D., Hadnadjev, M.,& Bugarski, B.. (2018). Alginate/soy protein system for essential oil encapsulation with intestinal delivery. in Carbohydrate Polymers
Elsevier Sci Ltd, Oxford., 200, 15-24.
https://doi.org/10.1016/j.carbpol.2018.07.033

Volić M, Pajić-Lijaković I, Djordjević VB, Knežević-Jugović Z, Pećinar I, Dajić-Stevanović Z, Veljović D, Hadnadjev M, Bugarski B. Alginate/soy protein system for essential oil encapsulation with intestinal delivery. in Carbohydrate Polymers. 2018;200:15-24.
doi:10.1016/j.carbpol.2018.07.033 .

Volić, Mina, Pajić-Lijaković, Ivana, Djordjević, Verica B., Knežević-Jugović, Zorica, Pećinar, Ilinka, Dajić-Stevanović, Zora, Veljović, Djordje, Hadnadjev, Miroslav, Bugarski, Branko, "Alginate/soy protein system for essential oil encapsulation with intestinal delivery" in Carbohydrate Polymers, 200 (2018):15-24,
https://doi.org/10.1016/j.carbpol.2018.07.033 . .

TY  - JOUR
AU  - Pajić-Lijaković, Ivana
AU  - Milivojević, Milan
AU  - Lević, Steva
AU  - Trifković, Kata
AU  - Dajić-Stevanović, Zora
AU  - Radošević, Radenko
AU  - Nedović, Viktor
AU  - Bugarski, Branko
PY  - 2017
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4366
AB  - Microenvironmentally restricted yeast cell growth within Ca-alginate beads with and without entrapped gas bubbles was considered based on experimental data. Cell growth dynamics was described by (1) the dimensionless cell number density as a function of the cell growth time and (2) the cell distribution per bead cross sections. One of the key control parameters for bioprocess optimization is the matrix resistance stress generated during immobilized cell expansion. The dynamics of the increase in matrix stress was described theoretically based on a multi-scale mathematical model. In order to estimate and reduce the accumulation of matrix stress we considered repeated stress relaxation cycles in separate rheological experiments without immobilized cells. The results revealed that the increase in resistance stress within the Ca-alginate matrix was significant (similar to 7 kPa) after 10 repeated cycles, even under a low compression strain of 2% per cycle. The stress could be reduced by using the Ca-alginate matrix with entrapped gas bubbles. The final cell concentration within the beads with entrapped bubbles was 3.3 times higher in comparison with the beads without bubbles. The bubbles could locally amortize the compression effects within the surrounding cell clusters.
PB  - Elsevier Sci Ltd, Oxford
T2  - Process Biochemistry
T1  - Matrix resistance stress: A key parameter for immobilized cell growth regulation
EP  - 43
SP  - 30
VL  - 52
DO  - 10.1016/j.procbio.2016.10.017
ER  - 

@article{
author = "Pajić-Lijaković, Ivana and Milivojević, Milan and Lević, Steva and Trifković, Kata and Dajić-Stevanović, Zora and Radošević, Radenko and Nedović, Viktor and Bugarski, Branko",
year = "2017",
abstract = "Microenvironmentally restricted yeast cell growth within Ca-alginate beads with and without entrapped gas bubbles was considered based on experimental data. Cell growth dynamics was described by (1) the dimensionless cell number density as a function of the cell growth time and (2) the cell distribution per bead cross sections. One of the key control parameters for bioprocess optimization is the matrix resistance stress generated during immobilized cell expansion. The dynamics of the increase in matrix stress was described theoretically based on a multi-scale mathematical model. In order to estimate and reduce the accumulation of matrix stress we considered repeated stress relaxation cycles in separate rheological experiments without immobilized cells. The results revealed that the increase in resistance stress within the Ca-alginate matrix was significant (similar to 7 kPa) after 10 repeated cycles, even under a low compression strain of 2% per cycle. The stress could be reduced by using the Ca-alginate matrix with entrapped gas bubbles. The final cell concentration within the beads with entrapped bubbles was 3.3 times higher in comparison with the beads without bubbles. The bubbles could locally amortize the compression effects within the surrounding cell clusters.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Process Biochemistry",
title = "Matrix resistance stress: A key parameter for immobilized cell growth regulation",
pages = "43-30",
volume = "52",
doi = "10.1016/j.procbio.2016.10.017"
}

Pajić-Lijaković, I., Milivojević, M., Lević, S., Trifković, K., Dajić-Stevanović, Z., Radošević, R., Nedović, V.,& Bugarski, B.. (2017). Matrix resistance stress: A key parameter for immobilized cell growth regulation. in Process Biochemistry
Elsevier Sci Ltd, Oxford., 52, 30-43.
https://doi.org/10.1016/j.procbio.2016.10.017

Pajić-Lijaković I, Milivojević M, Lević S, Trifković K, Dajić-Stevanović Z, Radošević R, Nedović V, Bugarski B. Matrix resistance stress: A key parameter for immobilized cell growth regulation. in Process Biochemistry. 2017;52:30-43.
doi:10.1016/j.procbio.2016.10.017 .

Pajić-Lijaković, Ivana, Milivojević, Milan, Lević, Steva, Trifković, Kata, Dajić-Stevanović, Zora, Radošević, Radenko, Nedović, Viktor, Bugarski, Branko, "Matrix resistance stress: A key parameter for immobilized cell growth regulation" in Process Biochemistry, 52 (2017):30-43,
https://doi.org/10.1016/j.procbio.2016.10.017 . .

