TY  - JOUR
AU  - Pantić, Nevena
AU  - Spasojević, Milica
AU  - Stojanović, Željko
AU  - Veljović, Đorđe
AU  - Krstić, Jugoslav
AU  - Balaž, Ana Marija
AU  - Prodanović, Radivoje
AU  - Prodanović, Olivera
PY  - 2022
UR  - https://link.springer.com/article/10.1007/s10924-021-02364-3
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/5205
AB  - Novel macroporous copolymers of glycidyl methacrylate and ethylene glycol dimethacrylate with mean pore size diameters ranging from 150 to 310 nm were synthesized by dispersion polymerization and modified with ethylenediamine. The glutaraldehyde and periodate method were employed to immobilize horseradish peroxidase (HRP) onto these carriers. The activity of the immobilized enzyme was greatly affected by the pore size of the carrier. The highest specific activities of 9.65 and 8.94 U/g of dry weight were obtained for HRP immobilized by the periodate-route onto poly(GMA‐co‐EGDMA) carriers with pore size diameters of 234 and 297 nm, respectively. Stability studies showed an improved operational stability of immobilized peroxidase at 65 °C and in an organic solvent. HRP immobilized on a copolymer with a pore size of 234 nm, showing the highest specific activity and good stability, had higher activities at almost all pH values than the native enzyme and the increased Km value for pyrogallol oxidation. Immobilized HRP retained 80% of its original activity after five consecutive cycles of the pyrogallol oxidation and 98% of its initial activity in a storage stability study. Enzyme immobilized onto the macroporous copolymer with the pore size diameter of 234 nm showed a substantial degree of phenol removal achieved by immobilized peroxidase.
PB  - Springer
T2  - Journal of Polymers and the Environment
T1  - Immobilization of Horseradish Peroxidase on Macroporous Glycidyl-Based Copolymers with Different Surface Characteristics for the Removal of Phenol
VL  - 30
SP  - 3005
EP  - 3020
DO  - 10.1007/s10924-021-02364-3
ER  - 

@article{
author = "Pantić, Nevena and Spasojević, Milica and Stojanović, Željko and Veljović, Đorđe and Krstić, Jugoslav and Balaž, Ana Marija and Prodanović, Radivoje and Prodanović, Olivera",
year = "2022",
abstract = "Novel macroporous copolymers of glycidyl methacrylate and ethylene glycol dimethacrylate with mean pore size diameters ranging from 150 to 310 nm were synthesized by dispersion polymerization and modified with ethylenediamine. The glutaraldehyde and periodate method were employed to immobilize horseradish peroxidase (HRP) onto these carriers. The activity of the immobilized enzyme was greatly affected by the pore size of the carrier. The highest specific activities of 9.65 and 8.94 U/g of dry weight were obtained for HRP immobilized by the periodate-route onto poly(GMA‐co‐EGDMA) carriers with pore size diameters of 234 and 297 nm, respectively. Stability studies showed an improved operational stability of immobilized peroxidase at 65 °C and in an organic solvent. HRP immobilized on a copolymer with a pore size of 234 nm, showing the highest specific activity and good stability, had higher activities at almost all pH values than the native enzyme and the increased Km value for pyrogallol oxidation. Immobilized HRP retained 80% of its original activity after five consecutive cycles of the pyrogallol oxidation and 98% of its initial activity in a storage stability study. Enzyme immobilized onto the macroporous copolymer with the pore size diameter of 234 nm showed a substantial degree of phenol removal achieved by immobilized peroxidase.",
publisher = "Springer",
journal = "Journal of Polymers and the Environment",
title = "Immobilization of Horseradish Peroxidase on Macroporous Glycidyl-Based Copolymers with Different Surface Characteristics for the Removal of Phenol",
volume = "30",
pages = "3005-3020",
doi = "10.1007/s10924-021-02364-3"
}

Pantić, N., Spasojević, M., Stojanović, Ž., Veljović, Đ., Krstić, J., Balaž, A. M., Prodanović, R.,& Prodanović, O.. (2022). Immobilization of Horseradish Peroxidase on Macroporous Glycidyl-Based Copolymers with Different Surface Characteristics for the Removal of Phenol. in Journal of Polymers and the Environment
Springer., 30, 3005-3020.
https://doi.org/10.1007/s10924-021-02364-3

Pantić N, Spasojević M, Stojanović Ž, Veljović Đ, Krstić J, Balaž AM, Prodanović R, Prodanović O. Immobilization of Horseradish Peroxidase on Macroporous Glycidyl-Based Copolymers with Different Surface Characteristics for the Removal of Phenol. in Journal of Polymers and the Environment. 2022;30:3005-3020.
doi:10.1007/s10924-021-02364-3 .

Pantić, Nevena, Spasojević, Milica, Stojanović, Željko, Veljović, Đorđe, Krstić, Jugoslav, Balaž, Ana Marija, Prodanović, Radivoje, Prodanović, Olivera, "Immobilization of Horseradish Peroxidase on Macroporous Glycidyl-Based Copolymers with Different Surface Characteristics for the Removal of Phenol" in Journal of Polymers and the Environment, 30 (2022):3005-3020,
https://doi.org/10.1007/s10924-021-02364-3 . .