TY  - JOUR
AU  - Belović, Miona
AU  - Pajić-Lijaković, Ivana
AU  - Torbica, Aleksandra
AU  - Mastilović, Jasna
AU  - Pećinar, Ilinka
PY  - 2016
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4031
AB  - The influence of concentration and temperature on the rheological properties of tomato pomace dispersions obtained by rehydration of lyophilized and grinded tomato pomace was investigated in this paper. Examined systems comprised of different lyophilized tomato pomace concentrations (18.2, 16.7, 14.3, 12.5, 11.1, 10.0, and 9.1%) heat treated at two different temperatures (60 degrees C and 100 degrees C) during 30 min. According to microstructure analysis of the studied system, it could be simplified as the composite consisting of insoluble particles surrounded by the pectin network. The system behaves as viscoelastic solid (G' > G '' at all angular velocities), and therefore the static modulus of elasticity, the effective modulus and the damping coefficient were determined by application of modified fractional Kelvin-Voigt model. The influence of particle concentration on the rheological properties of tomato pomace system is dominant in comparison to the content and composition of pectin solubilised in the serum. Concentrated tomato pomace dispersions are much stiffer (G' values an order of magnitude higher) than the composite systems. Heat treatment at higher temperature (100 degrees C) decreases the stiffness of the system by breaking of non-covalent bonds between dispersed tomato particles and surrounding pectin network. Storage modulus as a function of the tomato pomace lyophilizate concentration was considered within three regimes (regime 1 - concentration  lt 11.1%; regime 2 - concentration 11.1%-16.7%; regime 3 - concentration > 16.7%) that could be used as the base for formulation of tomato pomace-based products with different desirable consistencies, such as sauce, ketchup and marmalade.
PB  - Elsevier Sci Ltd, Oxford
T2  - Food Hydrocolloids
T1  - The influence of concentration and temperature on the viscoelastic properties of tomato pomace dispersions
EP  - 624
SP  - 617
VL  - 61
DO  - 10.1016/j.foodhyd.2016.06.021
ER  - 

@article{
author = "Belović, Miona and Pajić-Lijaković, Ivana and Torbica, Aleksandra and Mastilović, Jasna and Pećinar, Ilinka",
year = "2016",
abstract = "The influence of concentration and temperature on the rheological properties of tomato pomace dispersions obtained by rehydration of lyophilized and grinded tomato pomace was investigated in this paper. Examined systems comprised of different lyophilized tomato pomace concentrations (18.2, 16.7, 14.3, 12.5, 11.1, 10.0, and 9.1%) heat treated at two different temperatures (60 degrees C and 100 degrees C) during 30 min. According to microstructure analysis of the studied system, it could be simplified as the composite consisting of insoluble particles surrounded by the pectin network. The system behaves as viscoelastic solid (G' > G '' at all angular velocities), and therefore the static modulus of elasticity, the effective modulus and the damping coefficient were determined by application of modified fractional Kelvin-Voigt model. The influence of particle concentration on the rheological properties of tomato pomace system is dominant in comparison to the content and composition of pectin solubilised in the serum. Concentrated tomato pomace dispersions are much stiffer (G' values an order of magnitude higher) than the composite systems. Heat treatment at higher temperature (100 degrees C) decreases the stiffness of the system by breaking of non-covalent bonds between dispersed tomato particles and surrounding pectin network. Storage modulus as a function of the tomato pomace lyophilizate concentration was considered within three regimes (regime 1 - concentration  lt 11.1%; regime 2 - concentration 11.1%-16.7%; regime 3 - concentration > 16.7%) that could be used as the base for formulation of tomato pomace-based products with different desirable consistencies, such as sauce, ketchup and marmalade.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Food Hydrocolloids",
title = "The influence of concentration and temperature on the viscoelastic properties of tomato pomace dispersions",
pages = "624-617",
volume = "61",
doi = "10.1016/j.foodhyd.2016.06.021"
}

Belović, M., Pajić-Lijaković, I., Torbica, A., Mastilović, J.,& Pećinar, I.. (2016). The influence of concentration and temperature on the viscoelastic properties of tomato pomace dispersions. in Food Hydrocolloids
Elsevier Sci Ltd, Oxford., 61, 617-624.
https://doi.org/10.1016/j.foodhyd.2016.06.021

Belović M, Pajić-Lijaković I, Torbica A, Mastilović J, Pećinar I. The influence of concentration and temperature on the viscoelastic properties of tomato pomace dispersions. in Food Hydrocolloids. 2016;61:617-624.
doi:10.1016/j.foodhyd.2016.06.021 .

Belović, Miona, Pajić-Lijaković, Ivana, Torbica, Aleksandra, Mastilović, Jasna, Pećinar, Ilinka, "The influence of concentration and temperature on the viscoelastic properties of tomato pomace dispersions" in Food Hydrocolloids, 61 (2016):617-624,
https://doi.org/10.1016/j.foodhyd.2016.06.021 . .