TY  - JOUR
AU  - Kovačević, Gordana
AU  - Elgahwash, Reyadh Gomah Amar
AU  - Blažić, Marija
AU  - Pantić, Nevena
AU  - Prodanović, Olivera
AU  - Balaž, Ana Marija
AU  - Prodanović, Radivoje
PY  - 2022
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/5979
AB  - Saccharomyces cerevisiae, known as bakers’ yeast, is one of the most utilized yeasts in industry. Several enzymes that are naturally produced by yeast, such as invertase and catalase, combined with heterologously expressed glucose oxidase (GOx), represent the enzyme machinery for fructose and gluconic acid production. Therefore, we have used yeast cell walls with expressed glucose oxidase as a platform for crosslinking with invertase and catalase to create biocatalyst cells for the high yield sucrose conversion. Using 5% (w/v) suspension of cross-linked yeast cell walls in 0.15 M sucrose solution, 1.86 g L−1 h−1 of gluconic acid has been obtained using wt-GOx, while mutant A2-GOx produced 2.91 g L−1 h−1 of gluconic acid. Increasing the concentration of modified yeast cells walls to 10% (w/v) we were able to obtain almost 100% conversion of glucose to gluconic acid using A2-GOx in the first cycle. Reusing the modified cells walls in three consecutive cycles, conversion dropped to approximately 70% using A2-GOx and 40% using wt-GOx.
PB  - Elsevier
T2  - Molecular Catalysis
T1  - Production of fructose and gluconic acid from sucrose with cross-linked yeast cell walls expressing glucose oxidase on the surface
VL  - 522
IS  - 112215
DO  - 10.1016/j.mcat.2022.112215
ER  - 

@article{
author = "Kovačević, Gordana and Elgahwash, Reyadh Gomah Amar and Blažić, Marija and Pantić, Nevena and Prodanović, Olivera and Balaž, Ana Marija and Prodanović, Radivoje",
year = "2022",
abstract = "Saccharomyces cerevisiae, known as bakers’ yeast, is one of the most utilized yeasts in industry. Several enzymes that are naturally produced by yeast, such as invertase and catalase, combined with heterologously expressed glucose oxidase (GOx), represent the enzyme machinery for fructose and gluconic acid production. Therefore, we have used yeast cell walls with expressed glucose oxidase as a platform for crosslinking with invertase and catalase to create biocatalyst cells for the high yield sucrose conversion. Using 5% (w/v) suspension of cross-linked yeast cell walls in 0.15 M sucrose solution, 1.86 g L−1 h−1 of gluconic acid has been obtained using wt-GOx, while mutant A2-GOx produced 2.91 g L−1 h−1 of gluconic acid. Increasing the concentration of modified yeast cells walls to 10% (w/v) we were able to obtain almost 100% conversion of glucose to gluconic acid using A2-GOx in the first cycle. Reusing the modified cells walls in three consecutive cycles, conversion dropped to approximately 70% using A2-GOx and 40% using wt-GOx.",
publisher = "Elsevier",
journal = "Molecular Catalysis",
title = "Production of fructose and gluconic acid from sucrose with cross-linked yeast cell walls expressing glucose oxidase on the surface",
volume = "522",
number = "112215",
doi = "10.1016/j.mcat.2022.112215"
}

Kovačević, G., Elgahwash, R. G. A., Blažić, M., Pantić, N., Prodanović, O., Balaž, A. M.,& Prodanović, R.. (2022). Production of fructose and gluconic acid from sucrose with cross-linked yeast cell walls expressing glucose oxidase on the surface. in Molecular Catalysis
Elsevier., 522(112215).
https://doi.org/10.1016/j.mcat.2022.112215

Kovačević G, Elgahwash RGA, Blažić M, Pantić N, Prodanović O, Balaž AM, Prodanović R. Production of fructose and gluconic acid from sucrose with cross-linked yeast cell walls expressing glucose oxidase on the surface. in Molecular Catalysis. 2022;522(112215).
doi:10.1016/j.mcat.2022.112215 .

Kovačević, Gordana, Elgahwash, Reyadh Gomah Amar, Blažić, Marija, Pantić, Nevena, Prodanović, Olivera, Balaž, Ana Marija, Prodanović, Radivoje, "Production of fructose and gluconic acid from sucrose with cross-linked yeast cell walls expressing glucose oxidase on the surface" in Molecular Catalysis, 522, no. 112215 (2022),
https://doi.org/10.1016/j.mcat.2022.112215 . .