TY  - JOUR
AU  - Pajić-Lijaković, Ivana
AU  - Lević, Steva
AU  - Hadnadjev, Miroslav
AU  - Dajić-Stevanović, Zora
AU  - Radošević, Radenko
AU  - Nedović, Viktor
AU  - Bugarski, Branko
PY  - 2015
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3701
AB  - Structural changes of Ca-alginate bead due to yeast cell loading and the impact on their mechanical properties were studied based on experimental data of cell number density per beads, cell rearrangement within the bead surface and core regions, bead average volume and density, bead storage and loss moduli. Structural changes could be explained by (1) mechanical and electrostatic cell-matrix interactions and (2) chemical interactions of the matrix with the components of the nutrition medium which include: wash out of Ca2+ ions by presence of non-gelling ions and by chelating compounds such as phosphate. According to obtained results, it was estimated that: (1) cell-matrix electrostatic interactions within the hydrogel matrix at t=0 induced the bead weakening, (2) wash out of Ca2+ ions by presence of non-gelling ions and by chelating compounds such as phosphate led to the bead weakening (regime 1, t is an element of (left perpendicular0, 2 daysright perpendicular), (3) the bead stiffness remained constant (regime 2, t is an element of (left perpendicular2, 4 daysright perpendicular)) and (4) the bead reinforcement was caused by cell clusters rapid increase and their inter connections within the bead surface region (regime 3, t is an element of (left perpendicular4, 5 daysright perpendicular)). Regulation of the matrix resistance stress and the rate of its change could lead to decrease of the micro-environmental restriction effects and the whole process optimization.
PB  - Elsevier Science Bv, Amsterdam
T2  - Biochemical Engineering Journal
T1  - Structural changes of Ca-alginate beads caused by immobilized yeast cell growth
EP  - 38
SP  - 32
VL  - 103
DO  - 10.1016/j.bej.2015.06.016
ER  - 

@article{
author = "Pajić-Lijaković, Ivana and Lević, Steva and Hadnadjev, Miroslav and Dajić-Stevanović, Zora and Radošević, Radenko and Nedović, Viktor and Bugarski, Branko",
year = "2015",
abstract = "Structural changes of Ca-alginate bead due to yeast cell loading and the impact on their mechanical properties were studied based on experimental data of cell number density per beads, cell rearrangement within the bead surface and core regions, bead average volume and density, bead storage and loss moduli. Structural changes could be explained by (1) mechanical and electrostatic cell-matrix interactions and (2) chemical interactions of the matrix with the components of the nutrition medium which include: wash out of Ca2+ ions by presence of non-gelling ions and by chelating compounds such as phosphate. According to obtained results, it was estimated that: (1) cell-matrix electrostatic interactions within the hydrogel matrix at t=0 induced the bead weakening, (2) wash out of Ca2+ ions by presence of non-gelling ions and by chelating compounds such as phosphate led to the bead weakening (regime 1, t is an element of (left perpendicular0, 2 daysright perpendicular), (3) the bead stiffness remained constant (regime 2, t is an element of (left perpendicular2, 4 daysright perpendicular)) and (4) the bead reinforcement was caused by cell clusters rapid increase and their inter connections within the bead surface region (regime 3, t is an element of (left perpendicular4, 5 daysright perpendicular)). Regulation of the matrix resistance stress and the rate of its change could lead to decrease of the micro-environmental restriction effects and the whole process optimization.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Biochemical Engineering Journal",
title = "Structural changes of Ca-alginate beads caused by immobilized yeast cell growth",
pages = "38-32",
volume = "103",
doi = "10.1016/j.bej.2015.06.016"
}

Pajić-Lijaković, I., Lević, S., Hadnadjev, M., Dajić-Stevanović, Z., Radošević, R., Nedović, V.,& Bugarski, B.. (2015). Structural changes of Ca-alginate beads caused by immobilized yeast cell growth. in Biochemical Engineering Journal
Elsevier Science Bv, Amsterdam., 103, 32-38.
https://doi.org/10.1016/j.bej.2015.06.016

Pajić-Lijaković I, Lević S, Hadnadjev M, Dajić-Stevanović Z, Radošević R, Nedović V, Bugarski B. Structural changes of Ca-alginate beads caused by immobilized yeast cell growth. in Biochemical Engineering Journal. 2015;103:32-38.
doi:10.1016/j.bej.2015.06.016 .

Pajić-Lijaković, Ivana, Lević, Steva, Hadnadjev, Miroslav, Dajić-Stevanović, Zora, Radošević, Radenko, Nedović, Viktor, Bugarski, Branko, "Structural changes of Ca-alginate beads caused by immobilized yeast cell growth" in Biochemical Engineering Journal, 103 (2015):32-38,
https://doi.org/10.1016/j.bej.2015.06.016 . .

TY  - JOUR
AU  - Lević, Steva
AU  - Pajić-Lijaković, Ivana
AU  - Djordjević, Verica
AU  - Rac, Vladislav
AU  - Rakić, Vesna
AU  - Šolević-Knudsen, Tatjana
AU  - Pavlović, Vladimir
AU  - Bugarski, Branko
AU  - Nedović, Viktor
PY  - 2015
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3777
AB  - In this study, calcium alginate beads immobilizing D-limonene (solid systems) have been manufactured starting from emulsions of this flavor in sodium alginate (liquid systems). The effects of alginate concentration (0.02 and 0.03 g/mL) and flavor content (5 and 10 % w/w) on viscosity, conductivity and stability of emulsions were investigated. The flavor droplets in emulsions are bigger as polymer solution is more concentrated and contains more of the flavor. When emulsions have been subjected to electrostatic extrusion and upon Na+-Ca2+ ion exchange, smaller (similar to 960 to similar to 1450 mm) and less spherical beads were obtained (sphericity factor 0.003-0.21) compared to beads produced by simple dripping technique (without electrostatic field). When wet beads were air dried, they shrunk less if they had higher content of the flavor. Novel mathematical model describing swelling kinetics of dried beads is developed. In this work, D-limonene was efficiently immobilized within Ca-alginate beads (immobilization efficiency similar to 50 to similar to 77%) and its thermal stability was confirmed by TG/MS analysis.
PB  - Elsevier Sci Ltd, Oxford
T2  - Food Hydrocolloids
T1  - Characterization of sodium alginate/D-limonene emulsions and respective calcium alginate/D-limonene beads produced by electrostatic extrusion
EP  - 123
SP  - 111
VL  - 45
DO  - 10.1016/j.foodhyd.2014.10.001
ER  - 

@article{
author = "Lević, Steva and Pajić-Lijaković, Ivana and Djordjević, Verica and Rac, Vladislav and Rakić, Vesna and Šolević-Knudsen, Tatjana and Pavlović, Vladimir and Bugarski, Branko and Nedović, Viktor",
year = "2015",
abstract = "In this study, calcium alginate beads immobilizing D-limonene (solid systems) have been manufactured starting from emulsions of this flavor in sodium alginate (liquid systems). The effects of alginate concentration (0.02 and 0.03 g/mL) and flavor content (5 and 10 % w/w) on viscosity, conductivity and stability of emulsions were investigated. The flavor droplets in emulsions are bigger as polymer solution is more concentrated and contains more of the flavor. When emulsions have been subjected to electrostatic extrusion and upon Na+-Ca2+ ion exchange, smaller (similar to 960 to similar to 1450 mm) and less spherical beads were obtained (sphericity factor 0.003-0.21) compared to beads produced by simple dripping technique (without electrostatic field). When wet beads were air dried, they shrunk less if they had higher content of the flavor. Novel mathematical model describing swelling kinetics of dried beads is developed. In this work, D-limonene was efficiently immobilized within Ca-alginate beads (immobilization efficiency similar to 50 to similar to 77%) and its thermal stability was confirmed by TG/MS analysis.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Food Hydrocolloids",
title = "Characterization of sodium alginate/D-limonene emulsions and respective calcium alginate/D-limonene beads produced by electrostatic extrusion",
pages = "123-111",
volume = "45",
doi = "10.1016/j.foodhyd.2014.10.001"
}

Lević, S., Pajić-Lijaković, I., Djordjević, V., Rac, V., Rakić, V., Šolević-Knudsen, T., Pavlović, V., Bugarski, B.,& Nedović, V.. (2015). Characterization of sodium alginate/D-limonene emulsions and respective calcium alginate/D-limonene beads produced by electrostatic extrusion. in Food Hydrocolloids
Elsevier Sci Ltd, Oxford., 45, 111-123.
https://doi.org/10.1016/j.foodhyd.2014.10.001

Lević S, Pajić-Lijaković I, Djordjević V, Rac V, Rakić V, Šolević-Knudsen T, Pavlović V, Bugarski B, Nedović V. Characterization of sodium alginate/D-limonene emulsions and respective calcium alginate/D-limonene beads produced by electrostatic extrusion. in Food Hydrocolloids. 2015;45:111-123.
doi:10.1016/j.foodhyd.2014.10.001 .

Lević, Steva, Pajić-Lijaković, Ivana, Djordjević, Verica, Rac, Vladislav, Rakić, Vesna, Šolević-Knudsen, Tatjana, Pavlović, Vladimir, Bugarski, Branko, Nedović, Viktor, "Characterization of sodium alginate/D-limonene emulsions and respective calcium alginate/D-limonene beads produced by electrostatic extrusion" in Food Hydrocolloids, 45 (2015):111-123,
https://doi.org/10.1016/j.foodhyd.2014.10.001 . .

TY  - CONF
AU  - Plavsić, M.B.
AU  - Pajić-Lijaković, Ivana
AU  - Bugarski, Branko
AU  - Budinski-Simendić, J.
AU  - Nedović, Viktor
AU  - Putanov, P.
PY  - 2010
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/2155
AB  - Living cell organization in clusters is considered in terms of cell-cells and cells-microenvironment interactions as important factor in fundamental understanding of cell behavior in formation and grow of living tissues, wound heeling and development some serious illness, but also in present tissue engineering, immobilization of cells in polymer matrices and culture grow. Significant importance of parameters as compacivity and compressibility for quantification of cell behavior is found as well as possibility for modeling cell organization in terms of classical models of polymer structure as blends. The theory of Karasz and coworkers on miscibility widows in polymer blends is used for interpretation of some polymer-cell relations.
C3  - ACS Symposium Series
T1  - Pseudo-blend model of hydrogel immobilized living cellst
EP  - 229
SP  - 215
VL  - 1061
DO  - 10.1021/bk-2010-1061.ch014
ER  - 

@conference{
author = "Plavsić, M.B. and Pajić-Lijaković, Ivana and Bugarski, Branko and Budinski-Simendić, J. and Nedović, Viktor and Putanov, P.",
year = "2010",
abstract = "Living cell organization in clusters is considered in terms of cell-cells and cells-microenvironment interactions as important factor in fundamental understanding of cell behavior in formation and grow of living tissues, wound heeling and development some serious illness, but also in present tissue engineering, immobilization of cells in polymer matrices and culture grow. Significant importance of parameters as compacivity and compressibility for quantification of cell behavior is found as well as possibility for modeling cell organization in terms of classical models of polymer structure as blends. The theory of Karasz and coworkers on miscibility widows in polymer blends is used for interpretation of some polymer-cell relations.",
journal = "ACS Symposium Series",
title = "Pseudo-blend model of hydrogel immobilized living cellst",
pages = "229-215",
volume = "1061",
doi = "10.1021/bk-2010-1061.ch014"
}

Plavsić, M.B., Pajić-Lijaković, I., Bugarski, B., Budinski-Simendić, J., Nedović, V.,& Putanov, P.. (2010). Pseudo-blend model of hydrogel immobilized living cellst. in ACS Symposium Series, 1061, 215-229.
https://doi.org/10.1021/bk-2010-1061.ch014

Plavsić M, Pajić-Lijaković I, Bugarski B, Budinski-Simendić J, Nedović V, Putanov P. Pseudo-blend model of hydrogel immobilized living cellst. in ACS Symposium Series. 2010;1061:215-229.
doi:10.1021/bk-2010-1061.ch014 .