TY  - JOUR
AU  - Pantić, Nevena
AU  - Prodanović, Radivoje
AU  - Ilić Đurđić, Karla
AU  - Polović, Natalija
AU  - Spasojević, Milica
AU  - Prodanović, Olivera
PY  - 2021
UR  - http://cherry.chem.bg.ac.rs/handle/123456789/4768
AB  - Removal of phenolic compounds from water is of major interest over the years, since they are one of the most common pollutants in aqueous systems. Horseradish peroxidase (HRP) is the most investigated biocatalyst for this purpose. Inactivation of the enzyme is a major issue which can be successfully overcome by the enzyme immobilization on different polymers. In this study, tyramine-alginate micro-beads were used as carriers for the immobilization of horseradish peroxidase. The effect of the oxidation degree of tyramine-alginates on a specific activity of the enzyme was tested. An increase in the concentration of oxidized alginate from 2.5 to 20% resulted in a gradual increase in the specific activity from 0.05 to 0.67 U/mL. HRP immobilized within these micro-beads was tested for the phenol removal in a batch reactor. Reaction conditions were optimized to achieve a high removal efficiency and substantial reusability of the system. In this study, for the first time, an internal generation of hydrogen peroxide from glucose and glucose oxidase was employed in the phenol removal process with HRP immobilized on tyramine-alginate. Within 6 h of repeated use 96% of phenol was removed when the system for internal delivery of H2O2, composed of 0.187 U/mL of glucose oxidase and 4 mmol/L of glucose was employed. A common straightforward addition of hydrogen peroxide provided the removal efficiency of only 42%, under the same reaction conditions. The highest efficiency of the phenol removal (96%) was obtained with HRP immobilized within 20 mol% oxidized tyramine-alginate micro-beads. Fifteen mol% oxidized tyramine-alginate showed lower removal efficiency in the first cycle of use (73%) but more promising reusability, since the immobilized enzyme retained 61% of its initial activity even after four consecutive cycles of use.
PB  - Elsevier
T2  - Environmental Technology & Innovation
T2  - Environmental Technology & InnovationEnvironmental Technology & Innovation
T1  - Optimization of phenol removal with horseradish peroxidase encapsulated within tyramine-alginate micro-beads
VL  - 21
SP  - 101211
DO  - 10.1016/j.eti.2020.101211
ER  - 

@article{
author = "Pantić, Nevena and Prodanović, Radivoje and Ilić Đurđić, Karla and Polović, Natalija and Spasojević, Milica and Prodanović, Olivera",
year = "2021",
abstract = "Removal of phenolic compounds from water is of major interest over the years, since they are one of the most common pollutants in aqueous systems. Horseradish peroxidase (HRP) is the most investigated biocatalyst for this purpose. Inactivation of the enzyme is a major issue which can be successfully overcome by the enzyme immobilization on different polymers. In this study, tyramine-alginate micro-beads were used as carriers for the immobilization of horseradish peroxidase. The effect of the oxidation degree of tyramine-alginates on a specific activity of the enzyme was tested. An increase in the concentration of oxidized alginate from 2.5 to 20% resulted in a gradual increase in the specific activity from 0.05 to 0.67 U/mL. HRP immobilized within these micro-beads was tested for the phenol removal in a batch reactor. Reaction conditions were optimized to achieve a high removal efficiency and substantial reusability of the system. In this study, for the first time, an internal generation of hydrogen peroxide from glucose and glucose oxidase was employed in the phenol removal process with HRP immobilized on tyramine-alginate. Within 6 h of repeated use 96% of phenol was removed when the system for internal delivery of H2O2, composed of 0.187 U/mL of glucose oxidase and 4 mmol/L of glucose was employed. A common straightforward addition of hydrogen peroxide provided the removal efficiency of only 42%, under the same reaction conditions. The highest efficiency of the phenol removal (96%) was obtained with HRP immobilized within 20 mol% oxidized tyramine-alginate micro-beads. Fifteen mol% oxidized tyramine-alginate showed lower removal efficiency in the first cycle of use (73%) but more promising reusability, since the immobilized enzyme retained 61% of its initial activity even after four consecutive cycles of use.",
publisher = "Elsevier",
journal = "Environmental Technology & Innovation, Environmental Technology & InnovationEnvironmental Technology & Innovation",
title = "Optimization of phenol removal with horseradish peroxidase encapsulated within tyramine-alginate micro-beads",
volume = "21",
pages = "101211",
doi = "10.1016/j.eti.2020.101211"
}

Pantić, N., Prodanović, R., Ilić Đurđić, K., Polović, N., Spasojević, M.,& Prodanović, O.. (2021). Optimization of phenol removal with horseradish peroxidase encapsulated within tyramine-alginate micro-beads. in Environmental Technology & Innovation
Elsevier., 21, 101211.
https://doi.org/10.1016/j.eti.2020.101211

Pantić N, Prodanović R, Ilić Đurđić K, Polović N, Spasojević M, Prodanović O. Optimization of phenol removal with horseradish peroxidase encapsulated within tyramine-alginate micro-beads. in Environmental Technology & Innovation. 2021;21:101211.
doi:10.1016/j.eti.2020.101211 .

Pantić, Nevena, Prodanović, Radivoje, Ilić Đurđić, Karla, Polović, Natalija, Spasojević, Milica, Prodanović, Olivera, "Optimization of phenol removal with horseradish peroxidase encapsulated within tyramine-alginate micro-beads" in Environmental Technology & Innovation, 21 (2021):101211,
https://doi.org/10.1016/j.eti.2020.101211 . .