Plavsić, M.B., Pajić-Lijaković, Ivana, Bugarski, Branko, Budinski-Simendić, J., Nedović, Viktor, Putanov, P., "Pseudo-blend model of hydrogel immobilized living cellst" in ACS Symposium Series, 1061 (2010):215-229,
https://doi.org/10.1021/bk-2010-1061.ch014 . .

TY  - CONF
AU  - Pajić-Lijaković, Ivana
AU  - Plavsić, M.
AU  - Nedović, Viktor
AU  - Bugarski, Branko
PY  - 2008
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/1638
AB  - Aim. A phase-field mathematical model was formulated to describe yeast cell growth within the Ca-alginate microbead during air-lift bioreactor cultivation. Model development was based on experimentally obtained data for the intra-bead yeast cell volume fraction profile within the microbead after reaching the equilibrium state for cells (150 h), as well as, total yeast cell volume fraction per microbead and microbead volume as functions time. Microbead with growing yeast cells is treated as a two-phase system. one phase represents the cell agglomerates, while the other is the alginate hydrogel matrices. The interactions between phases are simulated using the Langevin class, non-conservative phasefield model based on the reduction of the modeling resolution. The model considered the growth of small domains of one phase (cell agglomerates) as nucleation. Methods. Total yeast cell volume fraction in the beads was estimated by using Thoma counting chamber after dissolution of beads. Local cell volume fraction per microbead layers is calculated from experimentally determined surface fraction of cells for various microbead cross sections by image analysis. Microbead volume is estimated by measuring the microbead diameter. Diameters of microbeads were measured using the optical microscope equipped with a micrometric device. Results. The proposed model offered the only one model parameter, which represents the specific measure of microenvironmental restrictive action to the cell growth dynamics. The optimal value of this model parameter is obtained by comparison analysis between experimental data and model predictions. Conclusion. Besides giving useful insights into the dynamics of restrictive cell growth within the Ca-alginate microbead, the model can be used as a tool to design/optimize the performance of microbead and studying the microenvironmental restrictive mechanism action of the cell growth.
C3  - Minerva Biotecnologica
T1  - Modeling of microenvironmetal restricted yeast cell growth within Ca-alginate microbead
EP  - 102
IS  - 2
SP  - 99
VL  - 20
UR  - https://hdl.handle.net/21.15107/rcub_agrospace_1638
ER  - 

@conference{
author = "Pajić-Lijaković, Ivana and Plavsić, M. and Nedović, Viktor and Bugarski, Branko",
year = "2008",
abstract = "Aim. A phase-field mathematical model was formulated to describe yeast cell growth within the Ca-alginate microbead during air-lift bioreactor cultivation. Model development was based on experimentally obtained data for the intra-bead yeast cell volume fraction profile within the microbead after reaching the equilibrium state for cells (150 h), as well as, total yeast cell volume fraction per microbead and microbead volume as functions time. Microbead with growing yeast cells is treated as a two-phase system. one phase represents the cell agglomerates, while the other is the alginate hydrogel matrices. The interactions between phases are simulated using the Langevin class, non-conservative phasefield model based on the reduction of the modeling resolution. The model considered the growth of small domains of one phase (cell agglomerates) as nucleation. Methods. Total yeast cell volume fraction in the beads was estimated by using Thoma counting chamber after dissolution of beads. Local cell volume fraction per microbead layers is calculated from experimentally determined surface fraction of cells for various microbead cross sections by image analysis. Microbead volume is estimated by measuring the microbead diameter. Diameters of microbeads were measured using the optical microscope equipped with a micrometric device. Results. The proposed model offered the only one model parameter, which represents the specific measure of microenvironmental restrictive action to the cell growth dynamics. The optimal value of this model parameter is obtained by comparison analysis between experimental data and model predictions. Conclusion. Besides giving useful insights into the dynamics of restrictive cell growth within the Ca-alginate microbead, the model can be used as a tool to design/optimize the performance of microbead and studying the microenvironmental restrictive mechanism action of the cell growth.",
journal = "Minerva Biotecnologica",
title = "Modeling of microenvironmetal restricted yeast cell growth within Ca-alginate microbead",
pages = "102-99",
number = "2",
volume = "20",
url = "https://hdl.handle.net/21.15107/rcub_agrospace_1638"
}

Pajić-Lijaković, I., Plavsić, M., Nedović, V.,& Bugarski, B.. (2008). Modeling of microenvironmetal restricted yeast cell growth within Ca-alginate microbead. in Minerva Biotecnologica, 20(2), 99-102.
https://hdl.handle.net/21.15107/rcub_agrospace_1638

Pajić-Lijaković I, Plavsić M, Nedović V, Bugarski B. Modeling of microenvironmetal restricted yeast cell growth within Ca-alginate microbead. in Minerva Biotecnologica. 2008;20(2):99-102.
https://hdl.handle.net/21.15107/rcub_agrospace_1638 .

Pajić-Lijaković, Ivana, Plavsić, M., Nedović, Viktor, Bugarski, Branko, "Modeling of microenvironmetal restricted yeast cell growth within Ca-alginate microbead" in Minerva Biotecnologica, 20, no. 2 (2008):99-102,
https://hdl.handle.net/21.15107/rcub_agrospace_1638 .

TY  - JOUR
AU  - Pajić-Lijaković, Ivana
AU  - Plavsić, Milenko
AU  - Bugarski, Branko
AU  - Nedović, Viktor
PY  - 2007
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/1494
AB  - A mathematical model was formulated to describe yeast cell growth within the Ca-alginate microbead during air-lift bioreactor cultivation. Model development was based on experimentally obtained data for the intra-bead cell concentration profile, after reached the equilibrium state, as well as, total yeast cell concentration per microbed and microbead volume as function of time. Relatively uniform cell concentration in the carrier matrix indicated that no internal nutrient diffusion limitations, but microenvironmental restriction, affected dominantly the dynamics of cell growth. Also interesting phenomenon of very different rates of cell number growth during cultivation is observed. After some critical time, the growth rate of cell colonies decreased drastically, but than suddenly increased again under all other experimental condition been the same. It is interpreted as disintegration of gel network and opening new free space for growth of cell clusters. These complex phenomena are modeled using the thermodynamical, free energy formalism. The particular form of free energy functional is proposed to describe various kinds of interactions, which affected the dynamics of cell growth and cause pseudo-phase transition of hydrogel. The good agreement of experimentally obtained data and model predictions are obtained. In that way the model provides both, the quantitative tools for further technological optimization of the process and deeper insight into dynamics of cell growth mechanism.
PB  - Elsevier, Amsterdam
T2  - Journal of Biotechnology
T1  - Ca-alginate hydrogel mechanical transformations - The influence on yeast cell growth dynamics
EP  - 452
IS  - 3
SP  - 446
VL  - 129
DO  - 10.1016/j.jbiotec.2007.01.017
ER  - 

@article{
author = "Pajić-Lijaković, Ivana and Plavsić, Milenko and Bugarski, Branko and Nedović, Viktor",
year = "2007",
abstract = "A mathematical model was formulated to describe yeast cell growth within the Ca-alginate microbead during air-lift bioreactor cultivation. Model development was based on experimentally obtained data for the intra-bead cell concentration profile, after reached the equilibrium state, as well as, total yeast cell concentration per microbed and microbead volume as function of time. Relatively uniform cell concentration in the carrier matrix indicated that no internal nutrient diffusion limitations, but microenvironmental restriction, affected dominantly the dynamics of cell growth. Also interesting phenomenon of very different rates of cell number growth during cultivation is observed. After some critical time, the growth rate of cell colonies decreased drastically, but than suddenly increased again under all other experimental condition been the same. It is interpreted as disintegration of gel network and opening new free space for growth of cell clusters. These complex phenomena are modeled using the thermodynamical, free energy formalism. The particular form of free energy functional is proposed to describe various kinds of interactions, which affected the dynamics of cell growth and cause pseudo-phase transition of hydrogel. The good agreement of experimentally obtained data and model predictions are obtained. In that way the model provides both, the quantitative tools for further technological optimization of the process and deeper insight into dynamics of cell growth mechanism.",
publisher = "Elsevier, Amsterdam",
journal = "Journal of Biotechnology",
title = "Ca-alginate hydrogel mechanical transformations - The influence on yeast cell growth dynamics",
pages = "452-446",
number = "3",
volume = "129",
doi = "10.1016/j.jbiotec.2007.01.017"
}

Pajić-Lijaković, I., Plavsić, M., Bugarski, B.,& Nedović, V.. (2007). Ca-alginate hydrogel mechanical transformations - The influence on yeast cell growth dynamics. in Journal of Biotechnology
Elsevier, Amsterdam., 129(3), 446-452.
https://doi.org/10.1016/j.jbiotec.2007.01.017

Pajić-Lijaković I, Plavsić M, Bugarski B, Nedović V. Ca-alginate hydrogel mechanical transformations - The influence on yeast cell growth dynamics. in Journal of Biotechnology. 2007;129(3):446-452.
doi:10.1016/j.jbiotec.2007.01.017 .

Pajić-Lijaković, Ivana, Plavsić, Milenko, Bugarski, Branko, Nedović, Viktor, "Ca-alginate hydrogel mechanical transformations - The influence on yeast cell growth dynamics" in Journal of Biotechnology, 129, no. 3 (2007):446-452,
https://doi.org/10.1016/j.jbiotec.2007.01.017 . .

TY  - JOUR
AU  - Pajić-Lijaković, Ivana
AU  - Plavsić, Milenko
AU  - Nedović, Viktor
AU  - Bugarski, Branko
PY  - 2007
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/1489
AB  - The rheological model is developed to elucidate the mechanism of Ca-alginate microbead deformation in the course of cell growth within. It is a complex process influenced by relaxation of the expanded polymer network inside a bead, and forces generated by cell growth inside the bead and interactions between solvent, network parts and cells as well. The resulting effects are measured experimentally by estimating isotropic volumetric deformations of beads with yeast cells as function of time and cell concentration per bead. The mathematical model of the process is developed based on a modified general Zener model with fractional derivatives. It is particularly suitable for incorporating effects of different nature also during different stages of such complex process development. The results of theoretical analyses using the model developed and comparison with experimental values obtained, indicate a high impact of partial decomposition, i.e. plastic response of polymer network inside a bead due to cell growth, on bead deformation. For comparison, corresponding deformation measurements and modelling were performed on the same network system exposed to swelling in the solvent, but without the cells. In this case elastic forces are dominant, indicating different mechanism of relaxation without the influence of cells, in agreement with previous conclusions.
PB  - Taylor & Francis Ltd, Abingdon
T2  - Journal of Microencapsulation
T1  - Investigation of Ca-alginate hydrogel rheological behaviour in conjunction with immobilized yeast cell growth dynamics
EP  - 429
IS  - 5
SP  - 420
VL  - 24
DO  - 10.1080/02652040701362843
ER  - 

@article{
author = "Pajić-Lijaković, Ivana and Plavsić, Milenko and Nedović, Viktor and Bugarski, Branko",
year = "2007",
abstract = "The rheological model is developed to elucidate the mechanism of Ca-alginate microbead deformation in the course of cell growth within. It is a complex process influenced by relaxation of the expanded polymer network inside a bead, and forces generated by cell growth inside the bead and interactions between solvent, network parts and cells as well. The resulting effects are measured experimentally by estimating isotropic volumetric deformations of beads with yeast cells as function of time and cell concentration per bead. The mathematical model of the process is developed based on a modified general Zener model with fractional derivatives. It is particularly suitable for incorporating effects of different nature also during different stages of such complex process development. The results of theoretical analyses using the model developed and comparison with experimental values obtained, indicate a high impact of partial decomposition, i.e. plastic response of polymer network inside a bead due to cell growth, on bead deformation. For comparison, corresponding deformation measurements and modelling were performed on the same network system exposed to swelling in the solvent, but without the cells. In this case elastic forces are dominant, indicating different mechanism of relaxation without the influence of cells, in agreement with previous conclusions.",
publisher = "Taylor & Francis Ltd, Abingdon",
journal = "Journal of Microencapsulation",
title = "Investigation of Ca-alginate hydrogel rheological behaviour in conjunction with immobilized yeast cell growth dynamics",
pages = "429-420",
number = "5",
volume = "24",
doi = "10.1080/02652040701362843"
}

Pajić-Lijaković, I., Plavsić, M., Nedović, V.,& Bugarski, B.. (2007). Investigation of Ca-alginate hydrogel rheological behaviour in conjunction with immobilized yeast cell growth dynamics. in Journal of Microencapsulation
Taylor & Francis Ltd, Abingdon., 24(5), 420-429.
https://doi.org/10.1080/02652040701362843

Pajić-Lijaković I, Plavsić M, Nedović V, Bugarski B. Investigation of Ca-alginate hydrogel rheological behaviour in conjunction with immobilized yeast cell growth dynamics. in Journal of Microencapsulation. 2007;24(5):420-429.
doi:10.1080/02652040701362843 .

Pajić-Lijaković, Ivana, Plavsić, Milenko, Nedović, Viktor, Bugarski, Branko, "Investigation of Ca-alginate hydrogel rheological behaviour in conjunction with immobilized yeast cell growth dynamics" in Journal of Microencapsulation, 24, no. 5 (2007):420-429,
https://doi.org/10.1080/02652040701362843 . .

TY  - CONF
AU  - Pajić-Lijaković, Ivana
AU  - Nedović, Viktor
AU  - Bugarski, Branko
PY  - 2006
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/1346
AB  - The nonlinear dynamics of brewing yeast cell growth in porous Ca-alginate matrices is considered experimentally and theoretically. The applications of alginate matrices include the reduction of internal mass transfer resistance, minimized cell leakage and growth restriction due to interactions between matrices and cell membranes comparatively to free cell culture conditions. The effects of micro-bead diameters in the range 0.3-2.0 mm on yeast cell growth were investigated. The stochastic mathematical model from the Langevin class is proposed for the interpretation of cell growth, affected by four micro-processes: micro-environmental quality changes due to nutrient diffusion into the micro-beads, cell leakage, repulsive interactions between boundary layers around the cells themselves, which contribute to the dynamics of cell growth as a negative, nonlinear feedback restriction and random kinetics effects. Such a model is used for the prediction of the optimal diameter of micro-beads, which ensures maximal final cell concentration. The results of cell growth in alginate matrices study have indicated an optimal diameter of 0.5-0.6 mm for micro-beads. Immobilized cells in these beads were not restricted significantly by mass transfer of nutrients and by cell leakage. The highest final cell concentration value indicated the largest feed-back restriction quantified by the constitutive parameter b.
PB  - Trans Tech Publications Ltd, Durnten-Zurich
C3  - Recent Developments in Advanced Materials and Processes
T1  - Nonlinear dynamics of brewing yeast cell growth in alginate micro-beads
EP  - 524
SP  - 519
VL  - 518
DO  - 10.4028/www.scientific.net/MSF.518.519
ER  - 

@conference{
author = "Pajić-Lijaković, Ivana and Nedović, Viktor and Bugarski, Branko",
year = "2006",
abstract = "The nonlinear dynamics of brewing yeast cell growth in porous Ca-alginate matrices is considered experimentally and theoretically. The applications of alginate matrices include the reduction of internal mass transfer resistance, minimized cell leakage and growth restriction due to interactions between matrices and cell membranes comparatively to free cell culture conditions. The effects of micro-bead diameters in the range 0.3-2.0 mm on yeast cell growth were investigated. The stochastic mathematical model from the Langevin class is proposed for the interpretation of cell growth, affected by four micro-processes: micro-environmental quality changes due to nutrient diffusion into the micro-beads, cell leakage, repulsive interactions between boundary layers around the cells themselves, which contribute to the dynamics of cell growth as a negative, nonlinear feedback restriction and random kinetics effects. Such a model is used for the prediction of the optimal diameter of micro-beads, which ensures maximal final cell concentration. The results of cell growth in alginate matrices study have indicated an optimal diameter of 0.5-0.6 mm for micro-beads. Immobilized cells in these beads were not restricted significantly by mass transfer of nutrients and by cell leakage. The highest final cell concentration value indicated the largest feed-back restriction quantified by the constitutive parameter b.",
publisher = "Trans Tech Publications Ltd, Durnten-Zurich",
journal = "Recent Developments in Advanced Materials and Processes",
title = "Nonlinear dynamics of brewing yeast cell growth in alginate micro-beads",
pages = "524-519",
volume = "518",
doi = "10.4028/www.scientific.net/MSF.518.519"
}

Pajić-Lijaković, I., Nedović, V.,& Bugarski, B.. (2006). Nonlinear dynamics of brewing yeast cell growth in alginate micro-beads. in Recent Developments in Advanced Materials and Processes
Trans Tech Publications Ltd, Durnten-Zurich., 518, 519-524.
https://doi.org/10.4028/www.scientific.net/MSF.518.519

Pajić-Lijaković I, Nedović V, Bugarski B. Nonlinear dynamics of brewing yeast cell growth in alginate micro-beads. in Recent Developments in Advanced Materials and Processes. 2006;518:519-524.
doi:10.4028/www.scientific.net/MSF.518.519 .

Pajić-Lijaković, Ivana, Nedović, Viktor, Bugarski, Branko, "Nonlinear dynamics of brewing yeast cell growth in alginate micro-beads" in Recent Developments in Advanced Materials and Processes, 518 (2006):519-524,
https://doi.org/10.4028/www.scientific.net/MSF.518.519 . .

TY  - JOUR
AU  - Pajić-Lijaković, Ivana
AU  - Bugarski, Branko
AU  - Nedović, Viktor
AU  - Plavsić, M.
PY  - 2005
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/1102
AB  - Aim. The aggregation of phospholipid vesicles (liposomes) in water is analyzed experimentally and theoretically and compared with the well-examined alumina dispersions. The steady-state aggregation followed rheologically for various volume fractions of particles and shear rates. Methods. A micro-rheological model of aggregating dispersions is proposed in which the apparent viscosity is estimated as the sum of hydrodynamic and structural parts, which are correlated with system structural ordering. Langevin equation is used to describe the dynamics of evolution of steady-states of liposome systems in phase space, for various shear rates. Results. These results established a link between the local dynamics of liposome dispersions and their flow behavior. Conclusion. Aggregates become more compact and embedded higher volume of fluid when shear rate increases. Hydrodynamic part of viscosity increases, while structural part of viscosity decreases with shear rate. Calculated value of bond energy between liposomes corresponds to hydrogen bond energy.
PB  - Edizioni Minerva Medica, Turin
T2  - Minerva Biotecnologica
T1  - Rheological quantification of liposomes aggregation
EP  - 249
IS  - 4
SP  - 245
VL  - 17
UR  - https://hdl.handle.net/21.15107/rcub_agrospace_1102
ER  - 

@article{
author = "Pajić-Lijaković, Ivana and Bugarski, Branko and Nedović, Viktor and Plavsić, M.",
year = "2005",
abstract = "Aim. The aggregation of phospholipid vesicles (liposomes) in water is analyzed experimentally and theoretically and compared with the well-examined alumina dispersions. The steady-state aggregation followed rheologically for various volume fractions of particles and shear rates. Methods. A micro-rheological model of aggregating dispersions is proposed in which the apparent viscosity is estimated as the sum of hydrodynamic and structural parts, which are correlated with system structural ordering. Langevin equation is used to describe the dynamics of evolution of steady-states of liposome systems in phase space, for various shear rates. Results. These results established a link between the local dynamics of liposome dispersions and their flow behavior. Conclusion. Aggregates become more compact and embedded higher volume of fluid when shear rate increases. Hydrodynamic part of viscosity increases, while structural part of viscosity decreases with shear rate. Calculated value of bond energy between liposomes corresponds to hydrogen bond energy.",
publisher = "Edizioni Minerva Medica, Turin",
journal = "Minerva Biotecnologica",
title = "Rheological quantification of liposomes aggregation",
pages = "249-245",
number = "4",
volume = "17",
url = "https://hdl.handle.net/21.15107/rcub_agrospace_1102"
}

Pajić-Lijaković, I., Bugarski, B., Nedović, V.,& Plavsić, M.. (2005). Rheological quantification of liposomes aggregation. in Minerva Biotecnologica
Edizioni Minerva Medica, Turin., 17(4), 245-249.
https://hdl.handle.net/21.15107/rcub_agrospace_1102

Pajić-Lijaković I, Bugarski B, Nedović V, Plavsić M. Rheological quantification of liposomes aggregation. in Minerva Biotecnologica. 2005;17(4):245-249.
https://hdl.handle.net/21.15107/rcub_agrospace_1102 .

Pajić-Lijaković, Ivana, Bugarski, Branko, Nedović, Viktor, Plavsić, M., "Rheological quantification of liposomes aggregation" in Minerva Biotecnologica, 17, no. 4 (2005):245-249,
https://hdl.handle.net/21.15107/rcub_agrospace_1102 .